To assess relationship between serum calcium level and localization studies and management outcome.
Retrospective analysis of data for patients referred by primary care for hypercalcemia from 1/3/2019 to 1/3/2020 to the Endocrinology department at Royal Berkshire Hospital. The sample size was 63 which excluded normo-calcemic hyperparathyroidism as well as MEN1/2 patients.
The average age of cohort was 68.6 years with female preponderance (80.5%). The average referral adjusted calcium was 2.8 mmol/l and PTH was 12.5 mmol/l. End organ damage in the form of osteopenia and osteoporosis was highly prevalent at 60.3%. The sensitivity for USS was 47.6% and MIBI was 50.8%. The concordance between the two modalities was 71.4%. The lower limit of adjusted serum calcium level cut off for positive USS was 2.65 mmol/l and for positive MIBI was 2.62 mmol/l with p value of 0.00025. In terms of management outcome, 57.1% of cohort were referred to ENT team for surgery and the rest were conservatively managed.
Hypercalcemia forms a significant proportion of referrals to endocrinology service. Primary hyperparathyroidism is the most common cause of hypercalcaemia, with an estimated prevalence of about 17 cases per 1000 adults. This study reiterated the established expected demographics of patients with primary hyperparathyroidism i.e., female preponderance with increasing prevalence in older adults . Half of the referrals were asymptomatic. About two third of the cohort had osteopenia and osteoporosis, a criterion that enables eligibility for surgical intervention if appropriate. The pick-up rate of parathyroid USS and scintigraphy were comparable at around 50%, with a discordance of 28.6% between them. The lower limit for adjusted calcium above which both the USS and SestaMIBI provided positive finding was 2.62 mmol/l which is reassuringly just above the lower limit cut off for NICE diagnostic criteria for hypercalcemia. It is important to note though that normo-calcemic hypercalcemia were not included in this study. With respect to management outcome, a significant 57.1% of cohort were referred to ENT team for targeted (63.9%) or exploration surgery (36.1%) depending on image findings. The rest were conservatively managed with either cinacalcet (34.6%) or wait and watch approach (65.4%). It is interesting to note that 80% of patients with adenoma on USS translated to a surgical outcome. This held true even in the event of discordance with MIBI scan, revealing this modality being favoured by ENT team.
22 May 2021 - 26 May 2021