Introduction: The association psoriasis and osteomalacia is very rare.
Exegesis: We report the case of a young girl, aged 17, who was consulting for ostealgia and erythematic and squamous cutaneous lesions. She had a staturo-ponderal delay, ostealgia and a bending of the general state. The osteo-articular examination showed a sternal protrusion with painful limitation of the movements of all joints. The dermatologic examination noted a dry erythrodermis to hick squamous with scalp's crush. The biological (hypocalcaemia, diminished urinary calcium) and radiological (demineralized bone with Looser-Milkmann fractures) results suggest an osteomalacia, diagnostic confirmed by the bone histological study that found out osteoid lines. The cutaneous biopsy was compatible with psoriasis diagnosis. A vitamino-calcic treatment associated to local nursing was undertaken. The evolution was favorable, noted by a cutaneous bleaching with a return back of the articular function. The present receding is of nine years.
Conclusion: Different studies underlined that outside of its action on the phosphocalcic metabolism, the vitamin D acts on the skin, especially on the proliferation of the keratinocytes that allowed its indication in the treatment of the psoriasis.