Gastric emptying in patients with chronic renal failure on continuous ambulatory peritoneal dialysis.

Radionuclide gastric emptying studies were carried out on 20 patients with end-stage renal failure (ESRF) undergoing continuous ambulatory peritoneal dialysis (CAPD). Nine of the patients had diabetes mellitus. Eight normal volunteers were also studied to establish normal ranges. Solid and liquid emptying patterns were investigated simultaneously using a meal made up of a solid phase labelled with 99mTechnetium and a liquid phase labelled with 111Indium. The solid emptying fitted a model with a lag phase followed by a linear emptying phase and the liquid emptying fitted a single exponential. Nine of the 20 patients (four diabetic, five non-diabetic) were found to have delayed solid emptying, and four of these (two diabetic, two non-diabetic) also had delayed liquid emptying. No correlation was found between any of the parameters studied and the clinical symptoms of the patients. It is concluded that almost half of the patients studied had abnormal gastric emptying, but that many of these did not suffer from severe symptoms.

Misinterpretation of the upper parathyroid adenoma on thallium-201/technetium-99m subtraction scintigraphy.

Pre-operative thallium-technetium subtraction scintigraphy of 50 patients with primary hyperparathyroidism, which was subsequently proven on histology to be due to an adenoma, was compared with operative findings. Six scans were negative and seven uninterpretable. Of the remaining 37 patients, 34 had correct scan prediction of the anatomical locations of the adenomas. On examination of the origins of the adenomas, all six scintigraphic predictions of upper adenomas corresponded to tumours arising from the upper gland found at operation. Of the 25 lower predictions, there was one false positive and 16 were correct, i.e. of lower gland origin, but eight were found to originate from the upper gland. This misinterpretation is though to be due to the prolapse of an adenoma arising from the upper gland towards the lower pole of the thyroid, thereby mimicking a lower lesion on the scan.

Endocytosis of cationized horseradish peroxidase by glomerular epithelial cells is reduced in puromycin glomerulopathy.

Rats were treated with a single intravenous injection of aminonucleoside of puromycin and were sacrificed between 1 and 21 days after injection. The conjugate of horseradish peroxidase with a poly-L-lysine (HRP.PL) was used to reveal endocytotic activity in glomerular epithelial cells (GEC). This conjugate was injected intravenously 2 h before each sacrifice. Renal tissue was taken and treated cytochemically with a conventional DAB technique and observed by light and electron microscopy. The assessment of endocytosis by glomerular epithelial cells was performed on 1-micron sections by counting HRP.PL grains in the GEC and expressing this in terms of the area of glomerulus examined. The results were compared to those found in normal rats. Our results show that GEC endocytotic function was reduced during the whole period of the experiment. It fell quickly from 1 day after puromycin injection and reached the most marked reduction on the 4th day, preceding the peak of proteinuria which was between 7 and 12 days. From the 5th day onward the endocytotic function gradually recovered, but was still abnormal at the end of the experiment.

Isotope lymphography: a new method of investigating the role of the lymphatics in chronic limb oedema.

A method of investigating the lymphatic system by radionuclide imaging in patients with chronic lower limb oedema is described. The clearance of 99mTc rhenium sulphur colloid from the interdigital space of 55 limbs and its appearance in the ilio-inguinal lymph nodes 30 min, 1, 2 and 3 h later has been measured using a gamma camera in 34 limbs (26 patients) with the clinical and radiological features of primary lymphoedema, 10 limbs (8 patients) with venous oedema and 12 control limbs (6 volunteers). On visual interpretation the sensitivity of this technique in diagnosing lymphoedema was 97 per cent and its specificity 100 per cent, while it clearly differentiated between lymphoedema and venous oedema. Estimation of the percentage uptake of the colloid in the ilio-inguinal lymph nodes at 1/2, 1, 2 and 3 h showed a markedly decreased lymph flow in the 34 lymphoedematous limbs and an increased flow in the 10 limbs with venous oedema. The results suggest that this technique can be used as a simple diagnostic outpatient technique in the investigation of chronic limb oedema.

Assessment of pulmonary ventilation scans using xenon-127 in the diagnosis of pulmonary embolism.

Pulmonary ventilation scans using 127Xe were compared with scans using 133Xe in the diagnosis of pulmonary embolism. A perfusion scan using 99mTc -microspheres and ventilation scans with each of the xenon isotopes were performed on 44 patients referred for lung scanning to confirm or exclude a suspected clinical diagnosis of pulmonary embolism. No significant difference was found in the frequency of diagnosis of pulmonary embolism when comparing each of the ventilation scans with the corresponding perfusion scan. For reasons discussed, 127Xe may be more useful than 133Xe for pulmonary ventilation scanning.

Location of parathyroid adenomas by thallium-201 and technetium-99m subtraction scanning.

Solitary parathyroid adenomas were correctly located before surgery in 20 out of 21 cases by using 201mT1 and 99mTc in a subtraction technique. The technique was not useful in identifying hyperplastic parathyroid glands. The technique is recommended as a useful procedure before surgery for primary hyperparathyroidism.

Effect of intravenous dextran 70 and pneumatic leg compression on incidence of postoperative pulmonary embolism.

The incidence of pulmonary embolism and deep vein thrombosis was measured in 50 matched pairs of patients undergoing common surgical procedures with preoperative and postoperative ventilation-perfusion lung scans and the fibrinogen uptake test. One patient in each pair was treated with intravenous dextran 70 and pneumatic leggings. The incidence of pulmonary embolism among the treated patients was significantly reduced from 24% to 8%, but the incidence of deep vein thrombosis was not significantly reduced (34% to 24%).