Antimicrobial resistance in hospitalized surgical patients: a silently emerging public health concern in Uganda

Abstract

Background: Surgical site infections (SSIs) are difficult to treat and are associated with substantially longer hospital stay, higher treatment cost, morbidity and mortality, particularly when the etiological agent is multidrug-resistant (MDR). To address the limited data in Uganda on SSIs, we present the spectrum of bacteria isolated from hospitalized patients, the magnitude and impact of MDR bacterial isolates among patients with SSIs.

Methods: A descriptive cross sectional study was conducted from September 2011 through April 2012 involving 314 patients with SSIs in the obstetrics & gynecology, general surgery and orthopedic wards at Mulago National Hospital in Kampala, Uganda. Wound swabs were taken and processed using standard microbiological methods. Clinico-demographic characteristics of patients were obtained using structured questionnaires and patients' files.

Results: Of the 314 enrolled patients with SSIs (mean age 29.7 ±13.14 years), 239 (76.1%) were female. More than half of the patients were from obstetrics and gynecology (62.1%, 195/314). Of 314 wound swabs taken, 68.8% (216/314) were culture positive aerobically, yielding 304 bacterial isolates; of which 23.7% (72/304) were Escherichia coli and 21.1% (64/304) were Staphylococcus aureus. More than three quarters of Enterobacteriaceae were found to be extended spectrum beta lactamase (ESBL) producers and 37.5% of S. aureus were Methicillin resistant S. aureus (MRSA). MDR occurred in 78.3% (238/304) of the isolates; these were more among Gram-negative bacteria (78.6%, 187/238) compared to Gram-positive bacteria (21.4%, 51/238), (p-value < 0.0001, χ2 = 49.219). Amikacin and imepenem for ESBL-producing Enterobacteriacea and vancomycin for MRSA showed excellent performance except that they remain expensive drugs in Uganda.

Conclusion: Most SSIs at Mulago National Hospital are due to MDR bacteria. Isolation of MRSA and ESBL-producing Enterobacteriaceae in higher proportions than previously reported calls for laboratory guided SSIs- therapy and strengthening of infection control surveillance in this setting.

Figure 1

Proportion of bacterial isolates from patients with surgical site infections (N = 304). Other g- bacteria: Enterobacter cloacae (10), Proteus mirabilis (7), Morganella morganii (6), Providencia spp (5), Citrobacter freundii (4), Serratia marcescens (1) and Leclercia adecarboxylata (1); Other g + bacteria: Streptococcus pyogenes (3), Streptococcus agalactiae (1), and Streptococcus spp (4).Acinetobacter spp: Acinetobacter baumanii (48) and Acinetobacter baumanii-calcoaceticus complex (4); Klebsiella spp: Klebsiella pneumonia (35) and Klebsiella oxytoca (4); Enterococcus spp: Enterococcus faecalis (21) and Enterococcus faecium (2).