Fludrocortisone treatment in a child with severe cerebral salt wasting

Hyponatremia is a common complication of intracranial disease or surgery. An evaluation should be undertaken to determine whether cerebral salt wasting (CSW) or inappropriate secretion of antidiuretic hormone is present as a cause. Since the treatment principles are completely different in the two pathological states, differential diagnosis is very important. CSW is defined as the renal loss of sodium leading to hyponatremia and decreased extracellular fluid volume. In the literature, it has been noted that mineralocorticoid administration can be useful in CSW cases. We herein present an 11-year-old boy who developed hyponatremic seizures after intracranial tumor resection. He was diagnosed with CSW on the basis of high urinary sodium excretion and increased urine output, together with signs and symptoms of dehydration. Despite intensive fluid and salt therapy, we were unable to decrease the urinary output. Therefore, fludrocortisone therapy was administered and his urinary output and sodium excretion were decreased and his serum sodium level was normalized. In conclusion, in addition to fluid and salt replacement, mineralocorticoid supplementation also seems to be a safe and effective treatment for CSW. Copyright (C) 2001 S. Karger AG, Basel

Iodine deficiency in Turkey

Turkey is an iodine deficiency area. The overall goitre prevalence is thought to be 30%, and most epidemiological studies give figures compatible with mild to moderate iodine deficiency. However, it is suspected that there are regions where iodine deficiency might be more severe than previously known. In this study the goitre prevalence and iodine status in a mountain village in Central Anatolia were investigated and the results compared to those of an urban area with mild iodine deficiency. Parameters of iodine status in the mountainous region showed severe iodine deficiency comparable to that in Central Africa. It seems that there are regions in Turkey where current programmes of salt iodization will be inadequate to correct the problem of iodine deficiency

A phenocopy of CAII deficiency: a novel genetic explanation for inherited infantile osteopetrosis with distal renal tubular acidosis

We report the molecular genetic investigation of two consanguineous kindreds where osteopetrosis and distal RTA (dRTA) were both manifest. One kindred harbours a novel homozygous frameshift alteration in CA2. In the other, CAII levels were normal despite a similar clinical picture, and we excluded defects in CA2. In this kindred, two separate recessive disorders are penetrant, each affecting a different, tissue specific subunit of the vacuolar proton pump (H(+)-ATPase), providing a highly unusual, novel genetic explanation for the coexistence of osteopetrosis and dRTA. The osteopetrosis is the result of a homozygous deletion in TCIRG1, which encodes an osteoclast specific isoform of subunit a of the H(+)-ATPase, while the dRTA is associated with a homozygous mutation in ATP6V1B1, encoding the kidney specific B1 subunit of H(+)-ATPase. This kindred is exceptional firstly because the coinheritance of two rare recessive disorders has created a phenocopy of CAII deficiency, and secondly because these disorders affect two different subunits of the H(+)-ATPase that have opposite effects on bone density, but which have only recently been determined to possess tissue specific isoforms

GROWTH-RESPONSE TO GROWTH HORMONE-RELEASING HORMONE(1-29)-NH2 COMPARED WITH GROWTH-HORMONE

To assess the growth-promoting effect of different doses of growth hormone-releasing hormone(1-29)-NH2 (GHRH(1-29)-NH2) in GH deficiency (GHD) of hypothalamic origin, 43 prepubertal children aged between 4.3 and 18.9 years (mean 10.4 +/- 2.9 years) were randomly assigned to three treatment regimens: low-dose GHRH(1-29)-NH2 (LD group; n = 15), high-dose GHRH(1-29)-NH2 (HD group; n = 12) and GH (GH group; n = 16). The LD group received GHRH(1-29)-NH2 at 30 mug/kg/day s.c. in three daily doses, the HD group received 60 mug/kg/day s.c. in three daily doses and the GH group received GH. 0.1 IU/kg/day s.c. once daily. All children were treated for a period of 6 months. Evaluation included anthropometry, bone age, intravenous and subcutaneous GHRH(1-29)-NH2 tests and determination of insulin-like growth factor I (IGF-I) levels. An increase in height velocity of 2 cm/year or more was observed in all except two children. Height velocity during treatment was lowest in the LD group, but comparable in the HD and GH groups. An increase in height SDS for bone age occurred only in the GH-treated group. GH responses to intravenous GHRH(1-29)-NH2 showed a priming effect of the LD GHRH(1-29)-NH2 treatment, while a decrease in response occurred in the GH-treated group. Following a subcutaneous test dose of one-third of the daily dose of GHRH(1-29)-NH2, GH levels remained unchanged in both the LD and HD groups. There was accumulation of GHRH immunoreactivity over time in the HD group, but there was no correlation between measured GHRH and GH levels. IGF-I levels increased in the HD and GH-treated groups. Antibodies to GHRH were detected in 54% and 58% of children in the LD and HD groups, respectively. None of these variables correlated with changes in height velocity. The results indicate that 6 months of GH and high-dose GHRH(1-29)-NH2 treatment have similar growth-promoting effects

J Med Genet

The rare bone thickening disease osteopetrosis occurs in various forms, one of which is accompanied by renal tubular acidosis (RTA), and is known as Guibaud-Vainsel syndrome or marble brain disease. Clinical manifestations of this autosomal recessive syndrome comprise increased bone density, growth failure, intracerebral calcification, facial dysmorphism, mental retardation, and conductive hearing impairment. The most common cause is carbonic anhydrase II (CAII) deficiency. Several different loss of function mutations in CA2, the gene encoding CAII, have been described. To date, there have been no exceptions to the finding of CAII deficiency in patients with coexistent osteopetrosis and RTA. Most often, the RTA is of mixed proximal and distal type, but kindreds are reported in which either distal or proximal RTA predominates. We report the molecular genetic investigation of two consanguineous kindreds where osteopetrosis and distal RTA (dRTA) were both manifest. One kindred harbours a novel homozygous frameshift alteration in CA2. In the other, CAII levels were normal despite a similar clinical picture, and we excluded defects in CA2. In this kindred, two separate recessive disorders are penetrant, each affecting a different, tissue specific subunit of the vacuolar proton pump (H+-ATPase), providing a highly unusual, novel genetic explanation for the coexistence of osteopetrosis and dRTA. The osteopetrosis is the result of a homozygous deletion in TCIRG1, which encodes an osteoclast specific isoform of subunit a of the H+-ATPase, while the dRTA is associated with a homozygous mutation in ATP6V1B1, encoding the kidney specific B1 subunit of H+-ATPase. This kindred is exceptional firstly because the coinheritance of two rare recessive disorders has created a phenocopy of CAII deficiency, and secondly because these disorders affect two different subunits of the H+-ATPase that have opposite effects on bone density, but which have only recently been determined to possess tissue specific isoforms