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L Arisz

Publications and source records attributed to L Arisz.

At least 19 recordsLinked to original sources
PubMed1999

A rise in plasma creatinine that is not a sign of renal failure: which drugs can be responsible?

This is a review of the available information about drugs which cause an increase in plasma creatinine concentration without decreasing glomerular filtration rate (GFR). The GFR is the main, but not the single, determinant of the plasma creatinine levels. Several drugs, such as cimetidine, trimethoprim, corticosteroids, pyrimethamine, phenacemide, salicylates and active vitamin D metabolites, have been reported to increase plasma creatinine without influencing its glomerular filtration. Cimetidine, trimethoprim, pyrimethamine and salicylates can inhibit secretion of creatinine by the proximal tubule. Corticosteroids and vitamin D metabolites probably modify the production rate and the release of creatinine. The exact mechanism of phenacemide-creatinine interaction is not fully explained. These drug-induced alterations in plasma creatinine concentration have clinical significance when GFR is estimated by using plasma creatinine.

Adrenal Cortex Hormones↗
PubMed1999

Glomerular filtration rate estimation from plasma creatinine after inhibition of tubular secretion: relevance of the creatinine assay.

BACKGROUND: Estimation of glomerular filtration rate (GFR) from plasma creatinine concentration after inhibition of tubular creatinine secretion with cimetidine provides a good assessment in patients with various nephropathies and with non-insulin-dependent diabetes mellitus (NIDDM). The aim of this study was to compare cimetidine-aided GFR estimations using various creatinine assays. METHODS: In 30 outpatients with NIDDM GFR was measured as the urinary clearance of continuously infused [125I]iothalamate. Plasma creatinine concentration was analysed after oral cimetidine with an alkaline picrate (AP) method, with an enzymatic (PAP) assay and with HPLC. GFR estimations were calculated with the Cockcroft Gault formula (CG). RESULTS: AP creatinine concentrations were significantly higher than PAP or HPLC values. GFR estimations by AP (CG(AP) 66 +/- 19 ml/min/1.73 m2, mean SD) were significantly lower than GFR (89 +/- 30), whereas CG(PAP) (85 +/- 30) and CG(HPLC) (84 +/- 34 ml/min/1.73 m2) were not. Bland and Altman analysis showed a difference between CG(AP) and GFR of -22.4 +/- 17.7 ml/min/1.73 m2; this difference becomes larger when the GFR increases. The difference between CG and GFR was only -3.8 +/- 14.8 ml/min/1.73 m2 for PAP and -4.4 +/- 17.5 ml/min/1.73 m2 for HPLC, without any systematic difference. CONCLUSION: A good assessment of the GFR from plasma creatinine after cimetidine administration is possible when creatinine is measured with an enzymatic assay or with the less convenient HPLC method. The more widespread and cheaper alkaline picrate assay is not suitable for GFR-estimation.

Adult↗
PubMed1998

Day-to-day variability of fluid and solute transport in upright and recumbent positions during CAPD.

BACKGROUND: The effect of posture on peritoneal transport characteristics during CAPD is unpredictable because (1) although the capillary pressure is higher in the upright position, the intraperitoneal pressure is also elevated, and (2) the contact of dialysate with the subdiaphragmatic lymphatics is probably more extensive during recumbency. METHODS: In eight CAPD patients, six peritoneal permeability tests (4 h, glucose 2.27%, dextran 70 as volume marker) were performed within 2 weeks, while the body posture was either recumbent (3 tests) or upright (3 tests). In addition, intraperitoneal pressure measurements were done in the recumbent and upright positions. RESULTS: The intraperitoneal pressure, not corrected for the contribution of the hydrostatic column, was higher in upright position (12.6 +/- 0.8 mmHg, mean +/- SEM) than during recumbency (6.7 +/- 0.8; P < 0.0005). Net ultrafiltration rate was lower when upright: 0.96 +/- 0.09 ml/min/1.73 m2, compared to 1.14 +/- 0.12 in the supine position (P < 0.05). This was achieved because the effective lymphatic absorption rate was marginally higher and the transcapillary ultrafiltration rate was slightly lower in the upright position. The mass transfer area coefficient of creatinine, representing effective peritoneal surface area, decreased from 10.7 +/- 1.3 ml/min/1.73 m2 (recumbent) to 9.9 +/- 1.4 (upright; P = 0.08). The clearances of five serum proteins decreased more the higher the molecular weight. As a consequence the restriction coefficient was 2.07 +/- 0.09 (recumbent) vs 2.23 +/- 0.08 (upright; P = 0.06). Hence the intrinsic permeability to macro-molecules was higher during recumbency. The intraperitoneal pressure was correlated with the net ultrafiltration rate (r = -0.71, P = 0.05) only during recumbency. In upright position relations were found between the effective lymphatic absorption rate and the mass transfer area coefficients of low molecular solutes. The coefficients of variation of fluid and solute parameters were not different between both positions. CONCLUSIONS: It is concluded that the decrease in net ultrafiltration rate in the upright position is only small and probably caused by counteracting effects of a higher intra-abdominal pressure and the effect of gravity. The upright position also led to only small decreases in solute transport parameters.

Adult↗
PubMed1998

Estimation of the glomerular filtration rate in NIDDM patients from plasma creatinine concentration after cimetidine administration.

OBJECTIVE: Glomerular filtration rate (GFR) can be estimated in patients with renal disease from plasma creatinine concentration, age, sex, and body weight according to the formula of Cockcroft and Gault. The hypothesis that this method can be improved when tubular secretion of creatinine is inhibited by cimetidine was studied in NIDDM patients. RESEARCH DESIGN AND METHODS: In 30 outpatients with NIDDM and normo- (n = 10), micro- (n = 9), or macroalbuminuria (n = 11), GFR was measured as the urinary clearance during continuous infusion of 125I-labeled iothalamate. Plasma creatinine concentration was analyzed with an enzymatic assay before and after 800 mg t.i.d. oral cimetidine was given during a 24-h period. RESULTS: Plasma creatinine rose in all patients after cimetidine administration and, as a consequence, the clearance calculated with the Cockcroft-Gault formula fell. The ratio of this formula and GFR decreased from 1.16 +/- 0.20 to 0.97 +/- 0.16 (means +/- SD). This ratio tended to be smaller in the normo- (0.93) than in the micro- (0.98) and macroalbuminuric (1.00) groups. Also, 20 patients with a BMI < 30 kg/m2 had a smaller ratio than those with a BMI > 30 kg/m2 (0.92 vs. 1.07; P < 0.05). Bland and Altman analysis showed a difference of the Cockcroft-Gault formula and GFR of 12.0 +/- 17.4 ml.min-1 (1.73 m2)-1, which decreased to -3.8 +/- 14.8 ml.min-1.(1.73 m2)-1. The same analysis of 24-h creatinine clearance with urine collection and GFR showed larger standard deviations. CONCLUSIONS: GFR can be estimated in an acceptable way from plasma creatinine concentration after cimetidine administration in outpatients with NIDDM. Despite a nonsignificant underestimation in normoalbuminuric and overestimation in overweighted patients, this method is superior to 24-h creatinine clearance with outpatient urine collection.

Administration, Oral↗
PubMed1998

Contribution of tubular anion and cation secretion to residual renal function in chronic dialysis patients.

The clearance of organic ions by the tubules may contribute to the removal of uremic waste products in dialysis patients. The renal excretion of an exogenous anion p-aminohippurate (PAH) was investigated in 10 peritoneal dialysis patients and 10 hemodialysis patients during one clearance period and compared with the clearance of creatinine (Ccr) and inulin (CIn). The clearance period was 24 hours in the peritoneal dialysis patients and one interdialytic interval of 3 days divided in 4 parts [CPA-D] in hemodialysis patients. In peritoneal dialysis patients the renal clearance of total PAH (median 14.3 ml/min, range 3.8-33.0) exceeded the CIN (median 3.2 ml/min, range 1.6-11.2, p < 0.005) and Ccr (median 4.0 ml/min, range 1.7-15.0, p < 0.005). A positive correlation was found between the tubular clearances of creatinine (cationic pathway) and of total PAH (anionic pathway, r: 0.72, p <0.02). In hemodialysis patients the clearance of total PAH (CPA: median 2.0, range 0.8-9.6; CPD: median 3.8, range 1.7-15.4) also exceeded the clearance of inulin (CPA: median 1.5, range 0.2-3.4; CPD: median 2.7, range 0.9-4.4) in the beginning and the end of the interdialytic interval (p < 0.005). The CIN and the clearance of total PAH increased during the interdialytic interval, but the Ccr (CPA: median 2.2, range 0.4-8.9, CPD: median 2.9, range 1.2-4.6) remained stable. Thus, the change in tubular clearance of creatinine and PAH was opposite during the interdialytic interval: it increased for total PAH and decreased for creatinine. The CTPAH/CIN ratio in hemodialysis patients was lower than in peritoneal dialysis patients. In CPA it was median 1.6 (range 1.1-5.6, p < 0.05) and in CPD it was median 1.7 (range 1.1-5.0, p < 0.02) and in the peritoneal dialysis patients it was median 3.6 (range 1.5-9.1). We conclude that tubular clearances contribute to the residual renal function in dialysis patients, but the tubular handling of anions and cations in relation to the residual GFR is different between peritoneal and hemodialysis patients. A difference in clearance of organic acids caused by the dialysis techniques may be an explanation for the differences in clinical outcome between the two dialysis modalities.

Adult↗
PubMed1997

Clearance ratios of amylase isoenzymes and IgG subclasses: do they reflect glomerular charge selectivity?

The clearance ratios of endogenous plasma proteins with the same size but a different charge, such as the amylase isoenzymes and the immunoglobulin (Ig) G subclasses, have been used to assess glomerular charge selectivity in man. These proteins are, however, subject to tubular reabsorption. In this study we measured the IgG subclass/IgG clearance ratios for IgG1 (pI 8.0-9.5), IgG2 (pI 7.0-7.5) and IgG4 (pI < 6) in 6 healthy volunteers. Our results suggested a selective influence of tubular reabsorption: the IgG1/IgG clearance ratio was 0.68 +/- 0.14 (mean +/- SD) and lower than IgG2/IgG (2.02 +/- 1.06, p < or = 0.01). IgG4/IgG was 0.89 +/- 0.39. In addition, we studied the clearance ratios of pancreatic (PA, pI 7.0) and salivary amylase (SA, pI 5.9-6.4) and of IgG1 and IgG2 in 8 patients with minimal change nephrotic syndrome (MCNS), 11 patients recovering from acute tubular necrosis (ATN) and 9 healthy volunteers (controls). In MCNS glomerular charge selectivity is lost, while in recovering ATN tubular function is severely disturbed. The PA/SA clearance ratio was 3.25 +/- 0.89 in controls, reflecting intact glomerular charge selectivity. In MCNS patients the PA/SA clearance ratio had decreased to 1.21 +/- 0.23 (p < or = 0.001). In ATN patients the PA/SA clearance ratio was reduced as well: 1.55 +/- 0.41 (p < or = 0.001), although the aselective nature of the proteinuria and the modest albuminuria indicated intact glomerular charge selectivity. The IgG1/ IgG2 clearance ratio was 0.54 +/- 0.15 in controls, again suggesting preferential tubular reabsorption of IgG1. In MCNS patients the IgG1/IgG2 clearance ratio was 0.16 +/- 0.10 (p < or = 0.001); this probably reflects the relatively increased glomerular sieving of IgG2 when glomerular charge selectivity is lost. In ATN patients the IgG1/IgG2 clearance ratio was 1.07 +/- 0.47 (p < or = 0.001), which suggests a partial loss of preferential reabsorption of IgG1. It was concluded that the PA/SA clearance ratio is influenced by loss of tubular function and therefore does not reflect glomerular charge selectivity specifically. The IgG1/IgG2 ratio cannot be used to assess glomerular charge selectivity either because of the interference of selective tubular reabsorption of the subclasses. These findings put the assessment of glomerular charge using endogenous proteins in a new light and bring forward the necessity to interpret these ratios with the utmost cautiousness.

Adult↗
PubMed1997

Cimetidine improves GFR-estimation by the Cockcroft and Gault formula.

In some patients with renal disease 24-hour cimetidine aided creatinine clearances cannot equal GFR even after administration of the maximum daily dose of cimetidine. Short duration cimetidine aided creatinine clearances can equal GFR but are inconvenient for clinical use and can be inaccurate due to incomplete urine collection. We studied how accurately GFR can be estimated without the need to collect urine, by applying the Cockcroft and Gault formula (CCock) on a single plasma creatinine concentration, after oral administration of 3 x 800 mg cimetidine during the preceding 24 hours. GFR was measured as standard clearance, using continuous infusion of 125I-iothalamate. Nineteen patients with various renal diseases, plasma creatinine < 180 mumol/l and body mass index between 15 and 30 kg/m2 were included. After cimetidine administration, plasma creatinine values remained stable for 6 hours, despite rapidly decreasing plasma cimetidine values during the same period, in all 15 patients with GFR > 40 ml/min/1.73 m2. Tubular creatinine secretion was blocked completely in 14 of them. With cimetidine both accuracy and precision of the Cockcroft clearance improved: the mean (+/- SD) ratio of CCock to GFR decreased from 1.28 (+/- 0.21) to 0.98 (+/- 0.11) (p < 0.001) and the standard deviation of the difference (CCock-GFR) decreased from 9.23 to 7.07 ml/min/1.73 m2 (p < 0.05). With cimetidine the Cockcroft clearance correlated well with GFR (r = 0.974, p < 0.001) and this was as good as the correlation, between GFR and a 4-hour standard creatinine clearance (r = 0.972, p < 0.001). In conclusion, with a minimum of inconvenience, this method provides the clinician with accurate information on GFR for the outpatient follow-up of patients with a mild-to-moderate decrease in renal function, provided that no gross discrepancy between total bodyweight and muscle mass is present.

Adult↗
PubMed1997

Spectrum of diurnal rhythms in glomerular permeability in patients with membranous nephropathy.

BACKGROUND: Diurnal rhythms in proteinuria and selectivity index (SI) of proteinuria can vary from patient to patient with respect to phase and amplitude (A/M) and in some cases rhythms are absent. The aim of the present study was to relate this variability to a different pattern of diurnal rhythms in permselectivity of the glomerular capillary wall (GCW). METHODS: Ten patients with nephrotic syndrome due to membranous nephropathy were studied. Diurnal rhythmicity in size-dependent permselectivity of the GCW was determined by measuring 3-h fractional clearances of dextrans (30-90 A) over a period of 1 day. RESULTS: Four types of rhythmicity could be recognized. Type I and II only differed in the magnitude of the diurnal variability in glomerular transport through large pores (r2) and shunt pathway (omega). Both had normal rhythms in clearance of proteins and SI, but all rhythms were more pronounced in the patients with normal renal function and mild histological abnormalities (type II). Although type III also had a normal GFR and minor histological lesions, only transport through omega (and not through r2) showed a significant diurnal rhythm, which implied that this type did not have a normal rhythm in SI. The patients with advanced renal failure and extensive interstitial lesions neither had a rhythm in permselectivity nor had normal rhythms for proteinuria and SI (type IV). CONCLUSIONS: The type of rhythmicity in glomerular permeability corresponds well with the presence and phase of rhythms in clearance of proteins and in SI of the proteinuria.

Adult↗
PubMed1996

Circadian rhythm in glomerular transport of macromolecules through large pores and shunt pathway.

In previous studies we have demonstrated that the circadian rhythm in renal clearance of serum proteins is more pronounced than the variability in glomerular filtration rate, and that the highest day-night fluctuations are found for the largest proteins. To analyze whether additional circadian rhythmicity in size-selective glomerular transport could explain these phenomena, we measured renal clearances of inulin and dextrans in a range of 30 to 90 A over a period of one day and compared these data with renal clearance in proteins. Eight patients with nephrotic syndrome and a GFR > 60 ml/min and 6 healthy volunteers were studied during a protocol of bed rest and spaced protein and fluid intake. After administration of a loading dose, inulin and dextran were continuously infused. Blood and urine were sampled every three hours. In patients, but not in normals, fractional clearances of dextrans larger than 45 A showed a circadian rhythm with a peak in daytime and a close phase-relationship with the rhythm in GFR. The day-night differences were the most pronounced for the largest dextrans. Analysis of the day-night differences in a computer model showed circadian variability in transport through the shunt pathway and through large pores. These results can, to an important degree, explain our previous observations on circadian variability in renal clearance of proteins in patients with nephrotic syndrome.

Adult↗
PubMed1996

Fluid kinetics in CAPD patients during dialysis with a bicarbonate-based hypoosmolar solution.

The magnitude of transcapillary backfiltration by the colloidosmotic pressure within the peritoneal capillaries compared to the effective lymphatic absorption was investigated in continuous ambulatory peritoneal dialysis patients. This was done during a 4-hour dwell period, using a hypoosmolar dialysis fluid (280 mosm/kg H2O) in 8 patients and compared to 5 of these patients using a 1.36% glucose (GS; 324 mosm/kg H2O). The low molecular weight solute transport did not differ between the two solutions. The intraperitoneal dextran 70 concentration increased during the dwell with the hypoosmolar dialysis fluid (from 770 to 945 mg/l; p = 0.000002) and decreased with the GS (from 859 to 719 mg/l; p = 0.007). With the GS the transcapillary ultrafiltration was directed towards the abdominal cavity during the dwell period. With the hypoosmolar fluid, the transcapillary ultrafiltration was continuously directed towards the circulation. In this solution, the magnitude of transcapillary backfiltration due to colloidosmotic pressure within the peritoneal capillaries was 0.4 +/- 0.1 ml/min. In conclusion, intraperitoneal markers can be used in continuous ambulatory peritoneal dialysis patients for determination of effective lymphatic absorption and transcapillary fluid passage in both transport directions.

Adult↗
PubMed1996

Ranitidine has no influence on tubular creatinine secretion.

Oral cimetidine competitively inhibits tubular secretion of creatinine. We investigated the potential of oral ranitidine, a comparable H2-receptor antagonist, to block tubular creatinine secretion. In 10 healthy subjects, clearances of inulin and endogenous creatinine were simultaneously measured before and after administration of a single oral dose of ranitidine. In all subjects the effect of 300 mg ranitidine was studied; 7 subjects with high tubular secretion also participated in an additional study, when 1,200 mg ranitidine was administered. Neither dose of ranitidine caused a significant change in glomerular filtration rate measured by inulin clearance, or in mean plasma creatinine or in mean creatinine clearance. We conclude that a single oral dose of 300-1,200 mg ranitidine does not inhibit tubular secretion of creatinine in normal subjects, probably due to a lower affinity of ranitidine for the transport carrier at the luminal tubular membrane in comparison with cimetidine.

Adult↗
PubMed1996

Measurement of residual renal function in patients treated with continuous ambulatory peritoneal dialysis.

Renal function contributes markedly to the adequacy of continuous ambulatory peritoneal dialysis (CAPD). The best way to measure it in clinical practice has not been established. Ten stable CAPD patients with residual renal function were investigated to compare the GFR measured as inulin clearance (Cli) with the creatinine clearance (Clc), the urea clearance (Clu), and with 0.5(Clc + Clu). Thereafter, an analysis of whether the administration of cimetidine could improve the accuracy of these clearances was performed. Two clearance periods (CP) of 24 h were investigated. During CP-2, patients received 400 mg cimetidine twice daily, for a total dose of 1200 mg. Two h before the urine and dialysate collection period, inulin was administered iv. Calculations were done for each CP for Cli, Clc, Clu, Clc-Cli, the Clc/Cli ratio, and the tubular secretion of creatinine (TSc). No differences between CP-1 and CP-2 were present for urinary excretion of volume and solutes, and clearance rates of inulin and urea. The median TSc decreased from 0.71 mumol/min (range, -0.24 to 5.90) in CP-1 to 0.30 mumol/min (range, -0.18 to 0.64) in CP-2 (P < 0.05). Therefore, the median ratio of Clc/Cli decreased from 1.23 (range, 0.87 to 2.20) in CP-1 to 1.11 (range, 0.95 to 1.51) in CP-2 (P < 0.05). The median overestimation of the Cli in CP-1 by the Clc was 0.90 mL/min (range, -0.28 to 3.80) and by the 0.5(Clc + Clu) was 0.30 (range, -0.67 to 1.52). The median overestimation of Cli during cimetidine treatment in CP-2 was 0.43 mL/min (range, -0.21 to 1.20). The range, in differences between Cli and Clc, in CP-2 was smaller than that between Cli and 0.5(Clc + Clu) in CP-1. The difference between the clearance rate of inulin and creatinine or the combined clearance rate of urea and creatinine was not influenced by the magnitude of the average GFR. It can be concluded that the administration of cimetidine improved the accuracy of measuring the GFR with the Clc in CAPD patients.

Adult↗
PubMed1996

Effect of electric charge on the transperitoneal transport of plasma proteins during CAPD.

BACKGROUND: Controversy exists as to whether electric charges of plasma proteins influence their transport across the peritoneal membrane during CAPD. Fixed negative charges in the peritoneal membrane are diminished during peritonitis in rats. METHODS: Peritoneal clearances of 10 proteins and their isoforms were used to establish the relationship between peritoneal clearance and molecular weight. The observed protein clearances were compared with the predicted clearances based on molecular weight. Clearances of proteins with different charge but identical size were compared. Stable patients and peritonitis patients were compared. Results. Only the peritoneal clearance of lipase, LDH 4/5 and IgG3 were significantly different from the predicted values (P<=0.05). The peritoneal clearance of slightly anionic beta2 microglobulin (1072 microl/min) and cationic lysozyme (572 microl/min) showed no evidence for charge selectivity; neither did the peritoneal clearance of slightly anionic transferrin (86 microl/min) and highly anionic albumin (99 microl/min). The peritoneal clearance of IgG1, IgG2 and IgG4 were identical (32, 31 and 31 microl/min), despite their different charge. The peritoneal clearance of cationic LDH 4/5 was 137 microl/min and higher than the peritoneal clearance of neutral LDH 3 (97 microl/min, P=0.01) and LDH 1 (59 microl/min, P=0. 02). These results suggested charge selectivity; however in five additional patients during peritonitis the peritoneal clearance of LDH 4/5 increased to 10 times the peritoneal clearance of LDH 1. Local LDH isoenzyme release from the cells present in the dialysate was shown to be responsible in stable and peritonitis patients. Likewise, the higher peritoneal clearance of neutral pancreatic amylase (234 microl/min) compared to anionic salivary amylase (142 microl/min, P=0.03) could probably be attributed to local release of the former from the pancreas, as the peritoneal clearance of lipase (highly anionic) was higher than predicted and the difference remained during peritonitis. CONCLUSIONS: The peritoneal membrane constitutes a size- but probably not a charge-selective barrier for the transport of macromolecules between blood and dialysate during stable CAPD.

Adult↗
PubMed1996

Similarities in functional state of the kidney in patients treated with CAPD and hemodialysis.

Differences have been reported in the decline of residual renal function in patients on continuous ambulatory peritoneal dialysis (CAPD) and hemodialysis (HD), but it is unknown whether the urinary handling of water and solutes is similar in these patient groups. Ten CAPD patients with residual renal function were investigated during a clearance period (CP) of 24 hours, and 11 HD patients were investigated during one interdialytic interval of three days. In CAPD patients the urinary volume excretion was 0.65 +/- 0.31 mL/min (mean +/- SD), and the inulin clearance was 3.85 +/- 2.82 mL/min. A negative correlation was found between the peritoneal net ultrafiltration rate and both the urinary volume excretion rate (r = -0.80, p < 0.01) and the fractional sodium clearance (r = -0.69, p < 0.05). In HD patients the urinary volume excretion increased from 0.36 +/- 0.36 mL/min during the initial eight hours of CP (HD-A) to 0.64 +/- 0.29 mL/min during the last ten hours of CP (HD-D, p < 0.05), and the inulin clearance increased from 1.9 +/- 1.3 (HD-A) to 2.9 +/- 1.1 (HD-D, p < 0.005). The fractional sodium clearance increased from 8.5 +/- 5.7% (HD-A) to 14.4 +/- 9.0% (HD-D, p < 0.05). It can be concluded that the fractional excretion of volume and fractional clearance of solutes were similar in patients treated with CAPD and hemodialysis. The most important regulating factor seems to be the volume status influenced by volume removal by peritoneal net ultrafiltration in CAPD patients, and volume expansion during the interdialytic interval in hemodialysis patients.

Adult↗
PubMed1995

Treatment of proliferative lupus nephritis with methylprednisolone pulse therapy and oral azathioprine.

OBJECTIVE: To evaluate the treatment of proliferative lupus nephritis with methylprednisolone pulse therapy and oral azathioprine. PATIENTS AND METHODS: Eighteen patients with severe proliferative lupus nephritis (Class III, IV or Vd according to criteria of the World Health Organization) were treated with intravenous methylprednisolone (MP) pulse therapy in combination with a low oral maintenance dose of prednisone (20 mg) and azathioprine (2 mg/kg). Thirteen patients (Group I) had a recent onset of clinical manifestations of nephritis at referral (mean and median 4 months). Five patients (Group II) had clinical signs of nephritis for a long time (median 4 years, mean 5 years) and were referred because of progressive renal failure. The mean plasma creatinine in Group I was 109 mumol/l with a mean GFR of 58 ml/min, the mean plasma creatinine in Group II was 284 mumol/l with a mean GFR of 12 ml/min. Renal histology in Group II was characterized by severe chronic damage (chronicity index 8-10). RESULTS: Short-term and long-term effects of treatment were excellent in Group I. The mean plasma creatinine was 68 mumol/l with a mean GFR of 102 ml/min at a mean follow-up of 7 years, median 4 years (range 1-15 years). All patients in Group II needed renal replacement therapy after a mean follow-up of 2.6 years, median 2 years (range 0-8 years). Major side-effects of treatment were only seen twice. CONCLUSION: Methylprednisolone pulse therapy in combination with low oral maintenance doses of prednisone and oral azathioprine is an effective and safe treatment for patients with severe active proliferative lupus nephritis. In patients with extensive irreversible lesions, this treatment has no or only a temporary effect.

Adolescent↗
PubMed1995

Dialysis treatment in patients with rheumatoid arthritis.

The results of dialysis treatment in 24 rheumatoid arthritis patients, 20 chronic rheumatoid arthritis (RA) and 4 juvenile rheumatoid arthritis (JRA), were analysed. Presence of secondary amyloidosis, renal function, morbidity and survival were examined. Amyloidosis was present in 13 patients. Especially among amyloidosis patients, renal function declined rapidly in the last year before dialysis started. On average, 63 days per patient-year were spent in the hospital, 58% was dialysis-related, mainly due to vascular access problems. Hospitalization was even more widespread in amyloidosis patients (79 days, 72% dialysis-related). Median survival in RA patients with amyloidosis was 11 months; in RA patients without amyloidosis this was 29 months. Two-year survival was only 1 out of 10 for the RA amyloidosis patients; for the RA non-amyloidosis patients this was 5 out of 6 (p < 0.01). Cardiovascular causes of death were most frequent. In conclusion, high morbidity and low survival make RA patients with amyloidosis a high-risk group on renal replacement therapy.

Adult↗
PubMed1995

Time course of inulin and creatinine clearance in the interval between two haemodialysis treatments.

BACKGROUND: Urinary volume of haemodialysis patients with residual renal function increases during the interdialytic interval. The contribution of GFR to this change in water and solute excretion has not been quantified in detail. The creatinine clearance (Clc) as a determinant of the GFR may overestimate GFR caused by the tubular secretion of creatinine. Cimetidine has been used to inhibit the secretion of creatinine in non-dialysed patients. No data are available on its usefulness in haemodialysis patients. METHODS: Two identical interdialytic intervals (DI) of 3 days (DI-1, DI-2) were investigated in 11 patients. The interval between DI-1 and DI-2 was 1 week. During DI-2 cimetidine 800 mg daily was administered. Each DI was divided in four urine-collection periods. RESULTS: The water and solute excretion in DI-1 and DI-2 were similar. Urinary production increased from 0.37 +/- 0.30 ml/min to 0.66 +/- 0.33 ml/min (P < 0.05), inulin clearance (Cli) increased from 1.8 +/- 1.1 ml/min to 2.7 +/- 1.2 ml/min (P < 0.05), fractional sodium excretion from 9.0 +/- 5.7% to 14.5 +/- 9.0% (P < 0.05). In contrast to Cli the Clc showed no increase during the interdialytic interval both in DI-1 and DI-2. The overestimation of GFR by creatinine (Clc-Cli) decreased during DI-1 from 1.35 +/- 1.69 ml/min to 0.26 +/- 0.60 (P < 0.05) and during DI-2 from 1.01 +/- 1.33 ml/min to 0.10 +/- 0.67 (P < 0.01). The ratio Clc/Cli decreased during DI-1 from 1.78 +/- 0.53 to 1.09 +/- 0.19 (P < 0.01) and during DI-2 from 2.02 +/- 1.13 to 1.05 +/- 0.30 (P < 0.01). All parameters were not different between the comparable days of DI-1 and DI-2. CONCLUSION: We conclude that the urinary volume in the interdialytic interval is directly related to changes in GFR. During the interdialytic interval GFR increased and tubular secretion of creatinine decreased. The administration of cimetidine did not improve the accuracy of Clc as a measurement of GFR in end-stage renal failure.

Adult↗