Test your diagnostic skills in our regular dermatology quiz. What is the cause of these dystrophic nail changes, with increasing erythema to the lateral nailfolds over the last four months?
A 15-month-old boy presents with chronic recurrent dystrophy affecting the nails of both great toes since birth (Figure). His parents describe the toenails as ‘ingrown’ and have noticed more prominent erythema to the lateral hallux nailfolds over the last four months. All other nails of his feet and hands are normal.