Renal magnesium wasting in two families with autosomal dominant inheritance

Hypomagnesemia due to isolated renal magnesium loss was demonstrated in two unrelated families with autosomal dominant mode of inheritance. Magnesium infusions performed in two patients showed not only a reduced renal magnesium threshold but also a lowered renal tubular maximum for magnesium. All members of both families who presented with hypomagnesemia had also a lowered excretion of calcium in the urine, presumably as a consequence of increased reabsorption in Henle's loop.     

The Rigiflex TTS: A New Method to Dilate Benign Esophageal Stenosis

Abstract: This paper dicusses the use of esophageal dilatation with a Rigiflex TTS balloon. This method was used 45 times on 11 patients affected by anastomotic or a severe grade peptic esophageal stenosis. Fluoroscopic guidance was used in 36 procedures (80%) without effecting the mean duration of the treatment (12 minutes). The results were considered satisfactory when these goals had been achieved: a) dilatation of the stenosis over 15 mm; b) a dysphagia free-time of more than 6 months. A satisfactory result was achieved in 10 patients (90.9%), without deaths and major complications. 5 patients received 1 dilatation and the other 5 needed, 3-3-4-7–11 procedures respectively to obtain a satisfactory result. On these basis we consider that its great efficacy, security and tolerability depend on the following characteristics of the Rigiflex TTS balloon: 1) “radial” dilatation; 2) the possibility of introducing the balloon through the operative channel of the fiberscope; 3) direct visualization of the stenosis during dilatation. The following disadvantages with this method are: the absence of a tactile sensation of dilatation and the elevated cost of the instrument. We conclude that the Rigiflex TTS balloon is an important alternative to guide-wire techniques, especially for the treatment of severe esophageal strictures.     

Distinction between renal and nonrenal hematuria using immunoperoxidase staining of erythrocytes in urine for Tamm-Horsfall protein]

A recently described immunocytochemical staining method to distinguish renal from non-renal haematuria was adapted for use in the standard clinical chemical laboratory. The method is based on the observation that only in case of renal haematuria are erythrocytes in urine coated with so-called Tamm-Horsfall protein, originating from the renal tubuli. Erythrocytes in urine were stained using an indirect immunoperoxidase method, resulting in cells with dark-brown stained surfaces. The staining methods were validated with material from clinically diagnosed cases of haematuria of renal or non-renal origin and compared with scores of the number of dysmorphic erythrocytes, another method to distinguish renal from non-renal haematuria. In specimens of presumed strictly renal haematuria 86% (SD 8.7; n = 26) of the erythrocytes stained immunocytochemically. However, in specimens of haematuria originating from bleeding in the renal pelvis few cells stained (6%; SD 5.8; n = 4). In specimens of purely non-renal haematuria only 13% (SD 13.5; n = 21) stained. Immunocytochemical staining of erythrocytes permitted a much better distinction between renal and non-renal haematuria, with better sensitivity and specificity, than the inspection of erythrocyte morphology. We conclude that immunochemical staining of erythrocytes in urine is a valuable method for distinguishing renal and non-renal haematuria.     

Reference values for nucleosides and nucleobases in cerebrospinal fluid of children

Disturbances in the metabolism of purines and pyrimidines in neurologically affected patients can be reflected by aberrant concentrations of nucleosides and nucleobases in cerebrospinal fluid (CSF). However, normal values, especially for children at different ages, are lacking. We collected 1000 specimens of CSF from subjects ranging in age from newborn to 18 years, who were undergoing a diagnostic lumbar puncture for several clinical indications. Of these, 78 samples could be used retrospectively as a reference according to our criteria. The analyses were performed with a modified HPLC procedure. None of the substances shows age-dependency except uridine and uric acid. Uridine increases with age, and uric acid increases with age in boys older than 12 years.     

Anulus fibrosus in bulging intervertebral disks

In this investigation the association of radial tears of the anulus fibrosus and bulging of the intervertebral disk was studied. An index of disk bulging was measured in sagittal anatomic sections in 149 lumbar disks from 31 cadavers. The indexes of disk bulging were correlated with stages of disk development and the presence of an annular tear. The largest disk-bulging indexes were always associated with radial tears of the anulus. Eighty-four percent of the disks with radial tears had disk-bulging indexes greater than 2.5 mm. Most normal adult disks had an index of less than 2.5 mm. The results challenge the concept that the anulus fibrosus is intact in bulging disks, although ruptured in herniated disks.     

Evidence for intact V1-vasopressin receptors in congenital nephrogenic diabetes insipidus

The binding of tritium-labelled arginine vasopressin to human platelet vasopressin receptors was investigated in patients with congenital nephrogenic diabetes insipidus. Binding characteristics, that is receptor affinity and the maximum number of binding sites, were not significantly different from those found in normal control individuals. The findings confirm the concept of intact V₁ receptors in congenital nephrogenic diabetes insipidus. The defect in nephrogenic diabetes insipidus apparently only affects the cyclic adenosine monophosphate dependent V₂ receptors.