Respuesta inmune disfuncional en pacientes con COVID-19. ¿Qué nos dice la evidencia? / Dysfunctional immune response in COVID-19 patients. What does the evidence tell us?

In December 2019 a novel coronavirus (SARS-CoV-2) was identified in Wuhan, China, and became rapidly the worst pandemic in 100 years. Coronaviruses are respiratory viruses that can cause diseases ranging from mild to fatal lower respiratory tract infections. In a fraction of the affected patients, coronavirus disease 2019 (COVID-19), caused by SARS-CoV-2, can lead to acute respiratory distress syndrome (ARDS) and intensive care unit (ICU) admission, both associated with high mortality. To date, the existing evidence suggests a leading role of the immune system in the pathogenesis of severe COVID-19, including mechanisms associated with hyperinflammation, immune evasion, cytokine release syndrome, depletion of functional T cells, and ineffective humoral immunity. Here we discuss the current evidence regarding these findings.

Rol de la cirugía en el manejo de la infección invasora por Saprochaete capitata / Role of surgery in Saprochaete capitata (S. capitata) sepsis in a patient with acute myeloid leukemia

Saprochaete capitata (S. capitata) fungal sepsis is a severe condition with a clinical presentation that is similar to other yeast originated fungal sepsis. It is observed in patients with hematological malignancies such as acute myeloid leukemia and neutropenia. We report a 23 year old male presenting with cough, fever and malaise. A bone marrow biopsy led to the diagnosis of acute myeloid leukemia. During the first cycle of chemotherapy the patient presented fever: blood cultures were positive for Klebsiella pneumoniae. Despite antimicrobial treatment, fever persisted; a computed tomography showed a focal splenic lesion; a left exudative pleural effusion appeared. A Matrix Assisted Laser Desorption Ionization-Time of Flight mass spectrometry identified the presence of S. capitata. After multiple antifungal treatments and pleural cavity cleansing by means of videothoracoscopy and laparoscopic splenectomy, the infection resolved and the patient completed his chemotherapy.

Neutropenia febril asociada a LES: reporte de un caso clínico / Systemic lupus erythematosus-associated febrile neutropenia: a case report

Introducción: Fiebre de Origen Desconocido (FOD) es una entidad clínica poco prevalente y amplio es el repertorio patologías conocidas como causales. Caso clínico. Se describe el caso de una mujer de 43 años, hipertensión arterial y "sífilis" tratada en 1994. Dos meses con Síndrome Febril Prolongado, baja de peso, poliartritis y compromiso del estado general progresivo, vómitos y diarrea. Destacaba en el examen físico temperatura axilar de 39°C, candidiasis oral, evidentemente enflaquecida y sensibilidad difusa del abdomen sin signos de alarma. Estudio revelo neutropenia febril y parámetros inmunológicos alterados, compatibles con Lupus Eritematoso Sistémico. Discusión.

Síndrome hemolítico urémico asociado a infección intestinal por Escherichia coli productora de shigatoxina (STEC) en pacientes chilenos: aspectos clínicos y epidemiológicos / Hemolytic uremic syndrome associated to shigatoxin producing Escherichia coli in Chilean children: clinical and epidemiological aspects

Clinical and epidemiological aspects of shigatoxin producing E. coli (STEC) infections and hemolytic uremic syndrome (HUS) are reviewed. Surveillance results from 14 sentinel centers during 2000-2002 showed a mean incidence rate of 3.4 HUS cases per 100.000 children, with the highest incidence in the 6 to 28 month age group. Disease is endemic with summer peaks. Between 1988 and 2002 we obtained the clinical characteristics of a group of 119 HUS children with the following results: mean age 16 months, bloody diarrhea 57.8 percent, no previous diarrhea 9 percent, 60 percent received antibiotics, 72 percent had oligoanuria, 53 percent required dialysis, 15 percent had seizures and 31 percent had dizziness; mortality was 3 percent. Four foodborne outbreaks have been detected in Santiago, two outbreaks occurred in household settings, one in a Day Care Center and one in a Neonatal Unit. Recommendations for diagnosis, treatment and prevention of STEC infections, including potential vaccines are discussed.

Se revisan y actualizan aspectos clínicos y epidemiológicos de las infecciones por Escherichia coli productora de shigatoxina (STEC), y el síndrome hemolítico urémico (SHU). Se incluyen resultados de una vigilancia de SHU en 14 centros centinelas (2000-2002), que mostró una incidencia promedio de 3,4 casos por 100.000 niños, 78 por ciento) en el grupo de 6 a 48 meses. Esta vigilancia reflejó una situación endémica, con aumento en verano. Se analiza la observación clínica protocolizada de 119 pacientes con SHU hospitalizados en la Región Metropolitana (RM) (1988 y 2002). Edad promedio: 16 meses. El 578 por ciento> tenía diarrea con sangre, 9 por ciento> no tenía diarrea previa, 60 por ciento> recibió antibacterianos, 72 por ciento> presentó oligoanuria y 53 por ciento> necesitó diálisis. El 31 por cientoo tuvo compromiso de conciencia y 15 por cientoo presentó convulsiones. Letalidad 3 por ciento. Se analizan brotes de STEC asociados a alimentos ocurridos en la RM en el hogar (2), un jardín infantil (1) y en un servicio de neonatología (1). Finalmente, se entregar recomendaciones para el manejo clínico y prevención, se revisan los criterios diagnósticos, nuevas estrategias terapéuticas y progresos en el desarrollo de vacunas.

Cambios en la sensibilidad antibiótica de E. Coli en mujeres con infección urinaria baja ambulatoria en un período de 10 años / Change in E. Coli antibiotic therapy resistance in female urinary tract infections in the last 10 years

La infección urinaria constituye la infección bacteriana más común, siendo los bacilos gram negativos(E. coli, P. mirabilis, Klebsiella) los patógenos más frecuentes. Esta enfermedad pese a los nuevos conocimientos tanto en factores relacionados con el huésped cómo en los relacionados con la biología de las bacterias, aún nos enfrenta a numerosos problemas no resueltos, cómo son la resistencia a los antibióticos y la recurrencia. La resistencia, de los patógenos, a los agentes antimicrobianos es un problema muy importante para la elección deun tratamiento de primera línea, por lo que nos parece necesario conocer sus cambios. El objetivo de este estudio es evaluar los cambios experimentados por la susceptibilidad de la E. Coli a los antibióticos de uso frecuente, en pacientes de consulta ambulatoria con ITU baja no complicada, en un período de 10 años. Realizamos unarevisión retrospectiva de los antecedentes, urocultivos y antibiograma de pacientes de sexo femenino que consultaron en nuestro centro en los años 1996 y 2005. Se registró la edad, bacteria y antibiograma de aquellas con urocultivos positivos, comparando las variaciones producidas en este período de tiempo. Se utilizó la prueba de Chi cuadrado para comparar la sensibilidad antibiótica. En el año 1996, durante el período enero a septiembre, se registraron 242 pacientes con urocultivos positivos, con una edad promedio de 46 años. En el 91,3 por ciento la bacteria responsable fue Escherichia coli. Durante el mismo período en el año 2005 registramos 296 pacientes con urocultivos positivos, con edad promedio de 52 años y Escherichia coli en el 88,5 por ciento. La resistencia de E. Coli a cotrimoxazol, sulbactam-ampicilina, Ac. Pipemídico, cefotaxima y cefradina aumentó significativamente. Por el contrario la resistencia a gentamicina disminuyó significativamente. El ciprofloxacino, norfloxacino, nitrofurantoina y amikacinano presentaron cambios significativos. Conclusiones: Los cambios en la...

The urinary tract infection (UTI) is the most common bacterial infection, caused by several germs like gramnegative bacillus ( E. Coli, P. Mirabilis, Klebsiella). This disease has a lot of non-resolved problems like resistance to the antibiotics and recurrence. The germ resistance is important at the moment to choose a first line antibiotic.The aim of the study was evaluate the evolution of E. Coli resistance to the frequent used antibiotics in female outpatients of our center with no complicate UTI in a 10 years period. We assessed retrospectively our database ofurine culture (UC) and antibiogram the years 1996 and 2005 from January to September using the Chi square test to compare the antibiotic sensitivity. In 1996 we found 242 patients with positive UC, the mean age was 46 years and E. Coli was responsible in 91,3 percent. In 2005 we had 296 patients with positive UC, the mean age was 52 years and E. Coli was responsible in 88,5 percent. We found a rise E. Coli resistance (statistically significant) to cotrimoxazol, sulbactam-ampicilin, pipemidic acid, cefotaxim and cefradin. Ciprofloxacin, norfloxacin, nitrofuranto in and amikacin present no significant changes. Gentamicin has an important increase of sensitivity.

Edema de la médula ósea de la rodilla / Bone marrow edema of knee

Bone marrow edema (BME) or transient bone marrow edema syndrome (TMES) affects the joints, particularly thehip and less frequently the knee and ankle. Knee problemsare usually related to traumatic causes, nevertheless, this can also be caused by micro traumatisms brought on bydaily life or overload. Diagnosis is confirmed by usingnuclear magnetic resonance (NMR), since both x-rays andcomputer assisted tomographies (CAT) are unsupportive,and scintigraph, though sensitive, is none specific. It isdescribed as the cause of pain in osteoarthritis and canalso be observed in transitory osteoporosis, in migratoryregional osteoporosis, and in the first stage of avascularbone necrosis (ABN), which is its main differential diagnosis. We present three cases of patients with knee pain, with no history of contusion. Two cases presented minor signs of osteoarthritis, two presented a decrease in bone density, and one presented hyperlaxity. NMRs were required, since normal procedures led to no results, and showed the existence of BME. Treatment was conservative, specially oriented towards unloading the joints, with a favorable evolution prior to six months.

Caracterización molecular de alelos ABO*O del locus de grupo sanguíneo ABO en tres poblaciones chilenas / Molecular Characterization of ABO*O Alleles at the ABO Group Locus in Three Chilean Populations

Background: Among the allelic variants of blood groups, the molecular characterization of ABO blood group has clinical and anthropological importance. Aim: To perform a characterization of the molecular variants of the allele ABO*O of the ABO blood group. Material and methods: Eighty four subjects of Aymara origin, living in Northern Chile, 75 individuals of Huilliche origin, living in Southern Chile and 82 subjects living in Santiago (Central Chile), were studied. All individuals were of group O, homozygotes for G261- deletion, that defines O1 alleles. Mutations G188A, G261-, G542A, T646A and C771T, described for alleles O1, O1variant and G542A were determined by PCR-RFLP (polymerase chain reaction-restriction fragment lenght polymorphism). Results: Allele O1variant has frequencies of 0.65, 0.81 and 0.6 in Aymara, Huilliche and Santiago subjects, respectively. The figures for allele O1 are 0.35, 0.19 and 0.4, respectively and those for the allele with G542A mutation are 0.119, 0.113 and 0.079, respectively. Conclusions: These results are concordant with the reported higher frequency of allele O1variant in South American aboriginal populations. The frequencies of G542A allele in these Chilean individuals are lower than those described for Amazon aborigines.

Caracterización genético molecular de habitantes de Caleta Paposo, último reducto Chango en Chile / Molecular and genetic characterization of Changos descendants living in Paposo Cove

Background: There are geographic and ethno historic evidences that relate Paposo cove, located 150 km south of the city of Antofagasta, with old fishermen-collector populations known as Changos, that lived in that zone in the XVII and XVIII centuries. Aim: To perform a genetic and molecular characterization of current Paposo inhabitants, through mitochondrial DNA polymorphism analysis and molecular analysis of classical ABO and Duffy blood groups. Material and methods: Forty unrelated individuals were studied. The presence of restriction polymorphisms that define A, B, C, and D Amerindian founder mitochondrial haplogroups was studied and molecular determination of classical blood groups were done by PCR. Results: One individual had A haplogroup (2.5 percent), 19 had B haplogroup (47.5 percent), six had C haplogroup (15 percent) and 11 had D haplogroup (27.5 percent). Three subjects (7.5 percent) did not have any of these haplogroups. Among ABO blood groups, the frequency of O101 allele was 0.39, that of allele O201 was 0.53 and that of A allele was 0.08. Duffy blood group frequencies were 0.58 for FY*A and 0.42 for FY*B. FY null allele was not found. Conclusions: The frequency distribution of Amerindian mitochondrial haplogroups in Paposo inhabitants suggest that these individuals are related with Aymara and Atacameño Amerindians that can be considered culturally and geographically close populations. This proposal is supported by the results of the molecular determination of classical blood groups. Our findings in Paposo cove may represent the distribution of these markers in Chango Indians, of whom there is limited physical evidence and that became extinct near 1890 (Rev Méd Chile 2004; 132: 663-72).

Distribución de alelos de los genes DRD4 y DAT1 del sistema dopaminérgico en la población mixta de Santiago de Chile / Distribution of alleles of DRD4 and DAT1 genes of the dopaminergic system in the mixed chilean population

Genes for dopamine receptor DRD4 and dopamine transporter DAT1 are highly polymorphic. Two alleles of these genes, namely the DRD4.7 and the DAT1*9 are frequently associated to the attention deficit disorder with hyperactivity. In Europe, the allele for DRD4 receptor with four repetitions (DRD4.4) has the highest frequency, with a median of 69 percent, followed by DRD4.7, with a frequency of 15 percent. South American indigenous populations have higher frequencies for DRD4.7 (61 percent) than for DRD4.4 (29 percent). The ten repetition allele for DAT1 transporter has a high frequency among Europeans (72 percent) and Amerindians (100 percent). The allele DAT1*9 is the second most frequent allele. Aim: To study the frequency of DRD4 and DAT1 alleles in a Chilean population sample. Material and methods: One hundred serum samples were obtained from blood donors in two public hospitals in Santiago. Polymorphic regions for DRD4 and DAT1 were amplified by polymerase chain reaction. Results: The allele DRD4.4 had a frequency of 59 percent and DRD4.7 a frequency of 27 percent. The allele DAT1*10 had a frequency of 74 percent, followed by DAT 1*9, with a frequency of 23 percent. Discussion: In a Chilean population sample, the frequency of DRD4 and DAT1 alleles was very similar to that of European populations

Composición genética de la población chilena: distribución de polimorfismos de DNA mitocondrial en grupos originarios y en la población mixta de Santiago / Genetic composition of the chilean population: analysis of mitochondrial DNA polymorphisms

Background: The analysis of mitochondrial DNA restriction site polymorphisms assigns most Latin American aborigines to four haplogroups. These are characterized by determined polymorphic restriction sites and a deletion of 9 base pairs in the intergenic region V. Aim: To study the distribution of mitochondrial DNA haplogroups in Chilean aboriginal groups, as well as in the mixed population of Santiago. Material and methods: One hundred twenty Aymara subjects and 23 Atacame-o subjects from the Northern part of Chile and 162 randomly chosen subjects residing in Santiago were studied. DNA was extracted from peripheral lymphocytes. Mitochondrial DNA was amplified by means of polymerase chain reaction. Results: The frequency of haplogroup B decreases from north to south. Aymaras in the north have the highest frequency (64 percent) and it is absent among the Yamanas (previously studied) in the extreme South. Haplogroups C and D show an inverse tendency. It is noteworthy that 84 percent of mitochondrial haplogroups of the mixed population of Santiago are of Amerindian origin whereas the Y-chromosomes are mainly European. Conclusions: The peculiar distribution of haplotypes indicate that the population of Santiago is the result of an asymmetric mating system in which the females ancestors were mainly Amerindian and the male ancestors mainly European

Infección con el virus de la hepatitis E en Chile: comunicación preliminar / Hepatitis E virus infection in Chile: preliminary report

Using and Elisa technique, IgG antibodies against hepatitis E virus were measured in 40 alcoholics, 40 hemophilics, 174 blood donors, 36 subjects with acute non A non B non C hepatitis and 66 subjects with acute hepatitis A. Antibodies were detected in 1 alcoholic (2,5 percent), 3 hemophilics (7,5 percent), 7 blood donors (4 percent), 3 patients with non-A-non-B-non-C hepatitis (8,3 percent) and 3 patients with acute hepatitis A (4,5 percent). A low frequency of hepatitis E infection was detected in the studied subjects