Challenging the gold standard: the limitations of molecular assays for detection of Mycobacterium tuberculosis heteroresistance.

OBJECTIVES: Heteroresistant infections are defined as infections in which a mixture of drug-resistant and drug-susceptible populations are present. In Mycobacterium tuberculosis (M. tb), heteroresistance poses a challenge in diagnosis and has been linked with poor treatment outcomes. We compared the analytical sensitivity of molecular methods, such as GeneXpert and whole genome sequencing (WGS) in detecting heteroresistance when compared with the 'gold standard' phenotypic assay: the agar proportion method (APM). METHODS: Using two rounds of proficiency surveys with defined monoresistant BCG strains and mixtures of susceptible/resistant M. tb, we determined the limit of detection (LOD) of known resistance associated mutations. RESULTS: The LOD for rifampin-R (RIF-R) detection was 1% using APM, 60% using GeneXpert MTB/RIF, 10% using GeneXpert MTB/RIF Ultra and 10% using WGS. While WGS could detect mutations beyond those associated with RIF resistance, the LOD for these other mutations was also 10%. Additionally, we observed instances where laboratories did not report resistance in the majority population, yet the mutations were present in the raw sequence data. CONCLUSION: The gold standard APM detects minority resistant populations at a lower proportion than molecular tests. Mycobacterium bovis BCG strains with defined resistance and extracted DNA from M. tb provided concordant results and can serve in quality control of laboratories offering molecular testing for resistance. Further research is required to determine whether the higher LOD of molecular tests is associated with negative treatment outcomes.

Effectiveness of Adjunctive High-Dose Infliximab Therapy to Improve Disability-Free Survival Among Patients With Severe Central Nervous System Tuberculosis: A Matched Retrospective Cohort Study.

BACKGROUND: Few treatment options exist for patients with severe central nervous system (CNS) tuberculosis (TB) worsening due to inflammatory lesions, despite optimal antitubercular therapy (ATT) and steroids. Data regarding the efficacy and safety of infliximab in these patients are sparse. METHODS: We performed a matched retrospective cohort study based on Medical Research Council (MRC) grading system and modified Rankin Scale (mRS) scores comparing 2 groups of adults with CNS TB. Cohort A received at least 1 dose of infliximab after optimal ATT and steroids between March 2019 and July 2022. Cohort B received only ATT and steroids. Disability-free survival (mRS score ≤2) at 6 months was the primary outcome. RESULTS: Baseline MRC grades and mRS scores were similar between the cohorts. Median duration before initiation of infliximab therapy from start of ATT and steroids was 6 (IQR: 3.7-13) months and for neurological deficits was 4 (IQR: 2-6.2) months. Indications for infliximab were symptomatic tuberculomas (20/30; 66.7%), spinal cord involvement with paraparesis (8/30; 26.7%), and optochiasmatic arachnoiditis (3/30; 10%), worsening despite adequate ATT and steroids. Severe disability (5/30 [16.7%] and 21/60 [35%]) and all-cause mortality (2/30 [6.7%] and 13/60 [21.7%]) at 6 months were lower in cohort A versus cohort B, respectively. In the combined study population, only exposure to infliximab was positively associated (aRR: 6.2; 95% CI: 2.18-17.83; P = .001) with disability-free survival at 6 months. There were no clear infliximab-related side effects noted. CONCLUSIONS: Infliximab may be an effective and safe adjunctive strategy among severely disabled patients with CNS TB not improving despite optimal ATT and steroids. Adequately powered phase 3 clinical trials are required to confirm these early findings.

Mucormycosis-A clinicoepidemiological review of cases over 10 years.

BACKGROUND: Limited data exist for epidemiology and outcomes of various agents causing mucormycosis in various clinical settings from developing countries like India. OBJECTIVES: To study the epidemiology and outcomes of various agents causing mucormycosis in different clinical settings in a tertiary care hospital from South India. PATIENTS AND METHODS: We reviewed details of 184 consecutive patients with culture-proven mucormycosis with consistent clinical syndrome and supporting features from September 2005 to September 2015. RESULTS: The mean age of patients was 50.42 years; 70.97% were male. Unlike developed countries, R microsporus (29/184; 15.7%) and Apophysomyces elegans (20/184; 10.8%) also evolved as important pathogens in addition to R arrhizus in our setting. Paranasal sinuses (136/184; 73.9%) followed by musculoskeletal system (28/184; 15.2%) were the common areas of involvement. Apophysomyces elegans typically produced skin and musculoskeletal disease in immune-competent individuals with trauma (12/20; 60%) and caused significantly lower mortality (P = 0.03). R microsporus was more common in patients with haematological conditions (25% vs 15.7%) and was less frequently a cause for sinusitis than R arrhizus (27.58% vs 10.9%). The overall mortality was 30.97%. Combination therapy with surgery and antifungals offered the best chance for cure. CONCLUSIONS: Agents causing mucormycosis may have unique clinical and epidemiological characteristics.

Spoligotyping of Mycobacterium tuberculosis isolates at a tertiary care hospital in India.

OBJECTIVE: Spoligotyping is a valuable genotyping tool to study the genetic diversity and molecular epidemiology of Mycobacterium tuberculosis (M. tb). The aim of this study was to analyse different spoligotype patterns of M. tb strains isolated from patients with tuberculosis from different parts of India. MATERIALS AND METHODS: A total of 163 M. tb isolates were spoligotyped between January 2014 and January 2015. About 47% (n = 77) were from patients with extrapulmonary tuberculosis; of these, 10 were MDR, and seven were Pre-XDR. Of the 86 M. tb isolates from patients with pulmonary tuberculosis, 25 were MDR, and 25 were Pre-XDR. RESULTS: We found 61 spoligo patterns, 128 clusters in the spoligotype data base (spoldb4 data base) with spoligo international type (SIT) number and 35 true unique isolates. The most pre-dominant spoligotype was EAI lineage (56), followed by Beijing (28), CAS (20), T(9), U(7), X(3), H(3), BOVIS_1 BCG(1) and LAM(1). CONCLUSION: Although our study identified EAI, CAS and Beijing strain lineages as pre-dominant, we also found a large number of orphan strains (20%) in our study. Beijing strains were more significantly associated with MDR TB than CAS and EAI lineages. Further studies on large sample sizes would help to clearly describe the epidemiology of M. tb in India.

Invasive fungal infection following chemotherapy for acute myeloid leukaemia-Experience from a developing country.

The incidence of invasive fungal infections (IFI) is believed to be higher in patients with acute myeloid leukaemia (AML) undergoing chemotherapy in non-HEPA-filtered rooms. The aim of this study is to review the incidence of IFI in a large cohort of patients with AML treated at a single centre in India. Two hundred and twenty-two patients with AML treated with either induction chemotherapy or salvage chemotherapy between 2008 and 2013 were studied retrospectively. IFI was defined as per the revised EORTC-MSG criteria. Data on type of chemotherapy, prophylactic strategies, engraftment (ANC>500), the presence of IFI and survival were collected. IFI was diagnosed in 86 patients (38.7%) with proven IFI in 12 (5.4%). Use of posaconazole prophylaxis (P=.001) was the only factor associated with reduced incidence of IFI. Survival in patients with proven IFI was lower than those without proven IFI, but not statistically significant (59.4% vs 78.5%; P=.139). There is a high incidence of IFI during induction chemotherapy for acute myeloid leukaemia in developing countries. Posaconazole prophylaxis was associated with a significantly lower incidence of IFI. Optimal yet cost-effective strategies for prevention and early diagnosis of IFI are required to improve survival in patients undergoing chemotherapy for AML.

The role of Xpert MTB/RIF assay in the diagnosis of tubercular spondylodiscitis.

PURPOSE: This study aims to assess the accuracy of the Xpert MTB/RIF assay in the diagnosis of tubercular spondylodiscitis and to identify its role in detecting Rifampicin resistance in patients with infective spondylodiscitis. METHODS: A retrospective study including 348 patients suspected to have infective spondylodiscitis was done. Tissue/pus samples obtained were sent for culture, histopathology and Xpert MTB/RIF assay. All patients who were confirmed to have tubercular spondylodiscitis and those patients who were suspected on clinico-radiological basis were also treated with anti-tuberculous chemotherapy for a period of 9 months. The efficacy of the Xpert MTB/RIF assay was assessed in terms of sensitivity and specificity when compared to culture, histopathology, and Composite reference standard (CRS). RESULTS: During this study period of 24 months, a total of 348 patients were treated for infective spondylodiscitis. 254 patients were treated for tuberculosis following a smear positivity, culture positivity, and histopathology report or empirically based on clinico-radiological findings. The sensitivity and specificity of the Xpert MTB/RIF assay when compared to culture were 88.4 and 63.7%, respectively. When compared to both culture and histopathology reports it was 80.9 and 80.6%. The sensitivity and specificity of the Xpert MTB/RIF assay when compared to composite reference standard were 71.2 and 100%, respectively. The sensitivity of the assay to detect Rifampicin resistance was 100%. The prevalence of Rifampicin resistance was 5.1%. CONCLUSION: This study recommends Xpert MTB/RIF assay for early detection of Mycobacterium tubercular spondylodiscitis and Rifampicin resistance.

Xpert MTB/Rif for the diagnosis of extrapulmonary tuberculosis--an experience from a tertiary care centre in South India.

OBJECTIVE: The Xpert MTB/Rif, with a detection limit of 131 CFU/ml, plays a valuable role in the diagnosis of extrapulmonary tuberculosis, both susceptible and resistant. This study aims at evaluating the Xpert MTB/Rif for the same, at a tertiary care centre in south India, assessing it against both culture and a composite gold standard (CGS). METHODS: We tested consecutive samples from patients suspected of extrapulmonary tuberculosis with Xpert MTB/Rif, evaluated its sensitivity and specificity against solid and/or liquid culture and CGS. An individual analysis of different sample types (tissue biopsies, fluids, pus, lymph node biopsies and CSF) given an adequate sample size, against both culture and CGS, was also performed. RESULTS: In total, 494 samples were analysed against culture. Compared to culture, the sensitivity of Xpert MTB/Rif was 89% (95% CI 0.81-0.94) and its specificity was 74% (95% CI 0.70-0.78). When Xpert MTB/Rif was compared to the CGS, pooled sensitivity was 62% (95% CI 0.56-0.67) and specificity was 100% (95% CI 0.91-1.00). CONCLUSION: This assay performs better than the currently available conventional laboratory methods. The rapidity with which results are obtained is an added advantage, and its integration into a routine diagnostic protocol must be considered.

Fatal Disseminated Mycobacterium chelonae Infection in an Immunocompromised Host--A Unique Presentation.

Disseminated disease due to rapidly growing non tuberculous mycobacteria especially in the immunocompromised host is being increasingly reported. The usual manifestations of disease being skin and soft tissue infection, post operative wound infection and pulmonary disease. We present a case of a disseminated infection due to Mycobacterium chelonae with features of chronic meningitis and knee joint arthritis in a patient with systemic lupus erythematosus on systemic steroids and mycophenolate. M chelonae was isolated from both synovial and cerebrospinal fluid and anti microbial therapy was initiated as per sensitivity results. However the patient's clinical condition continued to worsen and she succumbed to her illness.

Pott's puffy tumor: An unusual complication of rhino-orbito-cerebral mucormycosis.

Objective: To describe clinicoradiological features and surgical outcomes in a series of nine patients with rhino-orbito-cerebral mucormycosis (ROCM) who presented with Pott's puffy tumor (ROCM-PPT). Methods: The records of nine patients with ROCM-PPT seen between March 2020 and December 2021 were analysed. Clinical features, radiology, histopathology, operative findings, management and outcome were noted. Frontal sinus pneumatisation and outflow tract configuration was compared between patients and controls with ROCM and no PPT. Results: ROCM-PPT was diagnosed in 9 of 284 (3.2 %) patients with ROCM seen during the study period. There were six (66.7 %) males and the median age was 54 (IQR 46-60) years. Eight (88.9 %) patients had diabetes mellitus and seven (77.8 %) had been COVID-19 positive. Radiological features of osteomyelitis, subperiosteal abscess formation and dural enhancement were seen in all patients. No significant differences in pneumatisation or frontal sinus outflow tract configuration were noted between patients and controls. All patients underwent a craniectomy with frontal bone debridement and frontal sinus exteriorisation. All patients were treated with anti-fungal agents for several months. All patients had symptomatic improvement at a median follow-up of 21 (IQR 18-23) months. Repeat CT/MRI scans showed disease regression/resolution in six out of eight (75 %) patients with follow-up imaging, and stable disease in two others. Conclusions: ROCM-PPT is a rare, delayed complication of mucormycosis that was seen in larger numbers during the recent COVID-19 pandemic. Aggressive debridement of osteomyelitic bone and antifungal therapy results in a good outcome.

Short intravenous amphotericin B followed by oral posaconazole using a simple, stratified treatment approach for diabetes or COVID-19-associated rhino-orbito-cerebral mucormycosis: a prospective cohort study.

OBJECTIVES: To evaluate the efficacy and safety of short-course intravenous amphotericin B followed by sustained release posaconazole tablets for diabetes or COVID-19-associated rhino-orbito-cerebral mucormycosis. METHODS: This prospective, pragmatic study included adults with diabetes or COVID-19-associated rhino-orbito-cerebral mucormycosis. Patients received short (7-14 days) or long (15-28 days) intravenous antifungal therapy (short intravenous antifungal treatment [SHIFT] or long intravenous antifungal treatment [LIFT], respectively) depending on the presence or absence of brain involvement. All patients received step-down posaconazole tablets, debridement, and glycemic control. The primary outcome was the treatment success at week 14, which was determined by assessing survival and the absence of disease progression through clinical evaluation and nasal endoscopy. Log-binomial regression analysis (risk ratio and 95% CI) was performed to assess factors associated with the primary outcome. RESULTS: Intravenous therapy was administered to 251 participants: SHIFT, 205 (median duration, 13 days); LIFT, 46 (median duration, 22 days). Treatment success at 3 months was 88% (217/248; 95% CI, 83-91%): SHIFT group, 93% (189/203; 89-96%); LIFT group, 62% (28/45; 47-76%). All-cause mortality was 12% (30/251): SHIFT group, 6% (13/205); LIFT group, 37% (17/46). Age (aRR [95% CI]: 1.02 [1.00-1.05]; p 0.027), diabetic ketoacidosis at presentation (2.32 [1.20-4.46]; p 0·012), glycated haemoglobin A1c (1.19 [1.03-1.39]; p 0.019), stroke (3.93 [1.94-7.95]; p 0·0001), and brain involvement (5.67 [3.05-10.54]; p < 0.0001) were independently associated with unsuccessful outcomes. DISCUSSION: Short intravenous amphotericin B with step-down posaconazole tablets should be further studied as primary treatment option for diabetes or COVID-19-associated mucormycosis in randomized controlled trials.

Feasibility, diagnostic accuracy, and effectiveness of decentralised use of the Xpert MTB/RIF test for diagnosis of tuberculosis and multidrug resistance: a multicentre implementation study.

BACKGROUND: The Xpert MTB/RIF test (Cepheid, Sunnyvale, CA, USA) can detect tuberculosis and its multidrug-resistant form with very high sensitivity and specificity in controlled studies, but no performance data exist from district and subdistrict health facilities in tuberculosis-endemic countries. We aimed to assess operational feasibility, accuracy, and effectiveness of implementation in such settings. METHODS: We assessed adults (≥18 years) with suspected tuberculosis or multidrug-resistant tuberculosis consecutively presenting with cough lasting at least 2 weeks to urban health centres in South Africa, Peru, and India, drug-resistance screening facilities in Azerbaijan and the Philippines, and an emergency room in Uganda. Patients were excluded from the main analyses if their second sputum sample was collected more than 1 week after the first sample, or if no valid reference standard or MTB/RIF test was available. We compared one-off direct MTB/RIF testing in nine microscopy laboratories adjacent to study sites with 2-3 sputum smears and 1-3 cultures, dependent on site, and drug-susceptibility testing. We assessed indicators of robustness including indeterminate rate and between-site performance, and compared time to detection, reporting, and treatment, and patient dropouts for the techniques used. FINDINGS: We enrolled 6648 participants between Aug 11, 2009, and June 26, 2010. One-off MTB/RIF testing detected 933 (90·3%) of 1033 culture-confirmed cases of tuberculosis, compared with 699 (67·1%) of 1041 for microscopy. MTB/RIF test sensitivity was 76·9% in smear-negative, culture-positive patients (296 of 385 samples), and 99·0% specific (2846 of 2876 non-tuberculosis samples). MTB/RIF test sensitivity for rifampicin resistance was 94·4% (236 of 250) and specificity was 98·3% (796 of 810). Unlike microscopy, MTB/RIF test sensitivity was not significantly lower in patients with HIV co-infection. Median time to detection of tuberculosis for the MTB/RIF test was 0 days (IQR 0-1), compared with 1 day (0-1) for microscopy, 30 days (23-43) for solid culture, and 16 days (13-21) for liquid culture. Median time to detection of resistance was 20 days (10-26) for line-probe assay and 106 days (30-124) for conventional drug-susceptibility testing. Use of the MTB/RIF test reduced median time to treatment for smear-negative tuberculosis from 56 days (39-81) to 5 days (2-8). The indeterminate rate of MTB/RIF testing was 2·4% (126 of 5321 samples) compared with 4·6% (441 of 9690) for cultures. INTERPRETATION: The MTB/RIF test can effectively be used in low-resource settings to simplify patients' access to early and accurate diagnosis, thereby potentially decreasing morbidity associated with diagnostic delay, dropout and mistreatment. FUNDING: Foundation for Innovative New Diagnostics, Bill & Melinda Gates Foundation, European and Developing Countries Clinical Trials Partnership (TA2007.40200.009), Wellcome Trust (085251/B/08/Z), and UK Department for International Development.

Chronic Mucocutaneous Candidiasis due to Signal Transducer and Activator of Transcription 1 (STAT 1) Mutation in an Indian Patient - A Case Report.

Chronic mucocutaneous candidiasis (CMC) is a primary immunodeficiency due to defect in various genes leading to an increase in susceptibility to skin and mucosal infection. Mutation in signal transducer and activator of transcription 1 (STAT 1) gene being the most common cause of CMC can lead to increased risk of infections, multisystem abnormalities, and malignancy. We describe a 27 year old Indian woman with clinical features of CMC including esophageal stenosis, gangrene of the finger, endocrinological and immunological abnormalities and STAT1 mutation (p.Leu407Val). She was treated with antifungals which led to symptomatic improvement.

Cryptic aspergillosis: a rare entity and a diagnostic challenge.

Introduction: Cryptic aspergillosis, caused by cryptic species of Aspergillus, is increasingly reported in humans and causes significant morbidity and mortality in immunocompromised individuals. The main aim of this study was to describe the occurrence of this entity at a large tertiary care centre and analyse the challenges in identifying them in a routine diagnostic laboratory. Methods: This was a retrospective case review of all patients diagnosed with cryptic Aspergillus species from April 2019 to February 2020. The isolates were identified using conventional microbiological techniques, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI- TOF MS), 28S rRNA and internal transcribed spacer (ITS) sequencing. Results: The species identified were Aspergillus tamarii, Aspergillus lentulus and Aspergillus sydowii. Identification by MALDI- TOF MS and sequencing was concordant for all except A. sydowii, with MALDI- TOF MS misidentifying it as Aspergillus thermomutans. All isolates showed low minimum inhibitory concentrations (MICs) for the panel of antifungal drugs. Conclusion: Aspergillosis caused by cryptic Aspergillus species presents a diagnostic challenge. This study confirms the importance of molecular methods for accurate identification.

Pulmonary nocardiosis: Risk factors and species distribution from a high burden centre.

Nocardiosis is a clinical and diagnostic challenge. This was a retrospective study carried out on cases of pulmonary nocardiosis presenting over 15 years. Clinical data was retrieved using the electronic patient records. Vitek MS 3.2 (MALDI TOF MS) was carried out on 22 isolates and sequencing on another 9 isolates. Of 71 patients presenting with pulmonary nocardiosis, 58 (81.6%) were on immunosuppressant therapy, 26 (46%) had a previous lung pathology, 11 (8%) were HIV associated. Disseminated disease was seen in 6 (8.4%). There were 8 (11.26%) deaths in this cohort of patients. Of 31/71 identified to species, the most common were Nocardia cyriacigeorgica (n â€‹= â€‹11) followed by Nocardia farcinica (n â€‹= â€‹9).

Effectiveness of a real-time PCR for diagnosis of Pneumocystis pneumonia in immunocompromised patients - Experience from a tertiary care center, India.

Pneumocystis jirovecii pneumonia (PCP) is a life-threatening fungal infection in immunocompromised patients. Traditionally, the laboratory diagnosis of PCP relied on the visualization of organisms by microscopy as Pneumocystis cannot be readily cultured in the laboratory. The polymerase chain reaction (PCR) method is preferred over the conventional microscopic methods as PCR is rapid and found to have higher sensitivity. This retrospective study aimed to analyze the diagnostic value of a real-time PCR (qPCR) for routine diagnosis of PCP in immunocompromised patients with various underlying conditions. The qPCR targets a 121 bp fragment of P.jirovecii mitochondrial large subunit rRNA gene. The study was conducted in a 2600-bed tertiary care hospital between January and December 2019. All patients whose respiratory samples were tested for PCP by qPCR were included. The clinical diagnosis was made for each patient and categorized into PCP and non-PCP based on multi-component clinical criteria by a multi-disciplinary team. The performance characteristics of qPCR were analyzed using clinical diagnosis as the reference. A total of 339 respiratory samples from 289 patients were tested for PCP by qPCR during the study period. The overall sensitivity and specificity of qPCR were 84.75% (95% CI, 73.01% to 92.78%) and 96.1% (95% CI, 92.7 to 98.2), respectively. The sensitivity was slightly higher among HIV-infected patients (91%) than the non- HIV group (81%). The PCR exhibited higher sensitivity in bronchoalveolar lavage (BAL) (94%) than in sputum samples (81%). The colonization can be ruled out with the cycle threshold (CT) value of below 34 with a sensitivity and specificity of 100% and 78%, respectively. The real-time PCR showed good sensitivity and specificity for routine diagnosis of PCP in patients with various underlying conditions. In addition, a cut-off CT value (≤ 34) was determined to exclude colonization from active pneumonia.

Accuracy of Xpert MTB/RIF Ultra for the diagnosis of tuberculosis in adult patients: a retrospective cohort study.

OBJECTIVES: The value of the "trace" result in Xpert Ultra for diagnosing active tuberculosis (TB) remains unclear. Our study evaluated the diagnostic accuracy of Xpert MTB/RIF Ultra (Xpert Ultra) (Cepheid, Sunnyvale, USA) over Xpert MTB/RIF (Xpert) (Cepheid, Sunnyvale, USA) and mycobacterial culture when compared with a composite reference standard (CRS). METHODS: A retrospective single-center observational study was conducted in a tertiary care hospital in South India. Over three months, patients (aged ≥15 years) data on Xpert Ultra tests and mycobacterial culture of pulmonary and extrapulmonary samples were extracted from their electronic medical records. Patients were defined as TB cases based on the CRS criteria. Sensitivity, specificity, positive and negative predictive values of diagnostic tests were calculated by comparing them to the CRS. RESULTS: Xpert Ultra was more sensitive (87.8%) than Xpert (72.1%) and culture (44.1%). The specificity of Xpert Ultra was lower (98.1%) than those of Xpert (100%) and culture (100%). The sensitivity (92%) and specificity (100%) of Xpert Ultra were highest when performed on pus samples. CONCLUSIONS: Xpert Ultra with the trace category is superior to the conventional Xpert, and mycobacterial culture in identifying TB.

Rapid diagnosis of tuberculosis with the Xpert MTB/RIF assay in high burden countries: a cost-effectiveness analysis.

BACKGROUND: Xpert MTB/RIF (Xpert) is a promising new rapid diagnostic technology for tuberculosis (TB) that has characteristics that suggest large-scale roll-out. However, because the test is expensive, there are concerns among TB program managers and policy makers regarding its affordability for low- and middle-income settings. METHODS AND FINDINGS: We estimate the impact of the introduction of Xpert on the costs and cost-effectiveness of TB care using decision analytic modelling, comparing the introduction of Xpert to a base case of smear microscopy and clinical diagnosis in India, South Africa, and Uganda. The introduction of Xpert increases TB case finding in all three settings; from 72%-85% to 95%-99% of the cohort of individuals with suspected TB, compared to the base case. Diagnostic costs (including the costs of testing all individuals with suspected TB) also increase: from US$28-US$49 to US$133-US$146 and US$137-US$151 per TB case detected when Xpert is used "in addition to" and "as a replacement of" smear microscopy, respectively. The incremental cost effectiveness ratios (ICERs) for using Xpert "in addition to" smear microscopy, compared to the base case, range from US$41-$110 per disability adjusted life year (DALY) averted. Likewise the ICERS for using Xpert "as a replacement of" smear microscopy range from US$52-$138 per DALY averted. These ICERs are below the World Health Organization (WHO) willingness to pay threshold. CONCLUSIONS: Our results suggest that Xpert is a cost-effective method of TB diagnosis, compared to a base case of smear microscopy and clinical diagnosis of smear-negative TB in low- and middle-income settings where, with its ability to substantially increase case finding, it has important potential for improving TB diagnosis and control. The extent of cost-effectiveness gain to TB programmes from deploying Xpert is primarily dependent on current TB diagnostic practices. Further work is required during scale-up to validate these findings.

Cryptococcosis with Tuberculosis: Overlooked Coinfections.

Tuberculosis and cryptococcosis are important opportunistic pathogens causing significant morbidity and mortality in immunocompromised individuals. Concurrent infections of these two agents are rarely reported. We report five cases of culture-proven coinfection of Mycobacterium tuberculosis and Cryptococcus neoformans during inpatient admission at a tertiary care hospital in southern India between 2007 and 2019. Four patients were persons living with HIV infection and one was on immune suppression for chronic renal disease. Maintaining a high degree of clinical suspicion will ensure early diagnosis and appropriate management of coinfections in the immunocompromised individual.

Clinical implications of high-risk mutations in drug resistant tuberculosis (DR-TB): An observational cohort study.

Genotype MTBDRsl [SL-LPA] was endorsed as a tool for early diagnosis of fluoroquinolones (FQ) and injectable second-line TB drugs (SLID) resistance in DR-TB. Correlation between specific genetic mutations using this tool and clinical outcome has not hitherto been studied in India. We conducted a observational cohort study to evaluate the predictive value of specific mutations for bad outcome. Our study identified 15 different types of gyrA mutations, commonest being A90V and D94G. Poor outcome was associated with mutations D94G and D94N/D94Y.Most XDR-TB patients harbored the high risk mutation of A1401G. Hence information of specific mutations using SL-LPA can help prognosticate and design appropriate treatment regimens.

Candida utilis: a rare cause of septicemia in children.

Candida utilis is an emerging fungal pathogen in blood. The main aim of this study was to describe the prevalence, methods of speciation and antifungal susceptibility of Candida utilis at a tertiary care centre. METHODS: This was a retrospective study carried out at a tertiary care centre in South India. Over a period of 1 year, three Candida utilis were isolated from blood culture identified by MALDI-TOF MS Version 3.2 and were confirmed by ITS sequencing. Susceptibility testing was carried out by micro broth dilution. RESULTS: All three patients had a common risk factor of prolonged ICU stay but the source of infection could not be identified. Candida utilis isolates were identified by MALDI-TOF and confirmed by ITS sequencing. They were pansusceptible to all tested antifungal drugs. Among these, two patients who were treated in hospital had good clinical outcome and response to antifungal drugs. A third patient was lost to follow up. CONCLUSION: Candida utilis was predominantly seen between 0-3 month olds. Conventional methods of speciation were unable to identify C. utilis to species level. Rapid identification was done by MALDI-TOF MS and confirmed by sequencing. Rapid identification leads to prompt treatment and favours a good clinical outcome.