Tuberculosis (TB) remains one of the top infectious killers worldwide, with India bearing the highest burden, accounting for 27% of global cases (WHO, 2020). Pulmonary tuberculosis (PTB) is the most common form, affecting the lungs and leading to severe respiratory complications if untreated. Despite advancements in diagnostics and treatment, challenges such as drug resistance, poor adherence, and adverse drug reactions persist (Chakraborty et al., 2019).

The Revised National Tuberculosis Control Program (RNTCP) in India has implemented Directly Observed Treatment Short-course (DOTS) to ensure treatment compliance. However, variations in treatment outcomes due to socioeconomic factors, comorbidities, and drug resistance patterns necessitate further research (Sharma et al., 2018). Studies in urban settings like Bangalore are crucial due to high population density and increased transmission risks.

Previous studies have highlighted the efficacy of first-line ATT, including isoniazid, rifampicin, pyrazinamide, and ethambutol (HRZE), in achieving sputum conversion (Gupta et al., 2020). However, adverse effects such as hepatotoxicity and gastrointestinal disturbances remain major concerns, leading to treatment discontinuation in some cases (Kumar et al., 2019). Understanding these factors can optimize treatment protocols and improve patient outcomes.

This study aims to evaluate the effectiveness of ATT in a tertiary care hospital in Bangalore, focusing on treatment response, sputum conversion rates, and adverse drug reactions. The findings will contribute to refining TB management strategies in high-burden settings.

OBJECTIVE

The primary objective of this study was to assess the clinical and microbiological outcomes of PTB patients undergoing standardized ATT in a tertiary care hospital in Bangalore. Parameters included sputum conversion rates, treatment adherence, and incidence of adverse drug reactions.

Additionally, the study aimed to identify factors influencing treatment outcomes, such as age, gender, comorbidities, and drug resistance patterns. By analyzing these variables, we sought to provide insights into optimizing TB management in similar healthcare settings.

This study adopted a structured and methodical approach to evaluate the clinical outcomes of pulmonary tuberculosis (PTB) patients undergoing standardized anti-tubercular therapy (ATT) in a tertiary care setting. The methodology was designed to ensure accurate documentation of patient demographics, clinical progress, adherence levels, and drug-related adverse events over the treatment period. Emphasis was placed on real-world clinical conditions, enabling the findings to reflect the practical challenges and successes encountered in routine TB management. All procedures were conducted in alignment with national TB control protocols, ensuring both scientific rigor and ethical compliance.

Study Design and Setting:

A hospital-based, prospective observational study was carried out at a tertiary care center in Bangalore over four months, from December 2020 to March 2021. The study was approved by the Institutional Ethics Committee. Written informed consent was obtained from all participants before enrollment.

Participants and Sampling:

A total of 200 patients were recruited through purposive sampling from the outpatient and inpatient departments. All participants had newly diagnosed, microbiologically confirmed PTB.

Inclusion Criteria:

• Age ≥ 18 years
• Positive sputum smear or culture for Mycobacterium tuberculosis
• Willingness to provide informed consent and attend regular follow-up

Exclusion Criteria:

• Patients with extrapulmonary TB
• Pregnant or lactating women
• Patients with chronic liver disease or renal failure
• Previously treated TB cases or those on second-line drugs

Treatment Protocol:

Patients were treated with first-line ATT under the national guidelines: isoniazid (H), rifampicin (R), pyrazinamide (Z), and ethambutol (E) for the intensive phase (2 months), followed by a continuation phase with isoniazid and rifampicin for 4 months. DOTS (Directly Observed Treatment Short-course) strategy was implemented.

Data Collection Procedure:

Baseline demographics, clinical features, chest radiographs, sputum smear microscopy, and liver function tests were recorded at enrollment. Patients were evaluated monthly for clinical improvement, adverse drug reactions, and sputum status. Adherence was tracked via pill counts and DOTS records.

Outcome Measures:

• Primary: Sputum conversion at 2 months
• Secondary: Treatment success rate, adverse drug reactions, default rate

Statistical Analysis:

Data were analyzed using SPSS v25. Descriptive statistics were used to summarize data. Chi-square tests assessed associations between categorical variables. Logistic regression identified predictors of treatment success. A p-value <0.05 was considered statistically significant.

Demographic and Clinical Characteristics

The study included 200 PTB patients, with a mean age of 42.5 ± 12.3 years. Males constituted 62% of the cohort. Comorbidities such as diabetes (18%) and hypertension (14%) were observed.

Treatment Outcomes

After two months of ATT, 78% achieved sputum conversion. Treatment success was observed in 85% of patients, while 8% defaulted, and 7% showed drug resistance.

Adverse Drug Reactions

Hepatotoxicity (12%), gastrointestinal disturbances (6%), and skin rashes (4%) were the most common adverse effects.

Table 1: Demographic Distribution of Study Participants

Table 2: Treatment Outcomes

Table 3: Adverse Drug Reactions (ADR)

Table 4: Factors Associated with Treatment Success

Table 5: Comparison with Previous Studies

DISCUSSION

The findings of our study reaffirm the efficacy of standardized ATT in treating pulmonary tuberculosis. With a sputum conversion rate of 78% and a treatment success rate of 85%, our outcomes align closely with national averages and other urban tertiary care studies (Gupta et al., 2020; Singh et al., 2020).

However, the observed 7% drug resistance rate, although consistent with earlier reports (Selvakumar et al., 2016), is concerning and underscores the need for early detection of multidrug-resistant TB (MDR-TB). Prompt referral for GeneXpert testing and drug susceptibility testing (DST) should be prioritized.

The incidence of hepatotoxicity (12%) mirrors previously reported figures (Jain et al., 2016), reinforcing the importance of baseline liver function assessments and vigilant monitoring throughout treatment. Adverse reactions significantly impacted adherence, particularly in older adults and those with comorbidities.

Treatment defaulters (8%) were predominantly from socioeconomically disadvantaged backgrounds, highlighting the intersection of poverty, awareness, and health-seeking behavior in TB control (Satyanarayana et al., 2015). Strengthening counseling and support systems, possibly through community health workers and nutritional incentives, may mitigate this risk.

Our study also found better outcomes among younger patients and those without comorbid conditions, suggesting that tailored interventions for high-risk groups are necessary. The integration of psychological support, nutritional guidance, and digital adherence technologies could further bolster treatment outcomes.

LIMITATIONS OF THE STUDY

The study was limited by its short duration and single-center design. Long-term follow-up was not feasible, and some patients were lost to follow-up. Future multi-center studies with extended observation periods are recommended.

ACKNOWLEDGMENT

We thank the hospital staff and patients for their cooperation. This study was supported by the Department of Pulmonary Medicine.

This study demonstrates that standardized ATT, when implemented effectively under the DOTS strategy, can yield favorable clinical and microbiological outcomes in pulmonary TB patients. High sputum conversion and treatment success rates underscore the protocol’s efficacy.

Nonetheless, the prevalence of adverse drug reactions, drug resistance, and defaulting underscores the need for enhanced patient-centric care. Future strategies must prioritize early detection of resistance, robust pharmacovigilance, and interventions addressing social determinants of health. Personalized medicine, community engagement, and integrated care pathways could significantly enhance India’s TB control efforts.

Comprehensive and sustained investment in TB research, infrastructure, and patient support will be critical to realizing the country's TB elimination goals by 2025.

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