22q11 deletion: a multisystem disorder requiring multidisciplinary input.
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AIM: To draw up recommendations for the investigation and management of children with a microdeletion of chromosome 22q11. METHODS: A retrospective review of case notes from patients with a chromosome 22q11 microdeletion identified by cytogenetics laboratories of the south and west of Britain over a four year period. RESULTS: A total of 210 cases were identified. Age at diagnosis was 0-1 years (34%), 1-4 (17%), 5-17 (35%), and 18 years or more (13%). School age children were less likely to be investigated than infants: echocardiography in school age 86% v in infancy 97%, serum calcium 66% v 89%, renal ultrasound scan 38% v 42%, lymphocyte count 26% v 68%, parental karyotype 78% v 88%. The yield of investigations remained high throughout all age groups with 42% of school age children shown to have hypocalcaemia and 25% abnormal findings on renal ultrasound. CONCLUSIONS: 22q11 microdeletion is a multisystem disorder requiring a set of core investigations at diagnosis. We recommend an echocardiogram, renal ultrasound scan, lymphocyte count and function, serum calcium, and parental karyotype as a minimum. Genetic counselling and community paediatric input is helpful for most families. (+info)
Dilated cardiomyopathy due to endocrine dysfunction.
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Dilated cardiomyopathy can be idiopathic or be caused by many potentially treatable conditions. We report a complex case of peripartum heart failure associated with hypothyroidism and hypoparathyroidism. Myocardial biopsy suggested that hypothyroidism was the main cause for the dilated pattern, but hypocalcemia played a critical role in acute decompensation of heart failure during hospitalization. After a long and clinically complicated hospital stay, correction of hypothyroidism and hypocalcemia resulted in near-normal cardiac function. (+info)
Hypomagnesemia with increased metabolism of parathyroid hormone and reduced responsiveness to calcitropic hormones.
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A patient with severe hypomagnesemia due to chronic alcoholism is presented who repeatedly exhibited marked hypocalcemia with a dissociation between radioimmunoassay findings for mid region of parathyroid hormone (PTH-M) and immunoradiometric assay findings of serum intact PTH (PTH-intact). Serum PTH-M was moderately elevated whereas serum PTH-intact was in a low normal range every time when her serum magnesium (Mg) concentration was markedly reduced. There was also a marked reduction in serum osteocalcin concentration. Supplementation of Mg resulted in a sharp increase in serum PTH level with a rapid disappearance of the dissociation between the two immunoassays of PTH. Shortly after serum PTH and 1,25(OH)2D levels reached their peak, serum osteocalcin started to increase, and was elevated into a supranormal level with normalization of serum Ca concentration. Mg is thought to act as a mimic/antagonist of calcium (Ca), and high extracellular Ca is shown to cause an inhibition of secretion with a stimulation of degradation of PTH. Thus, these observations are consistent with the hypothesis that Mg deficiency causes an increase in the metabolism of PTH and a reduction in the secretion of bioactive intact PTH by increasing the sensitivity of parathyroid cells to Ca. In addition, the fact that hypocalcemia disappeared concomitant with a marked increase of serum osteocalcin from undetectable levels suggest that refractoriness of bone to calcitropic hormones is present which plays a significant role in the development of hypocalcemia under hypomagnesemia, and that serum osteocalcin can be a good marker for the assessment of the responsiveness of bone to calcitropic hormones in these patients. (+info)
Superiority of dynamic over static reference intervals for intact, midmolecule, and C-terminal parathyrin in evaluating calcemic disorders.
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We compared the clinical performance of assays of intact, C-terminal, and midmolecule parathyrin (PTH), when used with either a dynamic reference interval (based on the range of serum PTH concentrations observed in 35 healthy individuals during acute modifications of their blood calcium concentrations) or a gaussian (mean +/- 2 SD) interval derived from normocalcemic individuals. Dynamic intervals were substantially different from gaussian intervals, with half of the area delimited by the gaussian limits for calcium and intact PTH concentrations, and one-third for both C-terminal and mid-PTH assays, being outside the range of values observed during the dynamic tests. Use of the dynamic intervals increased the average clinical sensitivity of the three assays for detecting primary hyper- and hypoparathyroidism from 68% to 97% (and up to 100% for the intact and C-PTH assays). Even though only the intact PTH assay allowed complete separation between primary hyperparathyroid and nonparathyroidal hypercalcemic patients, the average proportion of patients correctly classified in this latter category was increased from 40% to 70% by the use of dynamic intervals. We conclude that gaussian reference intervals are largely responsible for the poor clinical sensitivity of many types of PTH immunoassays and that they should be replaced by dynamic reference intervals when evaluating calcemic disorders. (+info)
IDIOPATHIC STEATORRHEA PRESENTING WITH DIFFERENT MANIFESTATIONS IN SISTERS.
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Although it is well known that the incidence of idiopathic steatorrhea is much higher in relatives of patients with this disease than it is in the general population, there has been little comment on the variability of symptoms in familial cases. Two sisters with this disease are reported. One presented with a relatively acute history of diarrhea, weight loss, fatigue and peripheral edema and was found to have a normal hemoglobin, hypocalcemia and a markedly decreased prothrombin activity. Her elder sister tended to constipation and had a 10-year history of refractory iron-deficiency anemia. The diagnosis was confirmed in both by peroral jejunal biopsy. (+info)
STUDIES ON THE SYNDROME OF FAT EMBOLIZATION.
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Three patients, all of whom were well-muscled young adult males who had suffered fractures of long bones, were studied by means of measurement of ventilatory function and arterial blood gases. They had degrees of mental change varying from mild confusion to stupor. Anemia, hypocalcemia, skin petechiae and radiologic pulmonary infiltrates were demonstrated in all three.In the absence of any clinical cyanosis, profound arterial O(2) desaturation was demonstrated in all. Physiologic studies indicated that the desaturation was the result of a diffusion defect early in the course of the syndrome and later from venous admixture. The lungs were stiff and the work of breathing was increased. The anemia appeared to be hemolytic in type.It is suggested that anemia, hypocalcemia and arterial O(2) desaturation may contribute significantly to the cerebral symptomatology associated with the syndrome of fat embolization. (+info)
WATERY DIARRHOEA AND AN ISLET CELL TUMOUR.
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It is suggested that there are two hormonal syndromes associated with noninsulin-secreting islet cell tumours and this case is an example of the non-gastrin-secreting type with watery diarrhoea and hypokalaemia. The patient had histamine-fast achlorhydria and a normal gastric biopsy and no gastrin was recovered from the tumour tissue. The watery diarrhoea was isosmotic with plasma and was increased by an intravenous saline load. There was a dramatic response to steroids. (+info)
Hypocalcemia and pregnancy-induced hypertension produced by maternal fasting.
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During pregnancy, maternal calcium needs increase as a result of increasing calcium requirements for fetal bone development. These needs have to be completely supplied by the mother via placental transfer. Several studies link low serum ionized calcium concentrations with the development of hypertension and pregnancy-induced hypertension. We hypothesized that maternal hypocalcemia would develop concomitantly with the development of hypertension in sheep that were fasted in late gestation. Sixteen instrumented ewes were used in the present study. After a 2-day baseline period, food was withdrawn from 10 animals in the experimental group (group 2) for 3 days, whereas the remaining six were allowed to eat and drink normally (group 1). Blood pressure, uteroplacental blood flow, and heart rate were monitored daily. Fasted animals were given deionized water (calcium free) to drink, whereas control animals were given tap water containing 32.9 mg/l calcium concentration. Based on the analysis of the ionized calcium concentration response to fasting, group 2 animals were placed in one of two groups: hypocalcemia did not develop in group 2a, whereas in group 2b the ionized calcium concentration decreased 27% (from 1.09 +/- 0.07 to 0.80 +/- 0.06 mM, p = 0.01) by the third day of fasting. Group 2b responded with a 16% elevation in maternal blood pressure (p = 0.01) and a 43% reduction in uteroplacental blood flow. Furthermore, a positive correlation was found between maternal and fetal blood ionized calcium concentrations (r = 0.860).(ABSTRACT TRUNCATED AT 250 WORDS) (+info)