Application of serial tests for Mycobacterium tuberculosis detection to active lung tuberculosis cases in Indonesia

Novel automated AIMLAM for diagnosis of Mycobacterium tuberculosis

Aim: A rapid and precise diagnostic method is crucial for timely intervention and management of tuberculosis. The present study compared the diagnostic accuracy of a novel lipoarabinomannan (LAM) antigen test, AIMLAM, for tuberculosis in urine samples. Methodology: The study subjected 106 TB suspects to smear microscopy, MGIT, GeneXpert and AIMLAM. Results: Among 106, smear microscopy identified 36 as positive (33%) (sensitivity; 70.93%, 95% CI (60.14-80.22%), while MGIT showed 38 positive (36.8%). GeneXpert detected 59 positives (sensitivity; 96.83, 95% CI (89.00-99.61%)). AIMLAM declared 61 as positive (57.5%) (sensitivity; 100.00, 95% CI (94.13-100.00%) and 45 as negative (42.5%). Conclusion: Overall, AIMLAM demonstrated better diagnostic accuracy than GeneXpert Assay, smear microscopy and MGIT liquid culture in urine samples.

Mycobacterium tuberculosis - atpE gene profile of bedaquiline-treated pulmonary tuberculosis patients at the referral hospital Dr. Soetomo, Indonesia

Background

The atpE gene is a target for bedaquiline (Bdq)-activating drug action and mutations in the gene are fixed to cause resistance. However, changes in the amino acid of ATPase have been little reported from a clinical setting since it was first used in 2015 in Indonesia. This study aims to observe the sequence of nucleotide and amino acid from rifampicin-resistant (RR) pulmonary tuberculosis (TB) patients, both new and relapse cases treated with Bdq.

Methods

This is an observational descriptive study performed in the referral hospital Dr Soetomo, Indonesia, at August 2022-November 2022. We performed Sanger sequencing and comparison of the atpE gene from the patient's sputum from August to November 2022 to wild-type Mycobacterium tuberculosis H37Rv and species of mycobacteria using BioEdit version 7.2 and BLAST NCBI software. We also conducted an epidemiological study on patients' characteristics. This study uses a descriptive statistic to show the percentage of data.

Results

The total of 12 M. tuberculosis isolates showed that the atpE gene sequence was 100% similar to the wild-type M. tuberculosis H37Rv. No single-nucleotide polymorphisms or mutations were found, and no change in the amino acid structure at position 28 (Asp), 61 (Glu), 63 (Ala), and 66 (Ile). The percentage identity of atpE to M. tuberculosis H37Rv and M. tuberculosis complex was 99%-100%, while the similarity with the other mycobacteria species other than TB (Mycobacterium avium complex, Mycobacterium abscessus, and Mycobacterium lepraemurium) was 88%-91%.

Conclusions

This study revealed M. tuberculosis -atpE gene sequence profile of RR-TB patients had no mutations, as the specific gene region, and no change in the amino acid structure. Therefore, Bdq can be continually trusted as an effective anti-tubercular drug in RR-TB patients.

Differences in CT imaging signs between patients with tuberculosis and those with tuberculosis and concurrent lung cancer

OBJECTIVE

The purpose of this study was to compare the differences in imaging features between patients with pulmonary tuberculosis (TB) alone and patients with TB complicated with lung cancer (LCA) as well as to investigate the diagnostic value of CT in these two groups.

METHODS

In this retrospective study, 110 patients with confirmed TB admitted to the Second Affiliated Hospital of Hainan Medical University from March 2020 to April 2021 were collected and divided into TB+LCA group (50 cases, diagnosed with TB complicated with lung cancer) and TB group (60 cases, diagnosed with TB alone) according to actual diagnosis. The CT results of both groups were analyzed by the same group of physicians in a double-blind manner. The diagnostic value of CT for TB alone and TB complicated with lung cancer was calculated. The differences in CT imaging characteristics between the two groups were investigated. The differences in the structural characteristics of para-cancerous tissue between the two groups were analyzed.

RESULTS

The diagnostic accuracy of CT was 91.67% in TB patients (55/60) and 92.00% in TB+LCA patients (46/50) without significant difference (X² =0.004, P=0.949). The detection rate of spiculation, lobulation and cavitation in TB+LCA group was significantly higher than that in TB group (P<0.05), and the distribution, size and wall thickness of cavitation varied significantly between the two groups (P<0.05). Patients in TB group had higher percentage of mediastinal lymph node calcification, peripheral satellite lesion, and mediastinal lymph node enlargement around the TB lesions compared with those in TB+LCA group (P<0.05).

CONCLUSION

CT has certain application value in differentiating TB alone from TB complicated with lung cancer, and there are many similarities in the imaging features of the two conditions. CT can be considered as a preliminary means of differential diagnosis of TB complicated with lung cancer, which is helpful to the primary screening diagnosis of lung cancer.

A case of paradoxical reaction after treatment of generalized tuberculous lymphadenopathy in a peritoneal dialysis patient

Paradoxical reaction (also known as Jarisch–Herxheimer reaction) is a self-limited response to endotoxin released from dead bacteria after starting treatment and is characterized by constitutional symptoms such as fever, headache, dizziness and exacerbation of cutaneous lesions. We report a rare case of a 55-year-old gentleman, on peritoneal dialysis, who developed fever, dizziness and cloudy dialysate after starting anti-tuberculous treatment for disseminated tuberculous lymphadenitis. He was started on antibiotics for suspected peritoneal dialysis peritonitis and anti-tuberculosis treatment was continued. However, all his cultures turned out negative including peritoneal 16S ribosomal RNA. The diagnosis of paradoxical worsening following anti-tuberculosis treatment was made. His peritoneal dialysis was continued and he made full recovery after 8 months of therapy. This case highlights the fact that in a peritoneal dialysis patient, paradoxical reaction can present as cloudy dialysate with raised infective markers.

The Diagnostic Deceiver: Radiological Pictorial Review of Tuberculosis

Tuberculosis (TB) is a bacterial infection with Mycobacterium tuberculosis; it is a public health problem worldwide and one of the leading causes of mortality. Since December 2019, the COVID-19 pandemic has created unprecedented health challenges and disrupted the TB health services, especially in high-burden countries with ever-increasing prevalence. Extrapulmonary and even pulmonary TB are an important cause of nonspecific clinical and radiological manifestations and can masquerade as any benign or malignant medical case, thus causing disastrous conditions and diagnostic dilemmas. Clinical manifestations and routine laboratory tests have limitations in directing physicians to diagnose TB. Medical-imaging examinations play an essential role in detecting tissue abnormalities and early suspecting diagnosis of TB in different organs. Radiologists and physicians should be familiar with and aware of the radiological manifestations of TB to contribute to the early suspicion and diagnosis of TB. The purpose of this article is to illustrate the common radiologic patterns of pulmonary and extrapulmonary TB. This article will be beneficial for radiologists, medical students, chest physicians, and infectious-disease doctors who are interested in the diagnosis of TB.