Surgical Site Infections following the surgical timing for depressed skull fractures in a sub-Saharan tertiary hospital: Bacteriological and antimicrobial susceptibility patterns

Introduction: Surgical site infections (SSI) remain a major cause of morbidity and mortality following surgery for traumatic brain injury (TBI). The development of SSI from cranial neurosurgical procedures represents a significant threat to life and often requires immediate medical/surgical intervention. The timing of surgery and the patterns of infection remain a big challenge in the management of stable TBI patients with depressed skull fractures (DSF). We aimed to determine bacteriological and antimicrobial susceptibility patterns in SSI following the timing of debridement and elevation of DSF from Mulago hospital in Uganda.

Methods: This was a prospective cohort study that was carried out in neurosurgical wards of Mulago Hospital. Patients were recruited from the emergency department within 24 hours of injury and followed up perioperatively to record the incidence of SSI according to WHO criteria. During dressing changes, we swabbed any discharge from surgical sites aseptically and processed as per standard operating procedures in appropriate culture media. We performed susceptibility testing on Mueller Hinton agar.

Results: A total of 108 patients were enrolled with mean-age=23.6 years and 92.6% males. The prevalence of SSI was 16/108(14.8%), mainly superficial SSI, and relatively high among patients operated on after 48 hours of injury. Gram-negative microorganisms constituted the highest number of isolates with 11/17(64.7%). There were 4/17(23.5%) enterococcus species and 2/17 (11.8%) S. aureus Gram-positive bacteria isolated. Among the Gram-negative microorganisms, Escherischia coli species 4/17(23.5%) and K. pneumoniae 4/11(23.5%) were predominant isolates. Deep SSI was associated with E. coli. Gram-positive isolates showed resistance to most of the commonly prescribed antibiotics.

Conclusion : The prevalence of SSI was relatively high after delayed surgery of DSF with the predominance of Gram-negative bacteria in the isolates with at least two antibiotics resistance patterns. We recommend early surgical intervention for DSF, especially the compound types, with strict infection control measures to reduce SSI and revise antibiotherapy protocol.