Could primary hyperparathyroidism-related hypercalcemia induce hypercalcitoninemia?
OBJECTIVE
To determine if primary hyperparathyroidism (pHPT) per se may be responsible of hypercalcitoninemia. pHPT induces chronic hypercalcemia that should be expected to be a potential stimulatory pathway of calcitonin (CT) secretion and to cause hypercalcitoninemia.


METHODS
We studied relationships between CT and pHPT-related chronic hypercalcemia in 122 patients aged 25-83 years who underwent parathyroid surgery. CT, calcium and PTH plasma levels were measured in all patients preoperatively. CT was measured by a current immunometric assay specific of mature CT monomer.


RESULTS
Of our 122 patients with pHPT-related hypercalcemia, 120 (98.4%) had normal CT values of less than 10 pg/ml and two (1.6%) exhibited a mildly increased CT above 10 pg/ml (11 and 12 pg/ml, respectively). We evidenced no relationship between CT and calcium level or PTH level.


CONCLUSIONS
Chronic pHPT-related hypercalcemia per se does not cause hypercalcitoninemia. The finding of pHPT concomitant with high CT levels should raise suspicion of multiple endocrine neoplasia type 2A.
Conte-Devolx
B
B
Faculté de Médecine, Université de la Méditerranée et Service d'Endocrinologie, Diabète et Maladies Métaboliques, Marseille, France.
Morlet-Barla
N
N
Roux
F
F
Sebag
F
F
Henry
J F
JF
Niccoli
P
P
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002116:Calcitonin / Q000097:blood*; D002118:Calcium / Q000097:blood; D005260:Female; D006801:Humans; D006934:Hypercalcemia / Q000150:complications* / Q000209:etiology*; D049950:Hyperparathyroidism, Primary / Q000150:complications*; D008297:Male; D008875:Middle Aged; D018813:Multiple Endocrine Neoplasia Type 2a / Q000097:blood; D010280:Parathyroid Glands / Q000601:surgery
D002116:Calcitonin; D002118:Calcium