Authors: 

Zainab Akhtar¹, 

Waqas Hussain²

¹Hyderabad Chest Clinic | ²Sukkur Medical College

Abstract

Community-acquired respiratory infections (CARIs) are a significant public health concern in Sindh, Pakistan, particularly in under-resourced district hospitals. This study investigates microbial etiologies and antibiotic sensitivity patterns in patients with respiratory symptoms from three district hospitals. A total of 310 sputum samples were analyzed using culture and sensitivity testing. The results highlight the predominance of bacterial pathogens such as Streptococcus pneumoniae, Haemophilus influenzae, and Klebsiella pneumoniae. Alarmingly high resistance to first-line antibiotics such as amoxicillin and co-trimoxazole was observed. The findings underline the urgent need for regional antimicrobial stewardship programs and updated empirical treatment guidelines.

Introduction

Respiratory tract infections (RTIs) remain a leading cause of morbidity and mortality globally, with a disproportionately high burden in low- and middle-income countries (LMICs) such as Pakistan (Lozano et al., 2012). In Sindh, where healthcare infrastructure in smaller districts is limited, CARIs continue to place strain on hospitals and lead to inappropriate and excessive use of antibiotics (Butt et al., 2013).

Antimicrobial resistance (AMR) is an escalating concern in Pakistan. Previous studies have reported variable microbial patterns and inconsistent antibiotic resistance profiles across regions (Zafar et al., 2008; Khan et al., 2019). Local surveillance is essential to guide empiric therapy, particularly in community settings where microbiological diagnostics are not routinely performed (Saleem et al., 2016).

This study by Akhtar and Hussain aims to document microbial prevalence and assess drug sensitivity in respiratory infections from small district hospitals in Sindh, with a view to supporting rational antibiotic use and informing regional clinical guidelines.

Methods

Study Design: A descriptive, cross-sectional study was conducted between June and November 2024 across three district hospitals: Hyderabad District Hospital, Sukkur Civil Hospital, and Larkana Medical Center.

Sample Collection: Sputum samples were collected from patients aged ≥5 years presenting with symptoms of lower respiratory tract infections (LRTIs), including productive cough, fever, and dyspnea. Patients with known tuberculosis or recent hospitalization were excluded.

Laboratory Analysis: Samples were cultured on blood agar and MacConkey agar and incubated at 37°C. Standard biochemical methods and Gram staining were used for bacterial identification. Antibiotic sensitivity testing was performed using the Kirby-Bauer disk diffusion method, interpreted according to CLSI guidelines (CLSI, 2022).

Data Analysis: SPSS v25 was used for statistical analysis. Descriptive statistics were applied to determine frequency distributions of pathogens and resistance rates.

Results

Demographics: A total of 310 sputum samples were analyzed: 162 (52.3%) from males and 148 (47.7%) from females. The mean patient age was 42.6 years (SD ± 16.8).

Pathogen Prevalence: Out of 310 samples, 238 (76.8%) yielded significant bacterial growth. The most frequently isolated organisms were:

• Streptococcus pneumoniae (31.5%)

• Haemophilus influenzae (22.7%)

• Klebsiella pneumoniae (18.5%)

• Moraxella catarrhalis (8.8%)

• Pseudomonas aeruginosa (6.7%)

• Mixed flora or others (11.8%)

Antibiotic Sensitivity: High resistance rates were noted for:

• Amoxicillin (68%)

• Co-trimoxazole (61%)

• Azithromycin (54%)

Higher sensitivity was observed for:

• Levofloxacin (72%)

• Ceftriaxone (64%)

• Amikacin (81%)

Multidrug resistance was particularly prevalent among Klebsiella pneumoniae and Pseudomonas aeruginosa isolates.

Discussion

This study confirms a high prevalence of classic respiratory pathogens, consistent with other reports from South Asia (Qureshi et al., 2017; Ali et al., 2020). The emergence of multidrug resistance, especially among Gram-negative organisms, is alarming and likely driven by unregulated antibiotic dispensing and lack of microbiological diagnostics in rural areas (Yousafzai et al., 2015).

The findings suggest that first-line empirical treatments commonly used in these settings may be ineffective in a majority of cases. This mismatch contributes to prolonged illness, increased healthcare costs, and potential complications (Chowdhury et al., 2020).

Updated regional treatment protocols based on microbial surveillance, as well as investment in diagnostic microbiology at the district level, are urgently needed. Public health education and prescribing oversight are also crucial to combat the rise of AMR (Farooqi et al., 2018).

Conclusion

Community-acquired respiratory infections in Sindh are predominantly caused by S. pneumoniae, H. influenzae, and K. pneumoniae, with significant resistance to commonly used antibiotics. These results underscore the importance of local antibiograms to guide empiric therapy and support targeted antimicrobial stewardship interventions.

References

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