Barakat syndrome or "Hypoparathyroidism, Sensorineural Deafness, Renal Disease" syndrome or HDR syndrome is a rare condition characterized by deafness, kidney disease and insufficiency parathyroid hormone production.
The list of signs and symptoms mentioned in various sources for Barakat syndrome includes the 11 symptoms listed below:
- Kidney failure
- Dry skin
- Coarse skin
- Muscle spasm
- Low blood calcium
Hypoparathyroidism may be acute or chronic and is classified as idiopathic or acquired. The acquired form may also be reversible. Idiopathic hypoparathyroidism may result from an autoimmune genetic disorder or the congenital absence of the parathyroid glands. Acquired hypoparathyroidism commonly results from accidental removal of or injury to one or more parathyroid glands during thyroidectomy or other neck surgery; rarely it results from massive thyroid irradiation. It may also result from ischemic infarction of the parathyroids during surgery or from hemochromatosis, sarcoidosis, amyloidosis, tuberculosis, neoplasms, or trauma. An acquired, reversible hypoparathyroidism may result from hypomagnesemia-induced impairment of hormone synthesis, from suppression of normal gland function due to hypercalcemia, or from delayed maturation of parathyroid function. PTH isn’t regulated by the pituitary or hypothalamus. It normally maintains blood calcium levels by increasing bone resorption and GI absorption of calcium. It also maintains an inverse relationship between serum calcium and phosphate levels by inhibiting phosphate reabsorption in the renal tubules. Abnormal PTH production disrupts this balance. The incidence is 4 out of 100,000 people. Incidence of the idiopathic and reversible forms is highest in children; that of the irreversible acquired form, in older patients who have undergone surgery for hyperthyroidism or other head and neck conditions
Audiometry and caloric testing or electronystagmography should be done in almost all cases in which the ear examination is normal. It is probably wise to consult an otolaryngologist at this point. Tympanography will be helpful in diagnosing subtle cases of serous otitis media. X-rays of the mastoids, petrous bones, and internal auditory canal should be done for chronic otitis media, cholesteatoma, and acoustic neuroma. If an acoustic neuroma is suspected, however, an MRI of the brain and auditory canals must be done. If basilar artery insufficiency is suspected, four-vessel cerebral angiography should be done. Magnetic resonance angiography is an excellent noninvasive alternative for diagnosing vertebral-basilar artery disease . If multiple sclerosis is suspected, MRI of the brain, BSEP and VEP studies, and a spinal tap for spinal fluid analysis may be done. Rather than perform these tests, the most cost-effective approach would be to refer the patient to a neurologist if other focal neurologic findings are evident.
Because calcium absorption from the small intestine requires the presence of vitamin D, treatment includes vitamin D and calcium supplements. Therapy is usually lifelong, except for the reversible form of the disease. If the patient can’t tolerate the pure form of vitamin D, alternatives include dihydrotachysterol, if hepatic and renal function is adequate, and calcitriol, if it’s severely compromised. In patients with preexisting hypomagnesemia, this condition must be corrected to treat the resulting hypocalcemia. A high-calcium, low-phosphorous diet is recommended. Acute life-threatening tetany requires immediate I.V. administration of calcium to raise serum calcium levels. The patient who’s awake and able to cooperate can help raise serum calcium levels by breathing into a paper bag and then inhaling his own carbon dioxide; this produces hypoventilation and mild respiratory acidosis. Sedatives and anticonvulsants may control spasms until calcium levels rise. Chronic tetany requires maintenance therapy with oral calcium and vitamin D supplements.