Demographics and clinical manifestations of patients with Raoultella terrigena infections: A Retrospective Single Center Study from Karachi, Pakistan

Background: Raoultella terrigena (formerly Klebsiella terrigena) is an environmental gram-negative rod. It can cause infections in humans, especially in immunosuppressed patients and tends to be multi-drug resistant, limiting treatment options. There is lack of data on clinical presentation and outcomes of infections due to this organism. In this study; we describe the clinical features (presenting complaints, co-morbid diseases, complications, etc.), available treatment options, and outcomes (hospital/ICU stay, mortality) of patients with R. terrigena infections, seen retrospectively over six years. Material and Methods: A cross-sectional study was conducted on all adult hospitalized patients with clinical specimens positive for Raoultella terrigena at a 700-bedded tertiary care hospital in Karachi, Pakistan, from January 2013 to December 2018. Results: We identified 58 patients with R. terrigena isolated from different cultures specimens, of which n=12 (22.6%) were colonizers. The median age was 61.5 years (IQR=43-71), and most were male (n=28). The most common site of infection was the respiratory tract in 28.3%, then urinary tract in 26%, and central line in 26.1%. Amongst infected cases, 37% had septic shock, 45.7% had respiratory failure. Conclusion: R. terrigena is a multi-drug-resistant organism with a high mortality rate and can cause hospital-acquired respiratory tract infections in patients. Keywords: Raoultella terrigena, Klebsiella terrigena, Raoultella species, Klebsiella species.