Assessment of burden of drug-resistant tuberculosis at a tertiary care centre in northern India: a prospective single centre cohort study

Insights into changing patterns of extrapulmonary tuberculosis in North India

PURPOSE

Tuberculosis is one of the dreadful infections and India contributes to substantial burden of TB cases globally. Though majority of cases are pulmonary, extra-pulmonary tuberculosis (EPTB) share significant burden, more in HIV-positive persons. Despite the striking burden, very few studies have been conducted in India and present study was undertaken to determine trends of EPTB at our tertiary care centre.

METHODS

This was a retrospective study conducted over a period of 4 years 3 months. Diagnosis of EPTB was based on suspected clinical features, with positive micobiological evidence with cartridge based nucleic acid amplification test (CBNAAT) with/without microscopy.

RESULTS

A total of 10,560 samples (pulmonary and extra-pulmonary) were received during the study period, of which 3972 were extrapulmonary. Of these, a total of 18% were noted to be positive for EPTB. Trend of positivity revealed highest burden in 2018 and a decline was noted over the years, however, rise in cases was noted in 2022. Pleural, meningitis, musculoskeletal, peritoneal and pericardial TB was more common in males, while lymphadenitis was more common in females (p value: <0.0001). Pleural TB (31%) was the most common presentation, followed by lymphadenitis. A gradual decline in lymphadenitis was noted with significantly increasing trend only for musculoskeletal TB. Rifampicin resistance was detected in 7.45% of positive samples, of which the maximum rate of resistance was noted in lymph node aspirates (11.11%), followed by musculoskeletal and pleural samples.

CONCLUSION

The present study showed a gradual decline in positivity of EPTB cases over the years. Younger productive age group with more propensity to transmit infection was the most commonly affected, with pleural TB as the most common presentation. Rare presentations of EPTB also contributed major share. Higher rates of resistance underline requisite to strengthen ongoing programs, to achieve the End TB strategy by 2025.

A rare case of isoniazid mono-resistant tuberculosis presenting as cardiac tamponade along with an anterior mediastinal mass in a 15-year-old immunocompetent patient

ABSTRACT

A 15-year-old boy presented with a sudden onset of breathlessness for 7 days, gradual loss of weight of 17.6 lbs over the last month and progressive hoarseness of voice for 7 months. The contrast-enhanced computed tomography (CECT) scan revealed a heterogeneously enhancing lesion in the anterior mediastinum with multiple discrete lymph nodes in the cervical and mediastinal locations. The GeneXpert MTB/RIF assay performed on the CT-guided biopsy of the mass was negative, but the culture for Mycobacterium tuberculosis was positive at 7 weeks of incubation. There was a suboptimal radiological response after 6 months of treatment. First-line drug susceptibility testing (DST) performed by line probe assay (LPA) on the positive culture detected high-level resistance to isoniazid. The treatment was modified as per DST results to which the patient responded well.

Clinical and Radiological End Points to Stop Anti-Tubercular Treatment in Central Nervous System Tuberculoma and Predictors of Poor Outcome: A Retrospective Study

The clinical and radiological end points to stop anti-tubercular treatment in central nervous system (CNS) tuberculoma are not known. This retrospective study was done to determine end points to stop anti-tubercular treatment and find the predictors of poor outcome in patients with CNS tuberculoma. Patients who were admitted with a diagnosis of brain/spine tuberculoma between January 2015 and December 2019 and who completed a minimum of 1-year follow-up were enrolled. Clinical and radiological end points to stop anti-tubercular treatment and predictors of death and poor outcome (modified Rankin scale > 2) were analyzed. One hundred and eight patients (male-to-female ratio, 47 [43.5%]:61 [56.5%]; brain tuberculoma, 102; spinal cord tuberculoma, 14; brain and spinal cord tuberculoma, 8) were included in the study. Median duration of anti-tubercular treatment was 24 months. Radiological resolution of tuberculoma (resolution of gadolinium-enhancing lesion, gliosis, calcification, cord atrophy, or syrinx formation) and radiological halt (no increase in size/number of tuberculoma on magnetic resonance imaging scans done 6 months apart) were used as end points to stop anti-tubercular treatment in 69 and 7 patients, respectively. Seven patients stopped their treatment by themselves, and 25 patients died. Altered sensorium, motor weakness, infarcts, hydrocephalus, and constitutional symptoms of tuberculous meningitis were predictors of poor outcome or death in CNS tuberculoma patients. Radiological resolution or radiological halt of brain/spinal cord tuberculoma was a reasonable end point to stop anti-tubercular treatment. However, this may require 24 months or more of anti-tubercular treatment. Associated tuberculous meningitis and its complications portend a poor prognosis.

Acid fast bacillus smear, mycobacterial culture and Xpert MTB/RIF assay for the diagnosis of tuberculous peritonitis in patients with and without end stage renal failure

Introduction.

Diagnosis of tuberculous peritonitis (TBP) requires a high index of suspicion.

Hypothesis /gap statement.

Information about the diagnostic features of TBP among patients with end-stage renal failure (ESRF) from India is limited.

Aim.

To assess the utility of the Gene Xpert MTB/RIF assay in the diagnosis of TBP in patients with end-stage renal failure (ESRF), compared with those without ESRF.

Methodology.

This prospective observational single centre cohort study was performed at a tertiary care centre in Northern India. Ascitic fluid and/or whole continuous ambulatory peritoneal dialysis (CAPD) bag with effluent from 300 clinically suspected cases of TBP were included in the study. Diagnosis was based on detection of Mycobacteria on smear, Xpert MTB/RIF assay and/or culture. Cell counting was done in a Neubauer chamber. Cell predominance was seen by Giemsa stain. Line probe assay (LPA) for drug susceptibility testing was performed on all positive cultures.

Results.

TBP was diagnosed in 168 cases. Diabetes mellitus was a significant risk factor for developing TBP in patients with ESRF (P value<0.01). Lymphocytic predominance was seen in 21 patients without ESRF (P value 0.033) while majority of the patients in both groups had neutrophils in their ascitic and peritoneal fluids (138/168; P value 0.033). We recovered 15 cases of laboratory diagnosed TBP (11 without ESRF and four with ESRF). Microscopy was positive in two cases while ten isolates were recovered on culture. The Xpert MTB/RIF assay was positive in seven ascitic fluid samples out of which three were rifampicin resistant. All these were patients without renal failure (P value 0.010). Eight culture positive samples tested by the line probe assay did not detect any resistance to either rifampicin or isoniazid.

Conclusion.

The GeneXpert MTB/RIF assay has a limited value in the diagnosis of TBP in patients with ESRF.

Tuberculosis challenges: Resistance, co-infection, diagnosis, and treatment

Early diagnosis of tuberculosis (TB), followed by effective treatment, is the cornerstone of global TB control efforts. An estimated 3 million cases of TB remain undetected each year. Early detection and effective management of TB can prevent severe disease and reduce mortality and transmission. Intrinsic and acquired drug resistance of Mycobacterium tuberculosis (MTB) severely restricted the anti-TB therapeutic options, and public health policies are required to preserve the new medications to treat TB. In addition, TB and HIV frequently accelerate the progression of each other, and one disease can enhance the other effect. Overall, TB-HIV co-infections show an adverse bidirectional interaction. For HIV-infected patients, the risk of developing TB disease is approximately 22 times higher than for persons with a protective immune response. Analysis of the current TB challenges is critical to meet the goals of the end TB strategy and can go a long way in eradicating the disease. It provides opportunities for global TB control and demonstrates the efforts required to accelerate eliminating TB. This review will discuss the main challenges of the TB era, including resistance, co-infection, diagnosis, and treatment.