In Bartter syndrome and Gitelman syndrome, a hereditary defect of the kidney tubules causes the kidneys to excrete excessive amounts of electrolytes (potassium, sodium, and chloride), resulting in growth, electrolyte, and sometimes nerve and muscle abnormalities.
These syndromes are caused by defective genes.
Symptoms include excessive urine production, mild dehydration, and low blood pressure.
Diagnosis is made by measuring electrolyte levels in the blood and urine and possibly by genetic testing.
All people are given supplements of sodium, potassium, and magnesium, and people who have Bartter syndrome are also given nonsteroidal anti-inflammatory drugs (NSAIDs).
The Nephrons, Glomeruli, and T...
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Bartter syndrome and Gitelman syndrome are hereditary and are usually caused by a recessive gene (see figure Non–X-Linked Recessive Disorders). Thus, a person with Bartter syndrome or Gitelman syndrome has usually inherited 2 recessive genes for the disorder, 1 from each parent. Because 2 genes are needed when a recessive gene is involved, the parents are carriers of the gene but do not have the syndrome. However, siblings of children with the disorder might have it. Although both are rare, Gitelman syndrome is more common than Bartter syndrome.
In Bartter syndrome and Gitelman syndrome, the kidneys cannot reabsorb salt (sodium chloride) normally from the kidney tubule. Thus, the kidneys excrete excessive amounts of the electrolytes sodium and chloride in the urine. The loss of sodium and chloride leads to excessive urine production and thus mild dehydration.
Mild dehydration causes the body to produce more of the enzyme renin and the hormone aldosterone, which help regulate blood pressure. The increase in aldosterone increases potassium and acid secretion in the kidneys, leading to low blood potassium (hypokalemia) and loss of acids in the blood that causes blood pH to be alkaline (a disorder called metabolic alkalosis). Although the tubules are affected in both syndromes, the kidneys are otherwise unaffected and filter out waste products normally.
Organs of the Urinary Tract
The main differences between the 2 syndromes are
The genes that are involved
The part of the tubule that is affected
The age at which symptoms begin
