Bartter syndromes are defined as a family of inherited recessive autosomal heterogeneous renal tubular disorders, or tubulopathies. All disease variants follow autosomal recessive inheritance and share the following characteristic clinical features: renal salt wasting, hypokalemic metabolic alkalosis, normotensive hyperreninemic hyperaldosteronism, and hyperplasia of the juxtaglomerular apparatus.
Bartter syndrome type 3 presents with sequeale of pronounced hypokalemia and marked salt loss resulting in muscle weakness and volume contraction during the first years of life. Nephrocalcinosis is an uncommon finding, and investigation of renal concentrating ability is impaired to a lesser extent than in other variants of Bartter syndrome. Among other features, subnormal response to angiotensin II infusion and a pitressin concentration defect with mental and physical growth delay are common.
Abdel-al (1999) analyzed the prevalence and incidence of Bartter syndrome in Kuwait. Bartter's syndrome was diagnosed in 13 Kuwaiti children over a 14 year period (1981-1995) with the estimated incidence of 1.7/100,000 live births. The mean age at diagnosis was 9.3 months (range 2-32 months). There were five males and eight females (ratio 1:1.6). Both consanguinity and familial history among the patients were high (69 and 54%, respectively). All patients had hypokalemia, hypochloremia with metabolic alkalosis, hyperreninemia and were normotensive. Eleven patients (85%) had growth failure, two had nephrocalcinosis (15%) and one had renal failure. All patients were treated with supplemental potassium, an aldosterone antagonist (spironolactone) and a prostaglandin synthetase inhibitor (indomethacin or aspirin) sequentially. Significant catch-up of growth (four patients) and increases in serum potassium (eight patients) were recorded after administration of indomethacin therapy. One patient died of severe pneumonia with respiratory failure from hypokalemic myopathy.
[See also: Syria > El-Kishawi et al., 2005].
Zelikovic et al. (2003) examined the clinical, biochemical and genetic characteristics of a very large inbred Bedouin kindred in the lower Galilee with hereditary hypokalemic tubulopathy. The family has lived in the same area for more than two centuries. The pattern of inheritance of the disease in the family is compatible with an autosomal recessive trait. Twelve family members affected with hypokalemic tubulopathy, as well as 26 close relatives were clinically and biochemically evaluated. Evaluation of affected family members (age range 3 to 36 years) revealed phenotypic features of both Gitelman syndrome and classic Bartter syndrome. Features typical of classic Bartter syndrome included early age of presentation (<1 year) in 3 (25%), polyuria/dehydration in 4 (33%), growth retardation in 3 (25%), hypercalciuria (urinary calcium/creatinine mmol/mmoverline>0.55) in 4 (33%) and nephrolithiasis in 1 (8%).
El Aun et al. (1997) described a 2-year old girl who presented with polyuria and polydypsia. She was born pre-term at 36 weeks, with a birth weight of 2 Kg. She continued to develop normally, but remained underweight. At presentation, her weight was found to be under the 5th centile for her age. There were no other systemic abnormalities. Laboratory analysis revealed low specific gravity and osmolality of urine, and increased urinary excretion of calcium and potassium. The nephrocalcinosis was compatible with the diagnosis of Bartter's Syndrome. She was started on Acetylsalysalic aid before being switched to switched to Ibuprofen, and showed a very good response, with improvement in all parameters. There was no family history of a similar disease.
Malik et al. (1997) evaluated the parents and siblings of a Bartter syndrome patient for renal tubular function. The father and all 9 siblings of the patient had biochemical features of Bartter syndrome. His mother, a first cousin of his father, had hypokalemia and hyperkaluria but no other features of Bartter syndrome and could have been a 'carrier'. The mother and all 9 siblings were asymptomatic. Including the patient, hypomagnesemia was present in 8 of 12 family members. Therapy with a combination of potassium chloride and magnesium increased the serum potassium and magnesium levels to within normal limits. Malik et al. (1997) indicated that the presence of one affected parent and involvement of all siblings of the patient raise the possibility of an autosomal dominant inheritance in their family.
El-Kishawi et al. (2005) reported a pair of dizygotic twins suffering from neonatal Bartter syndrome with abnormal onset of early hyperkalemia who presented at Farwaniya Hospital in Kuwait. Both subjects, a boy and a girl, were born at 25 weeks gestation to consanguineous first degree cousins from Syria with five healthy children. The subjects had a birth weight of 900g and 600g, respectively. The boy passed away at an age of 5 days after experiencing severe hyperkalemia and the girl lived but suffered from developmental retardation and failure to thrive. El-Kishawi et al. (2005) suggested that these two cases were the first to be reported from Kuwait.
[El-Kishawi A, Soni A, Al-Saleh Q. Neonatal Bartter syndrome with early hyperkalemia: an unusual presentation in twins. Kuwait Medical Journal 2005, 37 (2): 130-2.]
Abou-Chaaban et al. (1997) studied the pattern of pediatric renal diseases among children in the Dubai Emirate during the period from 1991 to 1996. In this period, a total of 712 pediatric patients, including 230 nationals of the United Arab Emirates, were seen with various renal problems. In their study, Abou-Chaaban et al. (1997) observed two cases of Bartter's syndrome among nationals of the United Arab Emirates.