Endocrine Abstracts

Introduction: Impetigo herpetiformis is a rare dermatological disorder, mimicking generalized pustular psoriasis. It is characterized by a generalized erythema-pustular eruption accompanied by fever. Its etiopathogenesis is poorly coded but triggers have been identified such as hypocalcemia in more than half of cases and pregnancy. We report a case of severe hypocalcemia secondary to hypoparathyroidism revealed by impetigo herpetiformis.

Case report: Forty-six-year-old patient with lobo-ishmectomy at 12 years of age with iatrogenic hypoparathyroidism undergoing replacement therapy, had been presenting for 15 days erythematous cupboards which had recently confused, with a notion of stopping the ergocalciferol for 2 months. The admission examination found a febrile patient at 38.5°C with erythroderma covering more than 80% of the skin surface, strewn with afollicular pustules. The mucous membranes were spared. The neurological examination was without abnormalities. Biology revealed severe hypocalcemia at 57 mg/l, hyperphosphoremia, with PTH at 2 μg/ml (VN> 24). The ECG showed a long corrected QT space. The histological aspect was that of impetigo herpetiformis. The patient was treated with calcium infusion and 3 g/day of oral calcium and 2 microgram of ergocalciferol per day. The evolution was marked by the regression of the pustules of more than 90% of the lesions with appearance of desquamation plaques wide at the 4th day, with a complete disappearance of the lesions at the 8th day, concomitant with the correction of the calcemia.

Discussion: Impetigo Herpetiformis is a rare skin disorder. The factors implicated are mainly hypocalcemia and pregnancy, then cortisone withdrawal, topical corticosteroids with high activity under occlusive dressing, bethalactamines, lithium, stress and alcohol intoxication. Cadherins are essential for cell adhesion and these molecules are calcium-dependent. Vitamin D plays an important role in the differentiation and proliferation of skin cells.

Conclusion: All observations of amicrobial pustulosis illustrate the definite relationship between the rash and the calcium-PTH-vitamin D axis, presumably by hypocalcemia.