Reversal of sleep apnea in uremia by dialysis.

Obstructive sleep apnea (OSA) is a common syndrome occurring in 1% to 4% of the population. While obesity is the most common predisposition to OSA, metabolic disorders have been associated with this syndrome. We describe a patient who presented with severe OSA while in an advanced untreated uremic state, which resolved following intensive dialysis. We speculate that the sleep disturbances, which are common in uremia, may be accounted for in some patients by OSA and may resolve with specific therapy for advanced renal failure.

Secondary focal segmental glomerulosclerosis in non-obese patients with increased muscle mass.

BACKGROUND: Secondary focal segmental glomerulosclerosis (FSGS) is a pattern of glomerular injury mediated by hyperfiltration and other adaptive structural-functional responses. We describe 3 non-obese patients with elevated body mass index (BMI) owing to increased muscle mass who had renal biopsy findings favoring a form of secondary FSGS. METHODS: Clinical and pathologic data were obtained on 3 patients with 1) renal biopsy findings of focal segmental and/or global glomerulosclerosis with glomerulomegaly; 2) BMI > or = 30; 3) body fat percentage < 20%; 4) "highly muscular" appearance, and 5) proteinuria > or = 1 g/d without nephrotic syndrome. 24-hour urine creatinine excretion was used to estimate lean body mass and percentage body fat. RESULTS: The 3 patients were males (age 38 - 48 years) employed in jobs requiring strenuous physical activity. BMIs ranged from 30.4 - 32.1 kg/m2 with body fat percentages of 12.9 - 16.8%. Creatinine clearances at time of biopsy ranged from 113 - 208 ml/min. Renal biopsies showed focal segmental and/or global glomerulosclerosis affecting a minority of glomeruli with glomerular hypertrophy and minimal (mean 15%) foot process effacement. Treatments included angiotensin-converting enzyme inhibitor, angiotensin II receptor blocker, or weight loss. Over a mean follow-up time of 24.3 months, serum creatinine remained stable and proteinuria decreased in all patients. CONCLUSIONS: Non-obese patients with increased BMI due to elevated muscle mass are at risk of developing a secondary form of FSGS that resembles obesity-related glomerulopathy.

The use of technetium-99m sulfur colloid in the detection of patent processus vaginalis in patients on continuous ambulatory peritoneal dialysis.

Continuous ambulatory peritoneal dialysis (CAPD) is commonly used in patients with renal failure as an alternative to hemodialysis. A not infrequent complication is scrotal swelling due to bowel or fluid passing through a patent processus vaginalis secondary to increased abdominal pressure. A radionuclide study using Tc-99m sulfur colloid is a safe and simple method to determine if this complication is present or may be used as a pre-CAPD screening procedure.

Use of gallium scanning in predicting resolution of Legionnaires' pneumonia.

The value of Ga-67 scanning to detect acute infectious lung disease has been described. We present a patient who apparently improved both clinically and radiographically after acute Legionnaires' pneumonia. Five months later a relapse developed. During his relapse the pulmonary uptake of Ga-67 and the appearance of chest x-rays were disparate. We suggest that pulmonary Ga-67 uptake may be a more sensitive indicator of the resolution of pneumonia than is chest radiography. Therapeutic success may be assumed when pulmonary Ga-67 uptake is absent.

The evaluation of iron status in hemodialysis patients.

Effective treatment of anemia in hemodialysis patients requires ongoing monitoring of iron status. The purpose of this study was to determine levels of commonly used iron indices predictive of iron deficiency in this population. Forty-seven patients with baseline serum ferritin levels < 600 ng/mL were treated with intravenous iron dextran (INFeD; Schein Pharmaceutical Inc., Florham Park, NJ), 1000 mg over ten hemodialysis treatments. Patients whose hematocrit value increased by 5% or who had a 10% decrease in their erythropoietin dose by 2 months were classified as having iron deficiency (N = 31; 66%). All other subjects were classified as having adequate iron (N = 16; 34%). There was no statistically significant difference in baseline serum ferritin, transferrin saturation, mean cell volume, mean cell hemoglobin content, or red cell distribution width between the two groups. Receiver operator curves demonstrated that none of the iron indices had a high level of utility (both sensitivity and specificity > 80%). Two tests had marginal utility, serum ferritin at a level of < 150 ng/mL, and transferrin saturation < 21%. It was concluded that because of the tests' marginal utility, they should only be interpreted in the context of the patient's underlying erythropoietin, responsiveness. In patients who are responsive to erythropoietin, a transferrin saturation value < 18% or serum ferritin level < 100 ng/mL should be used to indicate inadequate iron. When erythropoietin resistance is present, transferrin saturation of < 27% or serum ferritin < 300 ng/mL should be used to guide iron management.