Written by J. Craig Egan, MD, FACS
Parathyroid disease in children may arrise from a variety of causes.The parathyroid glands, located in the lower neck near the thyroid gland, are responsible for calcium and phosphate balance. Parathyroid hormone (PTH) is secreted by these glands and acts to help the kidneys produce vitamin D, which, in turn, stimulates the intestine to absorb calcium. PTH also acts to draw calcium out of the bones into the bloodstream. It is suggested that children with symptoms of fatigue, headache, nausea, abdominal pain, emesis, polydipsia, diarrhea, depression, or joint pain that is not directly attributable to some other process or that does not resolve should have a screening serum calcium and PTH level obtained.
There are many causes of high calcium (hypercalcemia). High PTH, or hyperparathyroidism, is one potential cause. Tests for this usually include blood tests, urine tests, and xrays. Ultrasonography is a reliable noninvasive method for confirming parathyroid pathology in children preoperatively. Other reliable studies include 99mTc and sestamibi scans, which can accurately localized the pathology in 2 of 3 children.
The most common cause of Primary Hyperparathyroidism is a solitary adenoma (benign tumor) of one parathyroid gland. Less commnonly, parathyroid hyperplasia (all four glands enlarged) may be the result of a condition known as Multiple Endocrine Neoplasia (MEN). A family history of parathyroid disease or hypercalcemia is present in a significant portion of patients. A genetic evaluation is recommended for all patients and family members diagnosed with multigland hyperplasia but with no previous family history of MEN or familial non-MEN disease.
Secondary hyperparathyroidism occurs usually in cases of kidney failure or intestinal malabsorption of calcium. In these conditions, all four parathyroid glands secrete high levels of PTH. This can sometimes be treated with medicine, but may eventually require removal of the glands if too much calcium is resorbed from the bones and deposited in other tissues. Tertiary hyperparathyroidism is a persistent hyperfunction of the glands even after the kidney failure is treated successfully with medicines or kidney transplant.
Once the diagnosis of hyperparathyroidism is made, the abnormal parathyroid gland or glands should be surgically removed. The abnormal glands can be localized with ultrasound or sestamibi scan. During surgery, blood samples are tested to make sure the high level of PTH comes down after removal of the gland(s). If all glands are removed, then part of one may be reimplanted in a muscle to allow enough function to appropriately balance calcium levels. After surgery, the patient may need calcium and vitamin D supplements for awhile until the remaining gland(s) starts functioning. This complication rate for parathyroidectomy in children is comparable to the 3% permanent hypocalcemia usually sited in the literature for adults. The overall success rate for operative treatment of HPT in pediatric patients is excellent, and operative therapy has been shown to be more effective than medical therapy for infants and neonates.
REFERENCES
Principles and Practice of Pediatric Surgery, Oldham et al. 2005 Lippincott Williams and Wilkins, Philadelphia, PA
Primary Hyperparathyroidism in Pediatric Patients. Kollars et al. Pediatrics Vol. 115 No. 4, 974 -980
