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Jugular venous catheters (JVC) provide rapid, vascular access for both emergency and maintenance hemodialysis in both acute and end-stage renal disease. Clotting and occlusion of JVC is a common problem necessitating alternate vascular access. Urokinase will declot 80-90% of central venous catheters; however, recurrence of catheter occlusion is frequent. We successfully employed a guide wire insertion technique to salvage occluded JVC after failed urokinase infusion. In 24 patients JVCs, inserted for either temporary or permanent vascular access, clotted within 6-55 days of initiating hemodialysis. Urokinase (5,000 IU) instilled into both arterial and venous limbs of the catheter had been unsuccessful in restoring patency. In these patients, we inserted a soft-tipped guide wire into both lumina. In 21 of 24 patients (87.5%), guide wire insertion opened the occluded JVC, permitting immediate initiation of hemodialysis. We conclude that for clotted JVC unresponsive to urokinase infusion, guide wire insertion can salvage most catheters thereby facilitating hemodialysis.

We prospectively followed the course of eye disease in patients with diabetic end-stage nephropathy from the time of initial referral by the renal unit. A total of 31 patients (62 eyes)--9 of whom had functioning renal transplants and 22 of whom were on maintenance dialysis--were consecutively evaluated for 6-24 months (mean follow-up of 18 months). Visual acuity and diabetic retinopathy stabilized or improved in all 18 eyes of the transplant patients and in 41 of 44 (93%) eyes of the dialysis patients. When first evaluated, economically useful vision (20/200 or better) was present in 11 of 18 (61%) eyes in the transplant group and in 25 of 44 (57%) eyes in the dialysis group. At the most recent evaluation, economically useful vision was present in 13 of 18 eyes (72%) in the transplant group versus 28 of 44 eyes (64%) in the dialysis group. Ambulatory vision (counting fingers or better) was present in 15 of 18 eyes (83%) in the transplant group versus 37 of 44 eyes (84%) in the dialysis group.

Tuberculosis was diagnosed in eight patients undergoing maintenance hemodialysis and occurred with an incidence 10 times that of the general population. Dialysis-associated tuberculosis is characterized by intermittent fever, anorexia, weight loss and hepatomegaly. Ascites was present in 50 per cent of the patients. A recently converted positive tuberculin skin test was observed in five of eight patients. Tuberculosis was extrapulmonary in seven of eight cases and consequently the diagnosis was frequently delayed. Over-all mortality was 37.5 per cent and correlated with the duration of symptoms prior to initiation of therapy. A trial of antituberculous therapy is warranted in patients undergoing dialysis in whom fever of unknown origin, anorexia, weight loss and/or hepatomegaly develop particularly in areas endemic for tuberculosis.

Low concentrations (10-5 to 10-8 M) of 2-mercaptoethanol (2-ME) greatly enhance the proliferation of allogeneic cells in the rat mixed lymphocyte culture (MLC). Studies were undertaken to determine the mode of action of 2-ME. MLC proliferation can occur in the absence of serum proteins (fetal calf serum, FCS) only if 2-ME is present; however, a synergistic effect is present with FCS plus 2-ME, with a 3-fold increase in 3HTdR incorporation with FCS concentrations as low as 0.1%. Kinetic studies show no shift in the peak of proliferation (92 hr) when comparing cultures with and without 2-ME; however, 2-ME-supplemented cultures have significant 3HTdR uptake at 24 hr, and the peak amount of uptake at 92 hr is two to four times higher. Delayed addition of 2-ME until 92 and 166 hr produces a further increase in 3HTdR uptake, indicating that the entire effect is not expressed at the time of allogeneic recognition. L-ascorbic acid, another reducing agent which lacks sulfhydryl groups, elicits a much lower effect on DNA synthesis than does 2-ME. The cytotoxicity of cells harvested from MLC supplemented with 2-ME is increased without loss of target specificity, whereas the same concentration of 2-ME has no direct effect upon the cytotoxicity assay except at higher concentrations where 2-ME suppresses cytotoxicity.

Twenty-nine diabetic renal failure patients suffered a psychosocial crisis at the time when chronic dialysis or renal transplantation was required. These patients could be classified into groups as to the impact of the crisis in terms of participation in life-support therapy. Group 1 consisted of potentially lethal mechanism (9 patients): discontinued dialysis (5); refused to start dialysis (3); overt act to cause personal harm (1). Group 2 contained probably nonlethal mechanism (11 patients): threatened to discontinue dialysis or to never start dialysis if not given a chance for a transplant (5); threatened to discontinue dialysis or to never start dialysis (5); threatened to cause personal harm (1). Group 3 consisted of a combination of mechanisms (9 patients): with drug abuse (4); without drug abuse (5). Important similarities between the groups were easier to document than were subtle differences in the kinds of options in family and employment relationships; in the degree of objective and subjective handicap due to impaired vision; in the level of expectation and/or disappointment following renal transplantation; and in the capacity to cope with changing personal relationships produced by the complications of diabetes.

Hemodialysis is remarkably safe. Whether it is performed by professionals in a hospital or clinic or by the patient at home, the risk of death due to technical failure or human error in a single dialysis is only one in 76,138.1 Over a 10-year course of maintenance hemodialysis, the risk of accidental dialysis-related death is 2 per cent. This low level of risk is attributable in large part to technical advances that monitor the extracorporeal circuit, and interrupt blood flow in the event of air or blood leaks, high or low dialysate temperature, or incorrect mixing of the dialysate. Formerly . . .

BTG levels are significantly elevated in patients on chronic hemodialysis. The increased levels are not due to turbulent flow within the vascular access, but may be due to platelet aggregation within the hemodialyzer during the first hour of dialysis. This effect is observed with the Travenol CF series hollow fiber (cuprophane) but not the Cordis-dow artificial kidney (regenerated cellulose).

Beta-thromboglobulin (BTG), a platelet-specific protein released on platelet aggregation, was measured in 13 patients with clinical and biochemical evidence of the nephrotic syndrome. All 13 patients had increased concentrations of BTG compared to both 10 normal controls and to 12 non-nephrotic azotemic patients (p < 0.001). In five patients with the nephrotic syndrome in remission, the BTG levels returned to normal. These results support the contention that the nephrotic syndrome is associated with a state of hypercoagulability and suggest that increased platelet aggregation may be the primary underlying mechanism.

In Reply.— Whether or not hypertension and an elevated calcium-phosphate product are truly independent risk factors for cardiovascular disease in hemodialysis patients is a point fairly made. It is apparent that patients who are hypertensive are also more likely to have an elevated calcium-phosphate product, because they are noncompliant. That these factors are otherwise connected is unlikely. Even if hypertension in azotemic patients is controlled by drug therapy, failure to take unpalatable and constipating phosphate binders could still permit a sustained elevated product and metastatic calcification. When present together in the same patient, the negative effect on the cardiovascular system may be synergistic. Related to hypertension or not, an elevated calcium-phosphate product is certainly abnormal, and the lack of any statistical correlation with pathological damage should not preempt vigorous attempts at controlling this abnormality or any others when nontoxic therapy is available. Nephrologists are aware that the control of these