Hypocalcemia-related pustulosis: a case report

Hypocalcemia-related pustulosis is a rare dermatologic condition characterized by the development of sterile pustules on an erythematous base, associated with hypocalcemia. This condition is often misdiagnosed as generalized pustular psoriasis, presenting challenges in patient management. The novelty of this case lies in its emphasis on recognizing hypocalcemia as a potential cause of pustular eruptions, which can lead to significant clinical improvement once addressed.

A 34-year-old Moroccan woman with a history of total thyroidectomy and subsequent hypoparathyroidism presented with an acute, generalized pustular eruption. The lesions were diffuse, non-follicular, and symmetrically distributed across the trunk and limbs, accompanied by systemic symptoms such as muscle cramps and fatigue. Laboratory results confirmed severe hypocalcemia (serum calcium level: 52 mg/L; normal range: 85-105 mg/L) and low parathyroid hormone levels (6 pg/mL; normal range: 10-65 pg/mL), consistent with her prior hypoparathyroidism. A skin biopsy excluded psoriasis, steering the diagnosis toward hypocalcemia-induced pustulosis. The patient's pustular eruption resolved dramatically within 24 hours after the initiation of calcium and vitamin D supplementation, with complete clearance over the following days.

This case highlights the critical role of investigating electrolyte imbalances, particularly hypocalcemia, in patients with unexplained pustular eruptions. Prompt calcium correction led to rapid and complete resolution of the skin lesions, demonstrating the direct link between hypocalcemia and pustulosis. This emphasizes the importance of early diagnosis and appropriate management to ensure full clinical recovery.