Review Parathyromatosis: a rare yet problematic etiology of recurrent and persistent hyperparathyroidism Mirella P. Hage, Ibrahim Salti, Ghada El-Hajj Fuleihan ⁎ Department of Internal Medicine, Division of Endocrinology, American University of Beirut-Medical Center, Riad El Solh 1107 2020, Beirut, Lebanon ARTICLE INFO ABSTRACT Article history: Received 19 September 2011 Accepted 2 November 2011 Recurrent or persistent hyperparathyroidism is an uncommon yet challenging clinical problem, and parathyromatosis is one of its very rare causes. In this minireview, we review causes of recurrent hyperparathyroidism and all cases of parathyromatosis available in the literature. The clinical course of a case of parathyromatosis with the longest follow-up (1977-2011) is described. Similar cases reported between 1975 and the present are reviewed and analyzed to characterize the clinical presentation, course, and management of this rare condition. Parathyromatosis, which is benign parathyroid tissue seeding, has been detailed in 35 patients in the English literature. The majority were female subjects, with end-stage renal disease, in their fifth to sixth decade of life. In most cases, the diagnosis was made intraoperatively; and the condition was often refractory to surgery. A calcimimetic agent was used in 5 cases with end-stage renal disease; serum calcium and/or parathyroid hormone levels decreased in 4 subjects, but only one was reported to experience increments in bone density. Medical management combining a calcimimetic with a bisphosphonate may therefore be a preferred alternative. © 2012 Elsevier Inc. All rights reserved. 1. Causes of persistent or recurrent hyperparathyroidism Primary hyperparathyroidism (PHPT) is defined as “the disease in which, in the absence of a known stimulus, one or more parathyroid glands secrete excess parathyroid hormone, producing hypercalcemia”[1]. It is most commonly caused by a single adenoma, and surgery is most often curative. Those not cured have either persistent or recurrent disease. When hypercalcemia fails to resolve after parathyroidec- tomy (PTX), the disease is termed persistent, whereas recurrent HPT refers to reappearance of hypercalcemia after a normocalcemic period of at least 6 months post- PTX [2]. Several factors have been associated with initial treatment failure or recurrence of the disease including inexperience of the operating surgeon; ectopic or supernu- merary glands; multiglandular disease; parathyroid carci- noma; and, rarely, parathyromatosis. METABOLISM CLINICAL AND EXPERIMENTAL 61 (2012) 762 – 775 Author contributions: M Hage, I Salti, and G El-Hajj Fuleihan were directly involved in patient care, reviewed the data relevant to the article, and edited the manuscript before submission. M Hage conducted the literature search and summarized its results. M Hage and G El-Hajj Fuleihan wrote the article. ⁎ Corresponding author. WHO Collaborating Center for Metabolic Bone Disorders, Division of Endocrinology, Department of Internal Medicine, American University of Beirut-Medical Center PO Box 11-0236, Riad El Solh 1107 2020, Beirut, Lebanon. Tel.: +961 1 737868; fax: +961 1 745321 or 961 1 744464. E-mail address: gf01@aub.edu.lb (G. El-Hajj Fuleihan). 0026-0495/$ – see front matter © 2012 Elsevier Inc. All rights reserved. doi:10.1016/j.metabol.2011.11.001 Available online at www.sciencedirect.com Metabolism www.metabolismjournal.com