Is blood pressure variability related to activity of the sympathetic system?

1. In 70 patients with untreated essential hypertension, blood pressure variability was correlated to plasma catecholamines and to the response of blood pressure and peripheral flow to cold pressure and handgrip tests. 2. Supine blood pressure was recorded every 5 min, during 3 h. Variability was defined as the standard deviation of the mean of the readings in that period. 3. Blood pressure variability is positively and significantly correlated to the level of pressure and to age. 4. No significant correlation could be found with plasma catecholamines and sympathetic function tests. 5. It is concluded that blood pressure variability is related to the level of pressure but not to activity of the sympathetic nerves.

Shunt nephritis.

A case of nephritis occurring in a 40-year old patient with a ventriculojugular shung infected with staphylococcus albus is described. Circulating antistaphylococcal antibodies could be demonstrated. Renal manifestations disappeared after treatment with systemic antibiotics and surgical removal of the shunt.

Destructive sterile vesicoureteral reflux observed over a 12-year period.

The evolution over a 12-year follow-up period from only slightly damaged kidneys to end-stage renal disease due to sterile ureteral reflux is reported.

Serum binding of quinidine in experimental acute renal failure.

Quinidine serum binding is increased in some patients with acute renal failure, but in animals with renal failure conflicting results were published. Therefore, serum binding of quinidine, papaverine and phenylbutazone was studied by equilibrium dialysis in rabbits and rats with acute renal failure induced either by injection of uranyl nitrate or ligation of the ureters. From the results it appears that, in animals, quinidine binding changes are different according to the model used for induction of the renal failure, regardless of the species studied. After ligation of the ureters, lipoprotein concentration increases, but the meaning of this increase for increased serum quinidine binding is not clear.

The mechanism of action of Bay g 2821: a new diuretic.

Acute water diuresis and hydropenic studies were carried out in 7 healthy volunteers to investigate the site of action of a new non-sulphonamide diuretic, Bay g 2821. The effects of the drug on the concentrating and diluting mechanism, and on the renal handling of sodium, potassium, calcium, phosphorus and uric acid were studied. The results suggest sites of actions of Bay g 2821 at the proximal tubule and the medullary portion of the ascending limb of the loop of Henle.

Influence of acute renal failure on the protein binding of drugs in animals and in man.

Serum protein binding of phenylbutazone has been measured in the rat, guinea pig, cat, rabbit and dog, and the influence on it of renal failure induced by uranyl nitrate injection has been studied. In all speciies a clearcut decrease in binding was observed after the occurrence of renal failure; the time course of the fall in binding correlated well with development of renal failure. In further experiments, serum protein binding of two acidic drugs (phenylbutazone, warfarin), two basic drugs (papaverine, quinidine) and one neutral drug (digitoxin) was studied in rabbits with experimental renal failure, and the results compared with those obtained in patients with acute renal failure. In the rabbits, a decrease in the binding of phenylbutazone, warfarin, papaverine and quinidine was found, whereas protein binding of digitoxin was unchanged. In man, there was a definite fall in protein binding of phenylbutazone and digitoxin, a small decrease for warfarin and papaverine, and a slight increase for quinidine.

Familial partial target organ resistance to thyroid hormones.

A 30-year old woman with a history of recurrent goiter, who had undergone two partial thyroidectomies, is described. She presented with tachycardia, nervousness and a fine tremor of the fingers. Initially, she had normal serum thyroid hormone levels: thyroxine (T4 (D)) 11.6 MUG/100 ML, TRIIODOTHYRONINE (T3) 138 ng/100ml, normal levels of binding proteins and a very high serum thyrotropin (TSH), 98 muU/ml. During follow-up T4 (D) increased to 17.2 mug/100 ml, T3 increased to 277 ng/100 ml, while TSH decreased to 11 muU/ml. There was an exaggerated response of TSH to a peak value of 550 muU/ml after intravenous administration of 200 mug thyrotropin-releasing hormone (TRH). Administration of 60 mg prednisolone daily resulted in a blunting of the response to TRH. Administration of 50 mug T3 daily for 1 month resulted in a fall in serum TSH from 98 to 50 muU/ml. Later, when the serum TSH level had fallen spontaneously to 20 muU/ml, administration of 100 mug T3 daily for two weeks resulted in a fall in serum TSH to 5.3 muU/ml. Treatment with 20 mg carbimazole daily for 3 weeks resulted in a decrease in serum T4 levels with a concomitant increase of serum TSH. There was no evidence of pituitary enlargement and other pituitary hormone levels were normal. All the relatives studied (father, sister, three children) had elevated T4 levels with normal basal TSH values. It is concluded from this study that our patient presents evidence of partial resistance to thyroid hormones.

High intravenous doses of methylprednisolone for acute cadaveric renal allograft rejection.

In a group of 48 patients with a renal cadaveric allograft 38 acute rejection episodes were treated by increasing the daily prednisolone doses to 300 mg the first day, 200 mg the second day and 100 mg the third day, gradually tapering down over a matter of weeks. In a second group of 48 patients 39 acute rejections were treated by 1 g of methylprednisolone intravenously on alternate days with a maximum of four injections. Rejection treatment was successful in 26 of 38 in the first group (68%) and in 30 of 38 in the second group (76%). Complications such as gastrointestinal bleeding, aseptic necrosis and diabetes were more frequent in the first series.

Salmonella typhimurium infections in renal transplant patients. Report of five cases.

Five patients with Salmonella typhimurium infection after a renal cadaveric graft are described. Salmonella were isolated from the urine of four patients, from the stool of one patient, from the blood of two patients, from the hip joint of one patient and from the cerebrospinal fluid of one patient. Infections were difficult to eradicate and necessitated prolonged antibiotic treatment. Renal function only deteriorated after the infection in some patients; salmonellosis could have triggered the rejection of the graft. Impaired cell-mediated immunity due to immunosuppressive drugs may be considered to be a predisposing factor for this kind of infection. Higher humoral antibody titers against Salmonella were found in the patients most clinically ill.

Oral diazoxide contraindicated in severe hypertension with renal failure.

Diazoxide was given orally to nine hypertensive patients with renal failure and its effect on blood pressure and on glucose metabolism was studied. There was no long-term antihypertensive effect. During treatment insulin release and glucose assimilation after an intravenous glucose load were frankly impaired, but this impairment was reversible after stopping the treatment. Two major complications (diabetic ketoacidosis and pancreatitis) were observed. In view of these observations, the authors are of the opinion that oral diazoxide is contraindicated in the treatment of hypertension in patients with renal failure.