Arm position and blood pressure: a risk factor for hypertension?

The objective of this study was to re-evaluate the effect of arm position on blood pressure (BP) measurement with auscultatory and oscillometric methods including ambulatory blood pressure monitoring (ABPM). The setting was the hospital outpatient department and the subjects chosen were normotensive and hypertensive. The effect of lowering the arm from heart level on indirect systolic BP (SBP) and diastolic BP (DBP) measurement as well as the importance of supporting the horizontal arm were measured. In the sitting position, lowering the supported horizontal arm to the dependent position increased BP measured by a mercury device from 103+/-10/60+/-7 to 111+/-14/67+/-10 mmHg in normotensive subjects, a mean increase of 8/7 mmHg (P<0.01). In hypertensive subjects, a similar manoeuvre increased BP from 143+/-21/78+/-17 to 166+/-29/88+/-20 mmHg, an increase of 23/10 mmHg (P<0.01). Combined results from normotensive and hypertensive subjects demonstrate a direct and proportional association between BP (SBP and DBP) and the increase produced by arm dependency. Similar changes and associations were noted with oscillometric devices in the clinic situation. However, supporting the horizontal arm did not alter BP. Of particular interest, analysis of 13 hypertensive subjects who underwent ABPM on two occasions, once with the arm in the 'usual' position and once with the arm held horizontally for BP measurement during waking hours, demonstrated changes comparable to the other devices. The mean 12-hour BP was 154+/-19/82+/-10 mmHg during the former period and significantly decreased to 141+/-18/74+/-9 mmHg during the latter period (P<0.01). Regression analysis of the change in SBP and DBP with arm position change again demonstrated a close correlation (r(2)=0.8113 and 0.7273; P<0.001) with the artefact being larger with higher systolic and diastolic pressures. In conclusion, arm movements lead to significant artefacts in BP measurement, which are greater, the higher the systolic or diastolic pressure. These systematic errors occur when using both auscultatory and oscillometric (clinic and ABPM) devices and might lead to an erroneous diagnosis of hypertension and unnecessary medication, particularly in individuals with high normal BP levels. Since clinical interpretations of heart level vary, the horizontal arm position should be the unambiguous standard for all sitting and standing BP auscultatory and oscillometric measurements.

Consumption of non-steroidal anti-inflammatory drugs and the development of functional renal impairment in elderly subjects. Results of a case-control study.

AIMS: The aim of the present study was to explore the level of risk associated with community use of non-steroidal anti-inflammatory drugs (NSAIDs). METHODS: We carried out a matched case-control study of the relationship between recent use of NSAIDs and the presence of functional renal impairment present at the time of hospitalisation with a range of clinical problems. Cases (n = 110) were consecutive patients admitted acutely to hospital who had serum creatinine levels greater than or equal to 0.15 mmol l(-1) , which improved by 20% or more within the next 14 days, or prior to discharge from hospital. Controls (n= 189) were subjects of the same sex and age (to within 5 years) as the cases, who were admitted to the same hospital, who had normal serum creatinine levels (<0.12 mmol l(-1) throughout their hospital stay. Information on a number of study factors, including recent use of aspirin and other NSAIDs, was obtained by structured interview. RESULTS: Overall, there was a weak association between consumption of NSAIDs (including non-prophylactic aspirin) and the development of functional renal impairment-adjusted odds ratios (OR) with use of NSAIDs in the previous week or in the previous month: OR 1.5 (95% CI 0.80, 2.9) and 1.8 (95% CI 0.97, 3.4) respectively. In subjects with a previous history of renal disease the adjusted OR was 6.6 (0.75, 57.8) and in those with a history of gout or hyperuricaemia the OR was 7.2 (1.3, 40.2). There was a weak positive relationship between the dose of drug consumed in the previous week and the odds of functional renal impairment. The relationship between risk and published figures for drug half-lives (t1/2) was stronger. The odds ratio increased from 1.2 (95% CI 0.61, 2.4) with a t1/2 < or = 4 h, to 4.8 (1.5, 15.8) with a t1/2 of < or = 12 h (P=0.012, test for trend). This relationship remained statistically significant after adjustment for a number of clinical variables and the dose of drug ingested. CONCLUSIONS: NSAIDs are an important cause of functional renal impairment in subjects with renal disease or a history of gout or hyperuricemia. The half-life of the drug is more important than the ingested dose in determining the risk of this outcome. Long half-life drugs should be avoided in individuals who are at risk of developing renal impairment.

The renal medulla in acute renal allograft rejection: comparison with renal cortex.

A retrospective cohort study was undertaken to evaluate the diagnostic value of the renal medulla in acute renal allograft rejection (ARAR). One hundred and ninety-five biopsies from 98 patients were randomly selected out of 565 transplant biopsies. Biopsies were graded blindly from Grade 0 (no rejection) to Grade 3 (severe rejection) using standard criteria; ARAR was confirmed by a fall in all cases of mean serum creatinine concentration from 0.331 +/- 0.182 to 0.184 +/- 0.079 mmol/l, with anti-rejection therapy. In the 43 biopsies which contained both cortex and medulla, the ARAR grades and the intensities of mononuclear cell, plasma cell, polymorphonuclear cell and eosinophil infiltrates, and of interstitial oedema and haemorrhage, were similar in cortex and medulla (Spearman's Rank Correlation r = 0.55-0.81, P < 0.001). The sensitivity, specificity and overall accuracy of medullary changes in predicting ARAR changes in the cortex were 77%, 100% and 38%, respectively. Acute vascular rejection changes could not be compared between renal cortex and renal medulla because of the anatomical differences between cortex and medulla. Further evaluation of ARAR in the all 195 biopsies, of which 188 had cortical tissue and 50 had medullary tissue, showed no significant differences in histological features (P > 0.05), except for more cortical biopsies with plasma cells (29%) than medullary biopsies with plasma cells (10%; P < 0.02). It is concluded that: (1) ARAR histological changes are similar in cortex and medulla; (2) the predictive value of ARAR medullary changes for cortical rejection changes has low sensitivity (77%) and high specificity (100%).(ABSTRACT TRUNCATED AT 250 WORDS)

The hypo-echoic cortical rim in lupus nephritis.

Hypo-echoic cortical rims are an unusual ultrasound finding in patients with renal disease. A case report is presented of a patient with lupus nephritis who demonstrated hypo-echoic cortical rims. A brief review of the pathological causes of hypo-echoic cortical rims is given.

Eosinophils in acute renal allograft rejection.

Tissue eosinophils have been previously implicated in allograft rejection and graft loss. The aim of this study was to evaluate the role of eosinophils in acute renal allograft rejection. Data from 71 patients with 114 renal biopsies with acute allograft rejection were compared with those from 26 controls. The median tissue eosinophil density (0.4-1.1 eosinophils per micron2 x 10(6)) and the median peripheral blood eosinophilia (1.5-3.0%) in all grades of acute interstitial rejection and in acute vascular rejection were higher than in controls (0.0 eosinophils per micron2 x 10(6), p < 0.0023, and 0.9%, p < 0.035). In all grades of rejection, 36-54% of biopsies had tissue eosinophil density > or = 1 eosinophil per micron2 x 10(6), and 20-36% of patients had peripheral blood eosinophilia > or = 4%, compared with 0% and 4%, respectively, in controls (p < 0.000 and p = 0.0245). The sensitivity, specificity and overall accuracy of predicting acute rejection with tissue eosinophil density > or = 1 eosinophil per micron2 x 10(6) is 41%, 100% and 52%, and for peripheral blood eosinophila > or = 4% is 23%, 96% and 40%, respectively. The median tissue eosinophil density in acute rejection with graft loss was 1.9 eosinophils per micron2 x 10(6) compared to 0.2 eosinophils per micron2 x 10(6) in acute rejection without graft loss (p = 0.014), and 67% of acute rejection with graft loss had tissue eosinophil density > or = 1 eosinophil per micron2 x 10(6) compared with 28% of acute rejection without graft loss (p = 0.028).(ABSTRACT TRUNCATED AT 250 WORDS)

Analgesic nephropathy in the 1990s--an Australian perspective.

Analgesic nephropathy or analgesic abuse-associated analgesic nephropathy (AA-AAN) is a disease of the twentieth century. The emergence of AA-AAN was due to aggressive marketing of analgesics and the susceptibility of individuals with addictive personalities to analgesic abuse. Analgesic abuse resulted in major morbidity and mortality from renal disease and renal failure, premature atherogenesis with cardiovascular diseases, and the other aspects of the analgesic syndrome; these conditions have had heavy demands upon health budgets. Legislative restriction of analgesic sales in Australia has resulted in a decline in analgesic abuse and end-stage renal failure from AA-AAN. There have also been changes in the analgesic syndrome. However, the long-term risks of transitional cell carcinoma of the uroepithelium remain as a legacy of analgesic abuse and AA-AAN. Nonsteroidal anti-inflammatory drug-associated analgesic nephropathy (NSAID-AAN) has emerged as a distinct clinical syndrome, and may become a significant health problem in view of the widespread use and misuse of NSAIDs.

Pattern of renal dysfunction in analgesic nephropathy--comparison with glomerulonephritis.

Comprehensive renal function tests were performed in 84 patients with analgesic nephropathy, 33 glomerulonephritis patients matched for creatinine clearance, and 30 control subjects. A system of 1-day renal function tests including urine microscopy, creatinine clearance, phenolsulphonphthalein excretion, urine concentration and acidification, and electrolyte excretion, was used. Patients with analgesic nephropathy were found to have significant sterile pyuria and haematuria, even those with mild renal insufficiency, significantly reduced concentrating ability and a distal acidifying defect, and a tendency to impaired sodium conservation. These function defects are consistent with the primary lesion of renal papillary necrosis in analgesic nephropathy; the detection of these defects have implications in patient management.

Reversal of acute glomerular renal allograft rejection: a possible effect of OKT3.

A major cause of renal allograft loss is glomerulovascular rejection. This case report is about an episode of histologically proven acute glomerular rejection that was successfully reversed. Monoclonal antibody OKT3 may have been the effective agent.

Use of the fistula assessment monitor to detect stenoses in access fistulae.

Twenty-three unselected hemodialysis patients with functioning access arteriovenous fistulae were studied prospectively to determine the best technique for detecting stenoses within the fistulae. Combined clinical assessment and fistula assessment monitoring were compared with transbrachial angiography. Fistula assessment monitoring was more accurate (96%) than combined clinical assessment (accuracy, 52%) in stenosis detection. Complications of angiography occurred in 17% of patients; there were no complications of fistula assessment monitoring. Fistula assessment monitoring was better than combined clinical assessment in predicting clinical outcome for arteriovenous fistulae over 6 months and was as good as angiography. Routine fistula assessment monitoring could reduce inappropriate angiography and detect clinically significant silent stenoses. It is an ideal method for monitoring arteriovenous access fistulae.

Acute renal failure due to acute pyelonephritis.

We report a case of biopsy-proved acute pyelonephritis which caused acute renal failure. Despite appropriate antibiotic therapy, recovery of renal function was slow and incomplete. Renal papillary necrosis was an apparent complication, which the patient may have been predisposed to by alcoholism. Although rare, acute pyelonephritis is an important consideration in the differential diagnosis of acute renal failure because of the need for specific therapy.

Urinary corticotropin-releasing hormone immunoreactivity is elevated during human pregnancy.

Plasma corticotropin-releasing hormone immunoreactivity (CRH IR) rises with gestational age in women. In order to investigate the physiological changes of the hormone in pregnant women's urine, CRH IR was measured by radioimmunoassay in urine collected over a 24-hour period, a blood sample and a subsequent single collection of urine after the 24-hour collection (spot urine). Plasma CRH IR in pregnant subjects, 8682.8 +/- 2063.0 pg CRH IR/ml plasma (mean +/- SEM, n = 25), was significantly higher than that in the non-pregnant controls (7.2 +/- 1.6 pg/ml, n = 5; separate t = 4.21, p = 0.0003, d.f. = 24). Similarly, pregnant women had higher spot urine CRH IR - 54.6 +/- 15.5 pg/mumol creatinine (Cr) versus 5.0 +/- 0.5 pg/mumol Cr (separate t = 3.20, p = 0.0038, d.f. = 24.0) - and 24-hour urine CRH IR - 13.7 +/- 1.2 pg/mumol Cr compared with 7.7 +/- 0.8 pg/mumol Cr (separate t = 4.28, p = 0.003, d.f. = 24.4) than the non-pregnant cohort. The difference between urinary excretion of CRH IR as estimated by 24-hour urine (13.7 +/- 1.2 pg/mumol Cr) and spot urine (54.6 +/- 15.5 pg/mumol Cr) indicated that CRH IR in 24-hour urine may be degraded during storage. The weak associations between plasma and 24-hour urine CRH IR of pregnant women (correlation coefficient r = 0.34, p greater than 0.1), and total 24-hour urine and spot urine CRH IR (r = 0.25, p less than 0.1) further indicate CRH degradation. Plasma and spot urinary CRH IR, however, were strongly correlated (r = 0.80, p = 0.001). The total CRH IR excreted as estimated from the spot urine value (0.5 +/- 0.1 micrograms/day) compared with the total filtered load of CRH IR in the pregnant group (1306.9 +/- 324.6 micrograms/day) showed that 99.97% of the filtered CRH IR was reabsorbed or metabolized by the kidneys. Acidic gel chromatography of spot and 24-hour urine samples showed a CRH IR peak at CRH41 standard elution position (Kd = 0.5), indicating that the molecular form in urine is similar to the 41-residue standard. Pregnancy-induced hypertension correlated positively with plasma CRH IR (r = 0.62, p less than 0.001) and spot urine CRH IR (r = 0.46, p less than 0.01), and negatively with parity (r = -0.60, p less than 0.001). Plasma CRH IR and parity also negatively correlated (r = -0.41, p less than 0.05).(ABSTRACT TRUNCATED AT 400 WORDS)

Xanthogranulomatous pyelonephritis in a renal allograft: a case report.

We report a case of xanthogranulomatous pyelonephritis in a renal allograft. The kidney was not removed and there was an initial response to antibiotic therapy, with amelioration of toxicity and improvement in renal function. However, the kidney failed 10 months later in association with histological changes of chronic rejection.

Gangrenous colitis in the haemolytic-uraemic syndrome.

The cases of two children with the haemolytic-uraemic syndrome (HUS) in whom clinical signs of intussusception necessitated emergency surgical intervention are reported. Both patients had bilateral renal cortical necrosis and haemorrhagic gangrenous colitis; both subsequently died. The early recognition and appropriate management of HUS is advocated.