Dermatophytes are the leading cause of cutaneous fungal infection worldwide, followed by non-dermatophyte molds and Candida spp. Microbiological diagnosis is essential to identify the etiological agent and to guide targeted therapy. Conventional methods, including direct microscopy and fungal culture, are fundamental tools in the diagnostic workflow. This study aimed to assess quantitative Multiplex Tandem PCR performance in comparison with microscopy and culture for rapid and accurate identification in real clinical practice. A total of 50 clinical specimens were collected and analyzed with conventional methods. Direct microscopic examination yielded positive results in 45 out of 50 samples (90%), while fungal culture identified clinically significant fungi in 29 out of 50 cases (58%). The same 50 specimens were retrospectively analyzed using Multiplex MT-PCR, which detects major dermatophytes, Scopulariopsis, Aspergillus and Candida species. MT-PCR identified fungal DNA in 84% of samples. Compared to standard reference methods, the assay demonstrated a sensitivity of 84% and a specificity of 60%. Notably, MT-PCR identified fungal pathogens that were missed by conventional techniques in 32% of cases, significantly reducing the turnaround time. Conversely, 6% of samples were PCR-negative but culture-positive, likely reflecting pre-analytical variability and sample heterogeneity. Although the sample size was limited, MT-PCR proved to be a rapid and highly sensitive complementary diagnostic tool, warranting further investigation in larger-scale studies.
BACKGROUND:Epstein-Barr virus (EBV) and cytomegalovirus (CMV) are common opportunistic viruses in inflammatory bowel disease (IBD). Clinical features and risk factors of EBV and CMV infection in IBD patients have been explored. METHODS:Clinical information of IBD patients was collected. Viral loads were detected by quantitative polymerase chain reaction (qPCR) and Clostridioides difficile (C. difficile) toxin genes were detected using GeneXpert. Univariate and multivariate logistic regression analyses were performed. RESULTS:Both positive groups showed higher ulcerative colitis (UC) to Crohn's disease (CD) ratio and more severe disease activity (P < 0.05). The EBV infection group had higher proportions of males, older patients, severe diarrhea, and C. difficile infection (P < 0.05). Glucocorticoid therapy was associated with increased EBV and CMV prevalence and infliximab (IFX)/lizumab was associated with increased EBV prevalence (P < 0.05). Age > 60 years, UC, severe disease activity and IFX/lizumab use were identified as risk factors for EBV infection. UC was an independent risk factor for CMV infection. CONCLUSION:UC patients are more susceptible to CMV and EBV infection. Higher-risk patients for EBV infection include those aged >60 years, those with severe disease activity, or those on IFX/lizumab therapy, especially males and those with C. difficile infection.
Nontuberculous mycobacterial pulmonary disease in low-risk patients is rare and typically indolent. We report a case of Mycobacterium abscessus complex (MABC) pulmonary disease in a 71-year-old immunocompetent Italian man who presented with mild dyspnoea that markedly worsened following SARS-CoV-2 infection three months before admission. High-resolution CT showed diffuse small, irregular, predominantly consolidative opacities with peripheral bronchial thickening. Extensive investigations for tuberculosis, fungal infection, other pathogens, and malignancy were negative. Respiratory cultures subsequently yielded MABC, and molecular testing identified a functional erm(41) gene conferring inducible macrolide resistance, consistent with M. abscessus subsp. abscessus. Guideline-based multidrug therapy with intravenous amikacin, tedizolid, clofazimine, and moxifloxacin was initiated. Nephrotoxicity required substitution of intravenous amikacin with an inhaled formulation, followed by ototoxicity and further modification with tigecycline. Despite these adjustments, cultures remained persistently positive. Severe gastrointestinal intolerance and progressive weight loss ultimately led to treatment discontinuation and home oxygen therapy. One year after diagnosis, imaging revealed new cavitary lesions with advanced bilateral disease. The patient died from respiratory failure and severe cachexia. This case shows that MABC infection may follow an aggressive, life-threatening course even in immunocompetent individuals. Antimicrobial resistance combined with treatment-limiting toxicity underscores the urgent need for more effective, better-tolerated therapies and early multidisciplinary management.
The objective of this study was to investigate whether Candida albicans infection may contribute to the development of the carious process. This study included six adult patients, three with oral C. albicans infection and three healthy subjects (Candida-negative). All participants exhibited moderate dental caries intensity, determined by the result based on DMFT index. Simultaneously, the activity of dental caries did not differ between the subjects. In addition, the accumulation of dental plaque assessed using the Plaque Index (Pl.I) was moderate in all individuals. Salivary glucose and pH values did not differ between the subjects. The results suggest that the influence of chronic Candida infection on the development of dental caries is uncertain.
Mutations in the pncA gene of Mycobacterium tuberculosis, which encodes the PZase enzyme, are closely linked to pyrazinamide (PZA) resistance. Two clinical isolates, R1 and R2, which are resistant to pyrazinamide at concentrations of 100 μg/mL and 150 μg/mL, respectively, harbor multiple pncA mutations. The pncA R1 gene carries T41C, G419A, and A535G, causing Cys14Arg, Arg140His, and Ser179Gly substitutions in PZase; the pncA R2 gene has G76T, G112C, A403C, and G419A, resulting in Ala26Ser, Ala38Pro, Thr135Pro, and Arg140His changes. The relationship between the biochemical characteristics of the enzymes with pyrazinamide resistance in isolates R1 and R2 remains unclear. This paper presents the catalytic kinetics of mutant enzymes and explores their association with PZA resistance. The impact of these mutations on enzyme function was evaluated by expressing recombinant PZase in Escherichia coli, resulting in the production of proteins approximately 21 kDa in size, as confirmed by SDS-PAGE analysis. Kinetic analysis revealed reduced catalytic efficiency (kcat/KM) for the PZase-R1 and PZase-R2 variants, measured at 1.759 mM¯¹·min¯¹ and 1.500 mM¯¹·min¯¹, respectively, in comparison to the wild-type enzyme, which exhibited a value of 2.443 mM¯¹·min¯¹. These reductions correspond to decreases of 28.0% for PZase-R1 and 38.6% for PZase-R2. The observed declines in catalytic efficiency are likely to contribute to the development of resistance to pyrazinamide (PZA). Further studies, including site-directed mutagenesis and structural modelling, are needed to clarify the impact of each mutation on PZase function and drug interaction.
