Lower Respiratory Tract Infections in Intensive Care Units. A Four Year Study from North India

Title: Lower respiratory tract infections in intensive care units. A four year study from North India.

Study Design: Prospective study

Place and Duration of Study: Sher-i-Kashmir Institute of Medical Sciences, Srinagar Kashmir. Four years (July 2010 and June 2014).

Methodology: A prospective analysis of respiratory specimens from various intensive care units (ICUs) was done over a period of four years. Antimicrobial susceptibility of culture positive isolates to various antibiotics was performed as per Clinical Laboratory Standards Institute (CLSI) guidelines. Gram-negative bacteria (GNB) were screened for extended spectrum β-lactamase (ESBL) and metallo-β-lactamase (MBL) production; whereas methicillin and vancomycin resistance was searched in staphylococci and enterococci isolates respectively.

Results: The frequencies of Gram-positive and Gram-negative bacteria were 26% and 68% respectively with yeast recovered in 8% of the specimens. K. pneumoniae and Acinetobacter spp were the most common Gram-negative bacteria and S. aureus the most common Gram-positive one. High level resistance to all the antimicrobials was seen; with K. pneumoniae being the most multidrug resistant GNB isolated in the ICU setting. ESBL production was also highest in K. pneumoniae isolates (67.1%). Also 59.6% of Acinetobacter isolates were found to be MBL producers. Methicillin resistance was seen in 48% of S. aureus and 85.5% of coagulase negative staphylococci (CoNS) isolates with vancomycin resistance seen in 6.7% of enterococcal isolates.

Conclusion: An increasing trend over the years in the antibiotic resistance of respiratory pathogens in ICUs of this north Indian state was seen that calls for urgent measures to limit their continued rise.