Acid-fast Research Articles

FIVE YEARS OF PARTULA SNAIL PRE-EXPORT HEALTH SCREENING.

Between 2015 and 2019, a health screening was carried out annually on captive-bred Partula snails prior to export for reintroduction as part of an international effort to repopulate areas of French Polynesia, where the snails were extinct or critically endangered. In total, 129 separate tank populations of 12 different species were screened at ZSL London Zoo. Wet mounts and smears stained with modified Ziehl-Neelsen (MZN) of 535 fecal samples were examined, and 45% contained flagellated protozoa, and 35.5% had MZN-positive oocysts, measuring 3-5 µm in diameter. Smaller (2 µm) presumptive spores, MZN-positive bacilli, ciliated protozoa and nematodes were recorded less frequently. Fecal bacterial culture yielded mixed species, with a clear predominance of Myroides species (88.9% of samples). The MZN-positive oocysts (3-5 µm) were present in 6.5% of impression smears from the apices of 432 snails examined postmortem, plus acid-fast bacilli in a few cases, but no 2 µm spores. Mixed bacteria were cultured from coelomic swabs, with Myroides species again the most common (63.5%). Histologic examination was carried out on 292 snails. Autolysis affected almost 90% of those found dead but only 3.4% of euthanized snails. Histology commonly identified microsporidial sporocysts in the digestive gland and midgut epithelium of all but two species. Intracellular, extracytoplasmic Cryptosporidium-like organisms were also common in the midgut but were only observed when snails were fixed in 10% formalin (2017-2019), not ethanol. There were no clear pathologic changes associated with either organism. Pigmented hemocytic nodules were commonly observed, most frequently in the foot process; these were either age related or evidence of prior chronic inflammatory reaction and of low clinical significance. With no evidence of poor health and no significant organisms found, a total of 4,978 individuals representing 12 species were exported for reintroduction.

Summary of the clinical characteristics of tuberculous otitis media

Objective:The purpose of this study was to analyze and summarize the clinical characteristics and diagnostic methods of tuberculous otitis media（TOM）, to enrich clinical experience in diagnosis and treatment of tuberculous otitis media, so as to reduce missed diagnosis and misdiagnosis, and facilitate timely and effective therapy for better prognosis. Methods:This study retrospectively analyzed the clinical data of patients with tuberculous otitis media who were hospitalized in the Ear ward of our hospital and received surgical treatment from 2008 to 2022. The data of patients' clinical characteristics, radiological examination, intraoperative findings and therapeutic strategies were recorded and summarized. Results:A total of 23 cases （26 ears） of tuberculous otitis media were included in this retrospective study. The most common clinical symptoms were otorrhea（thin odorless fluid）（100%） and conductive hearing loss（100%）, with a high incidence of facial paralysis（23.1%）. It was not sensitive to traditional antibiotic treatment, eg. Levofloxacin （50% effective rate only）, and relapsed soon after drug withdrawal. It was revealed that all the surgical views had gray and white tough granulation tissue hyperplasia（100%）, and 23.1% with caseous necrosis. The purpose of surgery was to clear the lesion, reduce the recurrence rate of suppurative infection, and repair the function （hearing reconstruction or facial nerve decompression） as appropriate. The paraffin pathology of granulation tissue were reported as typical granulomatous inflammation and caseous necrosis with positive acid-fast staining, which was consistent with tuberculosis. Conclusion:It was easily confused by the clinical manifestations of tuberculous otitis media and common chronic suppurative otitis media. When met with the following conditions, we should pay highly attention to suspect tuberculous otitis media: The severity of local manifestations did not match with the length of the disease; with poor tympanic membrane at the early stage with no obvious cholesteatomas, with facial paralysis or hearing loss early onset; insensitive to traditional antibiotic treatment; with extensive granulation appeared in the tympanum and or mastoid cavity, with or without caseous necrosis or dead bone in the early days. The diagnosis should be confirmed based on the acid-fast staining of the histopathological section to detect positive acid-fast bacilli. Meanwhile, multiple laboratory examination methods（such as T-spot and PCR） should be integrated synchronously to help support the diagnosis.

Management of newborns and healthcare workers exposed to isoniazid-resistant congenital tuberculosis in the neonatal intensive care unit

Management of newborns and healthcare workers (HCWs) exposed to congenital tuberculosis (TB) in the neonatal intensive care unit (NICU) has been reported rarely. To outline a contact investigation process for individuals exposed to congenital TB in the NICU and investigate nosocomial transmission. Additionally, to assess the efficacy and safety of window prophylaxis in exposed newborns. A baby, born at a gestational age of 28+ 1 weeks, was diagnosed with isoniazid-resistant congenital TB on the 39th day of admission to the level IV NICU. Newborns and HCWs exposed cumulatively for ≥8h underwent contact investigation and follow-up for a year. Eighty-two newborns underwent contact investigation. All newborns displayed normal chest X-rays, and 42 hospitalized newborns tested negative for acid-fast bacilli stain and Xpert® MTB/RIF assay in their endotracheal sputum or gastric juices. Eighty received window prophylaxis: six of 75 on rifampin experienced mild adverse events, and none of the five on levofloxacin. After 12 weeks, five (6.1%) had a positive tuberculin skin test, all of whom had already received the Bacillus Calmette-Guérin vaccine and tested negative on TB interferon-gamma releasing assay. Of 119 exposed HCWs, three (2.5%) were diagnosed with latent TB infection and completed a four-month rifampin therapy. There was no active TB disease among exposed newborns and HCWs during a one-year follow-up. Timely diagnosis of congenital TB is crucial for minimizing transmission among exposed neonates and HCWs in the NICU setting. In cases of isoniazid-resistant index patients, even premature newborns may consider the use of rifampin or levofloxacin for window prophylaxis.

Nontuberculous mycobacteria infection among Mycobacterium tuberculosis patients attending tuberculosis referral centers in Nasarawa State, Nigeria

Reports of Mycobacterium tuberculosis (MTB) infection are increasing probably because of misdiagnosis and incorrect reporting of NTM in the State leading to inappropriate treatment regimens and deaths as a result of NTM infection than MTBC and has become detrimental especially among immune-compromised individuals. Thus, this study is designed to determine the Prevalence of NTM among Mycobacterium tuberculosis patients attending Tuberculosis Referral Centers in Nasarawa State, Nigeria. A total of 1380 early morning sputum samples were collected and incubated for the detection of mycobacterial growth, those that were positive for Acid-fast bacilli were further tested (SD Bioline) to detect Mycobacterium tuberculosis Complex (MTBC). Growths that were not MTBC but were Acid-Fast Bacilli positive were suggestive of NTM. Of 1380 sputum collected, the overall prevalence of NTM and MTBC were 8.8% and 20.5% respectively in which males had higher prevalence of 9.0% and 20.9% for NTM and MTBC respectively. Patients with No-formal Education showed highest prevalence of 17.6% and 31.3% for NTM and MTBC respectively. In relation to occupation, farmers had higher prevalence of 13.1% and 29.6% for NTM and MTBC respectively. The prevalence of NTM and MTBC was highest among smokers (9,7% and 24.6%) respectively while participants with HIV had higher prevalence of NTM and MTBC than those that were non-reactive (P2=<0.05 and P1=>0.05). Seasonal infections of NTM and MTBC in the State was low during the raining season and higher during the dry season. Strengthening and expansion of clinical and laboratory services to diagnose and manage diseases caused by NTM with MTBC was highly recommended.

Type II Reaction Erythema Nodosum Leprosum: A Case Report

Leprosy, or Hansen's disease, is a chronic granulomatous infectious disease caused by Mycobacterium leprae. This is a case of a 25-year-old male from Micronesia who presented to a hospital in the Midwest with a two-week history of a widespread, nodular, erythematous, painful rash most severe on his lower extremities and sparing only his hands and feet. In addition to the cutaneous manifestations, the patient met the criteria for Systemic Inflammatory Response Syndrome (SIRS) due to his presentation of tachycardia, tachypnea, leukocytosis, and elevated inflammatory markers. A short course of antibiotics, including Piperacillin-Tazobactam and Vancomycin, and IV steroids were started on admission. A skin biopsy taken from the center and edge of a lesion on the patient’s right arm demonstrated acute and chronic granulomatous superficial and deep inflammation with abundant acid-fast bacilli consistent with lepromatous leprosy from a Mycobacterium leprae infection. Once the National Hansen's Disease Center was contacted previous therapies were stopped and a multidrug therapy, consisting of Rifampin, Moxifloxacin, Minocycline, Methotrexate, and Prednisone was started. The multidrug therapy promptly resulting in substantial clinical improvement over the subsequent months. This case emphasizes the significance of early recognition, accurate diagnosis, and timely initiation of appropriate treatment in leprosy management, even in unlikely regions such as the Midwestern United States.

Digital Pathology in the Detection of Infectious Microorganisms: An Evaluation of Its Strengths and Weaknesses Across a Panel of Immunohistochemical and Histochemical Stains Routinely Used in Diagnostic Surgical Pathology.

The diagnosis of some infectious diseases requires their identification in tissue specimens. As institutions adopt digital pathology for primary diagnosis, the limits of microorganism detection from digital images must be delineated. To assess the reliability of microorganism detection from digitized images of histochemical and immunohistochemical stains commonly used in pathology. Original glass slides from 620 surgical pathology cases evaluated for the presence of infectious microorganisms were digitized. Immunohistochemical stains included those for herpes simplex virus (n = 100), cytomegalovirus (n = 100), Helicobacter pylori (n = 100), and spirochetes (n = 80). Histochemical stains included mucicarmine for Cryptococcus spp (n = 20), Grocott methenamine silver for fungi (n = 100), Giemsa for H pylori (n = 100), and Ziehl-Neelsen for acid-fast bacilli (n = 20). The original diagnosis based on the glass slides was regarded as the reference standard. Six pathologists reviewed the digital images. Digital review was generally associated with high (ie, ≥90%) specificity and positive predictive value owing to a low percentage of false positive reads, whereas a high percentage of false negatives contributed to low sensitivity and negative predictive value for many stains. Fleiss κ showed substantial interobserver agreement in the interpretation of Grocott methenamine silver and immunostains for herpes simplex virus, H pylori, and cytomegalovirus; moderate agreement for spirochete, Ziehl-Neelsen, and mucicarmine; and poor agreement for Giemsa. Digital immunohistochemistry generally outperforms histochemical stains for microorganism detection. Digital interpretation of Ziehl-Neelsen and mucicarmine stains is associated with low scores for interrater reliability, accuracy, sensitivity, and negative predictive value such that it should not substitute for conventional review of glass slides.

Correlation of Procalcitonin with Acid Fast Bacilli and Gene Xpert MTB/RIF as a Marker of Treatment Progress in Pulmonary Tuberculosis patients

There are several limitations in using AFB and GeneXpert to evaluate the treatment of TB patients, one of which is influenced by sputum quality. Therefore, an alternative method is needed to help evaluate the treatment of TB patients. This study aimed to analyze the correlation of the Procalcitonin test with AFB and GeneXpert for evaluating the treatment of TB patients and the performance of Procalcitonin as a marker of TB patient treatment progress. A prospective cohort study was conducted from May to September 2022 at the West Nusa Tenggara General Hospital, Indonesia. Sputum and blood samples were collected from 36 patients who were confirmed positive for TB by GeneXpert MTB/RIF examination, then examined for procalcitonin and AFB before being given treatment and after the intensive phase of treatment. Procalcitonin tested with VIDAS Biomerieux and VIDAS BRAHMS PCT kit. Procalcitonin did not correlate with AFB (p=0.064, r= 0.327) and GeneXpert before treatment (p=0.169, r=0.245), but correlated with AFB (p=0.013, r=0.427) and GeneXpert MTB/RIF (p=0.020, r=0.405) after the intensive phase of treatment. Procalcitonin test with a cut-off value of 0.07 detected negative AFB cases after treatment with a sensitivity of 28.6 and a specificity of 96.2%. The procalcitonin cut-off value of 0.07 also detected negative Xpert MTB/RIF after treatment with a sensitivity of 16.7% and a specificity of 100%. The performance of Procalcitonin for detecting negative smear and negative Xpert MTB/RIF after the intensive phase of treatment is classified as having high specificity, but its sensitivity is still low. Future studies are needed to evaluate the performance of Procalcitonin compared to bacterial cultures.

The Slaughter House and the Re-emerging Foodborne Illness with Special Reference to Bovine Tuberculosis

The Slaughter house is the place in which the animals are slaughtered for human consumption. The Slaughter house plays important role in prevention of zoonotic diseases between animals and humans like Mycobacterium tuberculosis as reemerging foodborne illness and also prevent infectious diseases between animals. Bovine Mycobacterium tuberculosis is caused by a species of pathogenic Gram positive, acid fast stain bacteria in the Mycobacteriaceae family. the causative agent bacteria of Bovine tuberculosis as reemerging foodborne illness tuberculosis bacteria has an waxy cover on its surface primarily due to the presence of acid called mycolic which refers the cells impervious to Gram staining, and as a result, the causative agent bacteria of Bovine tuberculosis as reemerging foodborne illness may appear weakly Gram-positive. Acid-fast bacilli by using certain stains called Ziehl Nielsen, or through using stain called fluorescent such as aura mine are used to identify the cause of Bovine tuberculosis as reemerging foodborne illness with a microscope. The Bacteria cause Bovine tuberculosis as a reemerging foodborne illness is aerobic bacteria and needs high concentrations of oxygen. Mainly this bacteria is pathogenic to human and mammal's respiratory system, it infects the lungs. The most diagnostic means for Bovine tuberculosis as a reemerging foodborne illness are the tuberculin skin examination, stain of acid-fast, laboratory culture, and through using polymerase chain reaction method.

Duodenal tuberculosis with gastric outlet obstruction: a case report of successful diagnosis and treatment, with review of literature

BackgroundDuodenal tuberculosis (TB) is extremely rare, and its diagnosis is challenging owing to the lack of specific symptoms and radiological or endoscopic findings. When it leads to gastric outlet obstruction (GOO), diagnosing it accurately and providing appropriate treatment is crucial. However, this is often overlooked.Case presentationA 35-year-old man presented with abdominal pain, fullness, vomiting, and weight loss. Upper gastrointestinal endoscopy and radiography revealed nearly pinpoint stenosis with edematous and reddish mucosa in the D1/D2 portion of the duodenum. Computed tomography (CT) showed the duodenal wall thickening, luminal narrowing, multiple enlarged abdominal lymph nodes, and portal vein stenosis. Conventional mucosal biopsy during endoscopy revealed ulcer scars. We initially suspected stenosis due to peptic ulcers; however, chest CT revealed cavitary lesions in both lung apices, suggesting tuberculosis. Due to the suspicion of duodenal TB and the need to obtain deeper tissue samples, endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) was performed. The tissue sample showed caseating granulomas with multinucleated giant cells, and acid-fast bacilli were positive by Ziehl–Neelsen staining. The patient was diagnosed with duodenal TB and subsequent GOO. Because the patient had difficulty eating, surgical intervention was prioritized over antitubercular drugs, and laparoscopic gastrojejunostomy was performed. The patient started an oral diet on the 3rd postoperative day and began antitubercular treatment immediately after discharge on the 11th day. During the 6th month of treatment, endoscopic examination revealed residual duodenal stenosis; however, the bypass route functioned well, and the patient remained asymptomatic.ConclusionsAn aggressive biopsy should be performed to diagnose duodenal TB. EUS-FNA has proven to be a useful tool in this regard. Both nutritional improvement and antitubercular treatment were achieved early and reliably by performing laparoscopic gastrojejunostomy for duodenal TB with GOO.

Bilateral Ocular Leprosy An Effect By Erythema Nodusum Leprosum : A Case Report

Introduction : Leprosy or Hansen’s disease is an infection caused by Mycobacterium leprae that primarily affects the skin, the peripheral nerves and the eyes, causing chronic granulomatous inflammation.
 Case Illustration : We present a case of lepromatous leprosy with erythema nodosum leprosum of a 47 years old man with bilateral and asymmetrical ocular complications. One year ago patient consumed multidrug therapy for leprosy for one year but didn’t finish the medication. On the right eye diagnose with chronic anterior and intermediate uveitis, on the left eye with panuveitis. Best corrected visual acuity (BCVA) was 2/60 for right eye and light perception for left eye. Intraocular pressure were within normal limits. Madarosis and corneal hypoesthesia were found on both eyes. On the right eye was found cells, synechia anterior and posterior, iris pearls and vitreous haze. On the left eye was found plasmoid iridocyclitis and vitreous opacities from USG. Slit skin smear (SSS) result positif acid fast bacilli (AFB) dan granular. Patients were treated with multidrug therapy for leprosy, topical antibiotics, atropine and steroids, oral antibiotics and treatment from a dermatologist.
 Discussion : The diagnosis of lepromatous uveitis (LU) in this patient is made through skin tissue biopsy and ophthalmological examination. The effective management of ocular leprosy depends on early diagnosis and appropriate treatment. Hence it is imperative for ophthalmologist to recognize the ocular clinical signs associated with leprosy.
 Conclusion : Most blindness and impaired vision resulting from leprosy is preventable. A multidisciplinary approach is to be taken in order to improve the prognosis.

Comparison of 3 diagnostic methods for pulmonary tuberculosis in suspected patients with negative sputum smear or no sputum.

To explore the diagnostic value of 3 methods for sputum smear-negative and non-sputum patients with suspected pulmonary tuberculosis (TB). This prospective study enrolled sputum smear-negative and non-sputum patients with suspected TB admitted to Jiangxi Chest Hospital between January 2020 and December 2022. The 3 methods were bronchoalveolar lavage fluid (BALF)-acid-fast bacillus (AFB) smear, GeneXpert MTB/RIF, and gene chip for Mycobacterium strain identification. The diagnostic performance of the 3 tests was evaluated with BALF Mycobacterium culture + BALF-AFB smear + GeneXpert MTB/RIF + Gene chip as the gold standard. A total of 456 samples were collected from 114 patients with suspected TB. Twenty-four patients were diagnosed with TB. The combination of GeneXpert MTB/RIF and gene chip for Mycobacterium strain identification yielded the highest area under the receiver operating characteristics curve (AUC) of 0.953 and had sensitivity of 90.57%, specificity of 100%, positive predictive value (PPV) of 100%, negative predictive value (NPV) of 92.42%, accuracy of 95.61%. GeneXpert MTB/RIF achieved AUC of 0.906, sensitivity of 81.13%, specificity of 100%, PPV of 100%, NPV of 85.92%, accuracy of 91.23%. BALF-AFB smear had AUC of 0.519, sensitivity of 3.77%, specificity of 100%, PPV of 100%, NPV of 54.46%, and accuracy of 55.26%. The combination of GeneXpert MTB/RIF and gene chip for Mycobacterium strain identification yielded the highest κ of 0.911, while BALF-AFB smear had the lowest κ value of 0.040. For TB in sputum smear-negative and non-sputum patients using BALF Mycobacterium culture + BALF-AFB smear + GeneXpert MTB/RIF + Gene chip as the gold standard, BALF-AFB smear showed low diagnostic performance, while, though GeneXpert MTB/RIF and gene chip had good diagnostic performance, combining GeneXpert MTB/RIF and gene chip improved the diagnostic value to a great extent.

Disseminated Tuberculosis Revealed by Conus Medullaris Tuberculoma

A 29-year-old man from Comoros presented with rapidly progressive paraplegia and sexual dysfunction. Magnetic resonance imaging (MRI) showed a contrast-enhanced conus medullaris lesion. Differential diagnoses included tumors, abscesses, and inflammatory diseases. Neurosurgery was delayed to complete examinations. Cerebral MRI showed three abscesses. Body computed tomography scan showed supracentimetric polyadenopathies, pulmonary nodules, prostatic lesion, and enhanced seminal vesicle, with hypermetabolism on positron emission tomography with 2-deoxy-2-[fluorine-18]fluoro-D-glucose scan. Histology of lymph node biopsy showed granulomatous infiltration without acid-fast bacilli, and positive polymerase chain reaction for Mycobacterium tuberculosis. Lymph node culture was positive after 2 months, urine culture after 3 weeks, but cerebrospinal fluid and sputum cultures were negative. A 1-year antituberculosis therapy was initiated, associated with corticosteroids because the patient developed tuberculosis-immune reconstitution syndrome, revealed by the recurrence of neurological symptoms. After 2 months the patient completely recovered and could run. MRI showed stability of the voluminous tuberculoma with decrease of medullary edema. Avoiding surgery in those cases may prevent iatrogenic neurological deterioration.

Rare Extrapulmonary Tuberculosis: Covert symptoms and Diagnostic Dilemma.

Pulmonary tuberculosis may result in haematogenous and lymphatic extension in case of failure of early detection, or immunocompromised status, leading to extrapulmonary tuberculosis. Rare sites of extrapulmonary tuberculosis include the gastrointestinal tract, musculoskeletal system, genital tract, middle ear and pericardium. Histopathological findings of macro-confluent granuloma with or without caseous necrosis, along with detection of acid-fast bacilli (AFB) on Ziehl-Neelsen (ZN) staining, and GeneXpert for detection of Mycobacterium tuberculosis DNA, are key in establishing a diagnosis of tuberculosis. Biopsy-proven extrapulmonary granulomatous lesions were included in this study. Histopathological evaluation of all extrapulmonary biopsy specimens sent to the Department of Pathology were done for the presence of granuloma and necrosis, and ZN staining for AFB was done in all the cases of granulomatous lesions with or without the presence of necrosis. The same cases, with biopsy specimens sent in normal saline, were re-evaluated in a molecular laboratory with the help of GeneXpert MTB to detect the DNA of Mycobacterium tuberculosis. All biopsy specimens from extrapulmonary sites which were sent to the Department of Pathology were used for DNA extraction. Out of the 10 cases of extrapulmonary granulomatous lesions, 8 showed caseous necrosis on microscopy, and 7 showed the presence of acid-fast bacilli on Ziehl-Neelsen staining. GeneXpert detected DNA of Mycobacterium tuberculosis in 9 cases. Extrapulmonary tuberculosis rarely occurs as primary, and mostly spreads from lung parenchyma via a haematogenous route. Tuberculosis of the gastrointestinal tract, peritoneum, lymph nodes, and solid viscera are together termed abdominal tuberculosis. Entities like tuberculosis of the pericardium and ear are extremely rare. Extrapulmonary tuberculosis should be a differential in cases of chronic non-responding cases with diagnostic dilemmas. To avoid diagnostic delay, in cases of high suspicion, one should go for biopsy along with ZN staining for diagnostic confirmation as this is cost-effective, followed by GeneXpert for Mycobacterium tuberculosis in highly suspected cases with absent caseous necrosis and negative ZN staining.

Risk factors for tuberculosis-related death among adults with drug-sensitive pulmonary tuberculosis in Selangor, Malaysia from 2013 to 2019: a retrospective cohort study using surveillance data

ObjectivesDue to the paucity of literature on risk factors for tuberculosis (TB)-related death, we determine the sociodemographic and clinical risk factors associated with TB-related deaths among adult pulmonary TB (PTB)...

Retrospective validation of MetaSystems' deep-learning-based digital microscopy platform with assistance compared to manual fluorescence microscopy for detection of mycobacteria.

This manuscript presents a full validation of MetaSystems' automated acid-fast bacilli (AFB) smear microscopy scanning and deep-learning-based image analysis module using a probability threshold of 96% including accuracy, precision studies, and evaluation of limit of AFB detection on respiratory samples when the technology is used with assistance. This study is complementary to the conversation started by Tomasello et al. on the use of image analysis artificial intelligence software in routine mycobacterial diagnostic activities within the context of high-throughput laboratories with low incidence of tuberculosis.

Genetic susceptibility to Tuberculosis in an infant with BCG-osis

Mendelian susceptibility to mycobacterial diseases (MSMD) is a group of innate immunity defects characterized by inborn susceptibility to intracellular pathogens. These are due to defects in the interleukin 12-23-interferon gamma y axis. Twenty-three genetic mutations have been identified in this axis, of which mutation in the IL12RB1 gene is the most common genetic defect of MSMD identified. An 11-month-old infant presented with features of axillary lymphadenitis and skin lesions both of which were positive for acid-fast bacilli on Ziehl– Neelsen stain and GeneXpert. Keeping a high index of suspicion of primary immunodeficiency, the child was evaluated further and was diagnosed as a case of MSMD with IL12RB1 gene mutation.

A comparative study of accuracy between gene Xpert (cartridge-based nucleic acid amplification test) and line probe assay in retreatment cases of sputum-positive pulmonary tuberculosis

Abstract Background: Many studies have compared the efficacy of Gene Xpert (cartridge-based nucleic acid amplification test [CBNAAT]) and line probe assay (LPA) techniques; however, a systematic and meticulous comparison of these two techniques is lacking. Objective: To study the accuracy of GeneXpert Mycobacterium tuberculosis (MTB)/rifampicin (RIF) assay and LPA in the detection of MTB complex in smear-positive retreatment cases of pulmonary tuberculosis (TB). Materials and Methods: This diagnostic evaluation study was conducted on 300 retreatment cases of pulmonary TB. The patients who were receiving retreatment were identified by sputum for acid fast Bacilli by Ziehl–Neelsen staining method and were instructed to provide sputum samples for CBNAAT and LPA. These sputum samples were then processed for liquid culture as part of the routine diagnostic procedure. Results: Majority of the patients (52.3%) were of 31–45 years of age. Males (56%) were more than females (44%). Most of the cases were relapse (88%). Ninety-three percent were reactive on sputum culture. Seventy percent had RIF resistance on CBNAAT. Isoniazid and RIF resistance was seen in 69.7% on LPA. 23.3% were sensitive on LPA and 7% had isoniazid resistance. The sensitivity, specificity, positive predictive value, and negative predictive for CBNAAT as compared with LPA were 75%, 100%, 100%, and 22.2%, respectively. Conclusion: Both LPA and CBNAAT are equally effective in detecting MTB in the given sputum sample. However, LPA is preferred over can be very helpful as it can point out the Isoniazid (INH) and Rifampicin (RIF) resistant nature of the bacterium.

Gallbladder tuberculosis: A rare case report with review of literature

Gallbladder tuberculosis (TB) is a rare disease, and it might be challenging to distinguish it from gallbladder cancer on clinical history and radiology. It frequently mimics carcinoma in patients who initially appear with a gallbladder mass. Gallbladder TB is only identified after histology of the resected specimen since radiography lacks pathognomic characteristics. Here, we describe a unique case of gallbladder TB that was incidentally identified when a 49-year-old lady was being evaluated for suspected gallbladder cancer. Histology of the gallbladder exhibits necrotizing granulomatous inflammation with the presence of numerous pink-colored, curved, and beaded acid-fast bacilli that were recognized on the Ziehl-Neelsen stain.

Study of rapid detection of Mycobacterium Tuberculosis through GeneXpert MTB/RIF assay from acid fast bacilli smear-negative specimens in a Tertiary Care Hospital, Biratnagar Nepal

Introduction: Tuberculosis (TB) is an important public health concern around the world. It is well known that acid-fast bacilli (AFB) smear-negative TB cases are a major source of spreading TB to others when left untreated.
 Objectives: Our study aim to detect Mycobacterium tuberculosis (MTB) in AFB smear-negative samples through GeneXpert MTB/RIF assay and also to evaluate the drug resistance patterns towards Mycobacterium tuberculosis in hospitals.Methodology: This descriptive cross-sectional study was conducted among smear-negative presumptive TB patients at a tertiary care center with effect from September 2022 to September 2023 after approval from the Institutional Review Committee of the college. A convenience sampling method was used.
 Results: Out of 653 smear-negative samples, 71 (10.9%) were positive for TB and 17 (2.6%) were rifampicin resistance cases detected by GeneXpert MTB/RIF assay. The cases of tuberculosis were more in age groups between 46->60 years and least in 17-30 years of age. Pulmonary samples yielded a higher number of MTB 66 (92.95%) as compared to extra-pulmonary samples 5 (7.04%). There is an almost equal proportion of mycobacterium infection in males 37(52.11%) and females 34(47.88%). All the rifampicin resistance cases detected in our study were from pulmonary samples.
 Conclusion: Our study shows that the sensitivity of GeneXpert MTB/RIF assay is higher than AFB smear microscopy. We are missing actual TB cases while using AFB smear microscopy only. Hence the GeneXpert MTB/RIF assay is important for the rapid detection of MTB in smear-negative as well as smear-positive drug resistance MTB cases.

Performance Evaluation of No-Code Artificial Intelligence Models for the Detection of Acid-Fast Bacilli: A Comparative Analysis of Three Models.

Background Acid-fast bacilliMycobacterium tuberculosis and Mycobacterium lepraeare the causative organisms behind two major diseases of developing nations, tuberculosis and leprosy, respectively. To efficiently tackle these diseases in developing nations, drugs must be augmented with improved detection modalities. This necessitates the development of enhanced toolsthat can aid the current detection modalities being used in high-incidence areas. A no-code artificial intelligence model based on image classification is one such tool that can be used in the identification of acid-fast bacilli. This study utilizes three such no-code artificial intelligence models that originate from three different platformsbut share identical training, testing, and subsequent evaluation. Thereafter, the study is directed at comparing the three models created and identifying the onethat can function as a promising support system for the detection of acid-fast bacilli. Methods To begin with, a total of 1000 images per class, i.e., positive and negative for each disease, were captured from the diagnosed slides of tuberculosis and leprosy, taken from the Department of Pathology. Subsequently, these slides were reviewed again by a pathologistto demarcate them as positive or negativefor acid-fast bacilli. Once the required number of images was captured, 600 images of each class were selected as the training set, 300 images as the testing set, and the remaining 100 images as the evaluation set. Data augmentation was then performed using techniques such as rotating, mirroring, cropping, and position shifting. These designated data sets were then used to train the image classification software available on the following three platforms: Lobe (Microsoft Corporation, Redmond, Washington, United States), Create ML (Apple Inc., Cupertino, California, United States), Python-based open-source software (PerceptiLabs, Stockholm, Sweden). The final evaluation was based on different parameters such as sensitivity, specificity, ease of use, learning curve, technological resources required, and feasibility of implementation. All parameters put togetherserved the purpose of comparisonto identify the most promising model. Results Out of the three models tested, the one built using Lobe is the most promisingin terms of the evaluation parameters considered. For tuberculosis, the sensitivity and specificity values obtained were 96% each, while for leprosy, they were 100% and 96%, respectively. Also, the model built using Lobe had a near-negligible learning curve, in addition to being the most cost-effective and feasible model to implement. Furthermore, it had a unique real-time training feature, which constantly improved the model throughout the testing period, till the final sensitivity and specificity values were achieved. Conclusions In clinical situations where a high number of cases are encountered each day, a no-code artificial intelligence model built using Lobe would get exposed to a huge database, getting trained in real time. Subsequently, such a model would reach considerable levels of sensitivity and specificity and in turn, act as a promising support system for the detection of acid-fast bacilli.