Bacteriological profile and antibiogram in cases of pneumonia attending to tertiary care hospital

Abstract

Causative bacteria differ in different regions and this knowledge is necessary for formulation of local antibacterial guidelines. Diagnosing the microbial etiology of pneumonia is challenging because the site of infection (lung tissue) is not easily accessible for specimen collection and contamination by upper respiratory tract secretions.This study aimed to determine the bacterial profile of pneumonia cases and its antibiogram. A cross sectional, descriptive study was done at the Department of Microbiology involving 84 patients.Samples collected were sputum, induced sputum in children and endotracheal tube tip in mechanically ventilated patients following standard guidelines.All samples were processed within 2 hours of collection and subjected to Gram staining, incubated on Blood, Chocolate and Mac Conkey agar. Antibiotic susceptibility patterns, Methicillin resistance for Staphylococcus aureus and ESBL production among Gram negative bacteria was confirmed.Out of 84 cases studied, pathogenic growth was seen in 65(77.4%) and commensals were isolated in 19(22.6%) samples. The most common Gram negative bacteria was Klebsiella species(29, 42.7%) followed by Pseudomonas(20, 29.4%). Most common Gram positive bacteria was Staphylococcus aureus(4, 44.4%) and CONS(4, 44.4%). Staphylococcus aureus showed 100% resistance to Methicillin. Out of 20 Pseudomonas isolates, 6 were ESBL producers. Out of the remaining 48 Gram negative bacteria, 7 were ESBL producers.Incidence of pneumonia has increased due to lack of early diagnosis and multidrug resistance. The incidence of Gram negative bacteria has also increased tremendously. According to this study, most of the organisms are resistant to 3rd generation Cephalosporins.