Exclusion of Familial Benign Hypercalcaemia (FBH) in patients
with suspected primary hyperthyroidism (PHPTH). FBH is a
condition which can be mistaken for PHPTH because of some common
clinical and biochemical features. In contrast with PHPTH,
treatment of FBH by parathyroidectomy almost never results in
normalisation of serum calcium and surgery is therefore
Request on ICE
Patient should have been shown to have
Patient must fast overnight (10 hours)
Fasting serum and 2nd void fasting urine.
PTH should be measured at the same time
2 ml serum and 5ml urine
Yellow top (SST) tube (serum), white capped universal container
(urine) and Lemon top (Biochemistry SST) sample (for PTH)
Causes for Rejection
Unlabelled samples. Patient not fasting.
See laboratory report
Urine excretion is low in FBH. At a cut-off of 22 m mol/l
glomerular filtrate, sensitivity for the diagnosis of FBH is 95%
and specificity 92%.