Difficult to Treat Gram-Negative Bacteria—The Indian Scenario

Purpose of Review Over 50% of the infections in most ICUs in tertiary care centres in India are caused by difficult to treat (DTR) gram-negative bacteria. The options available for the treatment of these infections are quite limited. This review discusses the epidemiology of these DTR infections in India and explores the various treatment strategies for these infections which are relevant in an Indian setting. Recent Findings The most common organisms causing DTR infections in India are Klebsiella pneumoniae , Escherichia coli , Acinetobacter baumannii and Pseudomonas aeruginosa . The mechanisms of resistance in these organisms are not the same as those in DTR organisms prevalent in the western world. Treatment strategies recommended by western guidelines may not work in India. Management of these DTR organisms needs to be tailored to the situation in India. Summary Overuse of antibiotics has led to an alarming rate of DTR infections in Indian ICUs. The polymyxins are often the only drugs which are effective against many of these infections. Physicians in India and the government need to take urgent measures to control the spread of these organisms. Key points Antibiotic overuse has led to a situation where over 50% of infections in Indian ICUs are caused by DTR organisms. Carbapenemase production is the primary mechanism of resistance in carbapenem-resistant Enterobacterales (CRE). Efflux pumps, altered outer membrane porin and production of carbapenemases are all implicated in DTR Pseudomonas aeruginosa and Acinetobacter baumannii . KPC production is very uncommon in the CRE prevalent in India. Western guidelines may therefore not be relevant in India. The polymyxins (in combination) and ceftazidime/avibactam with aztreonam are the drugs most often used to deal with DTR gram-negative bacteria in India. Local delivery of antibiotics may be indicated in the management of these DTR infections in special sites like meningitis and pneumonia.