Endocrine Abstracts

Background: Parathyroid hormone (PTH) secretion in response to hypocalcemia was found to be altered in people living with HIV (PLWH) and HIV infection has therefore been acknowledged as a potential reason for hypoparathyroidism (HPO).

Aim: To describe the prevalence of HPO in a population of PLWH.

Methods: Monocentric, retrospective sub-study of the Munich ArcHIV cohort.

Results: 579 patients (461 men (79.6%)) were included in the study with a median age of 48 (40–54) years. In 496 patients, albumin concentration was available in and the prevalence of HPO was 15.3% (n=76) and 8.3% (n=41) in 2016 and 2017, respectively. In 14 patients (1.4%) HPO was found in both years. One of these patients presented with a medical history of cervical irradiation due to Hodgkin’s lymphoma. Of 14 patients with HPO in both years, 10 (71.4%) were on tenofovir disoproxil fumarate (TDF) at the time of PTH measurement in both years (P=0.008). Therefore, exposure to TDF was associated with a risk ratio of 4.2 (1.3–13.1).

Discussion: The prevalence of HPO in our cohort of PLWH was unexpectedly high at 1.4%. Except for one patient, no “traditional” explanation for hypoparathyroidism could be found. Different from findings in “classical” hypoparathyroidism, phosphate levels were not higher in patients with HPO compared to controls; contrary, we even found a trend towards a higher frequency of at least one episode of hypophosphatemia. This might however be attributable to the more frequent use of TDF in patients with HPO, as TDF has been associated with increased phosphate excretion and lower phosphate levels before.

Conclusion: HIV-infection and antiretroviral therapy seem to be associated with a higher prevalence of HPO. The limitations of a retrospective study warrant further investigations on this topic.