Osteomalacia is at present a relatively rare disease as its nutritional form, still very widely distri- buted and dominant in the first half of the 20 th century, practically disappeared due to systematic prevention. Types of osteomalacia which may be encountered nowadays are either secondary to some disease associated with calcium and vitamin D malabsorption or inborn or acquired defects of the metabolic action and effect of vitamin D are involved, or defects of the phosphate metabolism. These cases of osteomalacia due to their low frequency in the population easily escape diagnosis. Some of them are readily cured and it is regrettable that this opportunity is missed. The authors demonstrate this fact in the case-reports of three patients admitted to the Institute of Rheumatology during the last year.

        Key words: osteomalacia, rachitis, vitamin D