Antihypertensive effect of beta blockade in renal transplant recipients with or without host kidneys

Host kidneys may contribute considerably to hypertension after renal transplantation. Their role in sustaining hypertension is more prominent if glomerulonephritis (GN) than if interstitial nephritis (IN) is the original renal disease. We compared the antihypertensive effect of beta-blockade in IN (n = 10) and GN (n = 19) hypertensive renal transplant recipients with host kidneys in situ with those who had undergone bilateral nephrectomy (BN, n = 10). Pretreatment blood pressures were comparable in BN, IN, and GN patients, being 165 +/- 6/108 +/- 3, 172 +/- 5/104 +/- 3, and 161 +/- 3/104 +/- 1, mmHg, respectively. Blood pressure did not change on beta-blockade in BN patients, whereas it decreased significantly more (P less than 0.001) in GN than in IN patients, changes of mean arterial pressure being -107 +/- 1.0, -14.9 +/- 1.3, and -6.8 +/- 1.6%, respectively. This failure to respond to beta-blockade in patients without host kidneys may be related to low activity of the renin-angiotensin system or to functional denervation of the grafted kidney. Further investigations of this phenomenon may clarify the mechanism of antihypertensive action of beta-blockade as well as the nature of hypertension after renal transplantation.     

A comparative study on the diagnostic value of prostatic acid phosphatase (PAP) and prostatic specific antigen (PSA) in patients with carcinoma of the prostate gland

Serum prostatic-specific antigen (PSA) and prostatic acid phosphatase (PAP) were determined simultaneously in 241 patients presented to the Urology Department. The patients consisted of 140 prostatic carcinoma patients (34 newly diagnosed and 106 previously treated) and 101 patients with benign prostatic hypertrophy (BPH). Prostatic acid phosphatase was measured by two different methods, an enzymatic method (PAP-EA, Boehringer) with tartrate inhibition and an immunoenzymetric assay (PAP-IEMA, Hybritech). The concentration of prostatic specific antigen in serum was measured using a recently introduced immunoradiometric assay (PSA-IRMA, Hybritech). Receiver operating characteristic curves were constructed to compare the diagnostic value of the different tests at different cutoff values. The diagnostic efficiencies of the PAP-EA and the PAP-IEMA appeared to be similar. A better diagnostic efficiency for PSA compared to PAP was found independent of the cutoff value. The upper-normal limit of 2.7 micrograms/l for PSA, as suggested by the manufacturer and mentioned in the literature introduces too many false-positive results. We therefore selected 10 micrograms/l as the upper-normal limit for PSA (sensitivity 57%, specificity 88%). Combined sensitivity found for PAP + PSA was 37% with a specificity of 97%. A literature survey is included to allow better comparison with data published elsewhere.     

Cardiovascular effects of caffeine and nifedipine

Because caffeine and nifedipine may have opposing effects on intracellular calcium concentration, a possible interaction between these agents on blood pressure and heart rate was examined. With a randomized, double-blind, crossover design, 10 normal, caffeine-abstaining subjects received caffeine, 300 mg, or placebo followed by nifedipine, 10 mg, or placebo. Caffeine increased blood pressure, whereas nifedipine reduced it and caused a reflex increase in heart rate. With caffeine pretreatment, nifedipine decreased blood pressure significantly more than with placebo pretreatment. However, nifedipine reduced blood pressure to the same absolute level on both the caffeine and placebo pretreatment days. The reflex increase in heart rate after nifedipine was not affected by prior caffeine or placebo administration. Caffeine pretreatment does not alter the cardiovascular responses to nifedipine but the pressor effect of caffeine is completely reversed by subsequent nifedipine administration.     

FEASIBILITY OF CONDUCTING CARDIOVASCULAR OUTCOME RESEARCH IN AUSTRALIAN GENERAL PRACTICE: RESULTS FROM THE ANBP2 PILOT STUDY

1. The present study aimed to determine the feasibility of conducting a 5 year cardiovascular outcome trial of the treatment of 6000 elderly hypertensive patients in Australian general practices. 2. General practitioners (GPs) were invited to participate by mail and personal follow-up. Patient records were reviewed to identify subjects for a blood pressure (BP) screening programme. Blood pressure was measured on three occasions and eligible subjects were included if the average BP was 160 mmHg systolic or 90 mmHg diastolic if systolic BP was 140 mmHg. 3. Seven hundred and forty-one GPs were approached and 89 were enrolled in the study (12% of mail invites and 75% of those receiving a personal contact). In 16 practices where screening was completed, 82 000 records were reviewed to identify 4% patients eligible for screening. Twenty-two per cent of eligible subjects attended screening. Of 1938 subjects screened, 180 (9%) had BP 5=160/90 mmHg. Forty-seven percent of subjects (n = 916) were receiving antihypertensive therapy and 184 (20%) were withdrawn from therapy. One hundred and sixteen (63%) of these subjects had BP return to study entry levels within 6 weeks. Fifty-seven newly diagnosed and 81 previously treated subjects were randomized (7% of the screened population). 4. Based on the high participation rate of GPs, the response rate of patients to attend a BP screening programme and the 7% randomization to screening ratio for entry into the study, the ANBP2 pilot study has demonstrated that it is feasible to recruit subjects from Australian general practices to a cardiovascular outcome trial.     

Adverse reactions attributed to sumatriptan

There are several reports on cardiac adverse reactions attributed to the antimigraine drug sumatriptan in the recent literature. In order to assess the frequency and the character of adverse reactions to sumatriptan, a postmarketing cohort study was performed one year after registration of the drug in The Netherlands. With assistance of 86% of the drug dispensing general practitioners in The Netherlands, 1727 patients who had received sumatriptan were traced in July, 1992. Via their general practitioners, a questionnaire about use of sumatriptan, adverse reactions and other medication was sent to the patients in December 1992. During the study period, seven patients were lost to follow-up. Of the 1720 remaining patients, 1202 (70%) responded to the questionnaire, of whom 1187 had actually used sumatriptan. The most frequently reported suspected adverse reactions were paraesthesiae (139 patients, 95% CI 9.9%–13.5%) and dizziness (96 patients, 95% CI 6.5%–9.7%). Chest pain after use of sumatriptan was reported by 94 patients (7.9%, 95% CI 6.4%–9.4%), and according to the close temporal relationship with the intake of sumatriptan and a positive rechallenge, a causal relationship was probable in most of those patients. The frequency of chest pain attributed to sumatriptan was higher in females (9.0% vs 4.6%; relative risk 1.9, 95% CI 1.1–3.4). Age and hypertension were not associated with chest pain attributed to sumatriptan. Dyspnoea attributed to sumatriptan was reported by 26 patients (2.2%), and was associated with obstructive lung disease (relative risk 5.4 95% CI 1.7–16.9). Thus, in view of the high frequency of chest pain after use of sumatriptan and reports in the literature of cardiac disturbances, including myocardial infarction, cautious use of the drug is advised.     

Increased collagen IV layer in the basal membrane area of the capillaries in severe chronic venous insufficiency

Lipodermatosclerosis is a sign of severe chronic venous insufficiency. In this stage of CVI one can find capillary leakage of water and plasmaproteins which results in a higher capillary filtration rate. In skin biopsies the result of this process can be seen as a pericapillary halo. The group of Burnand recently described fibrinogen deposits in this area. We studied the capillaries and their surrounding tissue to determine the thickness of the collagen IV deposits. In severe CVI with lipodermatosclerosis a significant increase of the collagen IV layer was observed. Collagen IV thickness was measured by an index method. The collagen IV thickness for this purpose refers to the capillary diameter. It can be suggested that the increase of the venous pressure in the capillaries leads to leakage of several proteins and namely fibrinogen. As a result of the increase of fibrinogen the collagen IV layer becomes thicker which leads to a decreasing function of the capillaries. In this way an auto-amplification mechanism maintains CVI. An other explanation can be induction of collagen IV due to the high capillary pressure in CVI.     

Dexfenfluramine in the treatment of severe obesity: a placebo-controlled investigation of the effects on weight loss, cardiovascular risk factors, food intake and eating behaviour.

Dexenfluramine, an effective and safe serotoninergic drug with anorectic and possible food-selection-tuning properties, was investigated in a placebo-controlled study of 1 year's duration in severe and refractory obesity. The aim of the study was to assess weight loss, and changes in cardiovascular risk factors, food intake and eating behaviour. Dexfenfluramine- and placebo-treated patients achieved a similar weight loss (greater than 10% of initial weight, by 39.5 and 30.0%, greater than 20% of initial overweight by 42.1% and 32.5% and greater than 10 kg by 41.4 and 33.3%, respectively, of the initial cohorts). Furthermore, the decreases in weight (10.7 vs. 8.0 kg), in body mass index (3.9 vs. 2.9 kg m2) and in waist/hip ratio (0.04 vs. 0.02) were not significantly different. After discontinuation of the drug, the increase in weight (2.8 vs. 1.0 kg) was significantly higher in the dexfenfluramine-treated group. Except for a borderline better effect on glucose of dexfenfluramine, both groups showed similar beneficial changes in food intake and cardiovascular risk factors. Eating behaviour in response to emotional and external stimuli was comparable in the two groups, but placebo-treated patients had to restrain their eating more in order to achieve the same weight loss. Notwithstanding the fact that weight losses and an associated amelioration of health-risk factors were of similar magnitude in dexfenfluramine- and placebo-treated patients, dexfenfluramine might have a useful role in promoting a less stressed adherence to prolonged restriction of energy intake in the severe and refractory obese subject.     

Forced oscillation technique. Reference values for total respiratory resistance obtained with the Siemens Siregnost FD5.

Total respiratory resistance (Rrs) was measured by the application of a sine wave of airflow to the mouth at an oscillation frequency of 10 Hz. The instrument used was the Siemens Siregnost FD5. The Rrs data were correlated with height, age, sex, and weight in 73 patients and 29 healthy subjects. The patients took part in a rehabilitation program for restoration of their locomotion function. Both groups had normal lung function (VC, FEV1) and no signs of pulmonary disease. The only important determining factor for the value of the Rrs was height. The mean Rrs of 102 subjects was 0.29 +/- 0.08 kPa.1-1.s. Other studies gave values between 0.23 +/- 0.05 and 0.32 +/- 0.10 kPa.1-1.s.     

Prospective study on the value of endosonographic follow-up after surgery for esophageal carcinoma

Background: Half of the patients who undergo surgery for cancer of the esophagus or gastric cardia present with recurrent disease within 2 years after the operation. We investigated the value of endosonography for the early detection of recurrent disease. Methods: Forty-three patients entered a follow-up protocol in which endosonography was performed every 6 months within the first 2 years after resection. Results: During 16 of a total of 66 examinations, suspicious abnormalities were found. In three patients free fluid was seen, but recurrence could not be confirmed during follow-up. In eight patients suspicious lymph nodes were seen; six died within 6 months, one was alive with a proven recurrence at 6 months, and one was alive without recurrence at 22 months. In five patients focal wall-thickening or a mass was seen; three died within 6 months, and two were alive with a proven recurrence at 2 and 5 months. After exclusion of free fluid, the positive predictive value of abnormalities on endoscopic ultrasonography (EUS) was 92%. Conclusions: Endosonography, performed at 6-month intervals after resection of cancer of the esophagus or gastric cardia, is accurate in the early detection of locoregional recurrent disease. Two thirds of the patients were still without symptoms when the recurrence was found. (Gastrointest Endosc 1997;46:487-91.)