The normal parathyroid gland at autopsy: the significance of stromal fat in adult patients.

Traditionally half of the cell population of the adult parathyroid gland is considered to be stromal fat. A marked decrease of stromal fat has been observed at autopsy of adult patients, the functional significance of which is unknown. In order to investigate this phenomenon, the stromal and parenchymal fat of the parathyroid glands of 33 adult patients who died with no known hormonal abnormalities were evaluated. Stromal fat was much less than 50 per cent, i.e., less than 10 per cent., in the majority of cases, while parenchymal fat was ample in all cases. This finding, especially if compared to cases with hyperparathyroidism, indicates the lack of functional specificity of change in stromal fat, whereas, alteration in parenchymal fat appears to be a better anatomical register of normal or abnormal parathyroid function.