Vancomicina contra metronidazol en infección por Clostridioides difficile leve-moderada de manejo ambulatorio / Vancomycin or metronidazole in the outpatient treatment of mild-moderate Clostridioides difficile infection

INTRODUCCIÓN: En la diarrea asociada a Clostridioides dfficile (DACD) leve-moderada se recomienda tratar con vancomicina por sobre metronidazol, a pesar de su difícil acceso y poca evidencia en el medio ambulatorio. OBJETIVO: Comparar la tasa de cura clínica y recurrencia entre vancomicina y metronidazol en adultos chilenos con primer episodio leve-moderado de DACD de manejo ambulatorio. MÉTODOS: Cohorte retrospectiva entre enero 2015 y diciembre 2020 en centros de una red de salud universitaria de pacientes de ≥ 18 años con DACD tratados ambulatoriamente. RESULTADOS: Se obtuvieron 161 pacientes, 59% mujeres, edad promedio de 53 años (entre 18 y 94 años). De ellos, 109 (67,7%) usaron metronidazol y 52 (32,3%) vancomicina. En el análisis multivariado ajustado por edad y comorbilidades se obtuvo un OR 3,00 (IC 95% 1,12-9,59) para cura clínica y 0,27 (IC 95% 0,06-0,88) para recurrencia a ocho semanas, ambos a favor de vancomicina, sin diferencias en recurrencia a 12 meses, necesidad de hospitalización o mortalidad. CONCLUSIÓN: La terapia con vancomicina comparada contra metronidazol en el tratamiento ambulatorio de la infección leve-moderada por C. dfficile se asocia a mayor cura clínica y menor tasa de recurrencia a corto plazo, sin diferencias en desenlaces a largo plazo.

BACKGROUND: Recommended treatment against mild cases of Clostridioides difficile associated diarrhea is vancomycin despite the difficulties of access compared to metronidazole. AIM: To compare the effectiveness of vancomycin and metronidazole in Chilean adults with first mild-moderate episode of Clostridiodes difficile infection (CDI). METHODS: Retrospective cohort of patients with CDI between January 2015 and December 2020 treated in centers of a university health network. The patients were adults treated for C. difficile infection on an outpatient basis. Recurrent and severe cases were excluded. Outcomes included clinical cure and recurrence rate. RESULTS: Data from 161 patients was recovered. Fifty-nine percent were women and average age was 53 (18-94). One hundred and nine patients were treated with metronidazole (67.7%) and 52 (32.3%) used vancomycin. Multivariate analysis adjusted by age and comorbidities showed an Odds Ratio of 3.00 (IC 95% 1.12-9.59) for clinical cure and 0.27 (IC 95% 0.06-0.88) for 8-week recurrence rate, both in favor of vancomycin, without differences in 12-month recurrence rate, hospitalization rate nor mortality. CONCLUSIONS: Vancomycin is associated with better short-term outcomes in the treatment of outpatient mild-moderate first episode C. difficile infection, without differences in long term recurrence or mortality when compared with metronidazole.

Megacolon tóxico: A propósito de un caso / Toxic Megacolon. Case Report

RESUMEN El megacolon tóxico es una enfermedad mortal, que se presenta, con mayor frecuencia, como una complicación de la inflamación intestinal, infecciones e isquemia intestinal. Se caracteriza por la presencia de diarrea sanguinolenta, distensión abdominal, signos de toxicidad sistémica y, en estudios de imagen, se observa dilatación colónica segmentaria. Para el diagnóstico, según los criterios de Jalan, se tiene en cuenta la dilatación colónica más de 6 cm, tres de los siguientes: fiebre, taquicardia, leucocitosis o anemia, y cualquiera de los siguientes criterios: hipotensión, hipovolemia, trastorno electrolítico y estado mental alterado. En este artículo, se presenta el caso de una paciente mujer que ingresa por cuadro de dolor abdominal y diarrea crónica con estudio de imagen, en la que se visualiza dilatación de todo el marco colónico. Se realizan los estudios correspondientes y se diagnostica megacolon tóxico por colitis ulcerativa, por lo que recibe tratamiento médico con evolución favorable. Es dado de alta y reingresa por shock séptico, se realizan estudios y se identifica infección por Clostridium difficile. Se inicia tratamiento antibiótico, pero presenta evolución desfavorable, lo que ocasionó el fallecimiento de la paciente. El presente caso representa la alta mortalidad de esta enfermedad.

ABSTRACT Toxic megacolon is a fatal disease, most commonly occurring as a complication of inflammatory bowel disease, infections, and intestinal ischemia. It is characterized by the presence of bloody diarrhea, abdominal distension, signs of systemic toxicity, and segmental colonic dilation is observed in imaging studies. For the diagnosis, according to the Jalan criteria, colonic dilation of more than 6 cm is taken into account, three of the following: fever, tachycardia, leukocytosis or anemia, and any of the following criteria: hypotension, hypovolemia, electrolyte disorder and altered mental status. This article presents the case of a female patient who was admitted with abdominal pain and chronic diarrhea with an imaging study showing dilation of the entire colonic framework. The corresponding studies were carried out which indicated that she had a toxic megacolon due to colitis. ulcerative, receives medical treatment with favorable evolution, is discharged and readmitted for septic shock, studies are performed and Clostridium difficile infection is identified, antibiotic treatment is started but the evolution is unfavorable, which caused the death of the patient. The present case represents the high mortality of this disease.

Clinical Efficacy of Clostridium Difficile Infection in Children / 医学研究杂志

Objective To analyze the clinical characteristics and treatment of clostridium difficile infection(CDI)in children.Methods The clinical data of 159 children with CDI admitted to the Department of Gastroenterology and Hepatology,Shanghai Children's Hospital,School of Medicine,Shanghai Jiao Tong University from September 2014 to October 2022 were retrospectively analyzed.All ini-tial CDI patients were divided into vancomycin treatment group and metronidazole treatment group according to different treatment meth-ods,Children with recurrent CDI(RCDI)were divided into two groups according to vancomycin or FMT treatment.Results A total of 159 children with initial CDI were included,including 93 males and 66 females,the age of these children was 4.3(1.7,8.0)years.109 children(68.55％)were treated with metronidazole,and 50 children(31.45％)were treated with vancomycin.Recurrence occurred in 51 children after antibiotic treatment,37 children(33.94％)of them treated with metronidazole,and 14 children(28.00％)of them treated with vancomycin,there was no significant difference(P＞0.05).Among RCDI children,21 cases were treated with vancomycin and 30 were treated with FMT.The cure rate of FMT was 90.00％,and the cure rate of vancomycin was 57.14％.The cure rate of FMT was significantly higher than that of vancomycin.There were no serious adverse events reported after two months of FMT treatment.Conclusion Metronidazole can be used as the drug of choice for initial CDI in children.The cure rate of FMT for RCDI is superior to vancomycin treatment.

Study on the Inhibitory of Pyruvate-Ferredoxin Oxidoreductase by Luteolin and Its Anti-Clostridium Difficile Effect / 中药新药与临床药理

Objective To investigate the inhibitory effects of pyruvate-ferredoxin oxidoreductase(PFOR)by luteolin and its anti-Clostridium difficile effect.Methods The PFOR encoding sequence of Clostridium difficile was cloned into the expression vector pET-2a and transformed into competent Escherichia coli.The crude enzyme was prepared after induction with IPTG(Isopropyl β-D-Thiogalactoside).The inhibitory rate of the test compounds on PFOR was determined after an 8-hour anaerobic reaction between PFOR and 40 μmol·L-1 of test compounds at 25℃.The minimum inhibitory concentration(MIC)of PFOR inhibitors against C.difficile strains(ATCC BAA 1382 and ATCC BAA 1870)was determined by monitoring the OD600 of the bacterial culture.Molecular docking was performed to investigate the possible interaction mechanisms between PFOR and inhibitors.Results Among the tested compounds,the luteolin showed the strongest inhibitory activity against PFOR,with a single-point inhibition rate of approximately 33%,which is comparable to that observed with the positive inhibitor nitazoxanide(40%).Molecular docking revealed that luteolin could form hydrogen bonds with Asp428,Val431,Gly429,Asp456,Lys458,Lys459,and other residues in the PFOR domain.The MIC of luteolin against C.difficile was approximately 32 μg·mL-1.Conclusion Luteolin exhibits good activity against C.difficile,and PFOR may be a target for its antibacterial action.

Advances in the application of fecal microbiota transplantation in infec-tious diseases / 中国感染控制杂志

Intestinal flora plays an important role in the process of resisting infectious diseases.Fecal microbiota transplantation(FMT)is an important method for reconstructing intestinal microbiota,mainly includes washed mi-crobiota transplantation,transendoscopic enteral tubing,and spore group transplantation.In 2022,the Standardiza-tion Administration of China released the technical standards for Quality control of fecal microbiota washing and grading of fecal microbiota specimens,aiming to reduce adverse events related to FMT and improve the acceptance of FMT by patients and medical personnel.After the success of FMT in the treatment of recurrent Clostridioides difficile infection,its application in the treatment of other infectious diseases has also become a global research hotspot.This paper reviews the development of FMT and its application in various infectious diseases.

Molecular epidemiology and antimicrobial resistance in Clostridioides difficile strains isolated from children and adolescents in a tertiary referral pediatric hospital in Fortaleza, Brazil

Abstract Background C. difficile has been increasingly reported as a cause of gastrointestinal disease in children, ranging from mild self-limiting diarrhea to severe conditions such as pseudomembranous colitis and toxic megacolon. Only two pediatric research groups reported the presence of C. difficile infection in Brazilian children, but no previous research has examined C. difficile infection among children in northeastern Brazil. This prospective cross-sectional study investigated the molecular epidemiology and antimicrobial resistance of C. difficile strains isolated from children and adolescents with diarrhea referred to a tertiary pediatric hospital in Brazil while exploring the associated risk factors. Results Toxin positivity or C. difficile isolation was found in 30.4 % (17/56) samples. C. difficile was isolated from 35 % (6/17) samples. Four toxigenic strains were identified (tpi+, tcdA+, tcdB+, cdtB-, without tcdC deletions) belonging to PCR ribotypes and PFGE-pulsotypes: 046 (new pulsotype 1174), 106 (NAP11), 002 (new pulsotype 1274), 012 (new pulsotype NML-1235). Two of the six isolates belonging to ribotypes 143 and 133 were non-toxigenic. All toxigenic strains were sensitive to metronidazole and vancomycin. Regarding the clinical manifestation, diarrhea lasted an average of 11 days, ranging from 3 to 50 days and was often associated with mucus and/or blood. All six patients from whom the C. difficile was isolated had a chronic disease diagnosis, with these comorbidities as the main risk factors. Conclusion Our study enhances our understanding of the present epidemiological landscape of C. difficile-associated diarrhea (CDI) among children in northeastern Brazil, reveling a substantial CDI frequency of 30.4 %, with toxigenic strains detected in 76.4 % of cases, highlighting a higher prevalence compared to earlier Brazilian studies. In the globalized world, an understanding of disease-generating strains, the associated risk factors, clinical manifestation, and antimicrobial sensitivity has fundamental epidemiological importance and draws attention to preventive measures, allowing for more decisive action.

Infecciones por Clostridioides difficile en pediatría. La visión del laboratorio a partir del diagnóstico microbiológico / Clostridioides difficile infections in pediatrics. The view of the laboratory based on microbiological diagnosis

La infección por Clostridioides difficile (ICD) es la principal responsable de diarreas nosocomiales en adultos. En los últimos años se registró un aumento en la incidencia de la ICD en la población adulta que, en cambio, no fue bien caracterizado en pediatría. El objetivo de este trabajo es analizar los datos resultantes del diagnóstico microbiológico de ICD en el Hospital de Pediatría "Prof. Dr. Juan P. Garrahan". Materiales y métodos: se realizó un estudio retrospectivo observacional descriptivo que abarcó desde el 01/01/2018 hasta el 31/12/2021. El diagnóstico se realizó mediante enzimoinmunoensayo para glutamato deshidrogenasa (GDH) y toxinas en materia fecal (MF). Cuando sólo se detectó GDH, se realizó un cultivo toxigénico (CT) de la MF para la detección de toxinas in vitro. Se registraron: edad, sexo y procedencia de los pacientes y recurrencias de las ICD. Se efectuaron estudios de sensibilidad de 387 cepas de C. difficile a metronidazol (MTZ) y vancomicina (VAN). Resultados: en 6632 muestras (1764 pacientes) se registraron 649 estudios positivos (9,8%) (139 pacientes), la mayoría correspondieron a pacientes internados en áreas no críticas. Edad promedio: 7 años (7 ± 4,7). Sexo: 55% masculino. Recurrencias: 62 (45%). Positivos detectados mediante CT: 43%. Sensibilidad antibiótica: 100% a MTZ y 99,7% a VAN. Conclusión: Nuestra población presenta un bajo porcentaje de positividad. Se destaca el rendimiento del CT que permitió el diagnóstico de más de un tercio de los casos. MTZ y VANCO tuvieron excelente actividad in vitro frente a C. difficile (AU)

Clostridioides difficile infection (CDI) is the main cause of nosocomial diarrhea in adults. In recent years there has been an increase in the incidence of CDI in the adult population; however, CDI has not been well characterized in pediatrics. The aim of this study was to analyze the data resulting from the microbiological diagnosis of CDI at Hospital de Pediatría Prof. Dr. Juan P. Garrahan. Materials and methods: a retrospective, observational and descriptive study was conducted from 01/01/2018 to 12/31/2021. Diagnosis was made using enzyme immunoassay for glutamate dehydrogenase (GDH) and toxins in stools. When only GDH was detected, toxigenic culture (TC) of stools was performed for in vitro toxin detection. The age, sex and origin of patients and CDI recurrences were recorded. Sensitivity studies of 387 strains of C. difficile to metronidazole (MTZ) and vancomycin (VAN) were performed. Results: In 6,632 samples (1,764 patients), 649 positive results (9.8%) were recorded (139 patients), most of which corresponded to patients hospitalized in noncritical areas. Mean age: 7 years (7 ± 4.7). Sex: 55% male. Recurrences: 62 (45%). TC-positive results: 43%. Antibiotic sensitivity: 100% to MTZ and 99.7% to VAN. Conclusion: A low percentage of positivity was found in our population. The performance of TC was outstanding, allowing for the diagnosis of more than one third of the cases. MTZ and VANCO had excellent in vitro activity against C. difficile (AU)

Medicamentos antidepressivos estão associados a um risco aumentado de infecção hospitalar por Clostridioides difficile: um estudo populacional / Antidepressant medications are associated with increased risk of hospital-acquired clostridioides difficile infection: a population-based study

ABSTRACT Background: During the past decade, Clostridioides difficile infection (CDI) has become the most common cause of antibiotic-associated diarrhea. Several risk factors have been implicated. Scattered evidence about the association of CDI with antidepressant medications use exists in the literature so far. Therefore, we aim to investigate whether the risk of developing CDI is increased in hospitalized patients using antidepressant medications. Methods: Patients who were hospitalized were included in our cohort. We excluded individuals aged less than 18 years. A multivariate regression analysis was performed to calculate the risk of CDI accounting for potential confounders. Results: The risk of CDI in hospitalized patients was increased in individuals diagnosed with inflammatory bowel disease (OR: 4.44; 95%CI: 4.35-4.52), and in patients using clindamycin (OR: 1.55; 95%CI: 1.53-1.57), beta-lactam antibiotics (OR: 1.62; 95%CI: 1.60-1.64), PPI (OR: 3.27; 95%CI: 3.23-3.30), trazodone (OR: 1.31; 95%CI: 1.29-1.33), nortriptyline (OR: 1.25; 95%CI: 1.21-1.28), and mirtazapine (OR: 2.50; 95%CI: 2.46-2.54). After controlling for covariates, the risk of CDI was not increased in patients who were taking fluoxetine (OR: 0.94; 95%CI: 0.92-0.96). Conclusion: In contrary to fluoxetine; mirtazapine, nortriptyline, and trazodone were associated with increased risk of CDI in hospitalized patients.

RESUMO Contexto: Na última década, a infecção por Clostridioides difficile (ICD) tornou-se a causa mais comum de diarreia associada a antibióticos. Vários fatores de risco foram implicados. Existem evidências dispersas na literatura sobre a associação da ICD com o uso de medicamentos antidepressivos. Portanto, pretendemos investigar se o risco de desenvolver infecção adquirida na comunidade por Clostridioides difficile aumenta em pacientes que usam medicamentos antidepressivos. Métodos: Pacientes que foram hospitalizados foram incluídos em nossa coorte. Indivíduos com menos de 18 anos foram excluídos. Uma análise de regressão multivariada foi realizada para calcular o risco de ICD, considerando possíveis confusões. Resultados: O risco de ICD em pacientes hospitalizados foi maior em indivíduos diagnosticados com doença inflamatória intestinal (OR: 4,44; IC95%: 4,35-4,52) e em pacientes que usavam clindamicina (OR: 1,55; IC95%: 1,53-1,57), antibióticos beta-lactâmicos (OR: 1,62; IC95%: 1,60-1,64), PPI (OR: 3,27; IC95%: 3,23-3,30), trazodona (OR: 1,31; IC95%: 1,29-1,33), nortriptilina (OR: 1,25; IC95%: 1,21-1,28) e mirtazapina (OR: 2,50; IC95%: 2,46-2,54). Depois de controlar as covariáveis, o risco de ICD não aumentou em pacientes que estavam tomando fluoxetina (OR: 0,94; IC95%: 0,92-0,96). Conclusão: Em contrário à fluoxetina; mirtazapina, nortriptilina e trazodona foram associados a um risco aumentado de ICD em pacientes hospitalizados.

Characterization of a Clostridioides difficile ST-293 isolate from a recurrent infection in Argentina

Resumen Clostridioides difficile es un patógeno esporulado oportunista responsable de diarrea asociada a antibióticos en humanos. C. difficile produce 2 toxinas principales: TcdAy TcdB, además de la toxina binaria (CDT), también asociada a la virulencia. Este estudio buscó caracterizar el aislamiento ALCD3, involucrado en un episodio de recurrencia de una infección nosocomial. La caracterización molecular mostró que dicho aislamiento pertenece al toxinotipo 0/v y el análisis por MLST demostró un perfil alélico adk:91, atpA:1, dxr:2, glyA: 1, recA:27, sodA: 1 y tpi:1, lo cual corresponde al ST293 (MLST clado 1). Durante el crecimiento, el aislamiento ALCD3 mostró un incremento temprano de la tasa de esporulación y valores máximos de formas termorresistentes luego de 2 días de incubación. Tanto la cinética de esporulación como la producción de formas termorresistentes fueron más rápidas en el aislamiento ALCD3 que en la cepa de referencia VPI 10463. La germinación en presencia del germinante natural taurocolato fue más rápida en el aislamiento ALCD3 que en la cepa VPI 10463, lo que indica que aquel comienza la hidrólisis del córtex antes. También, el co-germinante glicina indujo una rápida liberación de ácido dipicolínico en ALCD3. Estos hallazgos indican que el aislamiento ALCD3 es particularmente eficiente en la esporulación y en la germinación. El presente trabajo representa el primer informe de la circulación de C. difficile ST293 en Argentina. La habilidad del aislamiento ALCD3 para producir toxinas y su alta capacidad de esporulación/germinación son características claves compatibles con un alto potencial de diseminación e inducción de infecciones recurrentes.

Abstract Clostridioides difficile is an opportunistic spore-forming pathogen responsible for antibiotic-associated diarrhea in humans. C. difficile produces two main toxins: TcdA and TcdB as well as a third toxin named binary toxin (CDT) that is also involved in virulence. The present study aimed at characterizing the C. difficile isolate ALCD3 involved in a relapse episode of nosocomial infection. Molecular characterization showed that isolate ALCD3 belongs to tox-inotype 0/v and the MLST analysis demonstrated allelic profile adk:91, atpA:1, dxr:2, glyA: 1, recA:27, sodA: 1 and tpi:1 which corresponds to ST293 (MLST clade: 1). During growth, isolate ALCD3 showed an early increase in the sporulation ratio as well as maximal values of heat resis-tant forms after 2 days of incubation. Both sporulation kinetics and production of heat resistant forms were faster for isolate ALCD3 than for the reference strain VPI 10463. Germination in the presence of the natural germinant taurocholate was faster for isolate ALCD3 than for strain VPI 10463, which indicates that isolate ALCD3 starts cortex hydrolysis earlier than strain VPI 10463. Furthermore, the co-germinant glycine, induces rapid release of dipicolinic acid (DPA) in isolate ALCD3. These findings indicate that isolate ALCD3 is particularly efficient in both sporulation and germination. The present work represents the first report of the circulation of C. difficile ST293 in Argentina. The ability of isolate ALCD3 to produce toxins and its high sporulation/germination capacity are key features compatible with a microorganism with high dissemination potential and the possibility of inducing recurrent infections.

Trasplante de microbiota fecal como alternativa de tratamiento por infecciones de clostridoides difficile / Fecal microbiota transplantation as a treatment alternative for clostridoides difficile infections / Transplante de microbiota fecal como tratamento alternativo para infecções clostridioides difficile

La infección por Clostridioides difficile es una amenaza para la salud pública, está asociada a la atención médica, cuya complicación más frecuente es la infección recurrente, con tasas de hasta el 60% después del tercer episodio. Las opciones de tratamiento para la recurrencia de esta infección son limitadas. Una gran paradoja es tratar una infección asociada a antibióticos con más antibióticos, por ello, la piedra angular en el manejo de esta infección es la restauración de la microbiota intestinal mediante el trasplante de microbiota fecal. Objetivo. Determinar la eficacia y seguridad del trasplante de microbiota fecal para el tratamiento de la infección recurrente por Clostridioides difficile. Metodología. Se realizó una revisión bibliográfica narrativa de la literatura científica en las bases de datos PubMed y Cochrane Library empleando los Descriptores en Ciencias de la Salud (DeCS) y Medical Subject Headings (MeSH), junto con los operadores booleanos "AND/Y", "OR/O"; donde se recopilaron los estudios que cumplieron con los criterios de inclusión. Conclusión. Se concluyó que el trasplante de microbiota fecal en la infección recurrente por Clostridioides difficile es un tratamiento eficaz y seguro, con eventos adversos mínimos, aunque la seguridad a largo plazo no está bien establecida.

Clostridioides difficile infection is a public health threat, is associated with health care, the most common complication of which is recurrent infection, with rates of up to 60% after the third episode. Treatment options for recurrence of this infection are limited. A great paradox is to treat an antibiotic-associated infection with more antibiotics; therefore, the cornerstone in the management of this infection is the restoration of the intestinal microbiota by fecal microbiota transplantation. Objective. To determine the efficacy and safety of fecal microbiota transplantation for the treatment of recurrent Clostridioides difficile infection. Methodology. A narrative bibliographic review of the scientific literature was carried out in the PubMed and Cochrane Library databases using the Health Sciences Descriptors (DeCS) and Medical Subject Headings (MeSH), together with the Boolean operators "AND/Y", "OR/O"; where the studies that met the inclusion criteria were collected. Conclusion. It was concluded that fecal microbiota transplantation in recurrent Clostridioides difficile infection is an effective and safe treatment, with minimal adverse events, although long-term safety is not well established.

A infecção por Clostridioides difficile é uma ameaça à saúde pública associada ao cuidado com a saúde, cuja complicação mais comum é a infecção recorrente, com taxas de até 60% após o terceiro episódio. As opções de tratamento para infecções recorrentes são limitadas. Um grande paradoxo é tratar uma infecção associada a antibióticos com mais antibióticos, portanto, a pedra fundamental no manejo desta infecção é a restauração da microbiota intestinal através do transplante da microbiota fecal. Objetivo. Determinar a eficácia e segurança do transplante de microbiota fecal para o tratamento de infecções recorrentes por Clostridioides difficile. Metodologia. Uma revisão bibliográfica narrativa da literatura científica foi realizada nas bases de dados da Biblioteca PubMed e Cochrane utilizando os Descritores de Ciências da Saúde (DeCS) e os Títulos de Assuntos Médicos (MeSH), juntamente com os operadores booleanos "AND/Y", "OR/O"; onde foram compilados os estudos que preenchiam os critérios de inclusão. Conclusão. Concluiu-se que o transplante de microbiota fecal em infecção recorrente por Clostridioides difficile é um tratamento eficaz e seguro com o mínimo de eventos adversos, embora a segurança a longo prazo não esteja bem estabelecida.

Clostridioides difficile: Characterization of the circulating toxinotypes in an Argentinean public hospital / Clostridioides difficile: caracterización de los toxinotipos circulantes en un hospital público de Argentina

Abstract Clostridioides difficile is a spore-forming anaerobe microorganism associated to nosocomial diarrhea. Its virulence is mainly associated with TcdA and TcdB toxins, encoded by their respective tcdA and tcdB genes. These genes are part of the pathogenicity locus (PaLoc). Our aim was to characterize relevant C. difficile toxinotypes circulating in the hospital setting. The tcdA and tcdB genes were amplified and digested with different restriction enzymes: EcoRI for tcdA; HincII and AccI for tcdB. In addition, the presence of the cdtB (binary toxin) gene, TcdA and TcdB toxins by dot blot and the cytotoxic effect of culture supernatants on Vero cells, were evaluated. Altogether, these studies revealed three different circulating toxinotypes according to Rupnik's classification: 0, I and VIII, being the latter the most prevalent one. Even though more studies are certainly necessary (e.g. sequencing analysis), it is worth noting that the occurrence of toxinotype I could be related to the introduction of bacteria from different geographical origins. The multivariate analysis conducted on the laboratory values of individuals infected with the most prevalent toxinotype (VIII) showed that the isolates associated with fatal outcomes (GCD13, GCD14 and GCD22) are located in regions of the biplots related to altered laboratory values at admission. In other patients, although laboratory values at admission were not correlated, levels of urea, creatinine and white blood cells were positively correlated after the infection was diagnosed. Our study reveals the circulation of different toxinotypes of C. difficile strains in this public hospital. The variety of toxinotypes can arise from pre-existing microorganisms as well as through the introduction of bacteria from other geographical regions. The existence of microorganisms with different pathogenic potential is relevant for the control, follow-up, and treatment of the infections.

Resumen Clostridioides difficile es un anaerobio esporulado que se asocia con episodios de diarreas hospitalarias. Su virulencia se encuentra vinculada, principalmente, a las toxinas TcdA y TcdB, codificadas por sus respectivos genes, tcdA y tcdB, que son parte de un locus de patogenicidad (PaLoc). Nuestro objetivo fue caracterizar los toxinotipos de C. difficile circulantes en un hospital público. Los genes tcdA y tcdB fueron amplificados y digeridos con diferentes enzimas de restricción: EcoRI para tcdA; HincII y AccI para tcdB. Además, se evaluó la presencia de cdtB (gen de la toxina binaria B) y de las toxinas A y B (por dot blot), así como el efecto citotóxico de sobrenadantes de cultivo sobre células Vero. En conjunto, estos estudios revelaron tres toxinotipos circulantes según la clasificación de Rupnik: 0, I y VIII; el más prevalente fue el último. Aunque son necesarios más estudios (ej., secuenciación), es interesante notar que la presencia del toxinotipo I podría estar relacionada con la introducción de bacterias de diferente origen geográfico. En los pacientes infectados con el toxinotipo VIII, el análisis multivariante de los resultados de laboratorio mostró que los aislamientos asociados a decesos (GCD13, GCD14 y GCD22) estaban situados en regiones de los biplots relacionados con valores de laboratorio alterados al momento de la internación. En los otros pacientes, aunque no se observó correlación entre los valores de laboratorio al momento de la internación y la evolución clínica, los niveles de urea, creatinina y recuento de glóbulos blancos estuvieron correlacionados positivamente entre sí una vez diagnosticada la infección. Nuestro estudio revela la circulación de diferentes toxinotipos de C. difficile en un mismo hospital público. La variedad de toxinotipos puede originarse a partir de microorganismos preexistentes en la región, así como también por la introducción de bacterias provenientes de otras regiones geográficas. La existencia de microorganismos con diferente potencial patogénico es relevante para el control, el seguimiento y el tratamiento de las infecciones.

The fliL gene significantly affects the motility and sporulation abilities of Clostridioides difficile / 生物工程学报

Flagella are the main motility structure of Clostridioides difficile that affects the adhesion, colonization, and virulence of C. difficile in the human gastrointestinal tract. The FliL protein is a single transmembrane protein bound to the flagellar matrix. This study aimed to investigate the effect of the FliL encoding gene flagellar basal body-associated FliL family protein (fliL) on the phenotype of C. difficile. The fliL gene deletion mutant (ΔfliL) and its corresponding complementary strains (: : fliL) were constructed using allele-coupled exchange (ACE) and the standard molecular clone method. The differences in physiological properties such as growth profile, antibiotic sensitivity, pH resistance, motility, and spore production ability between the mutant and wild-type strains (CD630) were investigated. The ΔfliL mutant and the : : fliL complementary strain were successfully constructed. After comparing the phenotypes of strains CD630, ΔfliL, and : : fliL, the results showed that the growth rate and maximum biomass of ΔfliL mutant decreased than that of CD630. The ΔfliL mutant showed increased sensitivity to amoxicillin, ampicillin, and norfloxacin. Its sensitivity to kanamycin and tetracycline antibiotics decreased, and the antibiotic sensitivity partially returned to the level of CD630 strain in the : : fliL strain. Moreover, the motility was significantly reduced in the ΔfliL mutant. Interestingly, the motility of the : : fliL strain significantly increased even when compared to that of the CD630 strain. Furthermore, the pH tolerance of the ΔfliL mutant significantly increased or decreased at pH 5 or 9, respectively. Finally, the sporulation ability of ΔfliL mutant reduced considerably compared to the CD630 strain and recovered in the : : fliL strain. We conclude that the deletion of the fliL gene significantly reduced the swimming motility of C. difficile, suggesting that the fliL gene is essential for the motility of C. difficile. The fliL gene deletion significantly reduced spore production, cell growth rate, tolerance to different antibiotics, acidity, and alkalinity environments of C. difficile. These physiological characteristics are closely related to the survival advantage in the host intestine, which is correlated with its pathogenicity. Thus, we suggested that the function of the fliL gene is closely related to its motility, colonization, environmental tolerance, and spore production ability, which consequently affects the pathogenicity of C. difficile.

Etiology and prognostic factors of necrotizing enterocolitis in infants after neonatal period with hematochezia / 中国小儿急救医学

Objective:To analyze the etiology and prognostic factors of necrotizing enterocolitis(NEC) in infants after neonatal period with hematochezia.Methods:The clinical data of 62 infants older than 28 days with NEC and hematochezia diagnosed at Beijing Children′s Hospital, Capital Medical University from January 2016 to December 2021 were retrospectively analyzed, summarizing the etiology of NEC in this age group and analyze the factors affecting the prognosis of NEC.According to IgE detection results of food allergens, the infants were divided into milk protein positive group and milk protein negative group.According to the absolute value level of peripheral blood eosinophils, they were divided into increased eosinophils group(≥0.5×10 9/L) and normal eosinophils group(<0.5×10 9/L). They were divided into three groups according to co-infection: NEC group(no co-infection), NEC+ clostridium difficile associated diarrhea(CDAD) group, and NEC+ other infection group(salmonella infection or sepsis). According to different feeding methods, they were divided into normal amino acid group(osmotic pressure 310 mOsm/L), diluted amino acid group(osmotic pressure 233 mOsm/L), and deep hydrolysis group(osmotic pressure 185 mOsm/L). The relief time of clinical symptoms, the recovery time of intestinal gas accumulation, feeding time to achieve physiological requirements, and the length of hospital stay in each group were compared. Results:Among 62 cases, there were 27 males and 35 females.The median age of onset was 1.4(1.2, 2.3) months.The median birth weight was 3.2(2.9, 3.4)kg.Full-term infants accounted for 87.1%.Cesarean accounted for 62.9%.Fifty-three patients(85.5%)had allergic symptoms.Thirteen patients(21.0%)had family history of allergy.Cow milk protein allergy was diagnosed in 29 cases.Thirty-two cases(51.6%) had elevated peripheral blood eosinophils.The hospitalization time of milk protein positive group was longer than that of negative group( P=0.047). The clinical remission rate after hypoallergenic formula feeding for 1 day of increased eosinophils group was higher than that of normal eosinophil group(100.0% vs.65.0%, P=0.002). Ten patients(16.1%)were complicated with clostridium difficile infection, two patients(3.2%) with salmonella enteritis, and four patients(6.5%) with sepsis.Both the hospital stay and feeding time to achieve physiological requirements of NEC+ other infection group were longer than the other two groups( P<0.05). NEC+ CDAD group had a higher rate of repeated hospitalizations(40.0%, P=0.004). The mean recovery time of intestinal gas accumulation was(4.5±2.9)days.After(3.9±3.0)days, hypoallergenic formula feeding started.After one day of feeding, the clinical remission rate was 79.0%.The average time to achieve physiological requirements was(5.8±3.2)days.The clinical symptom relief time of diluted amino acid group was shorter( P=0.006), but there was no statistical difference in feeding time to achieve physiological requirements and hospitalization time between each group( P>0.05). Conclusion:Cow′s milk protein allergy and infection(especially CDAD)are closely related to the occurrence and development of NEC after neonatal period with hematochezia.The administration of diluted amino acid-based formulae close to the osmotic pressure of breast milk and targeted anti-infective therapy could shorten the clinical remission time of NEC and reduce the risk of repeated hospitalization.

Comparison of biological characteristics of major epidemic strains of Clostridium difficile from nosocomial infectious diarrhea / 中华检验医学杂志

Objective:This work aims to investigate the virulence features, spore formation and the resistance mechanisms of major sequence types (STs) of clinical Clostridium difficile isolates from nosocomial infectious diarrhea. Methods:Clostridium difficile isolates were prospectively collected from 816 loose stool samples of in patients with antibiotic associated diarrhea at the Beijing Friendship Hospital of Capital Medical University from September 2017 to September 2019. The main ST types ST81 (26 strains), ST8 (15 strains) and ST42 (14 strains) of C. difficile were used as experimental strains. The polymerase chain reaction (PCR) and enzyme-linked immunoassay (ELISA) were performed to detect toxin genes and toxin production of different C. difficile ST types, respectively. The count of the colony forming units (CFU) of the strains as conducted by using the brain-heart infusion (BHI) agar plates. The antimicrobial resistance patterns of the strains to eleven kinds of antibiotics were determined by agar dilution method. The antimicrobial resistance genes: gyrA, gyrB and ermB were amplified and sequenced from the stains. Mutations in the resistance genes were analyzed by sequencing. Measure data was compared by Kruskal Wallis Test, differences in the resistance rates in three group were compared using Fisher exact test. Results:ST81 strains were identified as the tcdA-tcdB+/ cdtA-cdtB-toxin type, ST8 and ST42 strains belonged to tcdA+tcdB+/ cdtA-cdtB-toxin type. The toxin production of ST42 strains (41.9) were higher than ST8 (2.4) and ST81 groups (0.83) (all P<0.001). The number of spore quantities of ST81, ST8 and ST42 strains were 494×10 5CFU/ml, 160×10 5CFU/ml and 166×10 5CFU/ml, respectively. The spore quantities of ST81 strains were much higher than that of ST81 and ST42 strains (all P<0.001). From the in vitro susceptibility test, 100% (26/26) ST81 strains were featured as multi-drug resistant (MDR), and they were resistant to moxifloxacin, ceftriaxone, erythromycin and clindamycin. The resistance rates of ST8 strain to moxifloxacin, erythromycin and clindamycin were 9/15, 11/15 and 11/15, respectively. ST81 strains had higher resistance rates to moxifloxacin, clindamycin and erythromycin, compared to ST8 strains ( P=0.001, P=0.005 and P=0.005). All ST42 strains were susceptible to ceftriaxone and 3/14 ST42 strains were resistant to moxifloxacin. ST81 strains had higher resistance rates to ceftriaxone and moxifloxacin than the ST42 strains (both P<0.001). The positive rate of ermB in ST81 strains (100%, 26/26) were higher the ST8 strains (11/15) ( P<0.005). Amino acid mutation analysis showed that ST81and ST8 stains had one amino acid substitution in both GyrA and GyrB, but the amino acid substitutions were different in GyrB between two ST types. ST81 strains had two point-mutations: Thr82 replaced by Ile in GyrA, and Asp426 replaced by Val in GyrB. ST8 strains had point-mutation: Thr82 replaced by Ile in GyrA; Asp426 replaced by Asn in GyrB. For ST42 strains, Thr82 was replaced by Ile in GyrA. Conclusions:ST81 and ST42 strains were MDR. ST81 had higher spore ability, whereas ST42 strains had more virulence. ST81 strains and most of ST8 strains had high level of fluoroquinolones resistance. It is important to supervise persistently these three ST genotypes to prevent further dissemination.

Design, synthesis and biological evaluation of 8-hydroxyquinoline derivatives as potential clostridium difficile antibiotics / 药学实践与服务

Objective To find a more effective alternative therapy for antibiotic therapy and fecal microbiota transplantation in current primary treatment of clostridioides difficile infection (CDI) because of the high recurrence rate. Methods A series of 8-hydroxyquinoline derivatives were designed and synthesized based on 8-hydroxyquinoline scarffold. Results The activity test against C. difficile showed that most of the molecules exhibited good antibacterial activity against C. difficile, and compound 6f showed attractive anti-C. difficile activity. Conclusion A new type of 8-hydroxyquinoline derivatives with anti-clostridium difficile was found, which could be used as good lead compounds for further development.

Prokaryotic expression,purification and activity of CamA protein with methylase activity from Clostridiodies difficile / 中国生物制品学杂志

@#Objective To express CamA(Clostridiodies difficile adenine methltransferase A,CamA)protein with methylase activity in prokaryotic expression system.Methods The gene sequence of CamA protein of the standard strain of C.difficile1870 was amplified by PCR,cloned into plasmid pGEX-4T-1-MBP,transformed into E.coli HB101 and induced by 1 mmol/L IPTG to express the recombinant target protein. After purification with Amylose Resin,CamA protein was digested by tobacco etch virus(TEV)protease,and verified for its methylase activity using MTase-Glo~(TM)Methyltransferase Assay in vitro.Results PCR sequencing showed that the cloned CamA gene sequence was correct,in which no base mutation occurred. The recombinant expression plasmid pGEX-4T-1-MBP-CamA was digested by EcoRⅠand BamHⅠ,which showed that 1 731 bp of CamA gene was connected to the vector plasmid. The relative molecular mass of the recombinant protein was about 108 800(with 1 MBP tag),and the purity was over 90% after purified with Amylose Resin. Under the condition of20 μmol/L DNA and 20 μmol/L SAM at room temperature for 30 min,0. 5 μg CamA produced SAH at a concentration of about 101. 60 nmol/L and the enzyme activity was(0. 339 ± 0. 027)U/mg.Conclusion The CamA protein of C.difficile has been successfully expressed and purified with methylase activity,which lays a foundation of further study on the function of CamA and its role in the occurrence,development and treatment of C.difficile infection.

Status and challenge of vaccine research for Clostridiodes difficile in clinical trials / 中国生物制品学杂志

@#Clostridiodes difficile(C.difficile)is the most common causative agent of antibiotic-associated diarrhea(ADD)in the world. In recent years,with the emergence of highly resistant and virulent strains,the outbreaks of C.difficile infection have occurred around the world. The incidence,recurrence and mortality of C.difficile infection are on the rise worldwide,and bring great challenges to clinical treatment. Pathogenic strains mainly produce two homologous glycosylation toxins A and B,which can cause symptoms ranging from diarrhea to highly lethal toxic megacolon. In view of the malignant consequences caused by C.difficile infection,disease prevention is still an important way worth exploring. Until now there is no approved vaccine against C.difficile. Therefore,this review assessed the status and challenge of clinical trials of vaccine research for C.difficile.

Management of diarrhea after kidney transplantation / 器官移植

Diarrhea is a frequent complication after kidney transplantation, which is a common clinical manifestation of prevalent diseases following multiple types of organ transplantation. The common causes of diarrhea after kidney transplantation include adverse reactions of immunosuppressants, infectious diseases and de novo postoperative inflammatory bowel disease, etc. Diarrhea could seriously affect the quality of life of kidney transplant recipients, and may lead to allograft dysfunction or even death of recipients. Because the causes of diarrhea after kidney transplantation are complicated and probably overlap with each other, along with individual differences among recipients, the etiological diagnosis and targeted treatment of diarrhea after kidney transplantation should follow the principles of gradual and phased treatment. In this article, the epidemiology and harm, common causes and management strategies of diarrhea after kidney transplantation were summarized, aiming to deepen the clinicians' understanding and enhance the diagnosis and treatment levels of diarrhea after kidney transplantation, thereby improving the quality of life and prognosis of kidney transplant recipients.

Caracterización epidemio-molecular de la infección por Clostridioides difficile en pacientes hospitalizados con cuadro diarreico en instituciones de salud. 2019

La infección por Clostridioides difficile es una de las principales causas de diarrea nosocomial en hospitales del mundo, asociada a antibióticos de amplio espectro. Estudio descriptivo, retrospectivo, de corte transverso, de tipo censal. Se estudiaron 281 muestras de pacientes hospitalizados con la infección, se analizaron características socio-demográficas, clínicas y se caracterizó molecularmente al patógeno. Como resultado, se obtuvieron pacientes con la infección con una mediana de edad de 64 años siendo el 61,5 % del sexo masculino. El promedio de presentación del cuadro diarreico fue de 5 días, con tratamiento antimicrobiano de 8 días e internación de 15 días. El 94% tuvo tratamiento antimicrobiano previo, y el 6% estuvo expuesto a algún factor de riesgo. Los antimicrobianos más utilizados solos o en combinación fueron betalactámicos, fluoroquinolonas, vancomicina y carbapenémicos. Las áreas de internación con mayor frecuencia de presentación de la infección fueron las unidades de Clínica Médica, Traumatología, Geriatría y Unidad de Terapia Intensiva. La prevalencia de C. difficile toxigénico fue de 14%, y de esta frecuencia el 100% presentó toxinas TcdA y TcdB, con ausencia de toxinas binarias y deleción del gen tcdC. Se constató la presencia grupos clonales en la misma unidad de internación y misma institución de salud. El 100% de las cepas resultaron susceptibles a los antibióticos de elección para la infección. La prevalencia de la infección y presencia de perfiles clonales detectadas revelan la necesidad de un mejoramiento en el sistema de control de infecciones, así como del fortalecimiento y vigilancia de la resistencia antimicrobiana.

Clostridioides difficile infection is one of the main causes of nosocomial diarrhea in hospitals worldwide, associated with broad-spectrum antibiotics. Descriptive, retrospective, cross-sectional, census-type study. Two hundred eighty-one samples from patients hospitalized with the infection were studied, sociodemographic and clinical characteristics were analyzed and the pathogen was characterized molecularly. As a result, patients with the infection had a median age of 64 years and 61.5% male. The average presentation of diarrhea was 5 days, antimicrobial treatment 8 days and hospitalization 15 days. Ninety four percent had previous antimicrobial treatment, and 6% were exposed to some risk factor. The most commonly used antimicrobials alone or in combination were beta-lactams, fluoroquinolones, vancomycin, and carbapenems. The hospitalization areas with the highest frequency of presentation of the infection were the Clinical Medicine, Traumatology, Geriatrics and Intensive Care Unit units. The prevalence of toxigenic C. difficile was 14%, and of this frequency, 100% presented TcdA and TcdB toxins, with the absence of binary toxins and deletion of the tcdC gene. The presence of clonal groups was verified in the same hospitalization unit and the same health institution. All the strains were susceptible to the antibiotics of choice for the infection. The prevalence of infection and the presence of clonal profiles detected reveal the need for improvement of the infection control system, as well as of the strengthening and surveillance of antimicrobial resistance.

A case-control study of Clostridioides difficile symptomatic infections in a pediatric cancer hospital / Um estudo caso-controle de infecções sintomáticas por Clostridioides difficile em um hospital oncológico pediátrico

Abstract Objective: The aim of this study was to analyze and identify documented infections and possible risk factors for Clostridioides difficile infections in children with cancer. Methods: This is a retrospective case-control study, carried out in a pediatric cancer hospital, covering the years 2016-2019. Matching was performed by age and underlying disease, and for each case, the number of controls varied from 1 to 3. Logistic regression models were used to assess risk factors. Results: We analyzed 63 cases of documented infection by C. difficile and 125 controls. Diarrhea was present in all cases, accompanied by fever higher than 38°C in 52.4% of the patients. Mortality was similar among cases (n=4; 6.3%) and controls (n=6; 4.8%; p=0.7). In all, 71% of patients in the case group and 53% in the control group received broad-spectrum antibiotics prior to the infection. For previous use of vancomycin, the Odds Ratio for C. difficile infection was 5.4 (95% confidence interval [95%CI] 2.3-12.5); for meropenem, 4.41 (95%CI 2.1-9.2); and for cefepime, 2.6 (95%CI 1.3-5.1). For the antineoplastic agents, the Odds Ratio for carboplatin was 2.7 (95%CI 1.2-6.2), melphalan 9.04 (95%CI 1.9-42.3), busulfan 16.7 (95%CI 2.1-134.9), and asparaginase 8.97 (95%CI 1.9-42.9). Conclusions: C. difficile symptomatic infection in children with cancer was associated with previous hospitalization and the use of common antibiotics in cancer patients, such as vancomycin, meropenem, and cefepime, in the last 3 months. Chemotherapy drugs, such as carboplatin, melphalan, busulfan, and asparaginase, were also risk factors.

RESUMO Objetivo: Analisar e identificar infecções documentadas e possíveis fatores de risco para infecções por Clostridioides difficile em crianças com câncer. Métodos: Estudo retrospectivo caso-controle em um hospital pediátrico oncológico, que abrangeu os anos de 2016-2019. O pareamento foi realizado por idade e doença de base e, para cada caso, o número de controles variou de um a três. Modelos de regressão logística foram utilizados para avaliar os fatores de risco. Resultados: Analisamos 63 casos de infecção documentados por C. difficile e 125 controles. A diarreia esteve presente em todos os casos, acompanhada de febre acima de 38°C em 52,4% dos pacientes. A mortalidade foi semelhante entre casos (n=4, 6,3%) e controles (n=6, 4,8%; p=0,7). No grupo caso, 71% dos pacientes e, no grupo controle, 53% deles receberam antibióticos de amplo espectro antes da infecção. Para uso prévio de vancomicina, a Odds Ratio para infecção por C. difficile foi de 5,4 (intervalo de confiança [IC95%] 2,3-12,5); para meropenem, 4,41 (IC95% 2,1-9,2) e, para cefepima, 2,6 (IC95% 1,3-5,1). Para os agentes antineoplásicos, a razão de chances para carboplatina foi de 2,7 (IC95% 1,2-6,2), para melfalano de 9,04 (IC95% 1,9-42,3), para bussulfano de 16,7 (IC95% 2,1-134,9) e, para asparaginase, de 8,97 (IC95% 1,9-42,9). Conclusões: A infecção sintomática por C. difficile em crianças com câncer associou-se à internação prévia e ao uso de antibióticos como vancomicina, meropenem e cefepime nos últimos três meses. Os quimioterápicos carboplatina, melfalano, bussulfano e asparaginase também foram fatores de risco.