Clinico-Epidemiological Characteristics of Severe Cutaneous Adverse Drug Reactions at the Kenyatta National Hospital

Severe Cutaneous Adverse Reactions (SCARs) including Stevens-Johnson Syndrome/Toxic Epidermal Necrolysis (SJS/TEN), Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS), Acute Generalized Exanthematous Pustulosis (AGEP) among others, are rare but potentially fatal drug-induced skin reactions. They pose a significant burden in resource-constrained settings like Kenya, where data on their epidemiology remains limited. Understanding the clinical characteristics of SCARs is crucial for improving patient outcomes, enhancing pharmacovigilance efforts and strengthening drug safety measures in Kenya. The study aimed to describe the clinical and epidemiological characteristics of SCARs, identify clinical phenotypes and describe the drugs associated with SCAR cases at Kenyatta National Hospital (KNH). A hybrid cross-sectional design was employed, comprising both retrospective and prospective data collection. A total of 102 patients were recruited via consecutive sampling. Data was collected through file reviews, clinical examinations, and interviews, focusing on demographics, clinical features and etiologies. Statistical analyses were conducted using SPSS-v26, with ethical approval from the KNH-UoN ERC. SJS/TEN was the most common phenotype (55.9%), followed by Drug-Induced Erythroderma (DIE) (17.6%) and Drug-Induced Erythema Multiforme (DIEM) (11.8%). The mean participant age was 29.4 years, with a slight female predominance (51%). Antimicrobials (60.8%) and anticonvulsants (13.5%) were the main implicated drug classes, with co-trimoxazole, ceftriaxone and carbamazepine identified as common culprits. HIV was the most prevalent comorbidity (23.9%). Common complications included acute kidney injury (11.8%) and drug-induced liver injury (8.8%). In-hospital mortality was 16.7%, with SJS/TEN having the highest case fatality rate (21.05%). SCARs in Kenya exhibit unique clinical and demographic patterns, with high mortality and organ involvement. Antimicrobials and anticonvulsants are major culprits. This underscores the need for early diagnosis, pharmacovigilance, public awareness, and healthcare provider training to improve patient outcomes. Future research should explore pharmacogenetics, long-term SCAR sequelae and the role of HIV in these severe reactions.