BACKGROUND:Ziehl-Neelsen (ZN) staining is routinely used for tuberculosis (TB) diagnosis, but cannot differentiate viable from nonviable bacilli. This limitation is particularly relevant in smear-positive pulmonary TB patients, where assessment of treatment response is essential. Fluorescein diacetate/ethidium bromide (FDA/EtBr) viability microscopy detects live Mycobacterium tuberculosis based on metabolic activity. This study compared the diagnostic performance of FDA/EtBr microscopy with ZN staining, using culture and drug susceptibility testing (DST) as the reference standard. METHODS:A cross-sectional study was conducted on 300 smear-positive pulmonary TB patients at Santosh Medical College, Ghaziabad, and National Institute of TB and Respiratory Diseases, New Delhi. After n-acetyl-l-cysteine-sodium hydroxide decontamination, sputum samples were examined using ZN staining, FDA/EtBr viability microscopy, and mycobacteria growth indicator tube 960 culture/DST. Sensitivity, specificity, positive predictive value, negative predictive value (NPV), and diagnostic accuracy were calculated, and paired statistical comparision were performed and statistical significance ( P < 0.05) was assessed for diagnostic outcomes. Inter-test agreement was evaluated using Cohen's κ-statistic. RESULTS:FDA/EtBr microscopy demonstrated significantly higher sensitivity (94.4% vs. 88.9%; absolute increase 5.5%, P = 0.018) and higher diagnostic accuracy (91.0% vs. 86.7%; absolute increase 4.3%, P = 0.04) compared to ZN staining. While ZN staining showed marginally higher specificity (66.7% vs. 60.0%; P = 0.42), FDA/EtBr provided a significantly improved NPV (54.5% vs. 40.0%; absolute increase 14.5%, P = 0.03). Agreement with culture/DST was almost perfect for FDA/EtBr (κ = 0.85) and substantial for ZN staining (κ = 0.72). CONCLUSION:FDA/EtBr viability microscopy offers statistically significant improvements in sensitivity, NPV, and diagnostic accuracy over ZN staining in smear-positive pulmonary TB patients, supporting its prioritized use for treatment monitoring and programmatic decision-making in resource-limited, high-burden settings.
BACKGROUND:The coexistence of nontuberculous mycobacterial pulmonary disease (NTM-PD) and chronic obstructive pulmonary disease (COPD) represents a severe clinical phenotype. This study aimed to investigate the factors associated with COPD comorbidity in patients with NTM-PD and evaluate the discriminatory performance of novel composite inflammatory-nutritional indices, specifically the C-reactive protein-to-albumin ratio (CAR) and the neutrophil-to-lymphocyte ratio-to-albumin ratio (NAR). METHODS:In this single-center, retrospective, cross-sectional study, we reviewed the clinical records of 153 patients with NTM-PD diagnosed between January 2019 and December 2024. Eligible patients were categorized into the NTM-PD alone group and the NTM-PD with comorbid COPD group based on postbronchodilator pulmonary function testing. A clinically driven multivariable logistic regression model was used to identify factors associated with COPD comorbidity after adjustment for potential confounders, including smoking index, comorbidity score, and NTM species. Discriminatory performance was assessed using receiver operating characteristic analysis, with internal validation by 1000-resample bootstrapping. Model calibration was evaluated using the Brier score and calibration plot, and clinical utility was explored using decision curve analysis. RESULTS:Of the 153 included patients, 75 (49.0%) had NTM-PD alone, and 78 (51.0%) had comorbid COPD. In the multivariable model, male sex (odds ratio [OR] = 4.93, 95% confidence interval [CI]: 2.01-12.09, P < 0.001), the presence of computed tomography (CT) cavities (OR = 3.82, 95% CI: 1.57-9.30, P = 0.003), and a higher NAR level (per 0.1-unit increase, OR = 1.85, 95% CI: 1.16-2.93, P = 0.009) were independently associated with COPD comorbidity. CAR and NAR showed similar discriminatory performance, with area under the curves (AUCs) of 0.768 and 0.767, respectively. The multivariable model showed good discrimination after internal validation by 1000-resample bootstrapping (bootstrapped AUC = 0.858, 95% CI: 0.796-0.910) and acceptable calibration (Brier score = 0.164). CONCLUSIONS:Male sex, the presence of CT cavities, and elevated NAR were independently associated with COPD comorbidity in patients with NTM-PD. In addition, CAR and NAR showed acceptable discriminatory performance as potential adjunctive screening markers for identifying patients who may warrant further evaluation for concurrent COPD. However, external validation is still required before broader clinical application.
Paradoxical reaction (PR) in lymph node tuberculosis (LNTB) is characterized by the worsening of existing lesions or the appearance of new lesions after an initial favourable response to antitubercular therapy (ATT). Although frequently reported in HIV-infected individuals, it can also occur in immunocompetent patients and may be mistaken for treatment failure or disease relapse. We report a 25-year-old immunocompetent woman with microbiologically confirmed cervical LNTB who developed recurrent lymph node enlargement during ATT and again after completing treatment. The diagnosis was established by excisional lymph node biopsy demonstrating necrotizing granulomatous inflammation, acid-fast bacilli on Ziehl-Neelsen staining, and detection of Mycobacterium tuberculosis by GeneXpert without rifampicin resistance. Despite initial clinical improvement, she experienced multiple episodes of cervical lymphadenopathy. During these episodes, smear microscopy and GeneXpert remained positive, whereas mycobacterial cultures were repeatedly negative. Following careful microbiological reassessment, the enlargements were managed conservatively without extending or modifying ATT. The lesions resolved spontaneously, and no constitutional symptoms or evidence of viable bacilli were identified. This case highlights the diagnostic challenge of distinguishing paradoxical reactions from relapse or treatment failure in LNTB. Repeated negative cultures, absence of clinical deterioration, and spontaneous resolution without therapeutic escalation supported the diagnosis of PR. Recognition of this phenomenon is essential to avoid unnecessary investigations and prolonged treatment.
BACKGROUND:Tuberculosis (TB) remains a major public health challenge, with India bearing the largest global burden. Rapid molecular diagnostics such as GeneXpert Mycobacterium tuberculosis /rifampicin (MTB/RIF), Truenat MTB/MTB Plus, and first-line line probe assay (FL-LPA) have improved case detection and RIF resistance identification, but their comparative performance with conventional Ziehl-Neelsen (ZN) smear microscopy and mycobacteria growth indicator tube (MGIT) culture requires evaluation. METHODS:A 16-month retrospective observational study (January 2024-April 2025) at a tertiary care hospital in New Delhi analyzed 9468 clinical specimens. Theis was to compare the diagnostic performance of molecular methods such as GeneXpert MTB/RIF, Truenat MTB/MTB Plus, and FL-LPA with ZN smear microscopy and MGIT culture for pulmonary and extrapulmonary TB, and to assess RIF resistance detection. All samples underwent ZN smear, MGIT culture, and molecular testing. Nucleic acid amplification test (NAAT)- positive samples were subjected to FL-LPA for resistance profiling. RESULTS:Out of 9468 clinical specimens analyzed, MTB was detected in 989 (10.45%) cases. Positivity was slightly higher in pulmonary samples (11.4%) compared to extrapulmonary samples (9.5%). RIF resistance was identified in 61 (6.2%) cases, whereas 36 (3.64%) results were indeterminate, most of which occurred in specimens with very low bacillary load. ZN smear microscopy detected only 19.11% of NAAT-positive samples, and smear positivity increased significantly with increasing bacterial load ( P < 0.001). Among the 660 samples evaluated by both NAAT and MGIT culture, concordant positivity was observed in 30 cases, with overall agreement improving as bacillary load increased (overall agreement: 29.7%). FL-LPA detected RIF resistance in 9 of 44 samples tested and revealed discordance with NAAT results in several cases. CONCLUSION:GeneXpert MTB/RIF and Truenat MTB Plus outperform smear microscopy and MGIT in sensitivity, particularly for low-bacillary load. FL-LPA enhances resistance detection, identifying additional RIF-resistant cases missed by NAAT. Incorporating NAAT as the frontline diagnostic, complemented by LPA and culture, can strengthen TB detection and drug resistance surveillance in high-burden settings.
BACKGROUND:Tuberculosis (TB) remains a major global health challenge, responsible for substantial morbidity and mortality. Understanding national epidemiological patterns, particularly in countries with large expatriate populations, is essential to update and guide both local and international TB control strategies. This study describes the epidemiology of TB in Qatar over an 8-year period (2016-2023). METHODS:A retrospective cohort analysis using the Communicable Disease Center national TB registry. All individuals with confirmed Mycobacterium tuberculosis infection were included. Demographic characteristics, incidence, mortality, site of disease, and drug resistance patterns were included. Incidence rates were calculated using national population estimates and stratified by age, sex, nationality, and clinical form. RESULTS:A total of 6373 TB cases were reported during the study period. Annual incidence fluctuated between 20 and 37 per 100,000 population, consistently below both the global average and the World Health Organization End TB 2025 milestone target. A temporary spike was observed in 2021, possibly related to COVID-19 disruptions in health services and migration patterns. The majority of cases occurred in the 25-54 years age group. Males had consistently higher incidence rates than females. Non-Qataris accounted for the overwhelming majority of cases, particularly expatriates from high TB burden countries. The proportion of rifampicin-resistant or multidrug-resistant TB remained stable at 0.5%-1.8%, below the global average, with two cases of extensively drug-resistant TB identified. CONCLUSION:TB incidence in Qatar remains relatively low, with the burden falling disproportionately on working-age male expatriates from high-incidence countries. The findings highlight the importance of targeted screening, continuity of TB services during health system disruptions, and sustained surveillance of drug-resistant TB. These results provide insights relevant not only to Qatar but also to other low-incidence, high-migration countries striving to achieve global TB elimination goals.
Secondary hemophagocytic lymphohistiocytosis (HLH) is a life-threatening hyperinflammatory syndrome most commonly triggered by infection, malignancy, or transplant-related immune dysregulation. Rapidly growing mycobacteria are uncommon causes of disseminated infection and have only rarely been reported as infectious triggers of HLH. A 56-year-old immunocompromised woman with a history of allogeneic hematopoietic stem cell transplant presented with recurrent fever, progressive transaminitis, and laboratory features consistent with secondary HLH. Liver biopsy showed granulomatous hepatitis with iron overload. Initial treatment with dexamethasone and anakinra resulted in transient clinical improvement. Less than 2 weeks later, she was readmitted with worsening hepatic dysfunction and found to have acid-fast bacilli in blood and bone marrow cultures, later identified as Mycobacterium immunogenum. Despite targeted antimicrobial therapy, the patient developed progressive hepatic and renal failure and died. To our knowledge, this case represents the first reported case of disseminated M. immunogenum infection precipitating secondary HLH, expanding the recognized clinical spectrum of this rapidly growing nontuberculous mycobacterium and highlights the diagnostic challenges of atypical mycobacterial infection in immunocompromised hosts.
BACKGROUND:This study estimated the prevalence of depression among Indonesian multidrug-resistant tuberculosis (MDR-TB) patients and quality of life (QoL) between shorter and longer regimens, as well as factors associated with depression. METHODS:A cross-sectional study was conducted at Haji Hospital from May to November 2024, using the Indonesian Patient Health Questionnaire-9 (PHQ-9) and the WHOQOL BREF to assess depression and QoL. A cutoff ≥5 of the PHQ-9 score was classified as depression. We used an independent t -test to analyze the differences between the two groups and a bivariate test to analyze depression-related factors. RESULTS:Eighteen and 24 MDR-TB patients received shorter and longer regimens during the study period. The study found that the prevalence of depression was higher (55.1%) in patients receiving longer regimens than in shorter regimens (33.3%), with a P = 0.036. 16/24 of patients (55.2%) had mild-to-moderate depression in longer regimens. MDR-TB patients who had a history of TB treatment were 4.97 times more likely to develop depression. The mean score of each domain and the total score of WHOQOL BREF were similar between the two groups, with a P ≥ 0.05. CONCLUSION:In conclusion, approximately 50% of MDR-TB patients receiving longer regimens had depression, and a history of TB treatment is a risk factor for developing depression; therefore, TB treatment approaches should address psychological distress among MDR-TB patients.
The concurrent presentation of two distinct mycobacterial diseases - Mycobacterium tuberculosis and Mycobacterium leprae - in a single patient is exceptionally rare. Lepromatous leprosy (LL), the multibacillary form of Hansen's disease, is characterized by profound defects in cell-mediated immunity, which may predispose individuals to other intracellular infections, including tuberculosis. We present a unique case of a patient with undiagnosed lepromatous leprosy presenting with ichthyosiform scaling and autonomic dysfunction who developed a life-threatening pulmonary complication from reactivation pulmonary tuberculosis (PTB). A 54-year-old male farmer presented to the emergency department with acute respiratory distress due to a large right-sided spontaneous pneumothorax complicated by bilateral massive subcutaneous emphysema. He reported a chronic cough, weight loss, and night sweats over several months, with a history of treated PTB 15 years back. Systemic examination revealed diffuse, symmetrical ichthyosiform scaling of the skin, bilateral peripheral neuropathy in a stocking-glove distribution, palpably thickened ulnar nerves, and orthostatic hypotension suggestive of autonomic dysfunction. Skin slit smear demonstrated numerous acid-fast bacilli (Bacteriological Index 5+), and skin biopsy confirmed lepromatous leprosy with a diffuse histiocytic infiltrate. Sputum examination was positive for Mycobacterium tuberculosis . The patient was managed with intercostal chest drain insertion for the pneumothorax and concurrently initiated on anti-tubercular therapy (ATT) and World Health Organization multi-drug therapy (MDT) for multibacillary leprosy. The pneumothorax resolved completely by day 7, and sputum smear converted to negative by day 12. At a 2-month follow-up, the patient remained clinically stable with no leprosy reactions and improving respiratory symptoms. This case highlights the importance of considering underlying immunosuppressive conditions, such as lepromatous leprosy, in patients presenting with complicated tuberculosis. The ichthyosiform presentation of leprosy is often misdiagnosed, and autonomic dysfunction indicates advanced disease. This report highlights the delicate and often difficult battle between mycobacterial diseases and the human body's defences - a battle that has profound consequences for how we diagnose illness, care for patients, and protect the health of entire communities where these diseases are most common.
Testicular germ cell tumors (TGCTs) are the most common solid malignancies in young adult men. Advanced disease requiring systemic chemotherapy may lead to immunosuppression and increase vulnerability to opportunistic infections, particularly in tuberculosis (TB)-endemic regions. Coexistence of visceral metastases and infectious comorbidities such as pulmonary TB can substantially complicate diagnostic evaluation and therapeutic decision-making. Latent TB infection (LTBI) reactivation following chemotherapy is a recognized but likely underreported complication in patients with solid tumors, posing additional clinical challenges. A 41-year-old male with a history of mixed TGCT who had undergone radical orchiectomy followed by platinum-based chemotherapy, presented with chronic cough, weight loss, and neurological symptoms. Imaging revealed a large pulmonary mass and a cerebral lesion consistent with metastases. Further evaluation confirmed pulmonary and brain metastases of TGCT origin. Pulmonary TB was bacteriologically confirmed by bronchoalveolar lavage GeneXpert. He received anti-TB therapy, supportive neurological treatment, and delayed neurosurgery after stabilization. Temporal association between prior chemotherapy, significant immunosuppression, and active TB development raised the suspicion of LTBI reactivation. He was discharged in the stable condition with plans for oncologic restaging and second-line chemotherapy. This case highlights the diagnostic and therapeutic challenges posed by the coexistence of metastatic TGCT and pulmonary TB. In TB-endemic settings, clinicians should maintain a high index of suspicion for TB in immunocompromised cancer patients presenting with pulmonary lesions. Multidisciplinary management and careful timing of oncologic and anti-TB treatments are essential to optimize the outcomes, and possible reactivation of LTBI should be considered following chemotherapy.
BACKGROUND:Drug-resistant tuberculosis (TB), especially rifampicin-resistant and multidrug-resistant TB, remains a significant public health challenge worldwide. Rapid and accurate methods for molecular diagnostics, such as first-line line probe assay (FL-LPA), are recommended by the World Health Organization for early detection of Rif and isoniazid resistance. However, limited data are available comparing resistance patterns between extrapulmonary TB (EPTB) and pulmonary TB (PTB). This study aims to compare first-line anti-tubercular drug resistance patterns and molecular mutations associated with katG, rpoB, and inhA genes between PTB and EPTB. METHODS:This study was a prospective analysis of 471 Mycobacterium tuberculosis samples subjected to the FL-LPA or the genotype MTBDRplus for the detection of Rif, isoniazid, and multidrug resistance. Demographic, clinical, microbiological, and molecular resistance data were compared between PTB and EPTB isolates. Resistance-associated mutations in the rpoB , katG , and inhA genes were evaluated. RESULTS:PTB accounted for the majority of samples (94.1%), whereas EPTB constituted 5.9%. PTB patients were more likely to be male, while EPTB patients were more likely to be female. The majority of drug resistance, or 94.1% of all resistant patterns, was found in PTB samples. The most prevalent resistance profile, especially in PTB patients, was isoniazid mono-resistance (H), which was mostly linked to the katG S315T mutation and indicated high-level isoniazid resistance. Canonical rpoB mutations in the rifampicin (Rif) resistance-determining region, such as S531 L, D516V, and H526 replacements, were the main cause of Rif resistance. In line with their paucibacillary character, EPTB cases showed decreased bacillary burden, lower smear positivity, and a narrow range of resistance-associated mutations. Both PTB and EPTB isolates had InhA promoter alterations linked to low-level isoniazid resistance. CONCLUSION:The study demonstrates a substantially higher burden of molecular drug resistance in PTB than in EPTB. The predominance of canonical rpoB and katG mutations highlights ongoing transmission of drug-resistant strains, emphasizing the value of FL-LPA in the routine TB diagnosis. Globally, molecular drug susceptibility testing, including extrapulmonary specimens, remains essential to guide appropriate therapy and strengthen TB control efforts under national and global elimination programs.
BACKGROUND:The Mycobacterium tuberculosis complex (MTBC) includes human-and animal-adapted species. Routine TrueNat™ testing detects MTBC but does not differentiate subspecies. This study evaluated the reuse of residual TrueNat™ DNA eluates for MTBC subspecies identification. METHODS:A cross-sectional laboratory feasibility study was performed using residual DNA (~78 µL) from 1,115 high-bacillary-load TrueNat™ MTBC-positive clinical specimens collected between 2022 and 2025. A two-step real-time polymerase chain reaction (PCR) assay targeting IS1081, MTCHum, MTCAni, and species-specific loci for Mycobacterium bovis (Mbov), Mycobacterium caprae (Mcap), and Mycobacterium orygis (Morg) was performed. All Mbov detections underwent confirmatory PCR and culture. RESULTS:All eluates produced valid amplification. Of 1,115 samples, 1,114 (99.91%) were identified as M. tuberculosis sensu stricto and one (0.09%) as Mbov. The Mbov isolate, obtained from a 2-year-old child with lymphadenitis, was confirmed to be a Bacillus Calmette-Guérin (BCG) vaccine strain rather than wild-type Mbov. No Mcap or Morg were detected. Negative controls remained negative, and repeat testing showed 100% concordance. CONCLUSIONS:Residual DNA from routine TrueNat™ testing can be effectively reused for MTBC subspecies differentiation. This implementation feasibility study demonstrates that residual DNA from routine TrueNat™ testing can be reused for MTBC subspecies differentiation within existing workflows without additional specimen collection or DNA extraction. Dedicated validation and epidemiologic studies are required to evaluate its utility in surveillance applications.
BACKGROUND:Emerging fluoroquinolone (FQ) resistance threatens multidrug-resistant tuberculosis (MDR-TB) management, complicating access to shorter regimens. This study characterizes FQ-resistant TB (FQ-R-TB) patients in Surabaya, Indonesia, and assesses diagnostic performance and therapeutic outcomes associated with this resistance. METHODS:A retrospective cohort analysis was conducted using national TB data from 1037 MDR-TB patients (2020-2025). Among them, 32 cases with genotypic FQ resistance (Xpert MTB/XDR) were stratified into concordant (genotypic mutation with phenotypic resistance, n = 21) and discordant (genotypic mutation with phenotypic susceptibility, n = 11) groups. Demographics, comorbidities, diagnostics, and treatment outcomes were evaluated. RESULTS:The proportion of FQ resistance among MDR-TB patients rose from 0% in 2020 to 1.37% in 2025. Discordant cases were significantly older (mean: 54 ± 14; P = 0.203), predominantly male (10:1; P = 0.037), had higher body mass index (BMI; 24.44 ± 6.04; P = 0.197), and had a markedly higher prevalence of diabetes mellitus (90.9% versus 9.5%; P = 0.028). Diagnostic discordance occurred in 34.4% of FQ-R-TB cases, causing 1-3 month delays in regimen adjustment and initial ineffective FQ exposure. While subsequent FQ-free BPaL regimens improved outcomes, initial diagnostic uncertainty complicated decisions and increased adverse effects. CONCLUSION:FQ resistance is an emerging threat in Surabaya. Diagnostic discordance and high comorbidity burden complicate treatment. Advanced age and higher BMI are linked to increased diabetes probability. Diabetes is a powerful predictor of genotypic-phenotypic discordance, likely via host-mediated mechanisms affecting bacterial fitness and resistance expression. A strong clinical consensus is needed to recommend genotypic test results as the primary guide for treating TB patients with diabetes. However, for diabetic TB patients whose initial phenotypic results indicate FQ susceptibility, close monitoring of their clinical and microbiological response during therapy remains crucial to confirm effectiveness until more definitive evidence is available.
BACKGROUND:Multidrug-resistant tuberculosis (MDR-TB) is difficult to treat and has a high transmission risk and a poor prognosis, imposing a severe burden on patients and their families. The aim of this study is to explore the molecular biological characteristics of MDR Mycobacterium tuberculosis (MTB) in Urumqi through the analysis of gene mutations and the clustering patterns of MDR MTB strains. METHODS:This study focused on TB patients diagnosed and registered with culture-positive MTB who were over the age of 16 in Urumqi. The GenoType MTBDRplus assay and mycobacterial interspersed repetitive unit-variable number tandem repeat techniques were employed to analyze gene mutations and the genetic clustering of MDR-TB strains in Urumqi. RESULTS:Among the 319 MTB strains analyzed, the Beijing genotype was predominant, accounting for 49.53%. Of the MDR MTB strains, 14 were identified, with the Beijing genotype being the most prevalent (73.68%), and the prevalence of MDR MTB in Beijing strains was 8.86%. The clustering rate of MDR MTB in Urumqi was found to be 5.26%. In addition, a special genotype was observed. CONCLUSION:The molecular biological characteristics of MDR MTB in Urumqi exhibit distinct features. Therefore, modern molecular epidemiological techniques, such as molecular biology and deoxyribonucleic acid fingerprinting, are critical for improving diagnostic speed, enabling effective case tracking, and investigating the sources of transmission in the region.
BACKGROUND:Mycobacterium tuberculosis ( M.tb ) remains a leading global cause of mortality. The current Bacillus Calmette-Guérin vaccine lacks efficacy in adults and fails to generate a long-term memory response. With the rise of multidrug-resistant strains, there is an urgent need for novel vaccines that can provide broader protection. This study aimed to design a multiepitope vaccine (MEV) targeting hallmark proteins involved in different aspects of M.tb virulence. METHODS:Four unique M.tb proteins, Rv1507A (role in memory response), Rv1509 (role in phagolysosomal escape), Rv1954A (role in macrophage activation/antigen presentation), and Rv2231A (role in persistence) were selected. In silico analyses were performed to identify epitopes with high-binding affinity for Toll-like receptors (TLRs). Two MEVs were optimized for codon and were linked with adjuvants that could bind with TLR4 or TLR2 (TLR4-laterosporulin and TLR2-PorB). Physicochemical properties, allergenicity, toxicity, and structural stability were evaluated, followed by molecular docking with TLR receptors, molecular dynamic (MD) simulation, in silico cloning, and immune simulations. RESULTS:Both MEVs exhibited favorable biophysical properties and high structural stability. Molecular docking confirmed strong binding affinities with TLR2 and TLR4 receptors, suggesting a robust activation of innate and adaptive immunity. Immunological simulations predicted a potent immune response characterized by high cytokine production and memory cell differentiation. The designed MEV demonstrated approximately 90% global population coverage. CONCLUSIONS:The designed MEVs effectively bridge gaps in existing TB immunization by targeting multiple aspects of M.tb pathogenesis. These in silico leads provide a promising framework for preclinical studies, potentially moving toward a more effective clinical solution against TB.
Mycobacterium haemophilum is a very rare and slow-growing nontuberculous mycobacteria that affects mainly immunocompromised patients. Only 250 cases have been reported in the literature since its discovery in 1978. We report a case of a 69-year-old female with systemic lupus erythematosus and lupus nephritis on mycophenolate mofetil who presented with worsening skin nodules. The presence of lower limb edema and proteinuria further confounds the clinical picture toward a lupus flare. Despite treatment for a lupus flare, she developed high-grade fever and new skin nodules, posing a clinical dilemma. She had multiple subcutaneous nodules with ecchymosis along the bilateral thighs and dorsum of the left hand down to the left index finger and along the ulnar aspect of the left wrist, without periungual erythema. Skin biopsy revealed granulomatous inflammation with numerous acid-fast bacilli. The organism was subsequently identified as M. haemophilum by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry. Clinicians should have a low threshold for suspicion of mycobacterial infection and their cutaneous manifestations in immunocompromised patients. Failure to respond to usual treatments should trigger a skin biopsy in a timely manner. New bacterial identification techniques such as gene sequencing and MALDI-TOF are very useful to identify fastidious organisms and to plot appropriate treatment.
BACKGROUND:Efflux-mediated export of pyrazinoic acid (POA) has been associated with pyrazinamide (PZA) resistance, yet the specific transport components remain incompletely defined. Mycobacterium smegmatis , which exhibits intrinsically high POA efflux, provides a quantitative model to study PZA/POA transport mechanisms. METHODS:Using clustered regularly interspaced short palindromic repeats interference, we silenced three efflux pump orthologs of Mycobacterium tuberculosis in M. smegmatis : MSMEG_5046 ( Rv1250c ), MSMEG_0241 ( Rv0202c /MmpL11), and MSMEG_0232 ( Rv0191c ). Gene knockdown was validated by quantitative reverse transcription polymerase chain reaction, achieving 45.1-, 14.6-, and 4.18-fold repression, respectively. POA export kinetics were assessed after PZA loading (final concentration 6.5 mM; 800 µg/mL) using a colorimetric assay over 0-60 min. Efflux rates were calculated from slope values, normalized to intracellular protein content, and compared across biological replicates using analysis of covariance. RESULTS:All silenced strains showed significant differences in efflux slope compared with controls: MSMEG_5046 ( P = 0.0184), MSMEG_0241 ( P = 0.0497), and MSMEG_0232 ( P < 0.0001). At 60 min, normalized POA export changed by +32% (0.0048 mM POA/protein) for MSMEG_5046 , -89.33% (0.0134 mM POA/protein) for MSMEG_0241 , and -39.33% (0.0059 mM POA/protein) for MSMEG_0232 relative to wild type. MSMEG_0241 and MSMEG_0232 knockdowns reduced both efflux slope and total export, supporting a direct role in POA transport, whereas MSMEG_5046 repression increased efflux, suggesting compensatory activity. CONCLUSION:This protein-normalized, slope-based POA export assay resolves gene-specific contributions within a networked efflux system and prioritizes targeted validation in M. tuberculosis.
BACKGROUND:This protocol describes a study in which we would determine the facilitators and barriers to implementation of innovative integrated service delivery for tuberculosis (TB), community-acquired pneumonia (CAP), and chronic obstructive pulmonary disease (COPD), in southern Nigeria. METHODS:This study will adopt a cross-sectional study design using qualitative data collection methods. It will involve key informant interviews (KIIs) for program managers and health service providers, including Directly Observed Treatment Short-course focal persons, radiographers and private care providers. Focus group discussions (FGDs) will be conducted for beneficiaries of the intervention and will include persons diagnosed and treated for TB, CAP or COPD. The study will be conducted in five hard-to-reach Local Government Areas (LGAs) in two states in Southern Nigeria. The LGAs selected for the study have perennial low TB case notifications, which may be attributed to poor active case finding. A total of twenty KIIs and four FGDs will be conducted. RESULTS:In Nigeria, funding for single-disease programs is diminishing, hence unsustainable, making it necessary to adopt more cost-efficient approaches, including integrated service delivery, especially at the primary health care level. CONCLUSION:The findings from this study will help in understanding the factors that influence the implementation of TB/CAP/COPD services and also inform policy/practice on the most suitable approaches to scale up the integrated service delivery for TB/CAP/COPD in Nigeria.
Nontuberculous mycobacterial pulmonary disease (NTM-PD) is a chronic and challenging infectious condition with rising global prevalence, and its bronchiectatic subtype is particularly difficult to treat with conventional regimens due to frequent adverse effects, thus necessitating novel therapeutic approaches. This report presents a 42-year-old female patient diagnosed with bronchiectatic NTM-PD, characterized by persistent cough, sputum production, and hemoptysis, which was confirmed through radiological findings and microbiological testing. Following intolerance to conventional antimicrobial therapy, the patient was treated exclusively with nebulized inhalation of human umbilical cord mesenchymal stem cell-derived exosomes (HucMSC-Exos). This intervention led to significant alleviation of respiratory symptoms, stabilization of pulmonary function, and marked improvement in immunological parameters. In conclusion, nebulized HucMSC-Exos therapy demonstrated successful outcomes in this case, improving clinical symptoms, pulmonary function, and immune status, which suggests its potential as a viable and innovative therapeutic strategy for managing this complex condition and warrants further clinical investigation.
Dermal leishmaniasis, particularly postkala-azar dermal leishmaniasis (PKDL), is an uncommon entity that may closely mimic lepromatous leprosy in endemic regions. Both conditions present with chronic, symmetric nodular or plaque-like lesions, leading to frequent diagnostic confusion, especially when peripheral nerve thickening is absent. We report a 71-year-old male with a 15-year history of diffuse erythematous nodules and scaly plaques over the palms and dorsum of the feet, repeatedly managed as lepromatous leprosy without clinical improvement. The absence of peripheral nerve thickening and a negative slit-skin smear prompted further evaluation. Skin biopsy demonstrated macrophages packed with Leishmania donovani (LD) bodies, and polymerase chain reaction (PCR) targeting the ITS-1 gene confirmed LD. The patient was initiated on miltefosine 50 mg twice daily for 12 weeks (standard regimen). At 4-week follow-up, lesions showed approximately 30% flattening, and at 12 weeks, more than 60% regression was noted, without adverse effects. This rare case of a 71-year-old male with >15 years of misdiagnosis highlights that chronic diffuse nodular dermatosis without nerve involvement should prompt consideration of PKDL even in the absence of documented prior visceral leishmaniasis. Accurate diagnosis using histopathology and PCR prevents prolonged inappropriate therapy and reduces the risk of community transmission.
Background: Species-specific antimicrobial susceptibility testing is crucial for the effective treatment of nontuberculous mycobacteria (NTM). In this study, the in vitro antimicrobial activities of two next-generation antibacterial agents, tedizolid (TZD) and omadacycline (OMC) – which have demonstrated strong in vitro activity against NTM species but have not been comprehensively evaluated for NTM treatment in Turkiye – were investigated. Methods: In this study, antibiotic susceptibility testing for TZD and OMC was performed on a total of 104 NTM isolates (59 rapid-growing and 45 slow-growing) using the colorimetric microdilution method, in accordance with Clinical and Laboratory Standards Institute (CLSI) M24 and M62 standards. Minimum inhibitory concentration (MIC) ranges were 0.015–32 µg/ml for TZD and 0.003–64 µg/ml for OMC. For the interpretation of TZD susceptibility, the CLSI M62 breakpoints established for linezolid were used (≤8 µg/ml: susceptible, 16 µg/ml: intermediate, and ≥32 µg/ml: resistant). Results: Among the rapidly growing NTM isolates, only one Mycobacterium fortuitum isolate was found to be intermediate (1/29; 16 µg/mL), while one Mycobacterium avium isolate among the slowly growing species was classified as resistant (1/6; ≥32 µg/mL). The remaining 102 isolates were all found to be susceptible to TZD (≤8 µg/mL). Since no standardized breakpoint has yet been established for OMC, only the observed MIC values were reported. Conclusions: The findings demonstrated that TZD exhibits strong in vitro activity against NTM isolates, whereas OMC showed a variable activity profile, particularly among rapidly growing species. These results support the necessity of basing antibiotic selection for the treatment of NTM infections on species-specific susceptibility testing.
