Trends in nontuberculous mycobacterial disease in hospitalized subjects in Spain (1997-2010) according to HIV infection

Diagnosis of extrapulmonary tuberculosis by ultrasound-guided biopsy: A retrospective comparison study

Objective

To compare the diagnostic performance of laboratory assays on the ultrasound-guided core needle biopsy samples for diagnosis of extra-pulmonary tuberculosis (EPTB) in HIV-positive and HIV-negative patients.

Methods

A total of 217 patients suspected to have EPTB underwent lesion biopsy from 2017 to 2020. Results of laboratory tests on the biopsy and non-biopsy samples were collected with clinical data for retrospective analysis of test utility. The calculated diagnostic accuracy of the tests was stratified according to the specimen types and HIV status.

Results

The cohort contained 118 patients with a final positive diagnosis of extrapulmonary tuberculosis (EPTB group, 54.4%) and 99 finally diagnosed as without TB (non-EPTB group, 45.6%). The risk factor for EPTB was HIV co-infection (OR 2.22, 95% CI 1.17-4.28, p = 0.014). In biopsy samples, GeneXpert (Xpert) showed higher sensitivity (96.6% [91.6-98.7], p < 0.0001) than culture (56.1% [47.0-64.9]). Regardless of HIV status, Xpert had the highest sensitivity (>95%) and specificity (nearly 100%) of any methods. In non-biopsy samples, only T-SPOT.TB (T-SPOT) showed higher sensitivity than culture (90.9% [62.3-99.5] vs 35.3% [17.3-58.7], p = 0.0037). Furthermore, the sensitivities of Xpert were lower in non-biopsy samples (60.0% [23.1-92.9], p = 0.022) than in biopsy samples (100% [86.7-100]). Even in smear-negative biopsy samples, Xpert still had higher sensitivity than culture and retained high specificity (100% [95.7-100]).

Conclusion

Superior performance of Xpert in diagnosing EPTB was observed regardless of HIV status and specimen types. Nevertheless, the biopsy samples still substantially facilitated the accurate diagnosis of extrapulmonary tuberculosis.

Nontuberculous mycobacteria isolation from sputum specimens: A retrospective analysis of 1061 cases

Background

In recent years, with the development of laboratory methods, the frequency of nontuberculosis mycobacteria (NTM) infections has increased. The primary aim of this study was to evaluate the clinical significance of therapeutic drug monitoring (TDM) growths in respiratory samples, and the secondary aim was to evaluate the treatment regimens and treatment outcomes of treatment for TDM disease.

Methods

This study was a retrospective cohort study. Persons with NTM growth in respiratory samples admitted to the reference hospital between 2009 and 2020 were included in this study. Samples detected as NTM by the immunochromatographic rapid diagnostic test, those requested by the clinicians, species were determined by the hsp65PCRREA method. The subjects were classified into 3 groups: patients with NTM infection who received treatment (135, 12.7%), those followed up without treatment (690, 65.1%), and a last group of patients with Mycobacterium tuberculosis (TB) complex strains were isolated and received TB treatment (236, 22.2%). Initiating NTM treatment was decided in accordance with the American Thoracic Society recommendations.

Results

The mean ± standard deviation age of patients was 53.8 ± 16.5 years, and 749 (70.6%) were male. In total, 278 (26.2%) out of 1061 cases had identified, and the most frequent species were MAC (81; Mycobacterium avium: 39, Mycobacterium intracellulare: 39, and MAC: 3), Mycobacterium abscessus (67), Mycobacterium kansasii (48), Mycobacterium fortuitum (23), Mycobacterium chelonae (12), Mycobacterium gordonae (11), and Mycobacterium szulgai (11). In the NTM treatment group, 116 (85.9%) of 135 patients had multiple culture positivity. Previous TB treatment history had 51 (37.8%) of 135 patients, respiratory comorbidities were evident in 37 (27.4%) of 135 patients. Thorax computed tomography imaging in 84 patients revealed nodule 38 (45.2%), consolidation 46 (54.8%), cavity 52 (61.9%), and bronchiectasis 27 (32.1%). Treatment results in the NTM treatment group were as follows: ongoing treatment 14 (10.4%), cure 64 (47.4%), default 33 (24.4%), exitus 19 (14.1%), recurrence 3 (2.2%), and refractory disease 2 (1.5%).

Conclusion

This is a large case series evaluating the clinical significance of NTM growths and NTM treatment in Turkey. The clinical significance of NTM growth in respiratory samples is low. Treatment success rates of NTM patients who are treated are low. Treatment defaults and mortality rates are high. New drugs and new regimens are needed.

Clinical characteristics of nontuberculous mycobacterial disease in people living with HIV/AIDS in South Korea: A multi-center, retrospective study

With the introduction of combination antiretroviral therapy (cART), the prevalence of human immunodeficiency virus (HIV)-associated nontuberculous mycobacteria (NTM) disease has declined. However, NTM diseases still occur in people living with HIV/acquired immunodeficiency syndrome (AIDS) (PLWHA). We analysed the clinical and microbiological features of NTM diseases in PLWHA in South Korea. PLWHA who were diagnosed with NTM diseases between January 2000 and March 2021 were retrospectively enrolled from five different hospitals in South Korea. Data on baseline demographics, HIV status, CD4+ T cell counts, viral load, past and current cART regimens, isolated NTM species, results of antimicrobial susceptibility tests, treatment regimens, and outcomes were collected by reviewing medical records. A total of 34 cases of NTM in PLWHA were included. Pulmonary and extrapulmonary NTM diseases accounted for 58.8% (n = 20) and 41.2% (n = 14), respectively. The lymph node was the most common site of extrapulmonary NTM disease (64.3%). The age at the time of NTM disease diagnosis was younger in the extrapulmonary NTM group than in the pulmonary NTM group (37.0 vs. 49.0 years). Mean CD4+ T cell counts at the time of NTM disease diagnosis was 186.6 cells/μL (range: 1–1394). Nine patients (26.5%) had fully suppressed viral loads at the time of NTM disease diagnosis. Mycobacterium avium complex (MAC) was the most common species found, followed by M. intracellulare and M. kansasii. MAC isolates were all susceptible to clarithromycin, but the rates of non-susceptibility to moxifloxacin, linezolid, ethambutol, and rifampin were 75%, 37.5%, 12.5%, and 12.5%, respectively. The average duration of treatment was 17 months and the mortality rate was 8.8%. NTM diseases may occur in PLWHA, even with completely suppressed viral loads. The identified clinical features of NTM diseases are essential for its clinical management in South Korea.

Mycobacterium avium complex infection in patients with human immunodeficiency virus: A systematic review and meta-analysis

BACKGROUND

Mycobacterium avium-intracellulare complex (MAC) is one of the leading causes of death among people living with human immunodeficiency virus (HIV). The current study was aimed to determine the frequency of MAC infection in patients infected with HIV.

METHODS

Embase, PubMed, and Web of Science were searched for relevant studies. All statistical analyses were performed by STATA version 14.

RESULTS

From 6,627 retrieved articles, 23 were included in the final analysis. A total of 18,463 patients with HIV were included in the analysis. The frequency of MAC infection in patients with HIV was found to be 10.6% (95% confidence interval, 6.9-14.2).

CONCLUSION

The relatively large fractions of HIV-infected patients were coinfected with MAC, which may poses significant public health problems. Continued progress in the development of rapid diagnostic methods and preventive therapy for MAC should lead to further improvements in survival and quality of life in patients with HIV.

Molecular Identification of Nontuberculous Mycobacteria in Humans in Zimbabwe Using 16S Ribosequencing

Background:

Several nontuberculous mycobacteria (NTM) were previously isolated from diverse environments such as water, soil, sewage, food and animals. Some of these NTM are now known to be opportunistic pathogens of humans.

Objective:

The main purpose of the study was to identify NTM isolates stored at the National Microbiology Reference Laboratory (NMRL) and were previously isolated from humans during a national tuberculosis (TB) survey.

Methods:

Pure NTM cultures already isolated from human sputum samples during the national TB survey were retrieved from the NMRL and used for this study. DNA was extracted from the samples and 16S ribosomal RNA gene amplified by polymerase chain reaction. The amplicons were sequenced and bioinformatics tools were used to identify the NTM species.

Results:

Out of total of 963 NTM isolates stored at the NMRL, 81 were retrieved for speciation. Forty isolates (49.4%) were found to belong to Mycobacterium avium-intracellulare complex (MAC) species. The other 41 isolates (50.6%) were identified as M. lentiflavum (6.2%), M. terrae complex (4.9%), M. paraense (4.9%), M. kansasii (3.7%), M. moriokaense (3.7%), M. asiaticum (2.5%), M. novocastrense (2.5%), M. brasiliensis (2.5%), M. elephantis (2.5%), M. paraffinicum (1.2%), M. bohemicum (1.2%), M. manitobense (1.2%), M. intermedium (1.2%), M. tuberculosis complex (1.2%), M. parakoreense (1.2%), M. florentinum (1.2%), M. litorale (1.2%), M. fluoranthenivorans (1.2%), M. sherrisii (1.2%), M. fortuitum (1.2%) and M septicum (1.2%). Two isolates (2.5%) could not be identified, but were closely related to M. montefiorense and M. phlei respectively. Interestingly, the MAC species were the commonest NTM during the survey.

Conclusion:

The study emphasizes the importance of identifying species of NTM in Zimbabwe. Future studies need to ascertain their true diversity and clinical relevance.