Onycholysis associated with acute bacterial tonsillitis: case report

Marcelo Pacheco-Silva, Unidade Local de Saúde Almada-Seixal, Centro de Responsabilidade Integrada de Dermatovenereologia, Almada, Portugal Joana Reis, Unidade Local de Saúde Almada-Seixal, Centro de Responsabilidade Integrada de Dermatovenereologia, Almada, Portugal Katarina Kiesel-Rodrigues, Unidade Local de Saúde Almada-Seixal, Centro de Responsabilidade Integrada de Dermatovenereologia, Almada, Portugal João Alves, Unidade Local de Saúde Almada-Seixal, Centro de Responsabilidade Integrada de Dermatovenereologia, Almada, Portugal

Onycholysis is a common nail disorder with multiple causes. Transverse onycholysis bordered by a proximal erythematous rim is a typical manifestation of nail psoriasis. Its isolated onset after bacterial tonsillitis is uncommon and may pose a diagnostic challenge. We describe a previously healthy 20-year-old female who developed transverse onycholysis 2 weeks after treatment with amoxicillin/clavulanic acid for acute bacterial tonsillitis. Clinical examination revealed characteristic psoriatic nail changes, including a proximal erythematous-orange border and mild subungual hyperkeratosis. A diagnosis of post-streptococcal nail psoriasis was considered. She was treated with topical betamethasone/calcipotriol and advised on protective nail care, achieving marked improvement after 3 months. This case reinforces the association between streptococcal infections and psoriatic manifestations and highlights the diagnostic value of recognizing specific patterns of onycholysis. Early identification of psoriatic nail disease can prevent unnecessary investigations and enable timely, appropriate management.

Keywords: Onycholysis. Nail psoriasis. Streptococcal infection. Tonsillitis. Case report.