Parathyroid-hormone-related protein in sarcoidosis

Parathyroid-hormone-related protein (PTHrP) is the main mediator of the humoral hypercalcemia of malignancy. It is also detected in many normal adult and fetal tissues. Altered calcium metabolism occurs in sarcoidosis, and two cases of sarcoidosis with hypercalcemia and elevated plasma PTHrP are described. An archival study of 20 lymph node biopsies with the pathological diagnosis of sarcoidosis was performed. Immunohistochemistry using a polyclonal antiserum to human PTHrP and in situ hybridization using a riboprobe to human PTHrP were performed on the lymph node biopsies. Immunohistochemistry for PTHrP was also performed on the biopsies from the two cases with elevated plasma levels. Immunohistochemical analysis detected PTHrP in macrophages within granulomata in 17 of the 20 (85%) biopsies. In situ hybridization detected a positive signal for messenger RNA in the granulomata of 11 of 19 (58%) biopsies. PTHrP immunoreactivity and PTHrP gene expression are present in sarcoid granulomata. PTHrP may contribute to the hypercalcemia of sarcoidosis.

The use of corticosteroids in dermatological practice

OBJECTIVE

To discuss the various uses of corticosteroids in patients with skin diseases.

DATA SOURCES

All relevant literature published since 1950 was reviewed and 33 studies were selected.

CONCLUSIONS

Systemic and topical corticosteroid preparations are used commonly in patients with skin diseases. Oral administration of steroids is particularly useful in acute hypersensitivity diseases, connective tissue diseases, immunological blistering diseases, and the commoner dermatoses when they are very severe and widespread. Topical steroid preparations are mainly used in the different forms of dermatitis, but are also useful in psoriasis and a number of other skin diseases. If potent topical steroid preparations are used for too long, or in excessive quantities, side effects will be encountered as a direct effect on the skin, for example atrophy, and as a result of systemic absorption, for example, hypothalamic-pituitary-adrenal suppression and Cushing's syndrome.