Mast-cell proliferation in postmenopausal osteoporosis.

Because mast cell proliferation has been reported in disorders of abnormal bone remodeling, we quantitated the number of mast cells in undecalcified section of iliac crest bone from 16 untreated women with postmenopausal osteoporosis and contrasted the findings to values from 10 normal women and 12 normal men. The mean number of marrow mast cells was greater in normal women than men (1.17 vs 0.40 cells per mm2, P less than 0.05). Compared to the normal women, osteoporotic women had a greater number of mast cells in the marrow (3.38 vs 1.17 cells per mm2, P less than 0.01). However, there was no statistically significant correlation between the number of marrow mast cells and either the patient's age or the severity of the bone lesions, as assessed by histomorphometry. Our findings confirm the association between increased numbers of mast cells and postmenopausal osteoporosis.