Body mass index and mortality in 'healthier' as compared with 'sicker' haemodialysis patients: results from the Dialysis Outcomes and Practice Patterns Study (DOPPS).

BACKGROUND: Haemodialysis (HD) patients with lower body mass index (BMI) have a higher relative mortality risk (RR), irrespective of race. However, only Asian Americans treated with HD have been found to have an elevated RR with higher BMI. Asian Americans on HD are 'healthier' than other race groups (i.e. have better overall survival). We hypothesized that an increased mortality risk might be associated with high BMI in a variety of other 'healthier' subgroups of HD patients. METHODS: The prospective Dialysis Outcomes and Practice Patterns Study (DOPPS) provided baseline demographic, comorbidity and BMI data on 9714 HD patients in the US and Europe (France, Germany, Italy, Spain, and the UK) from 1996-2000. Using multivariate survival analyses, we evaluated BMI-mortality relationships in HD subpopulations defined by continent, race (black and white), gender, tertiles of severity of illness (based on a score derived from comorbid conditions and serum albumin concentration), age (<45, 45-64, >or=65), smoking, and diabetic status. RESULTS: Relative mortality risk decreased with increasing BMI. This was statistically significant (P<0.007) except for the smallest subgroup of patients who were <45 years old and were also in the healthiest tertile of comorbidity. All else equal, BMI <20 was consistently associated with the highest relative mortality risk. Overall a lower relative mortality risk (RR) as compared with BMI 23-24.9, was found for overweight (BMI 25-29.9; RR 0.84, P=0.008), for mild obesity (BMI 30-34.9; RR 0.73, P=0.0003), and for moderate obesity (BMI 35-39.9; RR 0.76, P=0.02). CONCLUSION: In a wide variety of HD patient subgroups, differing with respect to their baseline health status, increasing body size correlates with a decreased mortality risk. This contrasts with the association between BMI and mortality in the general population, and deserves further study.

[Bilateral emphysematous pyelonephritis, a rare cause of acute renal failure]. / Beidseitige emphysematöse Pyelonephritis, ein seltener Grund für ein akutes Nierenversagen.

BACKGROUND: The emphysematous pyelonephritis is a life-threatening complication of a bacterial interstitial nephritis, and it occurs mainly in diabetics. The infection with optional anaerobic microorganisms, which are able to produce gas, is supported by a reduced state of resistance, a high glucose level in the tissue in diabetic derailment and ischemia in the infected organ, for example by a kidney infarction or by an obstructive uropathy. Mostly the inflammation occurs unilateral, only in 10% of all cases both kidneys are affected. Computer tomography allows a fast diagnosis by demonstrating gas accumulation in the kidney. Surgical measures and antibiotic therapy are the principal therapeutic methods. CASE REPORT: The example of a 55-year-old diabetic man with bilateral emphysematous pyelonephritis demonstrates the diagnostic and therapeutic possibilities. After a fast diagnostic procedure, immediate hemodialysis in uremia and bilateral nephrectomy let the patient survive in a stable clinical condition dependent on regular dialysis treatment.

[Angioplasty in the stenosed hemodialysis shunt: experiences with 100 patients and 166 interventions]. / Angioplastie am stenosierten Hämodialyseshunt: Erfahrungen an 100 Patienten mit 166 Eingriffen.

PURPOSE: Failing dialysis fistulas are a severe complication for patients treated by chronic haemodialysis. This study was undertaken to evaluate the technical aspects of percutaneous transluminal angioplasty (PTA) of shunts and to report on our experience in 100 patients. PATIENTS AND METHODS: In a 4-year period a total of 166 PTA procedures was performed in 100 haemodialysis patients with stenosis and occlusion of Brescia Cimino shunts and PTFE grafts (polytetrafluoroethylene). Patency rates were retrospectively evaluated for type and location of lesions, patient age, sex and the success of PTA. RESULTS: Technical success was achieved in 97% (n = 161). Complications appeared in 11 cases (6.6%). Shunt occlusion or rupture of a vein is rare. The cumulative patency rate for primary PTA treatment was 55% at 6 months, 47% at 12 months and 32% at 24 months and for repeat PTA treatment 87% at 6 months, 80% at 12 months and 70% at 24 months. Residual stenosis and diabetes mellitus significantly reduced the patency rate. CONCLUSION: PTA is an ideal method for accomplishing recurrent fistula failure due to its cost effectiveness and minimally invasive procedure. Recurrent stenosis has been a major problem of PTA as also in equal measure with surgical intervention.

Kidney-derived urinary antigens assayed with monoclonal antibodies for the detection of renal damage.

For the quantitation of kidney-derived Urinary Antigens (UA) monoclonal antibodies specific for antigens localized in cells of defined subunits of the nephron were applied in sandwich ELISA. Antigen excretion was measured in the urine of healthy individuals, patients suffering from various diseases, kidney transplant recipients, and healthy volunteers receiving therapeutic doses of antibiotic drugs. In healthy individuals, in patients with diseases primarily affecting the glomerulus, and in inactive phases of chronic diseases antigen excretion was low. Toxic drug effects enhanced antigenuria. Excretion of some or all of the antigens always indicated tubular alterations. The tests thus provide information on location and extent of acute primary tubular damage.

A controlled study of supplementation with essential amino acids and alpha-keto acids in the conservative management of patients with chronic renal failure.

Oral therapy with essential amino acids (EAA) or alpha-keto acids (alpha-KA) has been recommended in patients with renal failure, but quality and quantity of optimal protein intake are still controversial. This study compares sequentially the effect of supplementation with EAA, and with alpha-KA versus placebo in 15 ambulatory patients with chronic renal failure (average creatinine clearance 10.8 ml/min), maintained on a protein diet of 0.57 g/kg body weight (40 g for a 70-kg patient). The actual dietary intake averaged 0.55 g protein/kg and 27 kcal/kg according to repeated 7-day dietary recordings. After a 6-week baseline period on this diet, all patients received additionally 0.112 g EAA/kg for 6 weeks followed by a double-blind crossover study of 0.105 g alpha-KA/kg versus placebo supplementation for 6 weeks each. Fasting blood samples for multiple parameters, including 15 indicators for protein deficiency, as well as anthropometric and clinical data were evaluated every 3 weeks. Laboratory data revealed no indications of protein deficiency. Therapy with alpha-KA diminished serum phosphate concentration (p less than 0.05), however no other significant beneficial effects could be demonstrated during supplementation with either EAA or alpha-KA. Therefore, such supplementation to a 0.55-g/kg-protein diet appears superfluous in stable ambulatory patients with renal insufficiency.

Refractory period, sensory conduction velocity and visual evoked potentials before and after haemodialysis.

In 18 patients suffering from chronic renal failure (being haemodialysed three times weekly for 22.2 +/- 27.9 months), sensory conduction velocity and relative refractory period of the sural nerve were estimated immediately before and after dialysis. Before haemodialysis all but one patient had conduction velocities within the normal range (x +/- 2 SD), but 50% had prolonged refractory periods. After dialysis the refractory period decreased to become normal in all but one patient. Visual evoked potential latencies showed no systematic alterations. A membrane abnormality due to uraemic poisoning is assumed to cause the reversible prolongation of the refractory period.

Double-blind cross-over study with oral alpha-ketoacids in patients with chronic renal failure.

In 15 ambulatory patients with renal insufficiency (creatinine clearance, 9.9 +/- 3.0 ml/min) the effect of oral supplementation with alpha-ketoacids has been compared with that of placebo. The protein intake amounted to 0.55 g protein per kilogram body weight of high biological value, as estimated by dietary recordings. After a control period of 3 months the patients received, in a double-blind study, 1.05 g alpha-ketoacids/10 kg body weight per day or a placebo for 6 weeks with a subsequent cross-over. Fasting blood samples were analyzed at 3-week intervals for routine laboratory parameters and 17 proteins. Anthropometric and clinical data have been recorded every 3 weeks. While therapy with alpha-ketoacids diminished PO4 levels (P less than 0.05), no other significant effect could be demonstrated. No signs of protein deficiency existed either before or during alpha-ketoacid therapy. Therefore, supplementation with alpha-ketoacids appears to be superfluous in patients with renal insufficiency maintained on a 40-g protein diet.

Treatment with essential amino acids in patients on chronic hemodialysis: a double blind cross-over study.

Patients on chronic hemodialysis may suffer from a latent protein deficiency, and therapy with essential amino acids has been recommended. In a double blind cross-over study, 13 hemodialysis patients received orally 15.7 g of essential amino acids daily over a 3-month period. Patients were on a liberal diet, containing 1 g of protein per kilogram of body weight per day. Hemodialysis was adequate. Therapy resulted in an increase in urea, uric acid, C3 c complement factor and a fall in C4. Lysine levels increased and phenylalanine fell. Malnutrition could not account for the observed metabolic changes, which are more likely due to uremic metabolic disturbances. A liberal diet of 1 g of protein per kilogram of body weight appears sufficient for patients on hemodialysis. Treatment with essential amino acids offers no advantage.

[Dangers of a wrong diet in patients with renal insufficiency in the predialytic state or during chronic hemodialysis]. / Gefahren der Fehlernährung bei Patienten mit Niereninsuffzienz im prädialytischen Stadium und unter chronischer Hämodialyse

Patients with chronic renal failure and on chronic intermittent hemodialysis have several metabolic risks such as retention of urea and other products of nitrogen metabolism, catabolism, acidosis, edema, dehydration, hyper- and hypotension, hyperkalemia, renal osteopathy, and renal anemia. Uremic coma is usually avoided by balanced nutritional therapy and treatment with hemodialysis. A dietary regimen containing protein with high amounts of essential amino acids is an important part of treatment. In patients on chronic hemodialysis disorders of protein and amino acid metabolism are caused by either deficiency of essential ingredients of the food or by the metabolic defects due to chronic uremia.

[The clinical value of sequential renal scans with 131 iodo-hipuran and renal perfusion with 99mtc compounds using computer analysis (author's transl)]. / Klinischer Wert der Nierensequenzszintigraphie mit 131Jod-Hippuran und der Nierenperfusion mit 99mTc-Präparaten nach Computerverarbeitung

Two methods of sequential scintigraphy are considered critically: a) Quantitative computer evaluation of nephrograms obtained by a gamma camera using 131Iodo-Hipuran. b) Quantitative flow studies of the kidneys after bolus injections of 99mTc preparations. Statistical evaluation of data from 171 patients examined by both methods has shown that the isotope nephrogram is not sufficiently sensitive for diagnostic purposes. Isotope nephrography combined with estimations of effective renal plasma flow on each side separately is of value to the urological surgeon by providing important information regarding severe degrees of renal functional impairment. Perfusion measurements, using a gamma camera and 99mTc preparations, are a promising survey method for the diagnosis of renal artery stenosis. (Much of this work is contained in a dissertation by C. Knick).