Prevalence of pre-extensively drug-resistant tuberculosis (Pre XDR-TB) and extensively drug-resistant tuberculosis (XDR-TB) among extra pulmonary (EP) multidrug resistant tuberculosis (MDR-TB) at a tertiary care center in Mumbai in pre Bedaquiline (BDQ) era

Abstract

Background: Drug-resistant tuberculosis (DR-TB) is the most exigent and calamitous challenge encountered in treatment of TB. Extra pulmonary (EP) DR-TB poses a complex diagnostic and therapeutic challenge owing to myriad of presentations and paucibacillary nature. Data available on this subset is limited. We studied the prevalence of EPDR-TB cases among the total DR-TB cases visiting our Programmatic management of Drug-Resistant TB (PMDT) site. We also studied the demographic and microbiological profile of these cases and analyzed the prevalence of pre-extensively drug-resistant TB (pre XDR-TB) and extensively drug-resistant TB (XDR-TB) among patients of EPDR-TB in pre Bdq era. Results: Of the 1086 DR-TB patients, 64 (5.89%) were cases of EPDR-TB. Seven out of 64 (10.93%) were primary EPDR-TB. The site wise distribution of cases was 34 (53.125%) lymph node DR-TB, 18 (28.125%) pleural DR-TB, 9 (14.0625%) spinal DR-TB/paraspinal abscess/psoas abscess, 1 case (1.5625%) each of abdominal DR-TB, sternal and gluteal abscess. On the basis of the second-line drug susceptibility testing (DST), patients were grouped into: (1) multidrug-resistant TB (MDR-TB), (2) MDR-TB with fluoroquinolone (FQ) resistance {pre XDR XDR-TB (FQ)}, (3) MDR-TB with second-line injectable (SLI) resistance {pre XDR XDR-TB (SLI)}, (4) XDR-TB. Of the 64 patients, 43 (67.185%) had MDR-TB, 19 (29.687%) had preXDR-TB (FQ), none had preXDR-TB (SLI) and 2 (3.125%) had XDR-TB. Gastro esophageal reflux disease (GERD) was the most common comorbidity seen in 26 (40.6%) patients, followed by anemia in 5 (7.8%), psychiatry problems 5 (7.8%), hypertension in 3 (4.6%), renal disorders in 2 (3.1%) while thyroid disorder, HIV and thalassemia in 1 each (1.5%). Conclusion: EPDR-TB forms a small but significant proportion of total DR-TB. Lymph node DR-TB is its most common subclass. Our study emphasises the momentousness and essentiality of baseline DST to FQ and SLI in patients of DR-TB. This enables an appropriate modification of therapy at baseline itself to better the treatment outcomes. We observed a strikingly high proportion of preXDR-TB (FQ) in our study group.

Investigating the Mutations in atpE and Rv0678 Genes in Mycobacterium Tuberculosis Clinical Isolates

“…In Ecuador, among 21 isolates investigated in 2023, 15 (71.4%) were MDR, and 2 (9.5%) were XDR, rates that almost match our findings [23]. In a 2023 study in India, of 64 isolates, 43 (67.1%) were identified as MDR and 2 (3.1%) as XDR [24].…”

Drug-resistant Mycobacterium tuberculosis among Nepalese patients at a tuberculosis referral center

“…It Is interesting to note that a higher number of pre-XDR-TB and XDR-TB cases were diagnosed in the adult (16-59 years) age group. Independent studies in Bangladesh and India also reported an increased prevalence of pre-XDR-TB among the 21-30 and 18-25 age groups, respectively [13,18]. Moreover, the prevalence of FLQ and SLID resistance TB was notably higher in individuals aged 16-59, especially among males compared to females.…”

“…pre-XDR-TB and 8% for XDR-TB [17]. In contrast, previous studies have shown divergent rates, with India reporting a pre-XDR-TB rate of 56%, China at 34%, and Bangladesh at 16% [13,18,19]. Similarly, multi-center studies of MDR-TB patients across eight nations and Poland found a comparable rate of XDR-TB, with 6.7% and 6.4%, respectively [20,21].…”