Reversed whole PTH/intact PTH ratio as an indicator of marked parathyroid enlargement: five case studies and a literature review.

Abstract

Parathyroid hormone (PTH) levels detected by intact PTH assays are generally higher than those detected by the whole PTH assay because the latter does not detect non-(1-84) PTH fragments, mainly PTH (7-84). Rare exceptions to this rule have been reported in patients with severe primary or secondary hyperparathyroidism and parathyroid carcinoma. Overproduction of an N-form of PTH other than PTH (1-84) has been observed in the sera of these patients. We report five additional cases with the reversed whole PTH/intact PTH ratio associated with severe hyperparathyroidism in haemodialysis patients. Three patients demonstrated enlargement of a single hypervascular gland, whereas the other two had undergone surgical parathyroidectomy and later showed recurrent hyperparathyroidism due to progressive autograft hyperplasia. In the case of a single enlarged gland, the pathological pattern and heterogeneous expression of parathyroid adenomatosis 1/cyclin D1 suggested it to be a single nodule of uraemic hyperparathyroidism rather than sporadic primary adenoma. These cases suggested that the reversed whole PTH/intact PTH ratio could be an indicator of marked parathyroid enlargement. Further studies are required to elucidate the clinical significance of the reversed whole PTH/intact PTH ratio in haemodialysis patients.

• Authors: Hirotaka Komaba, Yoko Takeda, Jeongsoo Shin, Reika Tanaka, Takatoshi Kakuta, Yoshihiro Tominaga, Masafumi Fukagawa
• Journal: NDT plus (NDT Plus) Vol. 1 Issue Suppl 3 Pg. iii54-iii58 (Aug 2008) ISSN: 1753-0784 [Print] England
• PMID: 25983975 (Publication Type: Journal Article)