Acid-fast Research Articles

Diagnostic value of bronchoscopy in sputum‑negative presumptive pulmonary tuberculosis patients and its clinicoradiological profile

Abstract: CONTEXT: Tuberculosis (TB) remains endemic in India. Little local data have been reported on bronchoscopic evaluation of sputum‑negative pulmonary TB patients, which poses a significant diagnostic and therapeutic challenge. AIMS: To determine the diagnostic value of bronchoscopy and bronchoalveolar lavage (BAL) and its clinical and radiological profile in sputum‑negative, pulmonary TB patients. METHODS: We performed an analysis of patients with probable pulmonary TB with overall negative (smear and/or polymerase chain reaction [PCR]) or scanty sputum that had undergone bronchoscopy with BAL over a period of 11 months. Patients’ symptoms, radiological features, lung lobe lavaged, BAL acid‑fast bacilli (AFB) stain, Mycobacterium TB (MTB)‑PCR, and mycobacterial cultures were analyzed. Mycobacterial culture was used as a reference standard. RESULTS: 54 patients underwent a diagnostic bronchoscopy. Dry cough and fever were the most common symptoms. Uncontrolled diabetes mellitus was the most frequent comorbidity identified in 15 (28%) patients. Fifty‑nine percent of the patients had diffuse lung infiltrates, with consolidation being the most common abnormality (41%), followed by cavitation (39%). Right upper lobe was the most frequent lung lobe lavaged (31%). BAL mycobacterial culture and MTB Polymerase Chain Reaction (PCR) were positive in 43 (80%) and 41 (76%) patients and BAL AFB was positive in 5 patients respectively. Using BAL culture as reference, male gender, predominant upper lobe disease, upper lobe lavage, and presence of cavities on chest imaging had the highest diagnosticyield (82%, 100%, 63%, and 89%, respectively) (P = 0.02,0.006, 0.03, and 0.02, respectively).There was 100% concordance among the three diagnostic modalities. CONCLUSIONS: An overall diagnostic yield of 80% was achieved with combined use of BAL MTB PCR, culture, and AFB staining. Keywords: Broncho alveolar lavage, bronchoscopy, Mycobacterium tuberculosis polymerase chain reaction, sputum negative, tuberculosis

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.

Transbronchial brushing cytology and paired biopsy in endobronchial tuberculosis: A report of 72 cases focusing on the morphological features

Objectives: The objectives of this study were to review the transbronchial brushing cytology and histological specimens of endobronchial tuberculosis (EBTB) and to explore the morphological features, diagnostic pitfalls, and dilemmas. Material and Methods: Transbronchial brushing cytology and concurrent biopsy specimens obtained between July 2017 and June 2020 were reviewed. EBTB was confirmed based on the clinical response to the anti-TB treatment in addition to the positive findings of at least one of the following methods: Acid-fast bacilli stain (AFB), auramine-rhodamine stain (A-R), detection of TB bacterial DNA (TB-DNA) by polymerase chain reaction, T-cell spot test (T-spot), and typical pathologic changes of TB on cytology or bronchoscopy biopsy. A total of 72 confirmed cases were studied. Results: Of the 72 patients, 42/72 (58.3%) and 30/72 (41.7%) were female and male patients, respectively. Bronchoscopic findings revealed five subtypes of EBTB, including inflammation infiltration, ulceration necrosis, granulation hyperplasia, cicatrices stricture, and tracheobronchial malacia. AFB, A-R, TB-DNA, and T-spot were positive in 39, 26, 33, and 46 cases, respectively. The detection rate of necrosis in the cytological specimens (90.3%) was significantly higher than that in the biopsy specimens (77.8%; P &lt; 0.01). The percentage of Langhans giant cells detected by cytology (13.9%) was significantly lower than that detected by the pathological examinations of the tissues (38.9%) (P &lt; 0.01). The detection rates of metaplastic squamous cells and epithelioid cells showed no significant difference with respect to the cytology and biopsy findings. In addition to the two patients who had concurrent carcinomas, atypical cells were reported in nine patients through cytopathological diagnosis, among them two were suspected to have carcinomas, two were with the impression that spindle cell neoplasms could not be excluded, and the other five were considered as reactive atypia. Moreover, one biopsy could not rule out the well-differentiated squamous cell carcinoma. Conclusion: Some morphological variations may cause challenges in cytological evaluation. Moreover, diagnostic dilemmas can occur even in the assessments of tissue pathology.

Early Microbiologic Markers of Pulmonary Tuberculosis Treatment Outcomes.

Rationale: Earlier biomarkers of pulmonary tuberculosis (PTB) treatment outcomes are critical to monitor shortened anti-TB treatment (ATT). Objectives: To identify early microbiologic markers of unfavorable TB treatment outcomes. Methods: We performed a subanalysis of 2 prospective TB cohort studies conducted from 2013 to 2019 in India. We included participants aged ⩾18 years who initiated 6-month ATT for clinically or microbiologically diagnosed drug-sensitive PTB and completed at least one follow-up visit. Sputum specimens were subjected to a baseline Xpert Mycobacterium tuberculosis/rifampin (MTB/RIF) assay, acid-fast bacilli (AFB) microscopy and liquid and solid cultures, and serial AFB microscopy and liquid and solid cultures at weeks 2, 4, and 8. Poisson regression was used to assess the impact of available microbiologic markers (test positivity, smear grade, time to detection, and time to conversion) on a composite outcome of failure, recurrence, or death by 18 months after the end of treatment. Models were adjusted for age, sex, nutritional status, diabetes, smoking, alcohol consumption, and regimen type. Results: Among 1,098 eligible cases, there were 251 (22%) adverse TB treatment outcomes: 127 (51%) treatment failures, 73 (29%) recurrences, and 51 (20%) deaths. The primary outcome was independently associated with the Xpert MTB/RIF assay (medium-positive adjusted incidence rate ratio [aIRR], 1.91; 95% confidence interval [CI], 1.07-3.40; high-positive aIRR, 2.51; 95% CI, 1.41-4.46), positive AFB smear (aIRR, 1.48; 95% CI, 1.06-2.06), and positive liquid culture (aIRR, 1.98; 95% CI, 1.21-3.23) at baseline; Week 2 positive liquid culture (aIRR, 1.47; 95% CI, 1.04-2.09); and Week 8 positive AFB smear (aIRR, 1.63; 95% CI, 1.06-2.50) and positive liquid culture (aIRR, 1.54; 95% CI, 1.07-2.22). There was no evidence of Mycobacterium tuberculosis growth in the Mycobacterium Growth Indicator Tube at Week 4 conferring a higher risk of adverse outcomes (aIRR, 1.25; 95% CI, 0.89-1.75). Conclusions: Our analysis identifies Week 2 respiratory mycobacterial culture as the earliest microbiologic marker of unfavorable PTB treatment outcomes.

A case of reversible isolated cognition impairment in meningoencephalitis without abnormal MRI findings

AbstractBackgroundWe report a case of meningoencephalitis with reversible isolated cognition impairment without abnormal MRI findings.MethodA 75‐year‐old man presented with confusion including bizarre behavior 2 days ago. Before visiting the hospital, his son found the patient naked and under the blanket saying it was cold. Fever didn’t occur. Mental status was alert without awareness. On neurologic examination, mutism was found. Muscle power on both upper and lower limbs was normal. Routine laboratory test showed that leukocytes count was normal but eosinophils were increased to 14.0%. Initial brain MRI including DWI and contrast enhanced image revealed no enhanced structural lesions. Initial K‐MMSE score was 4 points while the previous K‐MMSE score 3‐months‐ago was 25 points. There was no epileptic form discharge in EEG. CSF study demonstrated that WBC count was 18/L. protein was 42.6mg/dL, and glucose was 103mg/dL. CSF opening pressure was 5cmH2O. Culture study including gram stain, AFB stain, PAS stain showed no growth of aerobe, anaerobe, fungus and hyphae. Mycobacterium tuberculosis PCR and HSV PCR were negative. ADA was under 3 IU/I. Serum paraneoplastic antibodies were all negative.ResultThe patient showed only isolated cognition impairment without fever and there was no evidence of meningoencephalitis on the contrast enhanced MRI. Although the patient revealed CNS infection with unknown cause in CSF profile, it has some possibilities; 1) Aseptic meningoencephalitis with viral infection, 2) Bacterial meningoencephalitis with early stage, 3) Parasitic meningoencephalitis, 4) Autoimmune meningoencephalitis. Because of the negative findings in autoimmune antibody test, autoimmune meningoencephalitis was less likely. After treatment with acyclovir 0.6g for 7days, ceftriaxone 4g, vancomycin 2.5g and Ampicillin 8g for 10 days, confusion and mutism were improved with K‐MMSE 18 points.ConclusionMany reports have been published on meningoencephalitis accompanied by fever, altered mentality, seizure, muscle weakness and abnormal MRI findings respectively. However there have been few cases of meningoencephalitis with isolated cognition impairment and normal MRI simultaneously. If it is a change of consciousness and cognition impairment caused by meningoencephalitis, it can be reversible with proper treatment. Therefore, if only sudden onset isolated CNS symptom with normal brain MR finding, it is essential to check CSF profile.

Diagnostic performance of two commercial MPT64 assays for the identification of Mycobacterium tuberculosis complex from liquid culture

BackgroundTuberculosis (TB) is a chronic infectious disease caused by bacteria of the Mycobacterium tuberculosis complex (MTBC). Early diagnosis of TB is the most essential component to control TB. In this study, we evaluated the diagnostic performance of SD Bioline TB Ag MPT64 (SD Bioline) and BD MGIT TBc Identification (BD TBc ID) kits for the detection of MTBC from MGIT (Mycobacteria Growth Indicator Tube) 960 culture tube, positive for acid-fast bacilli (AFB). MethodsA total of 198 AFB positive MGIT cultures [MTBC, 150 and non-tuberculous mycobacteria (NTM), 48] were collected during the study period (April 2021 to March 2023) and subjected to SD Bioline and BD TBc ID assays, respectively. All the 150 MTBC positive cultures were confirmed by multiplex PCR targeting MPB64, protein B and IS6110 genes, and the 48 NTM cultures were speciated by using line probe assays technique- Genotype Mycobacterium CM assay. ResultsSD Bioline and BD TBc ID kits detected all 150 MTBC strains correctly from MGIT positive cultures and no false negative was observed. However, there was one false positive for M. abscessus by SD Bioline and two false positive results for M. abscessus and M. intracellulare each by BD TBc ID. Overall, the sensitivity of both SD Bioline and BD TBc ID tests was 100 % and specificity was 97.9 % and 95.8 %, respectively. ConclusionOur results highlighted that SD Bioline and BD TBc ID assays played a promising role in the earlier identification of MTBC present in liquid culture and may act as a potential alternative to biochemical and expensive molecular techniques.

Gross and histopathological features of tuberculosis in cattle, buffalo and spotted deer (Axis axis) caused by Mycobacterium orygis

Mycobacterium orygis has been isolated from several cases of tuberculosis in various species of animal in India but documentation of the histopathological lesions caused by this organism is scant. Lung and liver tissues with caseous nodules from cattle (n = 8), lung samples from spotted deer (Axis axis) (n = 5) and lung and mediastinal lymph node samples from buffalo (n = 9) were subjected to histopathology and isolation of Mycobacterium spp. Isolation was carried out using the BACTEC MGIT 960 Automated Mycobacterial Detection System and acid-fast positive cultures were identified to species level using polymerase chain reaction (PCR) employing published primer pairs. Three M. orygis isolates (two from cattle, one from deer) were obtained, whole genome sequenced and the sequences submitted to the National Center for Biotechnology Information Sequence Read Archive. Eight samples (four cattle, one deer and three buffalo) were confirmed as M. orygis positive by PCR. Histopathological examination of the M. orygis-PCR-positive cattle samples revealed acid-fast organisms in lung sections along with macrophages, epithelioid cells, lymphocytes and Langhans giant cells. Granuloma stages I to IV were seen in the cattle and buffalo samples and stage III in the spotted deer sample. This report is the first description of the gross and histopathological lesions of tuberculosis caused by M. orygis in buffalo and documents the gross and histopathological findings of M. orygis tuberculosis in cattle and deer.

Congenital Pulmonary Airway Malformation Type 1 with Pulmonary Neuroendocrine Cell Hyperplasia in an Adult Male: a Rare Case Report

Abstract Introduction/Objective Congenital pulmonary airway malformations (CPAM) is rare, usually diagnosed in the pediatric population, and may occur in adults. Pulmonary neuroendocrine cell hyperplasia (PNECH) mimicking diffuse idiopathic pulmonary neuroendocrine cell hyperplasia (DIPNECH) associated with CPAM has not been described previously. We report a case of CPAM Type 1 with PNECH. Methods/Case Report A 33-year-old male, with past medical history of latent tuberculosis (TB) by Quantiferon blood testing, recurrent pneumonia, recurrent lung abscesses, and lung cavitary lesion for three years, presented with fever, cough with hemoptysis, shortness of breath, and left-sided chest pain. Computerized tomography of chest displayed a 10.8 cm cavitary lesion in the left lower lobe of the lung. The patient underwent left lower lobectomy of the lung. Grossly, the lobectomy specimen revealed a 10.5 cm irregular cavity communicating to the superior segmental bronchus of the left lower lobe. Microscopically, the dominant large cyst was surrounded by lung parenchyma and small cystically dilated spaces resembling bronchioles under the fibrotic pleura. The large cyst was lined by respiratory epithelium with rare pathognomonic mucous cells in clusters. Cyst walls contained smooth muscle, small islands of cartilage, and focal intense acute and chronic inflammatory cell infiltrates with hemorrhage. There were multiple foci of proliferation of pulmonary neuroendocrine cells centered around bronchioles surrounding the large cyst. The neuroendocrine cells were arranged from individual cells and cellular aggregates to larger tumorlets, highlighted by Synaptophysin and Chromogranin immunostains. No granuloma or necrosis was present. No acid-fast bacilli or fungal microorganisms were identified by special stains. The findings are consistent with CPAM type 1, with PNECH. Results (if a Case Study enter NA) NA Conclusion Our study demonstrates a histologically diagnosed adult congenital pulmonary airway malformations type 1 with an incidental pulmonary neuroendocrine cell hyperplasia, which mimics diffuse idiopathic pulmonary neuroendocrine cell hyperplasia. To the best of our knowledge, this is the first report of such an association.

Utility of nucleic acid amplification test in the detection of tuberculosis in biological fluids from suspected TB patients in a cardiovascular center in the Philippines

BackgroundTB NAAT is highly sensitive and can therefore be a helpful tool used in confirming M. tuberculosis. In a prospective study, we evaluated the utility of TB NAAT in the detection of tuberculosis in biological fluids from suspected TB patients. MethodsWe compared tuberculosis nucleic acid amplification test and acid-fast bacilli smears with Lowenstein-Jensen culture, from patients with a clinical suspicion of tuberculosis disease. We calculated the sensitivity, specificity, PPV and NPV. ResultsUsing the Lowenstein-Jensen culture as the gold standard for detection of Mycobacterium tuberculosis, the TB-NAAT showed sensitivity of 66.67 %, specificity of 93.67 %, and gave a positive predictive value of 44.44 %. ConclusionWe conclude that the TB-NAAT is a quick and consistent diagnostic test for TB detection. However, due to a comparably lower sensitivity than other previous studies, the utility of TB-NAAT alone may not be sufficient in the screening of TB patients. Likewise, the TB-NAAT cannot detect non-tuberculous mycobacteria, for which additional analysis may be needed.

2584. Predictors of Clinically Significant Infection in Patients with Mycobacterium simiae Isolated from Respiratory Samples: a Retrospective Study from a Tertiary Care Center in Lebanon

Abstract Background Mycobacterium simiae is a rare slow-growing, non-tuberculous mycobacterium (NTM). It is predominant in Middle Eastern countries like Israel, Iran and Lebanon and is the most isolated NTM spp. at our institution (40%). Little is known about its reservoirs, pathogenesis, risk factors and indications for treatment. Methods We retrospectively studied patients with respiratory cultures showing M. simiae at the American University of Beirut Medical Center (AUBMC) over 19 years. We used the American Thoracic Society/Infectious Diseases Society of America (ATS/IDSA) criteria to define NTM lung disease. Samples were cultured at AUBMC using Lowenstein-Jensen media and the BacT/ALERT system. NTM isolates were referred for speciation and susceptibility testing at Mayo Clinic, MN, USA. Results We identified 72 isolates from 66 patients. Most were obtained from sputum samples (57.6%), the rest from bronchoalveolar lavages (BAL). Acid-fast bacilli smear was positive in 27% of samples with no difference between sputum and BAL. The median age of patients was 64 years and 51.5% were females. Bronchiectasis (34.5%), chronic obstructive pulmonary disease (27.3%) and immunosuppression (33.3%) were common (Table 1). As per the ATS/IDSA criteria, 67.9% of patients had NTM lung disease. The most common symptoms were cough (83.3%) and sputum production (74.5%). All patients except 2 had abnormal findings on CT imaging like nodules (58.5%), tree in bud aspect (45.3%) and bronchiectasis (24.5%). Among those, 55.6% had abnormal CT findings preceding the M. simiae isolation. Bronchiectasis was more common in those who satisfied the ATS/IDSA criteria versus those who did not (38.9% vs 20.0%). Otherwise, we found no significant differences between both groups (Table 2). Treatment was given to 88.9% of patients who satisfied the NTM lung disease and 42.1% of those who did not (p&amp;lt; 0.001) with a median duration of 12 months. Of those with available follow-up, relapse was reported in 24% of cases. Characteristics of patients with M. simiae isolated from respiratory samples. BMI, body mass index, COPD, chronic obstructive pulmonary disease, AFB, acid-fast bacilli. *Median(Interquartile range) **Composite variable including hematologic malignancy, solid organ malignancy, hematopoietic transplantation, solid organ transplant, chronic steroids treatment, and active chemotherapy. Clinical and radiological differences between patients with M. simiae lung disease and those colonized according to the ATS/IDSA criteria. BMI, body mass index, COPD, chronic obstructive pulmonary disease. *Median (Interquartile range) Conclusion M. simiae is a significant cause of NTM lung disease at our institution with a high rate of relapse. Further research is required to understand its geographic restriction, predisposing factors, and identify patients at risk for clinically significant infection. Disclosures Souha S Kanj, MD, Gilead: Advisor/Consultant|Menarini: Advisor/Consultant|MSD: Advisor/Consultant|Pfizer: Advisor/Consultant

Assessment of geneXpert test for diagnosis of pediatric pulmonary tuberculosis

Introduction: Pediatric tuberculosis is an infectious disease and is a leading cause of death in Nepal. The incidence of pediatric TB is a key tool of ongoing transmission of tuberculosis within the community and vital indicator of disease control. Its diagnosis is very much challenging and delay in diagnosis leads to mortality.&#x0D; Objectives: This study was conducted to assess the utility of the gene Xpert test for diagnosis of pediatric pulmonary tuberculosis.&#x0D; Methodology: A hospital based prospective study done at Pediatric department of a teaching hospital, Nepalgunj, Banke conducted over a period of 1 year from 1 January 2021 to 31 December 2021 with presumptive diagnosis of pediatric pulmonary tuberculosis. Chi-square test was used to determine the association between categorical variables and a receiver operating curve (ROC) analysis was performed to compare the performance of gene Xpert test with other lab parameters like sputum/gastric lavage sample microscopy for acid fast bacilli, erythrocytic sedimentation rate, Tuberculin test (TT) and chest X-ray.&#x0D; &#x0D; Results: We enrolled a total of 294 patients in our study. Out of 294 samples 5.1% samples came out to be positive for gene Xpert for MTB. The sputum/gastric lavage samples for AFB showed both sensitivity and specificity of 100%. The tuberculin test showed a sensitivity of 80% and specificity of 37.3%. Chest X-ray showed a sensitivity of 66.7% and specificity of 43.7%. The area under the curve for acid fast bacilli in microscopy, tuberculin test and ESR was found to be 100% (95% CI: 100%-100%), 58.6% (95% CI: 44.9%-72.4%), and 52.6% (95% CI: 37%-68.3%) respectively. &#x0D; &#x0D; Conclusion: This study highlights the utility of gene Xpert as a good diagnostic tool for rapid diagnosis of pulmonary tuberculosis in pediatric population.

Pulmonary tuberculoma: does persistent imaging lesion equals treatment failure?

Pulmonary tuberculoma is a rare but challenging entity for paediatricians, regarding diagnosis and management. Treatment course is still up for discussion since tuberculomas may persist after treatment. The authors report two paediatric cases, both recently treated for latent tuberculosis infection, admitted for investigation of a solid pulmonary nodule. In both cases the thoracic CT scan showed a nodular subpleural lesion and the biopsy revealed epithelioid cells with areas of necrosis and calcification. The diagnosis of pulmonary tuberculosis was confirmed in one case by detection of acid-fast bacilli in the smear and in the other by nucleic acid amplification test for M. tuberculosis. The patients presented good response to treatment with antituberculosis drugs, without need for surgical resection. These reports highlight the diagnostic and treatment challenges of this rare entity.

Clinical Features, Diagnosis, and Treatment of Congenital and Neonatal Tuberculosis: A Retrospective Study

Introduction: Limited studies have explored the clinical features, treatment, and prognosis of neonatal tuberculosis (TB). Here, we attempted to delineate the clinical characteristics of neonatal TB, which may help clinicians further understand this disease. Methods: A retrospective analysis of neonates diagnosed with congenital and/or neonatal TB disease from January 2010 to December 2020 was performed. Information on the demographic and epidemiological features, clinical symptoms, laboratory and imaging examinations, therapeutic regimens, and outcomes was collected. Kaplan-Meier analysis was used to present the time to disease onset, time to diagnosis, etc. Results: Forty-eight cases of neonatal TB were classified into congenital (n = 33) and postnatal (n = 15). The median time to disease onset in postnatal group was significantly longer than that in congenital group. Positive results for gastric fluid acid-fast bacilli, TB culture, Xpert MTB/RIF, interferon-γ release assay (IGRA), and tuberculin skin test were detected in 26/48 (54.2%), 14/34 (41.2%), 11/18 (61.1%), 19/29 (65.5%), and 8/24 (33.3%) patients, respectively. For lymphadenopathy, computed tomography (CT) scans showed a higher detection rate than did X-ray (80.0% vs. 0). Of the 48 infants, 44/48 (91.7%) received anti-TB therapy, and 33/44 (75%) were clinically improved or cured after 22.1 months (interquartile range: 12.4–27.7) of follow-up. Drug-induced liver injury occurred in 14/44 (31.8%) patients. Discussion/Conclusion: IGRA and Xpert MTB/RIF showed good positive rate in neonatal TB infection/disease. In cases where TB is presumed but etiological evidence is lacking, low-dose CT could be considered. Prompt treatment under careful surveillance is important for preventing mortality and avoiding severe adverse effects.

1882. Contact Investigation of Congenital Tuberculosis in a Neonatal Intensive Care Unit in South Korea

Abstract Background Congenital tuberculosis (TB) is uncommon and difficult to detect in neonates due to its nonspecific symptoms. We conducted a contact investigation of infants and healthcare workers (HCWs) exposed to a neonate with congenital TB in a neonatal ICU (NICU) in Korea. Methods A premature infant born was admitted to NICU on September 16, 2022. On October 24, the infant's mother was diagnosed with miliary TB, and infant’s sputum AFB stain showed 4 positive results. All NICU infants and HCWs during the same period were screened for active pulmonary TB using chest radiography (CXR) immediately. Exposed infants were evaluated with a TST and CXR three months after exposure. Interferon-Gamma Release Assay (IGRA) testing was performed on those with a positive TST or abnormal CXR finding. Prophylactic rifampin was provided to the exposed infants for 3 months, as index had isoniazid-resistant M. tuberculosis infection. Exposed HCWs underwent IGRA testing immediately after exposure (1st IGRA) and at 8 to 10 weeks post-exposure (2nd IGRA), and CXR was performed 6 months after exposure. Results Five out of 82 exposed infants had positive TST (≥ 10 mm) results, while all 31 infants who underwent IGRA testing had negative results. All five with positive TST had received BCG vaccination a median 105 days before. Of the 119 exposed HCWs, three had a conversion; two had negative results (on annual IGRA testing performed according to the national TB prevention Act) before exposure and positive at 1st IGRA test, and one had negative 1st IGRA test then positive 2nd IGRA test. None had active TB during 6-month follow-up. Conclusion We found that 6% of exposed infants had positive TST results and 0% had positive IGRA, while 2.5% of exposed HCWs had conversion. Considering the possibility of false positive TST results due to prior BCG vaccination, the chance of transmission to the infants would be 0%; otherwise, it would be 6.1%. Disclosures All Authors: No reported disclosures

Laparoscopic and hysteroscopic findings in women with sub-fertility and tuberculosis: A case series.

Evaluation of hysteroscopic and laparoscopic findings in subfertile women predictive of tuberculosis. Retrospective case series analysis. Tertiary hospital in India. A retrospective analysis of 16 784 subfertile women who had undergone diagnostic hysterolaparoscopy (DHL) was conducted between February 2014 and June 2021. Histopathological evidence, acid-fast bacilli (AFB), culture and GeneXpert MTB/RIF assay were used to diagnose female genital tuberculosis (FGTB). Various hysteroscopic and laparoscopic findings were analysed, and a binary logistic regression assessed associations between these findings and positive diagnostic outcomes. Various hysteroscopic and laparoscopic findings correspond to tubercular manifestation. Of the 16,784 patients, 1083 had hysteroscopy and laparoscopy findings suggestive of tuberculosis, and 309 were diagnosed with FGTB based on diagnostic tests. Logistic regression identified variables strongly predictive of positive status outcomes; tuberculous abdomino-pelvic adhesions of various grades, isthmo-ampullary block, tubercle, tubo-ovarian mass, tuberculous hydrosalpinx, complete tubal destruction, tubal diverticula and rigid tube emerged as strong predictors. Logistic regression-derived predictors, alongside specific laparoscopic and hysteroscopic findings, can enhance diagnostic accuracy and clinical decision-making to start antitubercular therapy in subfertile women.

A preclinical model of TB meningitis to determine drug penetration and activity at the sites of disease.

Tuberculosis meningitis (TBM) is essentially treated with the first-line regimen used against pulmonary tuberculosis, with a prolonged continuation phase. However, clinical outcomes are poor in comparison, for reasons that are only partially understood, highlighting the need for improved preclinical tools to measure drug distribution and activity at the site of disease. A predictive animal model of TBM would also be of great value to prioritize promising drug regimens to be tested in clinical trials, given the healthy state of the development pipeline for the first time in decades. Here, we report the optimization of a rabbit model of TBM disease induced via inoculation of Mycobacterium tuberculosis into the cisterna magna, recapitulating features typical of clinical TBM: neurological deterioration within months post-infection, acid-fast bacilli in necrotic lesions in the brain and spinal cord, and elevated lactate levels in cerebrospinal fluid (CSF). None of the infected rabbits recovered or controlled the disease. We used young adult rabbits, the size of which allows for spatial drug quantitation in critical compartments of the central nervous system that cannot be collected in clinical studies. To illustrate the translational value of the model, we report the penetration of linezolid from plasma into the CSF, meninges, anatomically distinct brain areas, cervical spine, and lumbar spine. Across animals, we measured the bacterial burden concomitant with neurological deterioration, offering a useful readout for drug efficacy studies. The model thus forms the basis for building a preclinical platform to identify improved regimens and inform clinical trial design.

A preliminary evaluation of targeted nanopore sequencing technology for the detection of Mycobacterium tuberculosis in bronchoalveolar lavage fluid specimens.

To evaluate the efficacy of targeted nanopore sequencing technology for the detection of Mycobacterium tuberculosis(M.tb.) in bronchoalveolar lavage fluid(BALF) specimens. A prospective study was used to select 58 patients with suspected pulmonary tuberculosis(PTB) at Henan Chest Hospital from January to October 2022 for bronchoscopy, and BALF specimens were subjected to acid-fast bacilli(AFB) smear, Mycobacterium tuberculosis MGIT960 liquid culture, Gene Xpert MTB/RIF (Xpert MTB/RIF) and targeted nanopore sequencing (TNS) for the detection of M.tb., comparing the differences in the positive rates of the four methods for the detection of patients with different classifications. Among 58 patients with suspected pulmonary tuberculosis, there were 48 patients with a final diagnosis of pulmonary tuberculosis. Using the clinical composite diagnosis as the reference gold standard, the sensitivity of AFB smear were 27.1% (95% CI: 15.3-41.8); for M.tb culture were 39.6% (95% CI: 25.8-54.7); for Xpert MTB/RIF were 56.2% (95% CI: 41.2-70.5); for TNS were 89.6% (95% CI: 77.3-96.5). Using BALF specimens Xpert MTB/RIF and/or M.tb. culture as the reference standard, TNS showed 100% (30/30) sensitivity. The sensitivity of NGS for pulmonary tuberculosis diagnosis was significantly higher than Xpert MTB/RIF, M.tb. culture, and AFB smear. Besides, P values of <0.05 were considered statistically significant. Using a clinical composite reference standard as a reference gold standard, TNS has the highest sensitivity and consistency with clinical diagnosis, and can rapidly and efficiently detect PTB in BALF specimens, which can aid to improve the early diagnosis of suspected tuberculosis patients.

Primary Parotid Tuberculosis in a Toddler

Tuberculosis (TB) of the parotid gland is a rare disease and occurs less frequently in children. Re-emergence is seen amongst immunocompromised individuals whose diagnosis may be overlooked, leading to unnecessary surgery. Diagnosis is challenging in the absence of systemic constitutional symptoms and depends mainly on the treating physician having a strong suspicion. We report a rare extrapulmonary manifestation of TB involving the parotid gland in an otherwise immunocompetent child. A 2-year-old girl presented with a mass in the right parotid region that had been present for 3 months. A similar swelling was treated with an antibiotic 3 months prior, but it recurred. The mass was painful, firm, erythematous, and located in the infra-auricular region. Symptoms persisted after 2 courses of antibiotics, after which ultrasonography was performed and the intra-parotid collection was aspirated, which was positive for acid-fast bacilli (AFB). The patient was placed on anti-TB treatments. Although uncommon, TB should be considered in patients with a solitary mass in the parotid gland to avoid unnecessary surgery.

Nocardia farcinica abortion in a goat.

A female goat fetus was received by the Colorado State University-Veterinary Diagnostic Laboratory following an isolated abortion of twins by a reportedly healthy doe. Postmortem examination did not reveal any gross abnormalities. Histologic evaluation revealed pyogranulomatous and necrotizing bronchopneumonia with intracellular and extracellular gram-positive and non-acid-fast filamentous bacilli. Aerobic culture of the stomach contents and pooled lung and liver tissue yielded light growth of Nocardia sp., which was identified by MALDI-TOF MS and 16s rDNA sequencing as Nocardia farcinica.

Catheter-related bloodstream infection caused by Tsukamurella tyrosinosolvens identified by secA1sequencing in an immunocompromised child: a case report

BackgroundTsukamurella spp. are obligate aerobic, gram-positive, non-motile, and slightly acid-fast bacilli belonging to the Actinomycetes family. They share many characteristics with Nocardia, Rhodococcus, Gordonia, and the rapidly growing Mycobacterium species. Therefore, standard testing may misidentify Tsukamurella spp. as another species. Accurate and rapid diagnosis is critical for proper infection management, but identification of this bacterium is difficult in the standard laboratory setting.Case presentationA bloodstream infection caused by a gram-positive bacterium and related to a central venous catheter was identified in an immunocompromised 2-year-old girl. Tsukamurella tyrosinosolvens was identified by modified secA1 sequencing. Antibiotic treatment and removal of the central venous catheter resolved the infection. Inappropriate management of the catheter during an overnight stay outside of the hospital was considered as a possible source of infection.ConclusionsSecA1 sequencing may be a useful diagnostic tool in the identification of T. tyrosinosolvens. Providing proper central venous catheter care instructions to patients, their families, and medical staff is important for infection prevention.