Clinical and molecular characteristics of two Italian kindreds with hypoparathyroidism, deafness and renal dysplasia (HDR) syndrome.

PURPOSE: Hypoparathyroidism, deafness, and renal dysplasia (HDR) syndrome, also known as Barakat syndrome, is a rare autosomal dominant disease characterized by the triad of hypoparathyroidism, deafness, and renal abnormalities. The disorder is caused by the haploinsufficiency of the zinc finger transcription factor GATA3 and exhibits a great clinical variability with an age-dependent penetrance of each feature. We report two unrelated kindreds whose probands were referred to our outpatient clinic for further evaluation of hypoparathyroidism. METHODS: The proband of family 1, a 17-year-old boy, was referred for severe hypocalcemia (5.9 mg/dL) incidentally detected at routine blood tests. Abdomen ultrasound showed bilateral renal cysts. The audiometric evaluation revealed the presence of bilateral moderate hearing loss although the patient could communicate without any problem. Conversely, the proband of family 2, a 19-year-old man, had severe symptomatic hypocalcemia complicated by epileptic seizure at the age of 14 years; his past medical history was remarkable for right nephrectomy at the age of 4 months due to multicystic renal disease and bilateral hearing loss diagnosed at the age of 18 years. RESULTS: Based on clinical, biochemical, and radiologic data, HDR syndrome was suspected and genetic analysis of the GATA3 gene revealed the presence of two pathogenetic variants in exon 3, c.404dupC and c.431dupG, in the proband of family 1 and 2, respectively. CONCLUSION: HDR syndrome is a rare cause of hypoparathyroidism and must be excluded in all patients with apparently idiopathic hypoparathyroidism. A correct diagnosis is of great importance for early detection of other HDR-related features and genetic counseling.

Body fluid compartments in hypertension.

BACKGROUND AND OBJECTIVES: There is a correlation between the fluid and ionic homeostasis and blood pressure but it is not known if these body fluid changes represent the cause or rather the effect of the blood pressure rise. We have estimated the compartmental distribution of body fluids by means of the Bioimpedance Spectroscopy (BIS) analysis in a hypertensive cohort compared to control subjects. MATERIAL AND METHODS: We have enrolled 28 hypertensive patients (14 females, 14 males, mean age 47 +/- 5) and a sex- and age-matched control group of 37 healthy subjects (17 females and 20 males, mean age 45 +/- 8). They underwent anthropometric measurements, then extracellular (ECW) and intracellular water (ICW) were assessed using BIS. RESULTS: Both mean weight and BMI of hypertensive patients resulted significantly higher than of the control group (p < 0.05). We found higher ICW values in hypertensive compared to normotensive subjects. This difference was proportional to the difference of mean blood pressure values, reaching significance only as regards the stage II hypertensive subgroup (p < 0.03). DISCUSSION: Our data confirm that the blood pressure increases are associated to TBW, and caused mainly by ICW increases. The BIS, a simple, reliable, non invasive and cost effective methodical approach, estimating the distribution of body fluids, offers new possibility of the management of the hypertensive disease, to establish a more appropriate antihypertensive treatment. Moreover, the BIS, estimating the volume restoration of the different body compartments, may be helpful in evaluating the effectiveness of the pharmacological treatment.