The effect of oral contraceptives on the gonadotropin response to LHRH.

This study was designed to assess the effect of long-term treatment with three combined oral contraceptives (OC) on the gonadotropin response to LHRH. The release of LH and FSH after a single 50-microgram dose of LHRH was studied from Days 11 to 14 of treatment and Days 2 and 3 after discontinuation of the treatment. The responses were compared with controls during the luteal phase (Days 16 to 19) of the menstrual cycle. LH and FSH baseline levels and release after LHRH injection were markedly depressed in women on OC treatment. The patterns of gonadotropin response after LHRH, however, were similar to the responses during the luteal phase. Following discontinuation of OC treatment, the basal levels of LH and FSH and the response to LHRH continued to be depressed, with a further decrease in the FSH release. These results indicate that treatment with combined OC exert a significant depression on the release of gonadotropins.     

Renal osteodystrophy in nondialysed adolescents. Long-term treatment with 1alpha-hydroxycholecalciferol

The effects of small oral doses (1-2 microgram/day) of 1alpha-hydroxycholecalciferol, given for 1 to 2 years, have been examined in four nondialysed adolescents with chronic renal failure and bone disease. Treatment increased calcium retention and plasma calcium, and decreased plasma levels of alkaline phosphatase, hydroxyproline, and immunoreactive parathyroid hormone. X-ray abnormalities of bone regressed, and 2 patients underwent successful surgical correction of knock-knees; bone histology in these 2 was normal at the time of operation. 2 patients developed hypercalcaemia which promptly reversed when 1alpha-hydroxycholecalciferol was withdrawn. In one patient treatment was initially successful, but later there was biochemical, radiographic, and histological evidence of relapse. Long-term treatment of such patients with 1alpha-hydroxycholecalciferol may be effective and facilitate the surgical correction of deformities, but this is not invariable. Toxic effects are similar to those of vitamin D itself, but are more readily reversible.     

Biopterin derivatives in normal and phenylketonuric patients after oral loads of L-phenylalanine, L-tyrosine, and L-tryptophan

Plasma biopterin derivatives studied in 10 normal and 21 phenylketonuric children showed a significantly high concentration in the latter group. Biopterin derivatives correlated with plasma phenylalanine concentration, but in normal adults given an oral phenylalanine load the rate of increase with phenylalanine differed from that in phenylketonuric patients. A patient with hyperphenylalaninaemia, not due to phenylketonuria, had an abnormal biopterin derivatives response to phenylalanine distinct from that of patients with classical phenylketonuria. This may be a useful investigation to differentiate some variants of phenylketonuria.     

Current practice in dietary management of diabetic children. A transatlantic comparison

Dietary therapy practice in 18 British clinics for diabetic children is reviewed, and contrasted with Canadian and American practice. Values for dietary composition expressed as energy are presented for small groups of British and Canadian children. Fat is often the principal energy source in British diabetic children; protein intake is much higher in the Canadian. It is suggested that British practice might be improved by the adoption of a simple uniform exchange system. Reported differences in growth characteristics may reflect differences in protein intake.     

Decreased splenic enhancement on CT in traumatized hypotensive patients

Three patients with transient episodes of hypotension following blunt abdominal trauma incurred in motor vehicle accidents were examined by computed tomography within 6 hours of injury. The examinations were done using a contrast material injection technique that ordinarily leads to greater splenic than hepatic attenuation. None of the patients had splenic injury evident on autopsy, surgery, or clinical follow-up study (one case each), nor did they have other characteristic features of splenic infarction. However, in each case the spleen was less enhanced than the liver, leading to an erroneous impression in one patient that the splenic artery had been disrupted. Physiologic studies have shown that splenic perfusion decreases with sympathetic stimulation; this may have been the cause of the diminished enhancement. Decreased splenic enhancement should be interpreted cautiously in traumatized hypotensive patients.     

Arthrographic study of painful total hip arthroplasty: refined criteria

The criteria for a diagnosis of loosening or infection of hip arthroplasties on arthrographic study were further refined by a retrospective review of 178 arthrograms representing 170 patients. The 97 arthroplasties that were surgically evaluated form the basis of this report. With the refined criteria, subtraction arthrography had a sensitivity of 96% and specificity of 92% for demonstrating loosening of the femoral component and a sensitivity of 97% and a specificity of 68% for demonstrating loosening of the acetabular component. Pseudocapsule size and the presence of bursae were important factors influencing arthrographic interpretation. Arthrographic findings of pseudocapsule irregularity and the presence of nonbursal cavities were suggestive of infection but were not sensitive or specific. Laboratory evaluation of aspirated material was a more reliable predictor of infection, although its sensitivity was only 71%.     

Breast mass detection by US: a phantom study

Phantoms were used to compare imaging of various masses in the glandular region for two types of breasts. In one type, normal glandular tissue contains no fat clumps; in the other type, randomly distributed spherical fat clumps exist. The size distribution and number of fat clumps per unit volume in the phantoms represented those found in actual normal glandular tissue. For a 5-cm path length between the scanning window of the phantom and the centers of the masses, the presence of the fat clumps caused distortions and deviations of the beam, resulting in image distortion. This degradation was reduced when successive slabs of the material containing the fat clumps were removed. Image degradation appeared to be less severe when a 2.25 (rather than a 3.5) MHz transducer was used. The results show that the thickness of tissue containing fat clumps between the scanning transducer and a mass plays a role in the detectability of masses and diagnostic usefulness of the image of a breast. This suggests that imaging of the breast in the compressed configuration should be performed regardless of whether the freely suspended breast is imaged. Also, transducers of lower nominal frequency may have an important role in breast imaging.