Multi-drug resistance bacteria predict mortality in blood stream infection in a tertiary setting in Tanzania

Abstract

25 Background: Blood-stream infections (BSI's) are serious and life-threatening infections 26 associated with high mortality and morbidity. In resource limited settings, there is paucity of data 27 on predictors of outcome in patients with BSI. This study aimed at examining the predictors of 28 mortality in patients with BSI as well as bacteria causing BSI.29 Methods and Materials: This was cross-sectional study conducted in Muhimbili National 30 Hospital between April and May 2018. Blood culture results from all inpatients at clinical 31 microbiology laboratory were recorded and clinical information were retrieved retrospectively 32 from the files. Bacteria from positive blood culture were identified and antimicrobial 33 susceptibility was performed.34 Results: The overall prevalence of BSI was 11.4% (46/402), with case fatality rate of 37%.35 There was significant high rate of BSI in patient who had died compared to those survived p= 36 0.008. Gram-negative bacteria (74%) were the common cause of BSI, with predominance of 37 Enterobacteriaceae (22), followed by Pseudomonas aeruginosa (11). Majority (70.5%) of the 38 bacteria isolated from patients with BSI were multi-drug resistant. Forty six percent of 39 Pseudomonas aeruginosa were resistance to meropenem. Sixty eight percent 68.2% (15/22) of 40 Enterobacteriaceae were ESBL producers. Carbapenemases production were detected in 27% 41 (3/11) of Pseudomonas aeruginosa and in one Proteus mirabillis. Forty percent (40%) of 42 Staphylococcus aureus were methicillin resistant Staphylococcus aureus (MRSA). Positive blood 43 culture (cOR 7.4, 95%CI 1.24 -43.83, p 0.03) and admission in ICU cOR 4 (95%CI 1.7 -9.41, 44 p 0.001) were independent factors for mortality in suspected BSI. Isolation of Multi-drug 45 resistant bacteria was independent predictor for mortality in confirmed BSI (cOR 7.4, 95%CI 46 1.24 -43.83, p 0.03). 3 47 Conclusion: The prevalence of BSI was 11.4%, with majority of bacteria in BSI were MDR. 48 Positive blood culture and MDR were predictors for mortality. 49 50 Introduction 51 Blood stream infection (BSI) is a life threatening and has been associated with increased 52 mortality, morbidity and health care costs (1). Often, multi-drug resistant bacteria causing BSI 53 attribute to disproportionate poor outcomes compared to susceptible bacteria (2, 3). The 54 incidence and prevalence of BSI varies considerably between developed and developing 55 countries (4-6). Nevertheless, epidemiology of BSI in both community and hospital settings is 56 evolving. Besides that, data on rapid changing bacterial etiology of BSI in Tanzania is scarce. 57 58 Treatment of BSI in resource limited setting is largely empiric with broad spectrum antibiotics. 59 Empiric treatments often fail to target the correct pathogens effectively, leading to treatment 60 failures and increasing mortality (1, 7). To address these, clinical microbiology laboratories may 61 play important roles on effective management of BSI. Prompt reporting of results coupled with 62 identifying criti...