Rash decisions: diagnosing zinc deficiency in unexplained dermatitis 

Zinc is an essential micronutrient for the body and plays a crucial role in skin integrity, yet zinc deficiency remains an under-recognised cause of dermatitis, particularly in patients with predisposing risk factors. A male in his mid-30s with alcohol-related liver disease and ulcerative colitis presented with a widespread rash. Initial treatment for contact dermatitis and possible herpes simplex virus infection with topical steroids, antivirals and emollients was unsuccessful. His condition worsened, requiring intensive care admission. Imaging revealed bilateral pneumonia, and a skin biopsy returned inconclusive results. Dermatology review raised suspicion for an acrodermatitis enteropathica (AE)-like presentation. Although AE is typically inherited, acquired zinc deficiency can mimic its features in high-risk individuals. Subsequent serum zinc testing revealed low levels, and supplementation was initiated, resulting in rapid clinical improvement, supporting the diagnosis. This case highlights the need to consider micronutrient deficiencies, including zinc, in patients with severe dermatitis and significant risk factors. .