Endocrine Abstracts

Aim: To determine whether cases of hypocalcaemia presenting via an emergency medical admissions unit (EAU) are appropriately investigated.

Background: Hypocalcaemia is a potentially life threatening abnormality, with a prevalence of 18% among hospital inpatients.^1,2 Risk factors include vitamin D deficiency, renal disease, hypoparathyroidism (typically post-neck surgery) and hypomagnesaemia. A reasonable investigational dataset comprises U+Es and serum levels of 25OHVitD, PTH, Mg, phosphate (P) and alkaline phosphatase (ALP).

Methods: The biochemistry database was interrogated for the year beginning 1st December 2008 to identify EAU patients with aCa <2.12 mmol/l. A secondary search was undertaken to identify any appropriate investigations.

Results: Of the 6384 individual patients with aCa checked on EAU, 184 were hypocalcaemic:

• 4% had all appropriate investigations done within 1 week.
• 25OHVitD and PTH levels were measured in 8.1% within a week of admission (21.7% across all time periods).
• Results were better for renal function (100%), ALP (100%), Mg (98.3%) and P (62%)
• Abnormal investigations: 25OHVitD<30 nmol/l)=50%; PTH>60 ng/l=66%; Mg<0.7 mmol/l=28%; ALP>120 U/l=35%; high/low P =60%; renal impairment=59%.
• Severe hypocalcaemia (aCa<2.01 mmol/l=bottom quartile of abnormals), was better investigated (25OHVitD and PTH measured in 40 and 58%, respectively).

Conclusions: Hypocalcaemia is less prevalent among patients presenting via EAU than in hospital inpatients, so the resource implications of investigating it properly are not huge. Yet this is not happening reliably, despite the high percentage of abnormal results when tests are done. Owing to delayed/incomplete investigation, therapeutic interventions will necessarily be delayed/omitted and hospital admissions likely to be correspondingly prolonged. Guidelines are in development to improve understanding of this issue.