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(hī″pĕr-păr′ă-sī″tĭzm) A condition in which a parasite lives in or upon another parasite.


(hī″pĕr-par″ă-thī′royd-ĭzm) [hyper- + parathyroid + -ism] A condition caused by excessive levels of parathyroid hormone in the body. SEE: hypercalcemia; parathyroid glands; osteitis fibrosa cystica.

 INCIDENCE: Primary hyperparathyroidism is found in about 21 people per 100,000. Most patients with hyperparathyroidism are older women.

 CAUSES: Hyperparathyroidism is usually caused by an adenoma (benign tumor) of the parathyroid glands (primary hyperparathyroidism). Occasionally it occurs secondary to renal failure or other systemic illnesses. About 90% of the time, a single parathyroid adenoma is the cause. In about 10% of patients, generalized hyperplasia is found in all four parathyroid glands.

 SYMPTOMS AND SIGNS: Hyperparathyroidism is the most common cause of hypercalcemia, which can lead to central nervous system, musculoskeletal, metabolic, gastrointestinal, and cardiovascular problems when the concentration of calcium in the blood rises to very high levels (>11 mg/dL). Common consequences of excess parathyroid hormone include symptomatic or unnoticed hypercalcemia, hypophosphatemia, hyperchlorhydria, kidney stone formation, and bone resorption.

PATIENT CARE: Mild hyperparathyroidism may initially be managed expectantly without harm to the patient. Severe primary hyperparathyroidism may require surgical removal of the parathyroid gland or glands to prevent potential complications of hyperparathyroidism, including kidney stone disease, degeneration of bone, neuromuscular and neuropsychiatric illnesses, and pancreatitis. In some cancer patients, malignant tumors release a parathyroid-like hormone with hypercalcemia, which mimics hyperparathyroidism.

primary h. Hyperparathyroidism caused by either a single parathyroid adenoma or four-gland parathyroid hyperplasia. It typically causes hypercalcemia.

secondary h. Excessive levels of parathyroid hormone (PTH) released in response to a low serum calcium, or a high serum phosphate level. It may be due to vitamin D deficiency or chronic kidney disease.


(hī″pĕr-păth′ē-ă) [″ + pathos, disease, suffering] Hypersensitivity to sensory stimuli. Includes hyperesthesia, allodynia, and hyperalgesia.


(hī″pĕr-fā′jē-ă) [″ + Gr.

phagein, to eat] Eating more food than is required; gluttony or binge eating.


(hī″pĕr-fā′zh(ē-)ā) [hyper- + -phasia] 1. An abnormal desire to talk. 2. A misspelling for hyperplasia, esp. in foreign journals written in English. SEE: hyperplasia.


(hī″pĕr-fĕn″ĭl-ăl″ă-nĭ-nē′mē-ă) An increased amount of phenylalanine in the blood. SEE: phenylketonuria.


(hī″pĕr-fōr′ē-ă) [hyper- + -phoria] A tendency of one eye to turn upward. SYN: anophoria; anopsia (1).


(hī″pĕr-fŏs″fă-tă-sē′mē-ă) Increased alkaline phosphatase in the blood.


(hī″pĕr-fōs″fă-tē′mē-ă) [″ + L. phosphas...

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