Epidemiology and antibiotic choice in hand infections requiring surgical drainage : a retrospective study of 414 cases

Abstract

BACKGROUND: Hand infections are exceedingly common conditions that are associated with significant morbidity. Sound anatomical and microbiological knowledge is required to effectively manage these entities and to prevent or limit disability. The cornerstones of treatment remain surgical drainage of pus collections, judicious use of antimicrobial agents, and rehabilitation. Empiric antibiotic guidelines should target common organisms based on regional aetiological patterns, with strong consideration of host factors. The aim of this study was, therefore, to evaluate the epidemiology and suitability of empiric antibiotics in hand infections requiring surgical drainage at a centre in the Northern Cape province of South Africa. METHODS: A retrospective chart review of patients with hand infections requiring surgical drainage was conducted over a 24-month period between 1 January 2018 and 31 December 2019. The data was collected at an institution in the Northern Cape, which serves as the referral centre for the majority of the rural areas in the province. Culture results were obtained from the specimens collected during surgical drainage and debridement, and were accessed from the National Health Laboratory Service (NHLS) website. RESULTS: Of the 414 specimens, 388 yielded positive cultures and 26 had no growth. In total, 403 organisms were cultured. This consisted of 374 Gram-positive organisms (93%), and 29 Gram-negative organisms (7%). Staphylococcus was the most common organism isolated in 368 cases. Threehundred and forty (84%) of these were methicillin-sensitive Staphylococcus aureus (MSSA), and 24 (6%) were methicillin-resistant Staphylococcus aureus (MRSA). With the low rates of MRSA cultured, caution should be exercised when generalising these results for the population. The mean age of patients was 31 years 10 months (standard deviation 14 years 5 months), with a 4:1 ratio of males to females, and the most common site of infection was the webspace (27%). CONCLUSION: Staphylococcus is still overwhelmingly the most common causative organism in hand infections in this population. Low numbers of MRSA were detected, but this still represents a five-fold increase in the region over the past decade. Urgent surgical drainage and bacteriological sampling before empiric antibiotics that target local common organisms remains the mainstay of treatment. Consultation with an infectious disease specialist to maximise efficacy of antibiotic selection and dosing can limit the growing problem of antibiotic resistance. In this setting, the use of cloxacillin as a single empiric agent is still recommended, though the increasing prevalence of MRSA needs to be monitored.