Endocrine Abstracts (2018) 59 P043 | DOI: 10.1530/endoabs.59.P043

Conventional treatment of chronic hypoparathyroidism results in suboptimal calcium homeostasis

Kazi M Alam1, Ahmad Bazil1, Trisha Kanani1, Nathan Lorde1, Faizanur Rahman1,2, Prashanth Patel1,2, Pankaj Gupta1,2, James Greening1,2, Vaya Tziaferi1, Savitha Shenoy1, Ragini C Bhake1, Miles J Levy1,2 & Narendra L Reddy1,2

1University Hospitals Leicester NHS Trust, Leicester, UK; 2University of Leicester, Leicester, UK.

Background: Conventional treatment for chronic hypoparathyroidism (CHP) is Vitamin-D analogues and calcium supplementation, not replacement of lacking hormone, as done in other hormone-deficiency states.

Objectives: Retrospective evaluation of CHP management in line with European Society of Endocrinology Guideline was undertaken, to assess adequacy of calcium-homeostasis and morbidity.

Methodology: Retrospective case-note and electronic-record review of 93 consecutive CHP cases (Post-surgical-56, Genetic-15, Autoimmune-6, Unknown-16), minimum 12 months follow-up between 1989 and 2017, was undertaken; audit No 9217.

Results: n=93 (67-females, 26-males), mean age 53 years (17-94yrs), mean duration of follow-up 13.5 years (1.2-29 years). 94%(87/93) treated with Vitamin-D analogues (86% alfacalcidiol, 8% calcitriol) with or without calcium-salts and 6%(6/93) calcium salts only. At follow-up, target range achieved: serum adjusted calcium 58% (54/93) (2.10 – 2.40 mmol/L); 24-hr urinary calcium 63% (17/27 performed) (2.5–7.5 mmol/L); serum phosphate 81% (75/93) (0.8–1.5 mmol/L); magnesium 92% (54/59 performed) (0.7–1 mmol/L) and vitamin-D 54% (43/79 performed) (>50 nmol/L). Regular monitoring was not undertaken in 71% (66/93) for 24-hr urinary calcium, 37% (34/93) for magnesium and 15% (14/93) for vitamin-D. 365 hypocalcaemia episodes (Ca < 2.0 mmol/L) in 62%(58/93); 56 hypercalcaemia episodes (Ca >2.60 mmol/L) in 18% (17/93) patients; 37% (34/93) required hospital admissions related to calcium-dysregulation resulting in 253 total inpatient days over 8 years (2010–2017). There was progression to CKD3 17% (16/93) and CKD4 2% (2/93); Renal stones 3; Nephrocalcinosis 1; Cataracts 4; unrelated death 5.

Discussion: 1. Conventional CHP management resulted in suboptimal calcium homeostasis in half of patients; 1/3rd required hospital admissions for calcium regulation.

2. Suboptimal monitoring of 24-hr urine-calcium and magnesium was noted.

3. Regular biochemical monitoring and dose adjustments may improve outcomes.

4. Evidence seems to be growing for recombinant human parathyroid hormone (1-84) for challenging cases.