Thyroid and Parathyroid

MEN patients to have more than four functioning glands, a thorough exploration and
a transcervical thymectomy should be a routine part of the operation. It is not
. uncommon for these patients to have five or six parathyroid glands
HYPERCALCEMIC CRISIS
Hypercalcemic crisis represents the life-threatening systemic condition brought on by
.( elevated serum calcium levels (generally 13.0 mg/dL or higher
Clinical Manifestations
Symptoms are varied and range from neuromuscular changes with mild fatigue and
irritability to coma. Signs of dehydration are prominent. Gastrointestinal
manifestations include anorexia, nausea, vomiting, and weight loss. Cardiac
dysrhythmias, most commonly secondary to a shortened Q-T interval, may occur and
can be lethal. Cancer cachexia may be evident in patients presenting with skeletal
metastases. A palpable neck mass in the face of hypercalcemic crisis is considered a
parathyroid carcinoma until proved otherwise. Therapy is initiated before attempting
. to differentiate the cause of hypercalcemia
The list for the differential diagnosis is theoretically long, with any cause of
hypercalcemia included, but in the vast majority (more than 90 percent) of cases it
. comes from advanced malignancy or primary hyperparathyroidism
Treatment
Intravenous saline resuscitation is started and advanced to achieve a diuresis of higher
than 100 mL/h. Dehydration is prominent with hypercalcemic crisis, and volume
resuscitation (often 4 to 5 L) is the cornerstone of therapy. Once the patient appears
adequately hydrated and urine output is more than 1 mL/kg/h, loop diuretics are given
to stimulate a natriuresis and subsequent calciuresis. Cardiac dysrhythmias typically
resolve with hydration and the subsequent decrease in the serum calcium level.
Should dysrhythmias persist or become symptomatic, they are treated with standard
agents for dysrhythmia. When hypercalcemia persists in the face of aggressive
resuscitation and diuresis, the addition of mithramycin, phosphate binders (e.g.,
pamidronate), vitamin D, estrogen, calcitonin, or steroids may be useful.
Hypercalcemia in patients with advanced malignancy and skeletal metastases can be
. difficult to normalize
Patients with hyperparathyroidism usually can be stabilized with simple hydration and
diuresis. Identification of a cervical mass on physical examination in the face of
hypercalcemic crisis foreshadows a diagnosis of parathyroid carcinoma. Vocal cord
function should be checked and the diagnosis of malignancy discussed with the
patient. Ultrasonography may be useful while resuscitation is under way, or in the rare
patient who is critically ill from persistent hypercalcemia. If a large adenoma is
identified, hypercalcemia can be resolved quickly with a focused exploration and
parathyroidectomy. With hemodynamic stability, regardless of the results of
ultrasonography, operative intervention is undertaken early in patients with primary
hyperparathyroidism. If the diagnosis of primary hyperparathyroidism is secure, even
in comatose patients or in those with hemodynamic instability despite volume
resuscitation, operative intervention should not be delayed. Postoperative transient
hypocalcemia is common, and frequent calcium assessment is prudent because of the
.
previous instability of these patients