Thesis

The skin sore trial: exploring a better treatment option for impetigo in Indigenous children living in remote Australia

Abstract:
Impetigo is prevalent among Australian Indigenous children living in the&​nbsp;Northern Territory. The cause of this endemic skin infection is multifactorial&​nbsp;including household overcrowding, poverty, endemic scabies and fungal skin&​nbsp;infections, tropical climate, insect bites and minor trauma. Although impetigo is&​nbsp;widespread, affecting up to 50% of children in a community at one time, care&​nbsp;seeking for treatment of impetigo does not reflect this burden accurately,&​nbsp;possibly due to awareness of the painful injection prescribed. A better treatment&​nbsp;is needed.This thesis presents the first randomised controlled trial conducted amongst&​nbsp;remote living Indigenous Australian children on the treatment of extensive&​nbsp;impetigo, and one of the largest impetigo trials worldwide. Methodological gaps&​nbsp;were addressed, with studies published on the susceptibility of Streptococcus&​nbsp;pyogenes to trimethoprim-sulphamethoxazole (SXT), the transport of impetigo&​nbsp;swabs in remote settings and photography protocols for capturing and scoring&​nbsp;sores. The principal findings are:1. Either of two short courses of SXT are non-inferior to standard treatment of&​nbsp;impetigo with intramuscular benzathine penicillin G (BPG) – published in The&​nbsp;Lancet;2. S. pyogenes remains the key driver of impetigo in our region; and3. S. pyogenes is susceptible in vitro to SXT, and SXT is effective in vivo for the&​nbsp;treatment of skin infections caused by S. pyogenes.These findings will inform the management of children with impetigo in remote&​nbsp;Indigenous communities and have already been incorporated into treatment&​nbsp;algorithms and guidelines regionally and nationally. This provides a simple,&​nbsp;short-course antibiotic regimen that is palatable, inexpensive and has a low side effect&​nbsp;profile, as an alternative to an injection of intramuscular penicillin, which&​nbsp;has been the standard of care for more than 20 years. Ongoing surveillance will be needed to understand how this new regimen is utilised and whether&​nbsp;widespread use for a common condition will alter antibiotic resistance profiles.