Abstract
BACKGROUND: Studies have identified significant morbidity and mortality with necrotising soft tissue infections relating to invasive group A Streptococcus (iGAS). However, no studies have analysed the reconstructive, functional and psychological outcomes of invasive group A Streptococcus infections across its clinical spectrum, including the more common non-necrotising presentations. This study was a retrospective cohort study that aimed to review as primary outcomes the management, reconstructive burden and functional outcomes of soft tissue iGAS infections at a tertiary-care U.K. Plastic Surgery unit between 2013 and 2022. The secondary outcome was to identify associations between patient factors and limb amputation and mortality. METHODS: All positive iGAS cultures isolated in patients aged 16 and over were identified. Medical records, operative records, and microbiology samples were examined. RESULTS: 96 cases of iGAS were identified in 95 patients over the study period. 63 patients (66%) were male; 34 patients (36%) were current smokers; and 35 patients (37%) were immunocompromised, including 18 patients (19%) with diabetes. 88 cases (92%) affected the upper or lower limbs, with 11 cases (13% of limb iGAS) requiring amputation of the involved digit or limb. Reconstructive surgery was performed in 15 cases (16%), requiring a mean number of 3.7 ± 1.88 operations. Reconstruction methods involved acelluar dermal matrices and/or skin grafts (14 cases; 15%) and locoregional flaps (8 cases; 8.3%). At follow up, 13 cases (14%) had functional complications relating to their iGAS episode, including neuropathic pain and limited movement. Mortality was 5.2% (5 patients) within the index admission and 7.3% (7 patients) within 90 days. Diabetes was significantly associated with 90-day mortality (p = 0.023; odds ratio [OR] 7.05, 95% confidence interval [CI] 1.41–35.00) and amputation (p = 0.033; OR 4.51, 95% CI 1.19–17.19). Other systemic comorbidities were not significantly associated with mortality or amputation. CONCLUSIONS: Soft tissue iGAS infections principally affect the limbs and require multimodal management to mitigate the high rates of infection-related morbidity and mortality. Diabetes is significantly associated with higher amputation and mortality rates in our study population. Appropriate services should be in place to manage long-term functional disability and mental health morbidity after iGAS.