When not to ignore the normal results in endocrinology

Rafia Latif (FY1), Avinash Nanayakkara (CT1), Kasi Subbiah (ST3), Siva Sivappriyan (Consultant Endocrinologist & Diabetologist), Maidstone Hospital and Tunbridge Wells NHS Trust.

Primary Hyperparathyroidism (PHPT) is recognised biochemically as a spectrum of disease. One of the early phases is normocalcaemic primary hyperparathyroidism (NPHPT). Its incidence and prevalence is largely unknown.

There is lack of awareness amongst health care professionals on this. As clinicians, we need to recognise NPHPT promptly as patients are at increased risk of complications in the long run such as risk of fractures, nephrolithiasis, neuropsychiatric disease and cardiovascular disease.

NPHPT is confirmed with two measurements of normal calcium, with inappropriately high PTH levels, at 3-6-month intervals, after excluding secondary causes like vitamin D deficiency, renal failure, hypercalciuria, malabsorption syndrome etc.

Assessment of NPHPT includes annual bone profile and vitamin D. In addition, we must also screen for end organ damage with 3-5 yearly renal US (18.2% prevalence of nephrolithiasis), DEXA scan (57% prevalence of osteoporosis) and monitor for progression to PHPT (40%).

Follow up includes surveillance, medical management or definitive treatment with parathyroidectomy.

In our study, we have reviewed our current practice in Maidstone hospital.

Between June 2018 and September 2018, we identified 60 patients who had elevated PTH and normal calcium. All patients had their renal function checked. However, only 14 patients had repeat calcium levels done. Only 27 patients had their vitamin D levels assessed and only 39 patients had serum phosphate levels checked. 14 people had a DEXA scan, and 25 had renal US scan. 2 patients out of 65 were found to have NPHPT.

We are in the process of doing retrospective and prospective analysis, including recruiting more patients into this study.

Our aim is to formulate a local guideline to identify and treat NPHPT promptly.

Our questions to the audience are;

  1. Are you aware of NPHPT and its prevalence in your local population?
  2. Do you have any systems in place in your MDT environment?
  3. What will be the potential cost implications to the services?