A Difficult Differential Diagnosis in New Neck Masses: Retropharyngeal Abscess or Malignancy?

Retropharyngeal abscesses (RPAs) are rare in the adult population and rarer without an inciting event or comorbidity such as recent oral surgery, neck infection, or pharyngeal trauma. The definitive treatment is incision and drainage of the abscess. Clinical researchers have recently questioned whether invasive surgical intervention is necessary and posed the question of what role antibiotics play in management. Sequelae of RPAs are severe and include rupture of the abscess, erosion of the carotid artery, thrombophlebitis, and most seriously, airway compromise. We present a case where an atypical presentation of an RPA caused a disagreement among specialists, and the debate of whether the described case represented an abscess or malignancy caused a delay in diagnosis and treatment for the patient. Only after invasive and emergent surgical intervention was a final diagnosis able to be made. This case demonstrates the need for more research and official guidance on the management of new neck masses to hasten diagnosis and prevent devastating outcomes.

Epidemiological investigation of feline chronic gingivostomatitis and its relationship with oral microbiota in Xi'an, China.

Feline chronic gingivostomatitis (FCGS) is an ulcerative and/or proliferative disease that typically affects the palatoglossal folds. Because of its unknown pathogenesis and long disease course, it is difficult to treat and has a high recurrence rate. Most of the bacteria in the oral microbiota exist in the mouth symbiotically and maintain a dynamic balance, and when the balance is disrupted, they may cause disease. Disturbance of the oral microbiota may play an important role in the development of FCGS. In this study, the medical records of 3109 cats in three general pet hospitals in Xi 'an were collected. Sixty-one cats with FCGS were investigated via questionnaires, routine oral examinations and laboratory examinations. Oral microbiota samples were collected from 16 FCGS-affected cats, and microbial species were identified by 16S rDNA sequencing. The results showed that the incidence of FCGS had no significant correlation with age, sex or breed. However, the incidence of FCGS was associated with immunization, a history of homelessness and multicat rearing environments. The number of neutrophils and the serum amyloid A concentration were increased, and the percentage of cells positive for calicivirus antigen was high in all cases. All the cats had different degrees of dental calculus, and there were problems such as loss of alveolar bone or tooth resorption. Compared with those in healthy cats, the bacterial diversity and the abundance of anaerobic bacteria were significantly increased in cats with FCGS. Porphyromonas, Treponemas and Fusobacterium were abundant in the mouths of the affected cats and may be potential pathogens of FCGS. After tooth extraction, a shift could be seen in the composition of the oral microbiota in cats with FCGS. An isolated bacteria obtained from the mouths of the affected cats was homologous to P. gulae. Both the identified oral microbiota and the isolated strain of the cats with FCGS had high sensitivity to enrofloxacin and low sensitivity to metronidazole. This study provides support to current clinical criteria in diagnosing FCGS and proposes a more suitable antibiotic therapy.

Rapid Drug Susceptibility Testing to Preserve Antibiotics.

Antibiotic resistance is a global challenge likely to cost trillions of dollars in excess costs in the health system and more importantly, millions of lives every year. A major driver of resistance is the absence of susceptibility testing at the time a healthcare worker needs to prescribe an antimicrobial. The effect is that many prescriptions are unintentionally wasted and expose mutable organisms to antibiotics increasing the risk of resistance emerging. Often simplistic solutions are applied to this growing issue, such as a naïve drive to increase the speed of drug susceptibility testing. This puts a spotlight on a technological solution and there is a multiplicity of such candidate DST tests in development. Yet, if we do not define the necessary information and the speed at which it needs to be available in the clinical decision-making progress as well as the necessary integration into clinical pathways, then little progress will be made. In this chapter, we place the technological challenge in a clinical and systems context. Further, we will review the landscape of some promising technologies that are emerging and attempt to place them in the clinic where they will have to succeed.

High-throughput nanopore targeted sequencing for efficient drug resistance assay of Mycobacterium tuberculosis.

Drug-resistant tuberculosis (TB), especially multidrug-resistant tuberculosis (MDR-TB) and extensively drug-resistant tuberculosis (XDR-TB), is one of the urgent clinical problems and public health challenges. Culture-based phenotypic drug susceptibility testing (pDST) is time-consuming, and PCR-based assays are limited to hotspot mutations. In this study, we developed and validated a convenient and efficient approach based on high-throughput nanopore sequencing technology combined with multiplex PCR, namely nanopore targeted sequencing (NTS), to simultaneously sequence 18 genes associated with antibiotic resistance in Mycobacterium tuberculosis (MTB). The analytical performance of NTS was evaluated, and 99 clinical samples were collected to assess its clinical performance. The NTS results showed that MTB and its drug resistance were successfully identified in approximately 7.5 h. Furthermore, compared to the pDST and Xpert MTB/RIF assays, NTS provided much more drug resistance information, covering 14 anti-TB drugs, and it identified 20 clinical cases of drug-resistant MTB. The mutations underlying these drug-resistant cases were all verified using Sanger sequencing. Our approach for this TB drug resistance assay offers several advantages, including being culture-free, efficient, high-throughput, and highly accurate, which would be very helpful for clinical patient management and TB infection control.

Deep Amplicon Sequencing Reveals Culture Selection of Mycobacterium Tuberculosis by Clinical Samples.

The commonly-used drug susceptibility testing (DST) relies on bacterial culture and faces shortcomings such as long turnaround time and clone/subclone selection. We developed a targeted deep amplification sequencing (DAS) method directly applied to clinical specimens. In this DAS panel, we examined 941 drug-resistant mutations associated with 20 anti-tuberculosis drugs with an initial amount of 4 pg DNA and reduced clinical testing time from 20 days to two days. A prospective study was conducted using 115 clinical specimens mainly with Xpert® Mycobacterium tuberculosis/rifampicin (Xpert MTB/RIF) assay positive to evaluate drug-resistant mutation detection. DAS was performed on culture-free specimens, while culture-dependent isolates were used for phenotypic DST, DAS, and whole-genome sequencing (WGS). For in silico molecular DST, our result based on DAS panel revealed the similar accuracy to three published reports based on WGS. For 82 isolates, application of DAS showed better sensitivity (93.03% vs. 92.16%), specificity (96.10% vs. 95.02%), and accuracy (91.33% vs. 90.62%) than Mykrobe software using WGS. Compared to culture-dependent WGS, culture-free DAS provides a full picture of sequence variation at population level, exhibiting in detail the gain-and-loss variants caused by bacterial culture. Our study performs a systematic verification of the advantages of DAS in clinical applications and comprehensively illustrates the discrepancy in Mycobacterium tuberculosis before and after culture.

Risk factors associated with multidrug-resistant tuberculosis in areas with a moderate tuberculosis burden.

BACKGROUND: The emergence of multidrug-resistant tuberculosis (MDR-TB) or rifampicin-resistant (RR) TB poses a significant challenge for TB control initiatives on a global scale. This study's aim was to estimate the incidence of MDR-/RR-TB and identify the risk factors associated with their incidence in four provinces in northern Iran. METHODS: Drug susceptibility testing was conducted using the proportion method on Lowenstein-Jensen media. The demographic and clinical data were collected from the Iranian TB registry. RESULTS: Among 1083 individuals diagnosed with TB, 27 (2.5%) were identified as having MDR-/RR-TB, while 73 cases (6.7%) were any drug resistant (ADR). The statistical analysis revealed a significant association between marital status and MDR-/RR-TB (p=0.003). In addition, significant associations were observed between ADR-TB and gender (p=0.035) and previous treatment for TB (p=0.02). CONCLUSIONS: Our findings provide important information on the drug resistance pattern of Mycobacterium tuberculosis strains, as well as risk factors in northern Iran. Given the identified risk factors, creative approaches to promote treatment adherence in TB patients, particularly divorced/widowed women and individuals with a previous history of TB treatment, are required.

QMAC-DST for Rapid Detection of Drug Resistance in Pulmonary Tuberculosis Patients: A Multicenter Pre-Post Comparative Study.

Background/Objectives: This study explores the impact of QMAC-DST, a rapid, fully automated phenotypic drug susceptibility test (pDST), on the treatment of tuberculosis (TB) patients. Methods: This pre-post comparative study, respectively, included pulmonary TB patients who began TB treatment between 1 December 2020 and 31 October 2021 (pre-period; pDST using the Löwenstein-Jensen (LJ) DST (M-kit DST)) and between 1 November 2021 and 30 September 2022 (post-period; pDST using the QMAC-DST) in five university-affiliated tertiary care hospitals in South Korea. We compared the turnaround times (TATs) of pDSTs and the time to appropriate treatment for patients whose anti-TB drugs were changed based on these tests between the groups. All patients were permitted to use molecular DSTs (mDSTs). Results: A total of 182 patients (135 in the M-kit DST group and 47 in the QMAC-DST group) were included. The median TAT was 36 days for M-kit DST (interquartile range (IQR), 30-39) and 12 days for QMAC-DST (IQR, 9-15), with the latter being significantly shorter (p < 0.001). Of the total patients, 10 (5.5%) changed their anti-TB drugs based on the mDST or pDST results after initiating TB treatment (8 in the M-kit DST group and 2 in the QMAC-DST group). In the M-kit DST group, three (37.5%) patients changed anti-TB drugs based on the pDST results. In the QMAC-DST group, all changes were due to mDST results; therefore, calculating the time to appropriate treatment for patients whose anti-TB drugs were changed based on pDST results was not feasible. In the QMAC-DST group, 46.8% of patients underwent the first-line line probe assay compared to 100.0% in the M-kit DST group (p < 0.001), indicating that rapid QMAC-DST results provide quicker assurance of the ongoing treatment by confirming susceptibility to the current anti-TB drugs. Conclusions: QMAC-DST delivers pDST results more rapidly than LJ-DST, ensuring faster confirmation for the current treatment regimen.

The Putative Cytochrome b5 Domain-Containing Protein CaDap1 Homologue Is Involved in Antifungal Drug Tolerance, Cell Wall Chitin Maintenance, and Virulence in Candida albicans.

Candida albicans (Ca), a prominent opportunistic fungal pathogen in humans, has garnered considerable attention due to its infectious properties. Herein, we have identified and characterized CaCDAP1 (Ca orf19.1034), a homolog of ScDAP1 found in Saccharomyces cerevisiae. CaCDAP1 encodes a 183-amino acid protein with a conserved cytochrome b5-like heme-binding domain. The deletion of CaDAP1 renders Ca cells susceptible to caspofungin and terbinafine. CaDAP1 deletion confers resistance to Congo Red and Calcofluor White, and sensitivity to sodium dodecyl sulfate. The deletion of CaDAP1 results in a 50% reduction in chitin content within the cell wall, the downregulation of phosphorylation levels in CaMkc1, and the upregulation of phosphorylation levels in CaCek1. Notably, CaDAP1 deletion results in the abnormal hyphal development of Ca cells and diminishes virulence in a mouse systemic infection model. Thus, CaDAP1 emerges as a critical regulator governing cellular responses to antifungal drugs, the synthesis of cell wall chitin, and virulence in Ca.

Development of treatment strategies by comparing the minimum inhibitory concentrations and minimum fungicidal concentrations of azole drugs in dermatophytes.

We compared the minimum inhibitory concentrations (MICs) and minimum fungicidal concentrations (MFCs) of azoles in antifungal drug-susceptible, terbinafine-resistant, and lowly itraconazole (ITCZ)-susceptible strains of dermatophytes. To assess the MICs of ITCZ, ravuconazole (RVCZ), efinaconazole (EFCZ), and luliconazole (LUCZ) in the isolates, broth microdilution assays were performed based on the Clinical and Laboratory Standards Institute M38-A2 guidelines with modifications. After the assays for determining the MICs, the inoculum suspensions in wells were resuspended, then 10 µL of the growth solution in each well was inoculated onto potato dextrose agar with the use of a pipette. After 7 days of incubation at 28°C, the MFCs were determined as the lowest concentration of a drug that allowed the growth of colonies on the potato dextrose agar. The MICs in the dermatophytes were <0.03 to >32 mg/L for ITCZ, <0.03 to 4 mg/L for RVCZ, <0.03 to 2 mg/L for EFCZ, and <0.03 mg/L for LUCZ. The MFCs in the dermatophytes were 1 to >32 mg/L for ITCZ, 0.06 to >32 mg/L for RVCZ, <0.03 to 4 mg/L for EFCZ, and <0.03 to 2 mg/L for LUCZ. If the drug susceptibility test shows that the fungi are resistant to the drug, the treatment can be changed to a susceptible drug in advance, or if the fungi are low-susceptible, the treatment can be done with the recognition that it may require a longer treatment period than usual.

Construction of a Novel Mitochondria-Associated Gene Model for Assessing ESCC Immune Microenvironment and Predicting Survival.

Esophageal squamous cell carcinoma (ESCC) is among the most common malignant tumors of the digestive tract, with the sixth highest fatality rate worldwide. The ESCC-related dataset, GSE20347, was downloaded from the Gene Expression Omnibus (GEO) database, and weighted gene co-expression network analysis was performed to identify genes that are highly correlated with ESCC. A total of 91 transcriptome expression profiles and their corresponding clinical information were obtained from The Cancer Genome Atlas database. A mitochondria-associated risk (MAR) model was constructed using the least absolute shrinkage and selection operator Cox regression analysis and validated using GSE161533. The tumor microenvironment and drug sensitivity were explored using the MAR model. Finally, in vitro experiments were performed to analyze the effects of hub genes on the proliferation and invasion abilities of ESCC cells. To confirm the predictive ability of the MAR model, we constructed a prognostic model and assessed its predictive accuracy. The MAR model revealed substantial differences in immune infiltration and tumor microenvironment characteristics between high- and low-risk populations and a substantial correlation between the risk scores and some common immunological checkpoints. AZD1332 and AZD7762 were more effective for patients in the low-risk group, whereas Entinostat, Nilotinib, Ruxolutinib, and Wnt.c59 were more effective for patients in the high-risk group. Knockdown of TYMS significantly inhibited the proliferation and invasive ability of ESCC cells in vitro. Overall, our MAR model provides stable and reliable results and may be used as a prognostic biomarker for personalized treatment of patients with ESCC.

Clinical characteristics and antimicrobial susceptibility profiles of Mycobacterium abscessus and Mycobacterium massiliense pulmonary infection.

OBJECTIVES: Mycobacterium abscessus complex (MABC) is the most common rapidly growing Mycobacterium species in structural pulmonary diseases and can be life-threatening. This study aimed to assess the clinical characteristics and drug-susceptibility statuses of different M. abscessus (MAB) subspecies in the Zhejiang Province. METHODS: DNA sequencing was used to differentiate clinical MABC subspecies isolates. The Clinical and Laboratory Standards Institute guidelines were used to determine in vitro susceptibility of imipenem-relebactam (IMP-REL), omadacycline, and other conventional antibiotics. Patient clinical characteristics were collected and analysed. RESULTS: In total, 139 M. abscessus, 39 Mycobacterium massiliense, and 1 Mycobacterium bolletii isolates were collected, accounting for 77.7%, 21.8%, and 0.5% of the MABC isolates, respectively. Patients with M. abscessus pulmonary disease (M.ab-PD) had higher proportions of older adults, tuberculosis history, chronic pulmonary disease, and malignancy than those with M. massiliense pulmonary disease (M.ma-PD). Patients with M.ab-PD had higher rates of bilateral middle- and lower-lobe involvement than patients with M.ma-PD. Both subspecies showed high resistance rates to doxycycline and moxifloxacin, and clarithromycin-induced resistance was more common in M.ab than in M.ma. IMP-REL resulted in a twofold reduction in the minimum inhibitory concentration (MIC) value compared with imipenem alone among MAB; furthermore, the MIC was lower in M.ab than in M.ma. Omadacycline and tigecycline had comparable in vitro susceptibility, and the MIC showed no statistically significant difference between M.ab and M.ma. CONCLUSIONS: M.ab is the most prevalent MABC subspecies in the Zhejiang Province. Patients with M.ab-PD have complex underlying diseases and broader lobar lesions. IMP-REL and omadacycline are promising antibiotics for MABC infection treatment.

Influenza C virus susceptibility to antivirals with different mechanisms of action.

Antiviral susceptibility of influenza viruses was assessed using a high-content imaging-based neutralization test. Cap-dependent endonuclease inhibitors, baloxavir and AV5116, were superior to AV5115 against type A viruses, and AV5116 was most effective against PA mutants tested. However, these three inhibitors displayed comparable activity (EC50 8-22 nM) against type C viruses from six lineages. Banana lectin and a monoclonal antibody, YA3, targeting the hemagglutinin-esterase protein effectively neutralized some, but not all, type C viruses.

Clinical Distribution and Drug Susceptibility Characterization of Invasive Candida Isolates in a Tertiary Hospital of Xinjiang Province.

Objective: This study aims to investigate the clinical distribution characteristics and drug susceptibility profiles of invasive Candida isolates in a tertiary hospital in Urumqi. Methods: The examination was conducted on samples obtained from patients who were clinically diagnosed with invasive candidiasis in this hospital. A total of 109 strains of Candida strains were identified through the use of internal transcribed spacer (ITS) sequencing and fungal cultivation methods.The clinical distribution of the strains was analyzed. Antifungal drug susceptibility tests were performed using the Sensititre YO10 fungal drug susceptibility plate based on the micro-broth dilution method. Results: Candida albicans had the highest percentage (51.38%) among 109 Candida isolates, followed by C. glabrata (18.35%) and C. tropicalis (15.60%). The isolates were predominantly found in the respiratory department (41.28%), intensive care unit (ICU) (31.19%), and infection department (9.17%).The results of drug susceptibility tests indicated that amphotericin B, 5-fluorocytosine, and echinocandins exhibited good in vitro antifungal activity, with a susceptibility rate of over 96%. However, the azoles demonstrated low antifungal activity, especially posaconazole and voriconazole, which had high resistance rates of 64.71% for C. tropicalis and 70% for C. glabrata, respectively. Conclusion: In our hospital, Candida albicans was identified as the primary causal agent of invasive candidiasis. In terms of in vitro antifungal activity, echinocandins, amphotericin B, and 5-fluorocytosine demonstrated efficacy against invasive Candida infections. However, it was important to note that C. glabrata and C. tropicalis exhibited low susceptibility to azoles.

GenoMycAnalyzer: a web-based tool for species and drug resistance prediction for Mycobacterium genomes.

BACKGROUND: Drug-resistant tuberculosis (TB) is a major threat to global public health. Whole-genome sequencing (WGS) is a useful tool for species identification and drug resistance prediction, and many clinical laboratories are transitioning to WGS as a routine diagnostic tool. However, user-friendly and high-confidence automated bioinformatics tools are needed to rapidly identify M. tuberculosis complex (MTBC) and non-tuberculous mycobacteria (NTM), detect drug resistance, and further guide treatment options. RESULTS: We developed GenoMycAnalyzer, a web-based software that integrates functions for identifying MTBC and NTM species, lineage and spoligotype prediction, variant calling, annotation, drug-resistance determination, and data visualization. The accuracy of GenoMycAnalyzer for genotypic drug susceptibility testing (gDST) was evaluated using 5,473 MTBC isolates that underwent phenotypic DST (pDST). The GenoMycAnalyzer database was built to predict the gDST for 15 antituberculosis drugs using the World Health Organization mutational catalogue. Compared to pDST, the sensitivity of drug susceptibilities by the GenoMycAnalyzer for first-line drugs ranged from 95.9% for rifampicin (95% CI 94.8-96.7%) to 79.6% for pyrazinamide (95% CI 76.9-82.2%), whereas those for second-line drugs ranged from 98.2% for levofloxacin (95% CI 90.1-100.0%) to 74.9% for capreomycin (95% CI 69.3-80.0%). Notably, the integration of large deletions of the four resistance-conferring genes increased gDST sensitivity. The specificity of drug susceptibilities by the GenoMycAnalyzer ranged from 98.7% for amikacin (95% CI 97.8-99.3%) to 79.5% for ethionamide (95% CI 76.4-82.3%). The incorporated Kraken2 software identified 1,284 mycobacterial species with an accuracy of 98.8%. GenoMycAnalyzer also perfectly predicted lineages for 1,935 MTBC and spoligotypes for 54 MTBC. CONCLUSIONS: GenoMycAnalyzer offers both web-based and graphical user interfaces, which can help biologists with limited access to high-performance computing systems or limited bioinformatics skills. By streamlining the interpretation of WGS data, the GenoMycAnalyzer has the potential to significantly impact TB management and contribute to global efforts to combat this infectious disease. GenoMycAnalyzer is available at http://www.mycochase.org .

Bedaquiline susceptibility testing of Mycobacterium abscessus complex and Mycobacterium avium complex: A meta-analysis study.

OBJECTIVE: This study aims to estimate the overall in vitro activity of bedaquiline (BDQ) against clinical isolates of Mycobacterium abscessus complex (MABS) and M. avium complex (MAC), considering BDQ as a repurposed drug for non-tuberculous mycobacteria (NTM) infections. METHODS: We conducted a systematic review of publications in PubMed/ MEDLINE, Web of Science, and Embase up to 15 April 2023. Studies were included if they followed the Clinical and Laboratory Standards Institute (CLSI) criteria for drug susceptibility testing (DST). Using a random effects model, we assessed the overall in vitro BDQ resistance rate in clinical isolates of MABS and MAC. Sources of heterogeneity were analysed using Cochran's Q and the I2 statistic. All analyses were performed using CMA V3.0. RESULTS: A total of 24 publications (19 reports for MABS and 11 for MAC) were included. Using 1 µg/mL and 2 µg/mL as the breakpoint for BDQ resistance, the pooled rates of in vitro BDQ resistance in clinical isolates of MABS were found to be 1.8% (95% confidence interval [CI], 0.7-4.6%) and 1.7% (95% CI, 0.6-4.4%), respectively. In the case of MAC, the pooled rates were 1.7% (95% CI, 0.4-6.9%) and 1.6% (95% CI, 0.4-6.8%) for 1 µg/mL and 2 µg/mL, respectively. CONCLUSION: This study reports the prevalence of BDQ resistance in clinical isolates of MABS and MAC. The findings suggest that BDQ holds potential as a repurposed drug for treating MABS and MAC infections.

Genetic diversity of Mycobacterium tuberculosis strains isolated from spiritual holy water site attendees in Northwest Ethiopia. A cross-sectional study.

Background: The genetic diversity of Mycobacterium tuberculosis complex (MTBC) strains was characterized among isolates from individuals with pulmonary tuberculosis (PTB) symptoms attended holy water sites (HWSs) in the Amhara region, Ethiopia. Methods: A cross-sectional study was done from June 2019 to March 2020 to describe the genetic diversity and drug-resistance profiles of MTBC isolates. Sputum specimens were collected and cultured in the Löwenstein-Jensen culture medium. Line Probe Assay, MTBDRplus VER 2.0, and MTBDRsl VER 2.0 were used to detect first-and second-line anti-TB drug-resistance patterns. A spoligotyping technique was utilized to characterize the genetic diversity. Statistical analysis was performed using STATA 15. Results: Of 560 PTB-symptomatic participants, 122 (21.8%) were culture-positive cases. Spoligotyping of 116 isolates revealed diverse MTBC sublineages, with four major lineages: Euro-American (EA) (Lineage 4), East-African-Indian (EAI) (Lineage 3), Ethiopian (ETH) (Lineage 7), East Asian (EA) (Lineage 2). The majority (96.6%) of the isolates were EA (lineage 4) and EAI, with proportions of 54.3% and 42.2%, respectively. A total of 31 spoligotype patterns were identified, 26 of which were documented in the SITVIT2 database. Of these, there were 15 unique spoligotypes, while eleven were grouped with 2-17 isolates. SIT149/T3-ETH (n = 17), SIT26/CAS1-DELHI (n = 16), SIT25/CAS1-DELHI (n = 12), and SIT52/T2 (n = 11) spoligotypes were predominant. A rare spoligotype pattern: SIT41/Turkey and SIT1/Beijing, has also been identified in North Shewa. The overall clustering rate of sub-lineages with known SIT was 76.4%.Of the 122 culture-positive isolates tested, 16.4% were resistant to rifampicin (RIF) and/or isoniazid (INH). Multidrug-resistant TB (MDR-TB) was detected in 12.3% of isolates, five of which were fluoroquinolones (FLQs) resistant. SIT149/T3-ETH and SIT21/CAS1-KILI sublineages showed a higher proportion of drug resistance. Conclusions: Diverse MTBC spoligotypes were identified, with the T and CAS families and EA (lineage 4) predominating. A high prevalence of drug-resistant TB, with SIT149/T3-ETH and CAS1-KILI sublineages comprising a greater share, was observed. A study with large sample size and a sequencing method with stronger discriminatory power is warranted to understand better the genetic diversity of circulating MTBC in this cohort of study, which would help to adopt targeted interventions.

Clinical characteristics and drug resistance of Nocardia in Henan, China, 2017-2023.

BACKGROUND: The aim of this study was to investigate the clinical features of Nocardia infections, antibiotic resistance profile, choice of antibiotics and treatment outcome, among others. In addition, the study compared the clinical and microbiological characteristics of nocardiosis in bronchiectasis patients and non-bronchiectasis patients. METHODS: Detailed clinical data were collected from the medical records of 71 non-duplicate nocardiosis patients from 2017 to 2023 at a tertiary hospital in Zhengzhou, China. Nocardia isolates were identified to the species level using MALDI-TOF MS and 16S rRNA PCR sequencing. Clinical data were collected from medical records, and drug susceptibility was determined using the broth microdilution method. RESULTS: Of the 71 cases of nocardiosis, 70 (98.6%) were diagnosed as pulmonary infections with common underlying diseases including bronchiectasis, tuberculosis, diabetes mellitus and chronic obstructive pulmonary disease (COPD). Thirteen different strains were found in 71 isolates, the most common of which were N. farcinica (26.8%) and N. cyriacigeorgica (18.3%). All Nocardia strains were 100% susceptible to both TMP-SMX and linezolid, and different Nocardia species showed different patterns of drug susceptibility in vitro. Pulmonary nocardiosis is prone to comorbidities such as bronchiectasis, diabetes mellitus, COPD, etc., and Nocardia is also frequently accompanied by co-infection of the body with pathogens such as Mycobacterium and Aspergillus spp. Sixty-one patients underwent a detailed treatment regimen, of whom 32 (52.5%) received single or multi-drug therapy based on TMP-SMX. Bronchiectasis was associated with a higher frequency of Nocardia infections, and there were significant differences between the bronchiectasis and non-bronchiectasis groups in terms of age distribution, clinical characteristics, identification of Nocardia species, and antibiotic susceptibility (P < 0.05). CONCLUSIONS: Our study contributes to the understanding of the species diversity of Nocardia isolates in Henan, China, and the clinical characteristics of patients with pulmonary nocardiosis infections. Clinical and microbiologic differences between patients with and without bronchiectasis. These findings will contribute to the early diagnosis and treatment of patients.

The prevalence, clinical reasoning and impact of non-standard anti-tuberculosis regimens at the initial prescription.

Regarding clinically-concerning non-standard initial anti-tuberculous (TB) regimens, few studies have examined their prevalence, risk factors and impacts. We recruited patients with drug susceptible TB and non-standard initial anti-TB regimens (NSTB group) and matched them with patients with standard initial regimens (STB group) in a 1:1 ratio. The risk factors and outcomes were analyzed. During the 11-year study period, we analyzed 50 (3.7%) patients with NSTB from a total set of 1337 patients with drug-susceptible TB. Pyrazinamide (60%) was the drug most commonly not prescribed in the NSTB group, followed by ethambutol (34%). Multivariable logistic regression identified independent risk factors as underlying eye disease (adjusted odds ratio [aOR]: 8.869; 95% CI 2.542-30.949; p = 0.001), gout/hyperuricemia (aOR: 4.012 [1.196-13.425]; p = 0.024), and liver disease (aOR: 12.790 [3.981-41.089]; p < 0.001). The NSTB group had longer treatment durations (281 ± 121 vs. 223 ± 63 days; p = 0.003) and more occurrences of treatment interruption (26% vs. 8%; p = 0.021) than the STB group. In conclusion, NSTB occurs in around 3.7% of patients and is associated with longer treatment and more treatment interruption. The risk factors might include underlying liver and eye diseases, and gout. Further studies to improve non-standard initial regimens and prevent negative outcomes are warranted.

Long-term di-(2-ethylhexyl) phthalate exposure reduces sorafenib treatment efficacy by enhancing mesenchymal transition in hepatocellular carcinoma.

Di(2-ethylhexyl) phthalate (DEHP) is a worldwide common plasticizer. Nevertheless, DEHP is easily leached out to the environment due to the lack of covalent bonds with plastic. High dose of DEHP exposure is often observed in hemodialysis patients because of the continual usage of plastic medical devices. Although the liver is the major organ that catabolizes DEHP, the impact of long-term DEHP exposure on the sensitivity of liver cancer to chemotherapy remains unclear. In this study, we established long-term DEHP-exposed hepatocellular carcinoma (HCC) cells and two NOD/SCID mice models to investigate the effects and the underlying mechanisms of long-term DEHP exposure on chemosensitivity of HCC. The results showed long-term DEHP exposure potentially increased epithelial-mesenchymal transition (EMT) in HCC cells. Next generation sequencing showed that long-term DEHP exposure increased cell adhesion/migratory related genes expression and blunted sorafenib treatment induced genes alterations. Long-term exposure to DEHP reduced the sensitivity of HCC cells to sorafenib-induced anti-migratory effect by enhancing the EMT transcription factors (slug, twist, and ZEB1) and mesenchymal protein (vimentin) expression. In NOD/SCID mice model, we showed that long-term DEHP-exposed HCC cells exhibited higher growth rate. Regarding the anti-HCC effects of sorafenib, subcutaneous HuH7 tumor grew slowly in sorafenib-treated mice. Nonetheless, the anti-tumor growth effect of sorafenib was not observed in long-term DEHP-exposed mice. Higher mesenchymal markers and proliferating cell nuclear antigen (PCNA) expression were found in sorafenib-treated long-term DEHP-exposed mice. In conclusion, long-term DEHP exposure promoted migratory activity in HCC cells and decreased sorafenib sensitivity in tumor-bearing mice.