Maintenance of adequate hemodialysis access. Prevention of neointimal hyperplasia.

The maintenance of adequate hemodialysis vascular access is frequently complicated in the patient with polytetrafluoroethylene (PTFE) A-V hemodialysis grafts by venous anastomotic stenosis. This stenosis is caused by neointimal hyperplasia (NIH), a response to vascular injury. In this study, the authors prospectively analyzed the effect of a short-term regimen consisting of administration of two medications, heparin and low molecular weight dextran, on the development of NIH at the venous anastomosis in 79 patients with PTFE A-V hemodialysis grafts.

Nephrolithiasis in pregnancy.

Although the anatomical and physiological changes of normal pregnancy may predispose to kidney stone formation, it remains an uncommon occurrence. Correct diagnosis is often difficult. Ultrasonography has become the primary radiological diagnostic tool, with a limited excretory urogram only necessary in complicated cases.

Acute renal failure in pregnancy.

ARF is becoming an increasingly rare complication of pregnancy in industrialized countries because of a decrease in illicit abortions, improved prenatal care, and better management of maternal complications potentially leading to ARF. Early recognition of ARF with prompt therapy of reversible causes and rapid delivery in untreatable cases has led to more favorable outcomes for both gravida and fetus. Clinicians should be alert for entities unique to pregnancy, e.

Gestational hypercalciuria causes pathological urine calcium oxalate supersaturations.

Although normal pregnant women are more hypercalciuric than women with calcium oxalate nephrolithiasis (243 +/- 23 mg/day vs. 194 +/- 5 mg/day), pregnancy is not an established stone-forming state and pregnant women do not exhibit pathological crystalluria. One hypothesis to explain their lack of overt stone formation and pathological crystalluria is that pregnancy does not raise urine supersaturation with respect to stone forming salts such as calcium oxalate or calcium monohydrogen phosphate (brushite) to levels as high as in stone forming women.

Nephrolithiasis and gestation.

Although both anatomical and physiological changes in pregnancy may predispose to kidney stone formation, it still remains an uncommon occurrence. Correct diagnosis is often difficult. Ultrasound has become the primary diagnostic tool, and a limited study excretory urogram is only necessary for complicated cases.