Rash morphology as a predictor of COVID‐19 severity: A systematic review of the cutaneous manifestations of COVID‐19

Approximately 6% of those with COVID‐19 will experience cutaneous manifestations. Examining data from this cohort could provide useful information to help with the management of COVID‐19. To that end, we conducted a systematic review primarily to assess rash morphologies associated with COVID‐19 and their relationship with disease severity. Secondary outcomes include demographics, distribution, dermatological symptoms, timeline, diagnostic method and medication history. The literature was searched for all patients with skin manifestations thought to be related to suspected or confirmed COVID‐19. Patients with a history of dermatological, rheumatological or occupational skin disorders were excluded. Of the 2056 patients selected, the most common morphologies were chilblain‐like lesions (54.2%), maculopapular (13.6%) and urticaria (8.3%). Chilblain‐like lesions were more frequent in the younger population (mean age 21.5, standard deviation ± 10.8) and were strongly linked with milder disease, not requiring an admission (odds ratio [OR] 35.36 [95% confidence interval {CI} 23.58, 53.03]). Conversely, acro‐ischaemia and livedo reticularis were associated with worse outcomes, including a need for ICU (OR 34.01 [95% CI 16.62, 69.57] and OR 5.57 [95% CI 3.02, 10.30], respectively) and mortality (OR 25.66 [95% CI 10.83, 60.79] and OR 10.71 [95% CI 4.76, 24.13], respectively). Acral lesions were the most common site (83.5%). 35.1% experienced pruritus, 16.4% had pain and 4.7% reported a burning sensation. 34.1% had asymptomatic lesions. Rash was the only symptom in 20.9% and occurred before or alongside systemic symptoms in 12.4%. 28.3% had a positive polymerase chain reaction nasopharyngeal swab and 5.4% had positive antibodies, while 21.9% tested negative and 45.1% were not tested. In conclusion, COVID‐19 causes a variety of rashes, which may cause symptoms and add to morbidity. Rash type could be helpful in determining COVID‐19 prognosis.