Acute nonhemodynamic pulmonary edema with nifedipine in primary pulmonary hypertension.

A 34-year-old man with primary pulmonary hypertension developed acute nonhemodynamic pulmonary edema after a loading dose of nifedipine. Changes of the vascular permeability induced by the drug acting on the arteriolar wall of the capillary system could be an explanation.

Impairment of phagocyte oxidative metabolism in hemodialyzed patients with iron overload.

In order to study the influence of iron overload on the polymorphonuclear leucocyte (PMN) metabolism of patients on chronic hemodialysis, generation of superoxide anion (O2-) by PMN in whole blood was compared in two groups of hemodialyzed patients: group A consisted of twenty-one individuals with serum ferritin levels above 1000 ng/ml and group B of nineteen individuals with serum ferritin levels below 1000 ng/ml. Whereas basal production of O2- was similar in the two groups (6.3 +/- 4.6 vs 11.5 +/- 8.3 nmoles O2- 10(6) granulocytes-1 15 min-1) (mean +/- s.e.m.), PMN response to opsonized zymosan was significantly lower in group A as compared with group B (86.5 +/- 6.3 vs 120.4 +/- 8.2 nmoles O2- 10(6) granulocytes-1 15 min-1) (p less than 0.01). Superoxide anion generation induced by the dialysis procedure was reduced in eight patients from group A (89.2 +/- 32.1) as compared with eight patients from group B (374.3 +/- 100.0 nmoles O2- 10(6) granulocytes-1 15 min-1) (p less than 0.05). These data suggest that iron overload may be involved in the impairment of neutrophil phagocytosis in patients on chronic hemodialysis.

Complications related to subclavian catheters for hemodialysis. Report and review.

Personal experience with subclavian vein cannulations for hemodialysis are given, and the pertinent literature on the subject is reviewed. Two hundred subclavian dialysis catheters were placed in 148 patients who kept them in place for a total of 2,798 days. Immediate complications were two pneumothoraxes and two hemothoraxes due to subclavian artery puncture. Seventeen cases of bacteremia were related to subclavian catheter infections. In 1 case, a complication of sepsis was a vertebral osteomyelitis. Clinical evidences of subclavian vein thrombosis occurred in 5 cases. Life-threatening complications were met in 2 cases: 1 with pericardial tamponade due to right atrium perforation and 1 with mediastinal hematoma and right hemothorax due to superior vena cava perforation. Review of the literature indicates that pneumothoraxes and/or hemothoraxes occurred in 1.7% of the catheter insertions and that sepsis related to subclavian dialysis catheters occurred in 8.9% of the patients. As systematically investigated subclavian vein thrombosis involved at least 50% of the patients. Our 2 personal cases of life-threatening complications and 14 similar cases of the literature were analyzed: left subclavian catheters were associated with superior vena cava perforation with right hemothorax or mediastinal hematoma, while right subclavian catheters gave atrial perforation with pericardial tamponade. Death occurred in 3 of 16 cases, and emergency surgery was required in 5 of 16 cases. Taking into account all these complications, recommendations are made for the use of subclavian dialysis catheters.

Pellagra: unusual cause of paranoid delirium in dialysis.

A 60-year-old woman treated by maintenance haemodialysis refused to take part of the usual vitamin supplements for many years. After an intercurrent illness with profound malnutrition, she developed a paranoid delirium and some behavioural disorders; concomitant diarrhoea and a skin rash were noted. Parenteral nicotinamide (500 mg/day) resulted in a complete recovery from the mental disorders after five days. Other causes of mental disturbance as a result of dialysis could be ruled out. However an asymptomatic underlying hypothyroidism may have been one of the conditioning factors as well as the failure to administer nicotinamide supplements during an acute illness. Neurological pellagra could thus be considered as a rare but reversible cause of mental disorders in patients on maintenance haemodialysis.

Infections associated with subclavian dialysis catheters: the key role of nurse training.

Two hundred subclavian dialysis catheters were placed in 148 patients who kept them in place for a total of 2,798 days. Catheterization time ranged from 1 to 79 days with an average of 14.0 +/- 1.0 days per catheter and 18.9 +/- 1.0 days per patient. Twenty nine catheters were infected, 17 of which were the source of bacteremias due to Staphylococcus epidermidis in 13 cases and to Staphylococcus aureus in 4 cases. The incidence of sepsis was not significantly greater in diabetic patients, in patients with corticotherapy or in patients presenting an underlying systemic disease. On the contrary, the incidence was greater in hospitalized patients (15 bacteremias during 1,948 catheter days) than in ambulatory patients (2 bacteremias during 850 catheters-days) as well as during a period corresponding to a greater number of untrained nurses enrolled in the dialysis team. During this period, 6 sepsies occurred in 19 catheters (other periods: 7 sepsies/116 catheters, p less than 0.01). 6 of 28 nurses had less than 3 months of professional experience (other periods: 1 of 25, p less than 0.01). These data underline the key role of nurse training in the prevention of catheter-related infections.

Impaired phagocytic activity of neutrophils in patients receiving haemodialysis: the critical role of iron overload.

The metabolic burst (as measured by the spontaneous and stimulated nitroblue tetrazolium tests), the phagocytosis of heat inactivated bakers' yeast and of Staphylococcus aureus, the killing of Staph aureus, and the myeloperoxidase activity of polymorphonuclear neutrophils were studied in 11 patients receiving maintenance haemodialysis. Of these patients, six were polytransfused and had high serum ferritin concentrations (mean 5940 (SD 2925) micrograms/l; group 1), and five had normal serum ferritin values (mean 171 (116) micrograms/l; group 2). Patients in group 1 had a history of more infectious episodes (0.167 v 0.025 per patient per month) and significantly more genitourinary infections (p = 0.015) than those in group 2. Phagocytosis and myeloperoxidase activity were severely reduced in group 1 but normal in group 2. Percentages of neutrophils ingesting one or more particles together with the index of phagocytosis in patients' serum were inversely correlated with serum ferritin concentrations. Four patients in group 1 were treated with desferrioxamine, and after six to 18 weeks of treatment phagocytosis and myeloperoxidase activity had returned to normal in three of them. These data suggest that in patients receiving haemodialysis iron overload due to multiple transfusions plays an important part in the mechanisms underlying the susceptibility to bacterial infections, mediated at least partially through impaired neutrophil function.

Mechanisms of hypouricemia in the syndrome of inappropriate secretion of antidiuretic hormone.

Hypouricemia seen with hyponatremia related to the syndrome of inappropriate secretion of antidiuretic hormone (SIADH) results from an increase in uric acid renal clearance. We studied the mechanism of the increase of uric acid excretion in 6 SIADH patients through pyrazinamide (PZA), which decreases tubular secretion of uric acid, and sulfinpyrazone (SPZ) which decreases post-secretory reabsorption of uric acid. 3 g of PZA decreased the absolute uric acid excretion from 428 +/- 244 to 105 +/- 47 micrograms/min (mean +/- SD, p less than 0.01), and 300 mg of SPZ increased the uric acid to creatinine clearance ratio from 0.31 +/- 0.05 to 0.52 +/- 0.05 mg/dl glomerular filtration rate (mean +/- SEM, p less than 0.001), which represent an increment about half of that observed in the control group. The increase of uric acid clearance in SIADH seems to result from a decrease in the post-secretory reabsorption of uric acid. After SPZ, we saw a decrease of natriuresis from 5.6 +/- 1.4 to 1.8 +/- 0.3 mmol/h (p less than 0.001), without any change of urinary flow or urinary potassium excretion.

[Comparative effects of oral water load of different mineral compositions on the excretion of ions and oxalic acid]. / Effets comparés sur l'excrétion des ions et de l'acide oxalique de charges orales en eaux de compositions minérales différentes.

The effects on urinary excretion of a 1500 ml daily load of three drinking waters with different ionic contents were studied in six normal subjects. Diuresis was similarly increased by the three waters of an amount equal to the load. Urine output of urea, creatinin, uric acid, phosphate, potassium, magnesium was not significantly modified by the three waters as compared to a control period. Natriuresis was significantly increased following the intake of the water which contained sodium as well as calciuria with the water containing calcium. Urine output of oxalate was increased by the three waters in correlation with the free water content of the load. This effect is probably due to a reduction in passive tubular reabsorption of oxalate since a similar effect was observed with an equivalent water load given by intravenous route. Nevertheless, due to the dilution of urine, the index of urine saturation for calcium oxalate was diminished by the three waters.

Inappropriate secretion of antidiuretic hormone treated with frusemide.

Seven out of nine patients with chronic inappropriate secretion of antidiuretic hormone were successfully treated with 40 mg frusemide daily. One patient needed 80 mg, and the remaining patient achieved only a small increase in diuresis after 40 mg frusemide; this was probably related to his low creatinine clearance. In order to maintain a salt intake high enough to compensate for the loss of urine electrolytes 3 to 6 g sodium chloride was added as tablets to the sodium-free diet in six patients. Hypokalaemia occurred in five patients but was easily corrected with either supplements of potassium chloride or a potassium-sparing diuretic. These findings add further weight to evidence that Frusemide is a good alternative for the treatment of patients with inappropriate secretion of antidiuretic hormone who cannot tolerate water restriction.