Acid-fast Bacilli Culture Research Articles

Tuberculosis presenting with multiple osteolytic lesions in an adolescent boy with fanconi anemia

Tuberculosis (TB) is well known to present with varied clinical and radiological features. Multifocal bone involvement in tuberculosis is rare. Multiple lytic lesions raise the possibility of malignancy usually, especially, in children with predisposing conditions like Fanconi anemia. However, a thorough evaluation with repeated attempts at histopathological confirmation and microbiological evaluation is mandatory in children with unique presentations with inconclusive initial diagnostic tests. We report an adolescent boy with an underlying Fanconi anemia who presented with fever, cough and respiratory distress. On evaluation, he had pallor, wasting, features of right upper lobe consolidation and multiple lytic lesions. Initial diagnostic evaluation including bone marrow evaluation and a diagnostic biopsy from ribs and bronchoalveolar lavage failed to yield a conclusive diagnosis. After nearly 5 weeks of broad-spectrum antibiotics and antifungals, as the clinical signs were progressing, a complete re-evaluation including biopsy from the rib lesion was done and further, he was diagnosed to have skeletal tuberculosis based on the Mycobacterium Growth Indicator Tube (MGIT) culture for Acid Fast bacilli (AFB). Child was empirically started on anti-tuberculous therapy pending cultures, which have led to significant clinical improvement in 2 weeks of therapy. Low bacterial load in skeletal TB reduces the chance to diagnosis, hence making clinical judgment imperative in diagnosis; and repeated testing is mandatory when there is high index of suspicion.

Decoding the hidden realm: Molecular pioneering unravelling osteoarticular tuberculosis diagnosis

Osteoarticular tuberculosis (TB), a form of extrapulmonary tuberculosis, refers to the involvement of Mycobacterium tuberculosis (M.tb) in the bones and joints. While pulmonary tuberculosis is the most common form, osteoarticular TB represents a relatively rare but significant manifestation, accounting for approximately 1–3% of all TB cases. Accurate and timely diagnosis plays a pivotal role in the management of osteoarticular TB. Conventional diagnostic methods for osteoarticular TB, such as acid-fast bacilli smear microscopy and culture, have limitations in terms of sensitivity, specificity, and turnaround time. The purpose of this review is to comprehensively evaluate and synthesize the existing literature on molecular pioneering in osteoarticular TB diagnosis. Molecular techniques, such as nucleic acid amplification tests and gene-based assays, have emerged as promising tools for diagnosing TB. These techniques target specific genetic sequences of M.tb, enabling rapid and sensitive detection of the pathogen. However, the diagnostic accuracy, advantages, and limitations of these molecular techniques in the context of osteoarticular TB diagnosis require further investigation and consolidation of evidence. Furthermore, this review aims to identify areas for future research and development in the field of molecular diagnostics for osteoarticular TB.

Role of GeneXpert in the diagnosis of extrapulmonary tuberculosis.

The World Health Organization endorsed the cartridge-based nucleic acid amplification test Xpert MTB/RIF (GXP) for the diagnosis of tuberculosis (TB). Studies about GXP efficiency in extrapulmonary TB (EPTB) are scarce. Hence, we decided to study the role of GXP in EPTB. This prospective observational study, conducted in the pulmonary medicine department of a tertiary care hospital after ethics committee permission, recruited 200 EPTB patients. The diagnosis of TB was achieved with the help of clinico-radiological correlation with microbiological test positivity. Acid-fast bacilli (AFB) culture was treated as the comparative gold standard. Patients who had no or incomplete data were excluded from the study. Data was analyzed to calculate the sensitivity, specificity, positive predictive value, and negative predictive value for the diagnosis of TB and the detection of rifampicin resistance. The majority of cases were women (126 patients: 63%). The mean age was 23.71 years. On GXP, 130 (65%) had detected mycobacterium tuberculosis (MTB), and 70 (35%) did not. Adding AFB culture data, 168 (81.5%) showed microbiological evidence of TB, and 32 (18.5%) were negative. On the drug susceptibility test, 131 cases were rifampicin-sensitive, 32 were rifampicin-resistant TB, and in 5 cases, data was unavailable. The most common extrapulmonary site of involvement was the lymph node, with 94 patients (47%). The most common lymph node involved was the cervical lymph node, with 70 patients (74.5%). The sensitivity, specificity, positive predictive value, and negative predictive value of GXP in EPTB collectively were 76.68%, 86.48%, 96%, and 45.7%, respectively. GXP is useful for the rapid detection of EPTB and the identification of rifampicin resistance, especially in a high-prevalence country like India.

Targeted nanopore sequencing using clinical specimens for the rapid diagnosis of extrapulmonary tuberculosis

BackgroundThe clinical presentation of extrapulmonary tuberculosis (EPTB) is atypical and it is easily confused with other diseases such as common infections, making prompt diagnosis a great challenge. This study aimed to evaluate the accuracy of targeted nanopore sequencing (TNS) in the diagnosis of EPTB. The diagnostic accuracy of TNS using different types of extrapulmonary specimens was also evaluated.MethodsWe reviewed the clinical data of patients with suspected EPTB for whom TNS was conducted and who were hospitalized at our center. The true positive, false positive, false negative, and true negative values were determined. Indices of diagnostic accuracy were computed, including sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and area under the curve (AUC) for TNS and acid-fast bacilli (AFB) culture, and compared with those from clinical diagnosis.Results149 patients were included in the analysis. The overall sensitivity, specificity, PPV, NPV, and AUC of TNS for the diagnosis of EPTB were 86.4%, 87.5%, 97.3%, 55.3%, and 0.87, respectively. For diagnosis by AFB culture, these values were 25.6%, 100.0%, 100.0%, 20.5%, and 0.63, respectively. The most common specimens used were lymph node tissue, cerebrospinal fluid, pleural effusion, and pleural tissue. The diagnostic accuracy of TNS using all types of extrapulmonary specimens was good.ConclusionsTNS demonstrates good diagnostic accuracy in the rapid diagnosis of EPTB and this was true across different types of extrapulmonary specimens.

Diagnostic performance of matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) in bronchoalveolar lavage fluid for pulmonary tuberculosis in HIV-infected patients

IntroductionPulmonary tuberculosis (PTB) remains a significant health concern, particularly in individuals infected with human immunodeficiency virus (HIV) who are more susceptible to developing active TB disease. Early and accurate diagnosis of TB is crucial for effective treatment and prevention of transmission. This study aims to evaluate the potential of matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOFMS) analysis of bronchoalveolar lavage fluid (BALF) for diagnosis of suspected PTB in HIV-infected patients. MethodsThis retrospective study recruited 60 HIV-infected patients with suspected PTB presenting with respiratory symptoms and abnormal chest radiographs between January 2022 and June 2023. BALF samples were collected and subjected to analysis using MALDI-TOF MS, GeneXpert, acid-fast bacilli (AFB) smear and culture. And their diagnostic performance was compared. ResultsThe sensitivity of MALDI⁃TOFMS for diagnosing PTB was 83.3 %, which was better than that of smear 11.9 %, culture 40.5 % or Xpert38.1 % (all p < 0.01). The area under the curve (AUC) value of MALDI⁃TOFMS was 0.889, which was better than that of smear 0.532, culture 0.675 or Xpert 0.690 (all p < 0.01). The katG315 and rpoB-RRDR 511 mutations were detected by the MALDI⁃TOFMS in two patients. ConclusionNucleotide MALDI-TOFMS has a good clinical performance for rapid diagnosis of PTB from BALF samples in HIV infected patients, and detects mutations of TB simultaneously.

Using cerebrospinal fluid nanopore sequencing assay to diagnose tuberculous meningitis: a retrospective cohort study in China

ObjectiveThis study aimed to evaluate the efficiency of nanopore sequencing for the early diagnosis of tuberculous meningitis (TBM) using cerebrospinal fluid and compared it with acid-fast bacilli (AFB) smear, mycobacterial...

Prevalence and Characteristics of Tuberculosis in the Korean Homeless Population Based on Nationwide Tuberculosis Screening.

The government of Korea implemented a strategy of prevention and early diagnosis in high-risk groups to reduce the tuberculosis (TB) burden. This study aims to investigate the TB epidemiology and gap in understanding of TB prevalence among homeless individuals by analyzing active TB chest X-ray (CXR) screening results in Korea. The Korean National Tuberculosis Association conducted active TB screening with CXR for homeless groups from January 1 to December 31, 2021. Sputum acid-fast bacilli smear and culture were performed for the subjects suggestive of TB on CXR. We performed a cross-sectional analysis of the data in comparison with the national health screening results from the general population. Among 17,713 homeless persons, 40 (0.23%), 3,077 (17.37%), and 79 (0.45%) were categorized as suggested TB, inactive TB, and observation required, respectively. Prevalence of suggested TB in the homeless was significantly higher (3-5 fold) than in Univerthe national general health screening based on age category (p&lt;0.005). Twenty-nine cases were confirmed as TB, yielding a prevalence of 164 cases per 100,000 individuals; 19 of these 29 cases showed inactive TB on CXR. Body mass index (p=0.0478) and CXR result (p&lt;0.001) significantly correlated with confirmed TB based on multivariable analysis. Nutrition status and CXR results, especially that of inactive TB, should be considered in active TB screening of the homeless population, where TB prevalence is higher than the general population.

Second Time's the Charm? Assessing the Sensitivity and Yield of Inpatient Diagnostic Algorithms for Pulmonary Tuberculosis in a Low-Prevalence Setting.

For persons with suspected pulmonary tuberculosis, the guidelines of the Centers for Disease Control and Prevention recommend collecting 3 respiratory specimens 8 to 24 hours apart for acid-fast bacilli (AFB) smear and culture, in addition to 1 nucleic acid amplification test (NAAT). However, data supporting this approach are limited. Our objective was to estimate the performance of 1, 2, or 3 AFB smears with or without NAATs to detect pulmonary tuberculosis in a low-prevalence setting. We conducted a retrospective study of hospitalized persons at 8 Massachusetts acute care facilities who underwent mycobacterial culture on 1 or more respiratory specimens between July 2016 and December 2022. We evaluated percentage positivity and yield on serial AFB smears and NAATs among people with growth of Mycobacterium tuberculosis on mycobacterial cultures. Among 104 participants with culture-confirmed pulmonary tuberculosis, the first AFB smear was positive in 41 cases (39%). A second AFB smear was positive in 11 (22%) of the 49 cases in which it was performed. No third AFB smears were positive following 2 initial negative smears. Of 52 smear-negative cases, 36 had a NAAT performed, leading to 23 additional diagnoses. Overall sensitivity to detect tuberculosis prior to culture positivity was higher in any strategy involving 1 or 2 NAATs (74%-79%), even without AFB smears, as compared with 3 smears alone (60%). Tuberculosis diagnostic testing with 2 AFB smears offered the same yield as 3 AFB smears while potentially reducing laboratory burden and duration of airborne infection isolation. Use of 1 or 2 NAATs increased sensitivity to detect culture-positive pulmonary tuberculosis when added to AFB smear-based diagnostic testing alone.

A Rare Case of Tuberculous Constrictive Pericarditis Due to Disseminated Tuberculosis with Response to Anti-tuberculosis Chemotherapy and Steroids in a Developed City State

A 27-year-old man presented with a 1-week history of atypical chest pain and sinus tachycardia. His physical examination was unremarkable. His resting ECG showed sinus tachycardia with widespread T-wave inversion. His initial blood tests show mildly raised troponin T and inflammatory markers and marked raised D-dimer. A CT pulmonary angiogram was performed to exclude pulmonary embolism but incidentally revealed an anterior mediastinal mass. A transthoracic echocardiogram and cardiac MRI showed features of constrictive pericarditis. A video-assisted thoracoscopic surgical biopsy of the anterior mediastinal mass showed thymic tissue with necrotising granulomatous inflammation and an acid-fast bacilli culture was positive to tuberculosis infection. The patient was started on anti-tuberculosis chemotherapy and a 6-week tapering course of oral steroids. A repeat cardiac MRI performed after 6 weeks of treatment showed a significant response to treatment with resolution of constrictive physiology.

Epididymo-orchitis with epididymal abscess in a patient with disseminated tuberculosis

Abstract Tuberculosis remains a global health concern, and while primarily affecting the lungs, extrapulmonary manifestations like genitourinary tubercular epididymitis are rare and diagnostically challenging. Accurate differentiation is crucial for appropriate treatment. This case study presents a 34-year-old male with left scrotal swelling, backache, and fever, highlighting the importance of considering tuberculosis in genitourinary conditions. High-resolution sonography revealed an edematous left testis with increased vascularity and hypoechoic nodules. Further imaging, including high-resolution computed tomography thorax and contrast-enhanced magnetic resonance imaging Dorso-lumbar spine, confirmed disseminated tuberculosis. Despite negative urine culture, aspiration cytology from the epididymal collection indicated tubercular etiology. Urogenital tuberculosis, especially isolated epididymal involvement without renal effects, presents diagnostic challenges, often occurring in immunocompromised patients. The case underscores the role of clinical, biochemical, and radiological evidence in establishing a correct diagnosis. High-resolution ultrasonography plays a crucial role in diagnosing scrotal pathologies, and when accompanied by an epididymal collection, further diagnostic steps involving biochemical parameters and aspiration followed by cytoanalysis and culture are essential. The diagnosis of tuberculous epididymitis can be confirmed through acid-fast bacilli (AFB) identification, positive AFB culture, or granulomas seen in a biopsy specimen in the right clinical context. Radiological imaging aids in detecting local and disseminated disease forms, including complications like hydrocele, testicular calcifications, scrotal abscesses, sinus tracks, and fistulous communications.

Adjuvant surgical resection for nontuberculous mycobacterial pulmonary disease: Effectiveness and complications.

Standard antibiotic treatment for nontuberculous mycobacteria pulmonary disease (NTMPD) has unsatisfactory success rates. Pulmonary resection is considered adjunctive therapy for patients with refractory disease or severe complications, but surgical indications and extent of resection remain unclear. We present surgical treatment outcomes for NTMPD and analyzes risk factors for unfavorable outcomes. We conducted a retrospective investigation of medical records for patients diagnosed with NTMPD who underwent surgical treatment at Asan Medical Center between 2007 and 2021. We analyzed clinical data including microbiological and surgical outcomes. A total of 71 NTMPD patients underwent thoracic surgery. Negative conversion of acid-fast bacillus (AFB) culture following pulmonary resection was observed in 51 (73.9%) patients. In terms of long-term outcomes, negative conversion was sustained in 38 cases (55.1%). Mortality occurred in 7 patients who underwent pulmonary resections for NTMPD. Statistically significant associations with factors for recurrence or non-negative conversion of AFB culture were found in older age (odds ratio [OR] =1.093, 95% confidence interval [CI]: 1.029-1.161, P = 0.004), male sex (OR = 0.251, 95% CI: 0.071-0.892, P = 0.033), and extensive NTMPD lesions involving three lobes or more (OR = 5.362, 95% CI: 1.315-21.857, P = 0.019). Interstitial lung disease (OR = 13.111, 95% CI: 1.554-110.585, P = 0.018) and pneumonectomy (OR = 19.667, 95% CI: 2.017-191.797, P = 0.018) were statistically significant risk factors for postoperative mortality. Pulmonary resection can be an effective adjuvant treatment option for NTMPD patients, with post-operative antibiotic treatment as the primary treatment. Careful patient selection is crucial, considering the associated risk factors and resectability due to complications and recurrence.

Nontuberculosis mycobacteria (NTM) infections in patients with leukemia: a single center case series.

Patients with leukemia experience profound immunosuppression both from their underlying disease as well as chemotherapeutic treatment. Little is known about the prevalence and clinical presentation of nontuberculous mycobacteria (NTM) in this patient population. We identified six cases of NTM infection from 29,743 leukemia patients who had acid-fast bacilli (AFB) cultures. Four cases had bloodstream infections and five had disseminated disease, including one who presented with an unusual case of diffuse cellulitis/myositis. All patients were lymphopenic at time of diagnosis, and two patients ultimately died from their NTM infection. NTM infections are a rare, but potentially life-threatening infection in patients with leukemia. Sending AFB cultures early is important to direct appropriate antimicrobial therapy and allow for future leukemia-directed therapy.

Characteristics of subclinical tuberculosis compared to active symptomatic tuberculosis using nationwide registry cohort in Korea: prospective cohort study.

The clinical manifestations of tuberculosis (TB) range from asymptomatic to disseminated depending on the microbiological and immunological status, making the diagnosis challenging. To improve our understanding of the disease progression mechanism, we aimed to identify the characteristics of subclinical TB and important predictors of symptom development. From July 2018 to June 2019, we systemically collected data from the National Surveillance System of South Korea on patients with pulmonary TB, and compared the characteristics of subclinical and active symptomatic TB patients. A total of 4,636 patients with pulmonary TB were included, and the prevalence of subclinical TB was 37.1% (1,720/4,636). In subclinical TB patients, the positivity rates of acid-fast bacilli (AFB) smear and culture were 16.2 and 50.2%, respectively. Subclinical TB patients were younger (55.6 ± 19.2 vs. 60.7 ± 19.5, P < 0.001), had a higher body mass index (21.7 ± 3.1 vs. 21.0 ± 3.5, P < 0.001), less under Medicaid support, and had lower rates of chronic lung disease, AFB smear and culture positivity, and bilateral disease. Regarding the characteristic differences of individual TB-related symptoms, age was positively associated with dyspnoea and general weakness but negatively associated with chest pain, haemoptysis, and weight loss. Male patients were more prone to weight loss. Chronic lung disease was related to symptoms including cough/phlegm, dyspnoea, and haemoptysis, while autoimmune diseases were associated with fever and weight loss. The development of TB-related symptoms was associated with microbiological burden and clinical characteristics including underlying comorbidities, which should be evaluated carefully.

Value of Acid-Fast Bacilli and Fungal Cultures in Foot and Ankle Surgery in a US Hospital System.

Acid-fast bacilli(AFB) and fungi are generally slow-growing, difficult to culture, and rarely the cause of infection. The goal of this study was to evaluate the value of routinely obtaining AFB and fungal cultures in foot and ankle surgery at a US hospital. A retrospective review was conducted to determine the number of positive AFB and fungal cultures out of the total number of foot and ankle samples tested. Between 2014 and 2019, patients who underwent surgery for a foot and ankle infection for soft tissue infection, septic arthritis, infectious postoperative complications were identified. Charts were reviewed to identify the results of the microbiological tests performed. To determine the value of running AFB and fungal cultures, the costs of each were provided by the microbiology lab at our institution. Of the 322 patient charts reviewed, there were 434 AFB and 525 fungal cultures performed. None of these cultures were indicated to be positive for AFB (0%), and 22 (4.19%) were positive for fungi. The total labor and material costs were calculated to be $38 767. The AFB cultures cost $23 967, the positive fungal cultures cost $2371, and the negative fungal cultures cost $36 395.36. This 322-case series of surgically managed foot and ankle infections showed 0% and 4.1% positivity rates of AFB and fungal cultures, respectively. Additionally, only 20% of cases with positive cultures were identified as pathologic requiring antifungal treatment. Further analysis is needed to determine best practices for obtaining vs declining to culture for AFB or fungal species, including assessing patient outcomes in the series of culture-positive(fungal-only) cases. Our results suggest that in our clinical setting of a US hospital system, routine fungal and AFB cultures may not be necessary but should be considered for chronic/recalcitrant infections, immunocompromised patients, and those with high surgeon suspicion. Level IV, case series.

Usefulness of truenat-derived DNA from extrapulmonary specimens in direct detection of drug resistant tuberculosis by line probe assay

Objectives: Isoniazid (INH) and second-line drug resistance (DR) detection through line probe assay (LPA) takes long in extrapulmonary (EP) specimens because culture growth needs to be obtained to perform deoxyribonucleic acid (DNA) extraction due to the paucibacillary nature of these specimens. Knowing the DR pattern at the earliest is key to success of the treatment. Delay in appropriate tuberculosis (TB) treatment in EP TB patients runs the risk of DR amplification, significant disease damage, and patient loss to follow-up. Here, LPA was attempted on truenat-derived DNA elute from EP specimens, which, in routine, is discarded after the truenat test, to determine drug sensitivity test (DST) for INH and, where necessary, for second-line drugs (Fluoroquinolones, Kanamycin, amikacin, and capreomycin). Material and Methods: Truenat, acid-fast bacilli culture, and fluorescent microscopy were performed on all EP samples that were received at the laboratory during June–September 2022. DNA elute that was left over from 59 truenat Mycobacterium tuberculosis (MTB) positive EP samples were subjected to Genotype MTBDR plus Ver 2.0 assay. Results: MTBDR plus assay (DNA elute) detected MTB and rifampicin (RIF) and INH DST in 47 samples (79.6%) having truenat MTB count of 7.8 × 102 colony-forming unit/milliliter and above. It also detected RIF DST in 65.2% truenat RIF indeterminate samples and DST for both RIF and INH in 60% of culture negative EP specimens. DST results by LPA (DNA elute) completely concorded with standard indirect LPA (on 21 culture isolates from smear-negative specimens). The MTBDRsl yield was however relatively low (11.1%), although second line LPA (SLLPA) was performed only on 9 first-line DR samples. Conclusions: Left-over truenat-derived DNA elute is a significant sample by-product that can significantly speed up and increase the yield of determination of MTB DST in EP samples for RIF and INH, the most critical drugs for TB treatment.

Determination of the diagnostic accuracy of nanopore sequencing using bronchoalveolar lavage fluid samples from patients with sputum-scarce pulmonary tuberculosis

PurposeThe early and efficient diagnosis of patients suspected of having pulmonary tuberculosis (PTB) remains challenging. This study aimed to evaluate the accuracy of nanopore sequencing for PTB diagnosis using bronchoalveolar lavage fluid (BALF) samples and compared it with other techniques such as acid-fast bacilli smear, culture, Xpert MTB/RIF, and CapitalBio Mycobacterium reverse transcription–polymerase chain reaction (MTB RT–PCR). MethodsWe retrospectively analyzed the clinical data of 195 patients with suspected PTB who were admitted to our hospital. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and area under the receiver operating characteristic curve (AUC) of these assays were calculated and compared. ResultsThe overall sensitivity, specificity, PPV, NPV, and AUC of nanopore sequencing were 90.70%, 84.85%, 92.13%, 82.35%, and 0.88; those of acid-fast bacilli smear were 12.40%, 98.48%, 94.12%, 36.52%, and 0.55; those of culture were 36.43%, 100%, 100%, 44.59%, and 0.68; those of Xpert MTB/RIF were 41.09%, 100%, 100%, 46.48%, and 0.71; and those of CapitalBio MTB RT–PCR were 34.88%, 98.48%, 97.83%, 43.62%, and 0.67, respectively. ConclusionThe nanopore sequencing assay using BALF samples showed the best diagnostic accuracy for sputum-scarce PTB. Moreover, it can improve the clinical diagnosis of PTB.

Tuberculous meningitis in Bhubaneswar, Odisha, during 2016 to 2022

BackgroundThe burden of tuberculous meningitis varies substantially by location, and is influenced by the overall burden of tuberculosis in that geographical area, and the age structure of the population. Conventional methods for diagnosis of tuberculous meningitis include acid fast bacilli (AFB) smear and culture. AFB smear has low sensitivity and culture techniques are time consuming. During the last few years, rapid and sensitive molecular methods such as cartridge based nucleic acid amplification technique (CBNAAT) is being used for the diagnosis of tuberculous meningitis. In this study, we evaluated the burden of tuberculosis and rifampicin resistance in suspected cases of tuberculous meningitis in Bhubaneswar, Odisha, during February 2016 to December 2022 using CBNAAT. MethodsUnder the National Strategic Plan 2012–2017, CBNAAT machines were rolled out in 2016, of which 1 was installed in the National Reference Laboratory (NRL) for Tuberculosis in Bhubaneswar. For this study, retrospective data on CBNAAT testing of cerebrospinal fluid (CSF) samples at the NRL was collected and analyzed from February 2016 to December 2022. All the demographic and laboratory data were entered in Excel 2010 (Microsoft office, USA) for data analysis. The age and sex distribution of the presumptive TB patients, proportion of samples referred from public and private health care facilities, proportion of M. tuberculosis positive CSF samples along with sensitivity to rifampicin was evaluated. The study was approved by the Institutional Human Ethics Committee. ResultsDuring February 2016 to December 2022, a total of 1627 CSF samples from presumptive TB meningitis patients were received in the NRL for CBNAAT testing. 60.7% (988/1627) of the presumptive TB patients were males. Of the 1627 patients, 3.1% (50/1627) were positive for M. Tuberculosis by CBNAAT. 56% (28/50) of the patients positive for tuberculous meningitis were males. The positivity for M. tuberculosis varied from 2.1% in 2017 to 5.1% in 2021. The CSF positivity for M. tuberculosis ranged from 0.7% in patients aged >60 years to 6.1% in 15–30 years age group. Of the 50 M. tuberculosis positive samples, 6% (3/50) were resistant for rifampicin. ConclusionOur study which included more than 1600 samples over a period of approximately 7 years found a 3.1% positivity for M. tuberculosis in CSF samples using CBNAAT. 6% of the M. tuberculosis positive samples were resistant to rifampicin. Future studies involving data from other districts of Odisha will help provide a more accurate information on the prevalence of tuberculous meningitis in Odisha state.

INDEX guidelines for extra-pulmonary tuberculosis: knowledge and practice among clinicians in Bengaluru, Karnataka

Background: Extra-pulmonary tuberculosis (EPTB) remains a major problem in developing countries, which acquire diagnostic and management challenges. The study was conducted to characterize the diagnosed EPTB cases, and to understand the perspectives of clinicians on diagnosis and challenges in its management. Methods: A total of 150 EPTB patients' medical records were reviewed at two tertiary hospitals in Bengaluru, Karnataka for the period January 2017 to December 2017. The questionnaire-based interview was conducted among clinicians (n=42) during the study period. Results: The mean age and weight of EPTB patients (females (77, 51%) and males (73, 49%) were 32.5 (±17.5) years and 44.5 (±16.3) kilograms, respectively. Pleural TB (44, 29%), cervical lymph node TB (LNTB) (32, 21%) and abdominal TB (17, 11%) were the most common sites of EPTB involvement, followed by bones and joints TB (11, 7%), spine TB (10, 7%), hilar/mediastinal TB (9, 6%), tuberculoma (8, 5%), TB meningitis (6, 4%), abdominal LNTB (6, 4%), urinary TB (4, 3%) and others (3, 2%). We found GeneXpert was the basis of EPTB diagnosis in 43.3% of cases followed by acid-fast bacilli (AFB) smear microscopy (20.7%) and culture (12.5%). Of 150 EPTB suspected cases, 73% (110) were started anti-TB treatment (ATT), including 8% (12) having received ATT previously. According to LIKERT scale options, 90% of clinicians agreed GeneXpert as a promising diagnostic tool for diagnosis as compared to other microbiological (79%) and histopathological tests (55%). Conclusions: The quality of EPTB diagnosis and management practices at these institutions is satisfactory according to the principles laid down in INDEX TB guidelines or the national guidelines.

Reducing unnecessary testing on sputum specimens from patients with cystic fibrosis: pathology stewardship in microbiology

Chronic respiratory tract infection by Pseudomonas aeruginosa is the hallmark of established lung disease in patients with cystic fibrosis (CF). Antibiotic therapy can usually only suppress but not eradicate infection. In recent years, pulmonary infection with non-tuberculous Mycobacteria (NTM) species has also been increasing. These patients are often colonised with multiple isolates and determination of clinical significance of each isolate is difficult. The clinical value of frequent routine susceptibility testing of individual isolates is unproven, particularly since a delay in susceptibility testing is inevitable when purification of multiple cultured isolates is required to test each isolate separately. From August 2019 until December 2020 we ceased routine susceptibility testing on P.aeruginosa respiratory tract isolates from patients with CF if a previous isolate from the patient had susceptibility testing performed. We found that the proportion of P.aeruginosa isolates that had susceptibility testing performed dropped from 97% to 11% as a result of this change in laboratory process. During this time, we also ceased routine culture for acid-fast bacilli if this had been performed within the previous 6 months. We present the cost and resource savings for these changes in laboratory process and assess for clinical impact measured as hospital admissions, length of stay in hospital and mortality.

Crohn’s Disease and intestinal tuberculosis: allusion and illusion

Differentiating Crohn’s disease (CD) and Intestinal tuberculosis (TB) is a diagnostic dilemma for most of the Clinicians in the developing world where ITB is endemic and CD incidence is increasing. These two granulomatus diseases are remarkably similar in their clinical, endoscopic, radiologic and pathologic features. The only exclusive features are caseation necrosis on biopsy, positive smear for acid-fast bacillus (AFB) and / or AFB culture, and necrotic lymph node on cross-sectional imaging in ITB. These exclusive features are limited by poor sensitivity ( pauci bacillary disease ) and nonspecific diagnostic criteria for CD.However, ITB is potentially curable whereas CD is incurable disease. But rate of misdiagnosis of CD and ITB range between 50% and 70% worldwide. An incorrect diagnosis and treatment may increase complications, morbidity and mortality. A high index of suspicion and critical analysis of clinical, endoscopic, histologic, microbiologic, radiologic and serologic features are required for differentiation between CD and ITB. However, therapeutic anti-tubercular therapy (ATT) trial is still required in a significant proportion of patients to establish the diagnosis. Bangladesh J Medicine 2023; Vol. 34, No. 2(1) Supplement: 196