[Disease caused by lack of sunlight: rickets and osteomalacia]

In three patients, a 12-year-old Muslim Moroccan girl with polyarthralgia and a wobbling gait, a 47-year-old emaciated Hindustani man with muscle weakness and on antiepileptic drugs, and a heavily-veiled native Dutch woman aged 34 years with polyarthralgia and psoriasis, clinical, laboratory and radiologic examination led to the diagnoses of rickets (the first patient) and of osteomalacia (the other two). They recovered after calcium and vitamin D suppletion. After the discovery of vitamin D and the beneficial effects of sunlight and cod liver oil rickets and osteomalacia became rare. Recently these diseases have to be considered more often again because of changes in the composition of the Dutch population: more immigrants and (institutionalized) elderly who are prone to develop a vitamin D deficiency. Dietary and clothing habits should be investigated when a patient complains about diffuse (bone) pains. In case of minimal exposure to sunlight and a diet low in vitamin D the symptoms may be explained easily by a vitamin D deficiency. Once hypovitaminosis D is diagnosed, the therapy is simple and effective.