Long-term evolution of the mineral metabolism after renal transplantation: a prospective, single-center cohort study

BACKGROUND

Abnormalities in bone and mineral metabolism are common after renal transplantation (RT) but information on their long-term time course is scarce.

OBJECTIVES

(1) Evaluate the time course of biochemical parameters of bone and mineral metabolism over 60 months after RT; (2) identify predictors for persistent hyperparathyroidism (HPT).

DESIGN

Prospective, longitudinal, single-center cohort study.

METHODS

We determined serum levels (mean values ± standard deviations) of intact parathyroid hormone (iPTH), calcium (Ca), phosphorus (P), magnesium (Mg), alkaline phosphatase (APh), calcitriol, and creatinine (Cr) preoperatively as well as 6, 12, 24, 36, 48, and 60 months after cadaveric RT in 49 patients. We in addition recorded demographic, clinical, and therapeutic data.

RESULTS

Pretransplantation iPTH stabilized from 194.2 ± 273.5 to 71.5 ± 50.7 ng/L at 6 months. Serum Ca (9.5 ± 1.1 mg/dL) and APh (81.9 ± 42.1 U/L) did not change. Baseline serum P (5.7 ± 1.8 mg/dL) and serum Mg (2.4 ± 0.4 mg/dL) decreased to normal ranges from month 6 onward. Low baseline calcitriol (22.4 ± 21.8 pmol/L) normalized slowly by 12 months (95.4 ± 46.7 pmol/L). Stable graft function (53.2 ± 15.8 mL/min) was achieved from 6 months onward. By 60 months, 26.5% of patients had a serum Ca above 9.8 mg/dL and serum P below 2.7 mg/dL; 22.4%, an Mg below 1.7 mg/dL and 8.2%, a serum iPTH more than 2.5-fold the upper limit of normal. Upon multiple regression analyses the iPTH at 60 months was influenced by a dialysis duration ≥ 2 years (β = 0.259, P = .003), body mass index > 25 kg/m(2) (β = 0.257, P = .006), baseline iPTH (β = 0.182, P = .036), serum Cr (β = 0.268, P = .002) and Mg (β = -0.242, P = .006).

CONCLUSIONS

Hypercalcemia, hypophosphatemia, hypomagnesemia, and elevated iPTH persist in a subset of post-RT patients. Pretransplantation iPTH and obesity, dialysis duration, and posttransplant serum creatininemia and hypomagnesemia independently contribute to persistent HPT.

Reduced-exposure cyclosporine is safe and efficacious in de novo renal transplant recipients treated with enteric-coated mycophenolic acid and basiliximab

BACKGROUND

The lower limit of exposure to calcineurin inhibitors has not yet been established in de novo renal transplant patients receiving mycophenolic acid therapy with basiliximab.

METHODS

A 12-month, multicenter, randomized, open-label trial was carried out in which de novo renal transplant patients received enteric-coated mycophenolate sodium, cyclosporine microemulsion, steroids and basiliximab. Patients were randomized to receive standard-exposure (n = 45) or reduced-exposure (n = 44) cyclosporine, based on differing C2 target ranges, after the first month post-transplant.

RESULTS

Cyclosporine exposure gradually increased over the first month and was lower than previously recommended. Mean calculated creatinine clearance (primary end-point) was similar in the standard-exposure and reduced-exposure groups at month 6 (55.3+/-3.2 ml/min and 61.5+/-3.7 ml/min respectively, n.s.). There were 4 deaths but no death-censored graft losses, resulting in 95.5% patient and graft survival at one year in both groups. At 6 and 12 months, the incidence of biopsy-proven acute rejection was 17.8% and 17.8% in the standard-exposure group, and 13.6% and 15.9% in the reduced-exposure group. Adverse events were similar between treatment groups. Exploratory analyses could not identify a lower limit for the optimal CsA exposure range, but results suggested that high exposure at one year was associated with deteriorating renal function.

CONCLUSIONS

These results indicate that enteric-coated mycophenolate sodium with reduced-exposure cyclosporine, steroids and basiliximab induction has an excellent therapeutic effect and is safe in de novo kidney transplant recipients. Lower C2 targets than previously recommended, particularly early post-transplant, do not appear to be associated with compromised efficacy.

Severe diarrhea in renal transplant patients: results of the DIDACT study

Diarrhea is common in transplant recipients. While the majority of cases are mild and transient, some are severe and prolonged, which can threaten graft survival through dehydration. While it is known that some immunosuppressive agents can elicit diarrhea, there does not appear to be any consensus on the role that other nonimmunosuppressive causes can play in transplant patients. The aim of the present open, nonrandomized, multicenter study was to identify nonimmunosuppressive factors involved in severe diarrhea in renal transplant patients. Patients (n = 108) with severe diarrhea (>/=3 stools/day for >/=7 days) were enrolled from 16 Belgian transplant centers. Patients were diagnosed according to an agreed flowchart that consisted of identification of possible infections, followed by changes in empirical and immunosuppressive treatment. Approximately 50% of patients experienced resolution of severe diarrhea following treatment for infections, dietary problems or diarrhea-causing concomitant medications. In conclusion, a large proportion of the severe diarrhea observed in renal transplant recipients is not associated with immunosuppressive therapy and can be treated through anti-infectives, changes to concomitant medication and other empirical treatments. Correct diagnosis of the cause of severe diarrhea in such patients should help to protect graft survival in transplant recipients.

[Atypical Cogan's syndrome. Based on a case]

Cogan's syndrome is a systemic inflammatory disease that associates typical (interstitial keratitis) and atypical (such as anterior uveitis) ocular manifestations to vestibulo-auditory dysfunction. It has also a systemic vascular association of vasculitis type. We report a case of a 64 years old woman who presented an atypical form with anterior uveitis.

Relapsing ascites and uremia due to urinary bladder leakage

A 62-year-old female was admitted for a new episode of ascites, complicated by uremia. She had been treated 6 years earlier for bladder cancer with partial cystectomy and postoperative radiotherapy. At the work-up for both previous episodes of ascites, 6 and 24 months earlier, no definite diagnosis was made, and each time the ascites disappeared spontaneously. Also, at the third episode, the uremia resolved. Finally, explorative laparoscopy demonstrated urinary leakage from the superior portion of the bladder. This feature of vanishing and relapsing ascites is explained by intermittent covering by overlying abdominal structures and subsequent spontaneous healing. The pseudo-renal failure is caused by reabsorption of urine through the peritoneum. Only nine cases of recurring ascites and eight cases of bladder perforation after radiotherapy have been described in the literature.

Hydroxyethyl starch does not impair immediate renal function in kidney transplant recipients: a retrospective, multicentre analysis

BACKGROUND

The effect of hydroxyethyl starch (HES) on early allograft function was examined retrospectively in a cohort of 119 renal transplantations realized by local organ exchange between four cooperating centres.

METHODS

After exclusions, 109 transplant procedures were subdivided in three groups according to donor colloid loading: (i) HS-group (Haes steril 6%, mean volume (SD): 979 (946) ml, n = 20); (ii) PS-group [Plasmasteril, mean volume (SD): 769 (411) ml, n = 16]; and (iii) control group (gelatin albumin, n=73).

RESULTS

Delayed graft function (DGF), defined as the need for dialysis during the first post-transplant week, occurred in 3/20 (15%) cases in the HS-group, in 5/16 (31%) cases in the PS-group and in 14/73 (19%) cases in the control group (P = 0.450). Uni- and multivariate analysis revealed older donor age (P = 0.001) and kidney preservation with histidine-tryptophan-ketoglutarate (HTK) (P = 0.001) as the only factors associated with a higher incidence of DGF.

CONCLUSIONS

Renal function as measured by daily serum creatinine concentration and 24 h urinary output up to 14 days post-transplantation in the HS-group was comparable with that of controls. The higher serum creatinine observed during the first seven post-transplant days in the PS-group could be related to higher donor age and haemodynamic instability, and recipient male preponderance, rather than to HES itself.

Fixed low-dose perindopril-indapamide combination in hypertensive patients with chronic renal failure

The angiotensin converting enzyme inhibitor perindopril and the diuretic indapamide have been shown to be effective antihypertensive agents in patients with chronic renal failure. A fixed low-dose combination of these two agents has been proposed in the treatment of hypertension. We evaluated this combination in 26 patients with mild to moderate essential hypertension and mild to severe chronic renal failure that did not require dialysis. This was a multicenter, open trial consisting of a 2-week single-blind placebo washout period followed by 12 weeks of active treatment. At week 0, the patients received 2 mg perindopril/0.625 mg indapamide once a day or every other day, with the possibility of dosage adjustment to perindopril 4 mg/indapamide 1.25 mg at week 2, week 4, or week 8. A pharmacokinetic analysis using a population pharmacokinetic approach was performed at week 8. Twenty-three patients completed the 12-week study, at which time 14 patients were receiving 2 mg perindopril/0.625 mg indapamide daily, three were receiving 2 mg perindopril/0.625 mg indapamide every other day, and six perindopril 4 mg/indapamide 1.25 mg. Blood pressure readings (supine) decreased from 170.4+/-19.2 / 101.5+/-6.7 mm Hg before active treatment to 146.5+/-19.7 / 86.5+/-10.6 mm Hg at the end of treatment (P < .0001). Pharmacokinetic analysis showed that for indapamide and perindoprilat (the active metabolite of perindopril) the area under the curve (AUC24) increased with the severity of renal failure. No interaction was noted between the two drugs. Mean serum creatinine and sodium and serum potassium levels remained stable during the study. Impairment of renal function occurred in one patient and was considered unrelated to treatment. We conclude that a fixed low-dose perindopril-indapamide combination as first-line treatment has a good safety/efficacy ratio in hypertensive patients with chronic renal failure.

Prevalence of histological beta2-microglobulin amyloidosis in CAPD patients compared with hemodialysis patients

BACKGROUND

The prevalence of beta2-microglobulin amyloidosis (Abeta2m) in patients on continuous ambulatory peritoneal dialysis (CAPD) is unknown.

METHODS

We prospectively obtained a median of 2 (range 1 to 4) joint samples from 26 CAPD patients aged 44 to 93 (median 73) years at post-mortem evaluation after 4.5 to 126 (median 27) months solely on CAPD (N = 19) or primarily on CAPD (that is, < or = 10% and < or = 1 year of renal replacement therapy time on other modalities; N = 7). The diagnosis of Abeta2m rested on Congo red staining (typical birefringence) and positive immunostaining of amyloid deposits by a monoclonal anti-beta2m antibody.

RESULTS

Abeta2m was diagnosed in 8 of 26 patients (31%). Prevalence ranged from 20% (2 of 10 patients) within < or = 24 months CAPD to 30% (3 of 10 patients) after 24 to 48 months and 50% (3 of 6 patients) after 49 to 126 months (P = 0.11). The prevalence of Abeta2m was similar in patients without or with one or more peritonitis episodes. No significant difference in prevalence (P = 0.118) was found between CAPD patients (8+/26; 31%) and hemodialysis patients (13+/26; 50%) carefully matched for time on dialysis and age at the onset of dialysis.

CONCLUSIONS

The prevalence of histological Abeta2m reaches 31% after a median duration of 27 months of CAPD. This prevalence is not significantly different from that observed in a group of HD patients matched for age and dialysis duration.

Hemophagocytic syndrome and T-cell lymphoma after kidney transplantation: a case report

Lymphoma in immunocompromised transplant patients is a feared cause of morbidity and mortality. Superimposed on the lymphoma and the transplantation immunosuppression is a rare condition: hemophagocytic syndrome (HS). HS is characterized by fever, hepatosplenomegaly and lymphadenopathy, skin rashes, jaundice, coagulopathy, and phagocytosis of blood elements with pancytopenia. Here we describe a rare but fatal case of a kidney transplant patient who developed T-cell lymphoma and HS, without evidence of EBV replication. A short review of the diagnosis, treatment, and prognosis of HS is given.

Histological prevalence of beta 2-microglobulin amyloidosis in hemodialysis: a prospective post-mortem study

The histological prevalence of beta-2 microglobulin amyloidosis (A beta 2m) was evaluated in a prospective study of joint samples obtained at autopsy in 54 patients on hemodialysis (HD) for 2 to 163 (median 47) months, aged 20 to 80 (median 63) years at HD onset. Carpal tunnel syndrome surgery or radiological signs of A beta 2m were present in 2 and 4% of them, respectively. A control group of 34 patients without end-stage renal disease, autopsied during the same period was used as a reference. The 153 sampled joints (1 to 8, median 2 per patient) were sternoclavicular joints (N = 77), shoulders (N = 35), knees (N = 28), others (N = 13). A beta 2m was diagnosed (positive Congo red with typical birefringence and positive immunostaining of deposits for beta 2m) in 26 of 54 (48%) patients. Prevalence reached respectively 21%, 33%, 50%, 90% and 100% within two years, after 2 to 4 years, 4 to 7 years, 7 to 13 years and more than 13 years HD. The calculated sensitivity of the various joints for A beta 2m detection is significantly higher (P < 0.03) for sternoclavicular joints (97%) and knees (91%) than for shoulders (57%). Multivariate stepwise logistic regression with discriminant analysis identified both HD duration (P = 0.0008) and age at HD onset (P = 0.0093) but not diabetic nephropathy (P = 0.23) or gender (P = 0.25) as independent risk factors for A beta 2m. The probability of joint A beta 2m was quantitated as a function of age and HD duration. In conclusion, A beta 2m may be observed in the large joints early after HD onset. Overall prevalence reaches 48% of the patients on HD for a median of 47 months. It is much higher than that reported on the basis of clinical or radiological evidence. The sternoclavicular and knee joints are more frequently (P < 0.03) involved than the shoulder. The easily accessible sternoclavicular joint therefore appears to be the best site for the early detection of A beta 2m. Both HD duration and age at HD onset, but not diabetic nephropathy, are independent risk factors for A beta 2m.

Effect of treatment with 1.25 and 1.75 mmol/l calcium dialysate on bone mineral density in haemodialysis patients

The effect of two different dialysate solutions with a calcium concentration of 1.25 and 1.75 mmol/l was evaluated in 14 patients, using a cross-over design. Patients were treated with each solution during a period of 6 months. Treatment with calcium supplements, vitamin D and aluminium hydroxide was adapted weekly, according to the results of blood chemistry. PTH, SAP, and ionized calcium were determined monthly, bone density with DXA and QCT before and after 6 months of treatment. During treatment with both 1.25 and 1.75 calcium dialysate (cad), the control of serum calcium and phosphate was similar. PTH did not change during either treatment. SAP decreased during treatment with 1.75, but remained stable with 1.25 mmol/l cad. Bone density evaluated with DXA remained unchanged during both treatments. QCT measured bone density increased from 101.29 +/- 13.50 to 106.79 +/- 13.14 mg/ml in the 1.75 cad group, while it did not vary in the 1.25 cad group, (107.75 +/- 13.48 versus 108.97 +/- 13.40 mg/ml). It is concluded that lowering the calcium content of the dialysate does not negatively influence the control of serum calcium and phosphate, nor does it aggravate hyperparathyroidism when vitamin D is administered simultaneously. Under the present conditions, osteopenia and possibly bone mineralization improve only in the group dialysed with 1.75 Ca.

Comparison of perindopril and amlodipine in cyclosporine-treated renal allograft recipients

The objective of this study was to compare the antihypertensive efficacy and influence on renal function of perindopril and amlodipine in cyclosporine-treated renal allograft recipients with mild to moderate hypertension. We conducted a randomized, double-blind, double-dummy crossover trial in ambulatory patients. Four phases were conducted: 2 weeks on placebo, 8 weeks of maintenance (perindopril or amlodipine), and 2 weeks of washout between treatment periods. Ten hypertensive patients with stable renal allograft function transplanted more than 6 months previously and receiving cyclosporine as part of their immunosuppressive regimen were studied. The patients were allocated to perindopril (2 or 4 mg/d) and amlodipine (5 mg/d) in a random sequence. If office diastolic pressure was greater than or equal to 90 mm Hg after 4 weeks, the dosage was doubled and continued for another 4 weeks. The main outcome measures were office and 24-hour ambulatory blood pressure changes after 8 weeks of active treatment and treatment and time effect on glomerular filtration rate and effective renal plasma flow. Perindopril and amlodipine were equally effective in lowering office blood pressure and similarly efficacious for the 24-hour period of the day. Neither drug affected glomerular filtration rate or effective renal plasma flow. Both agents demonstrated equivalent capacity (time x treatment, P = .955) to reverse renal vascular resistance (amlodipine from 0.35 +/- 0.02 to 0.30 +/- 0.02 mm Hg/mL per minute per 1.73 m2; perindopril from 0.36 +/- 0.03 to 0.32 +/- 0.01) (time effect of all treatments together, P = .043).(ABSTRACT TRUNCATED AT 250 WORDS)

Legionnaires' disease and acute renal insufficiency: report of a case and review of the literature

We report the case of a 73-year-old man, who developed acute renal failure in association with a Legionella pneumophila serotype 1 pneumonia. Renal biopsy revealed a tubulointerstitial nephritis. Treatment with erythromycin, rifampicin and haemodialysis resulted in a clinical resolution of the pulmonary and renal syndromes.

Pharmacokinetics of rilmenidine in patients with chronic renal insufficiency and in hemodialysis patients

The pharmacokinetics of rilmenidine (1 mg orally) was studied in 3 groups of patients with stable chronic renal insufficiency. This was an open, single-blind study following a single administration, and after 15 days of treatment. Group 1 included 11 patients with a creatinine clearance between 15 and 80 mL/min. Group 2 included 17 patients with a creatinine clearance < 15 mL/min. Group III included 10 hemodialysis patients. In patients with chronic renal failure, total plasma clearance and renal clearance of rilmenidine decreased; terminal half-life was 30-42 hours, which is clearly longer than previous values achieved in healthy volunteers. After repeated administration (1 mg daily in group 1, 1 mg every other day in group 2, 1 mg at the end of each dialysis session in group 3), the area under the curve was significantly increased, corresponding to drug accumulation. The steady state was reached after 6 days in patients in group 1 and after 8 days in patients in group 2. The pharmacokinetics of rilmenidine was linear since the terminal elimination half-life and renal clearance were not significantly different after single and repeated administration of rilmenidine. A positive correlation was found between rilmenidine total plasma clearance and creatinine clearance, and between rilmenidine renal clearance and creatinine clearance. Mean rilmenidine hemodialysance was 85 mL/min, that is, 26% of the rilmenidine renal clearance value achieved in healthy volunteers (330 mL/min). Thus, the following dosage schedule can be proposed. In patients whose creatinine clearance ranges between 15 and 80 mL/min, a 1 mg dose every day can be recommended.(ABSTRACT TRUNCATED AT 250 WORDS)

Pharmacokinetics of linsidomine (SIN 1) after single and multiple intravenous short infusions in patients with renal insufficiency

Pharmacokinetic measurements were performed in two groups of patients with coronary heart disease (CHD) after single and multiple dosing of 2 mg linsidomine (SIN 1). The drug was administered by intravenous short time infusion in 12 CHD-patients with renal insufficiency (RI group, Clcr: 11 +/- 6 ml/min) and in 12 CHD-patients with normal kidney function (control group, Clcr: 88 +/- 22 ml/min). The measurement of plasma concentration time courses of total SIN 1C (SIN 1 + SIN 1C) was found to be suitable for an estimation of the SIN 1C related half-life of the terminal phase (t50% = 1.5 +/- 0.5 h), as SIN 1 was eliminated from plasma rapidly (t50% = 12 to 20 min). Furthermore, the mean total SIN 1C plasma profiles were equal after single and multiple administration of the drug giving evidence that SIN 1C is not accumulating during repetitive dosing of SIN 1 in patients with renal disease. The mean maximum renal fraction of total SIN 1C excretion of RI-subjects (fe = 0.8 +/- 0.8% of dose) was significantly different from the corresponding mean value of the control group (fe(N) = 5.8 +/- 5.1% of dose). No differences were found for fe and fe(N) between day 1 and day 4. As SIN 1 is degraded in plasma very rapidly and as SIN 1C is cleared mainly extrarenally, any restrictions concerning repetitive SIN 1 dosage regimen should not be considered for CHD-patients with renal failure.

The association of bronchiolitis obliterans organizing pneumonia, systemic lupus erythematosus, and Hunner's cystitis

An 83-year-old woman with histologically confirmed Hunner's cystitis presented with persistent fever, progressive dyspnea, and pulmonary patchy infiltrates. A transbronchial biopsy specimen revealed bronchiolitis obliterans organizing pneumonia. She progressively had development of renal insufficiency, due to systemic lupus erythematosus, proved by renal biopsy specimen. She recovered under corticosteroid treatment, but irreversible renal failure made long-term hemodialysis necessary.

Dialysis in patients over 65 years of age

In 44 patients with end-stage renal disease, 24 on hemodialysis and 20 on CAPD, the survival was calculated using the life table method. Median survival for CAPD was 19 months and for hemodialysis 47 months. Using Cox's proportional hazards model, treatment modality and performance score were significant determinants of survival. Performance score was influenced by age and kidney disease. When survival was analyzed separately for patients with a good or a bad performance score, the survival was better in the hemodialysis group only in patients with a bad score (ECOG 3 and 4). Patients with a good score had similar prognoses, irrespective of treatment modality.

Renal failure in sarcoidosis. Case report of granulomatous interstitial nephritis and review of the literature

We present the case of a 74-year-old male patient with granulomatous nephritis due to sarcoidosis. We review the different possibilities of renal involvement in sarcoidosis and treatment modalities are discussed.

The pharmacokinetics of perindopril and its effects on serum angiotensin converting enzyme activity in hypertensive patients with chronic renal failure

1. Perindopril, an orally active angiotensin converting enzyme inhibitor, was given to 23 hypertensive patients with stable chronic renal failure for 15 days. The dose of perindopril was 2 or 4 mg once a day according to the degree of renal failure. The creatinine clearance of the patients ranged from 6 to 67 ml min-1 1.73 m-2. The pharmacokinetics of perindopril and perindoprilat, its active metabolite, were studied after acute and chronic administration of perindopril. 2. The drug was well tolerated and creatinine clearance was unaltered by treatment. 3. In both groups, steady-state was reached within 3 days of chronic treatment. 4. After both acute and chronic drug administration renal impairment had no effect on perindopril pharmacokinetics but the pharmacokinetics of perindoprilat were altered significantly. After chronic administration the serum accumulation ratio was 1.81 in patients with mild renal failure and 5.35 in patients with severe renal failure. Chronic administration did not modify the renal clearance of perindoprilat nor its elimination half-life. 5. A significant correlation between the renal clearance of perindoprilat and creatinine clearance was observed (r = 0.87 first dose, r = 0.83 last chronic dose). 6. A non-linear relationship between serum perindoprilat concentration and inhibition of angiotensin converting enzyme was described by a modified Hill equation. Values of IC50 were 1.11 +/- 0.07 micrograms I-1 (mean +/- s.d.) in patients with severe renal failure and 1.81 +/- 0.20 micrograms l-1 in patients with moderate renal failure. Chronic administration increased maximal inhibition and decreased the time to maximal inhibition only in patients with severe renal failure.(ABSTRACT TRUNCATED AT 250 WORDS)

Pharmacokinetics of intravenous and oral chlordesmethyldiazepam in patients on regular haemodialysis

The pharmacokinetics of a single 2 mg IV dose of chlordesmethyldiazepam has been studied in 11 patients with renal failure on regular haemodialysis and in 11 age-matched healthy controls. The kinetics was also examined after a single 2 mg oral dose in 6 of the 11 renal failure patients. After intravenous administration the kinetics of total chlordesmethyldiazepam in renal patients and controls were the same. The unbound fraction of the drug in renal patients was higher (5.5%) than in controls (2.9%). Correction for differences in protein binding revealed a reduced apparent volume of distribution (47 vs. 140 l.kg-1) and a reduced clearance (5.0 vs. 10.5 ml.min-1.kg-1) in the patients. The systemic availability of oral chlordesmethyldiazepam was good (82%) despite a relatively slow absorption rate.

Evaluation of platelets and hemostasis during hemodialysis with six different membranes

Hemodialysis induces thrombocytopenia and activation of coagulation. The severity of this reaction depends on the kind of membrane. In this study, we present the results of determination of platelet count, and of different factors of coagulation in 10 stable dialysis patients. Measurements were performed at the start and after 15 and 45 min of dialysis. Samples were taken before and after the dialyzer. All 10 patients were treated consecutively and in a random order during 14 days with the following membranes: polyacrylonitrile (Filtral 12, Hospal), hemophan (GFS 120 Plus, Gambro, and Bio-Nephros HF Andante, Organon), polysulfone (F6, Fresenius), cuprammonium (AM50-BIO, Asahi) and cellulose acetate (Duo-Flux, Cordis-Dow). The cellulose acetate membrane induced a small but significant drop of mean platelet count [results are mean (SEM)]: from 245,000 (17,000) to 224,000 (16,000)/microliters after 15 min. With the same membrane a dramatic increase after 15 min was noted of 6-keto-PGF1 alpha from 56.3 (9) to 146.7 (35.7) pg/ml. The other membranes did not influence significantly prostanoid levels and platelet count. During dialysis no significant changes of fibrinopeptide A (FPA) and von Willebrand factor (VWF) were observed. Nevertheless, predialysis FPA and beta-thromboglobulin (beta TG) concentrations were lowest after 14 days of treatment with cellulose acetate and polyacrylonitrile membranes. It is concluded that the activation of coagulation depends on the membrane used. The activation may be dominated by one single system (e.g. prostanoids). The different predialysis concentration of some of the factors suggests interference of the dialysis membrane with the activation of coagulation during the interdialytic period.

Iron and total iron-binding capacity in serum of patients receiving iron-dextran: Kodak Ektachem methodologies, spectrophotometry, and atomic-absorption spectrometry compared

We compared the analytical performance of the Kodak Ektachem XR700 assays of iron (Fe) and total iron-binding capacity (TIBC) with that of a conventional ferrozine assay (performed with a Cobas-Bio) and occasionally with that of atomic-absorption spectrometry (AAS). The correlation was modest between Kodak and Cobas-Bio concentrations of Fe in serum (r = 0.79). Multiple outliers were noticed in samples from hemodialysis patients, with Cobas values exceeding those of Kodak by as much as 26 mumol/L. These intermethod differences were not dissipated by dialysis, but were invariably accompanied by an even higher total Fe content of the serum as judged by AAS (20 to 80 mumol/L higher). TIBC values by Kodak and Cobas-Bio were highly correlated (r = 0.99); again, the Cobas-Bio results exceeded those by Kodak in some hemodialysis patients, but always for samples with higher Fe concentrations by the Cobas-Bio. By AAS, the TIBC values of these patients also exceeded those by Kodak, to about the same extent as observed for serum Fe. These intermethod differences in Fe and TIBC were seen only in patients who had received an intravenous Fe-dextran (Imferon) injection two to three days before blood sampling but could be generated in vitro by adding Imferon to serum from normal controls. Less than 6% of dextran-bound Fe is measured as Fe by Kodak, as opposed to 20-30% by Cobas-Bio and 89-120% by AAS. We conclude that the Kodak Fe slides are superior to liquid reagents, by exclusively measuring protein-bound circulating Fe pools.

Iron and total iron-binding capacity in serum of patients receiving iron-dextran: Kodak Ektachem methodologies, spectrophotometry, and atomic-absorption spectrometry compared

We compared the analytical performance of the Kodak Ektachem XR700 assays of iron (Fe) and total iron-binding capacity (TIBC) with that of a conventional ferrozine assay (performed with a Cobas-Bio) and occasionally with that of atomic-absorption spectrometry (AAS). The correlation was modest between Kodak and Cobas-Bio concentrations of Fe in serum (r = 0.79). Multiple outliers were noticed in samples from hemodialysis patients, with Cobas values exceeding those of Kodak by as much as 26 mumol/L. These intermethod differences were not dissipated by dialysis, but were invariably accompanied by an even higher total Fe content of the serum as judged by AAS (20 to 80 mumol/L higher). TIBC values by Kodak and Cobas-Bio were highly correlated (r = 0.99); again, the Cobas-Bio results exceeded those by Kodak in some hemodialysis patients, but always for samples with higher Fe concentrations by the Cobas-Bio. By AAS, the TIBC values of these patients also exceeded those by Kodak, to about the same extent as observed for serum Fe. These intermethod differences in Fe and TIBC were seen only in patients who had received an intravenous Fe-dextran (Imferon) injection two to three days before blood sampling but could be generated in vitro by adding Imferon to serum from normal controls. Less than 6% of dextran-bound Fe is measured as Fe by Kodak, as opposed to 20-30% by Cobas-Bio and 89-120% by AAS. We conclude that the Kodak Fe slides are superior to liquid reagents, by exclusively measuring protein-bound circulating Fe pools.

Acceptability of rilmenidine and long-term surveillance of plasma concentrations in hypertensive patients with renal insufficiency

Acceptability and plasma concentrations of rilmenidine, a new antihypertensive agent mainly eliminated via the kidney, were evaluated in 17 hypertensive patients (supine diastolic blood pressure, 104 +/- 3 mmHg) with renal insufficiency (creatinine clearance, 35 +/- 4 ml.minute-1/1.73 m2; range, 12 to 58). Patients were treated for six months with rilmenidine at the dose of 1 mg in the morning or 1 mg twice daily as single-drug therapy in untreated patients, or in combination or as substitution in patients already treated. Plasma concentrations of rilmenidine were measured by gas chromatography combined with mass spectrometry at Days 0, 1, 5, 7, 9, and 11, and Months 1.5, 3, 4.5, and 6 before administration. Supine and erect blood pressure (sphygmomanometer) measurements and side effects were noted at the same times. Laboratory and electrocardiographic parameters were evaluated at Days 0 and 11, and Months 1.5 and 6. Blood pressure was effectively controlled during the trial in 12 patients (mean decrease in systolic/diastolic blood pressure of 12/8 mmHg). Five patients were removed from the trial after Month 1.5 because of a rise in blood pressure (three cases) or noncompliance (two cases). Side effects were moderate and transient (dry mouth, constipation, daytime drowsiness, mood disturbances, insomnia) never requiring treatment withdrawal. Surveillance of renal function revealed no significant mean variation. Rilmenidine plasma concentrations reached steady state the fifth day at the latest and were related to the degree of renal insufficiency. When renal function was stable (13 cases), plasma concentrations did not vary until the end of the trial. When renal function was progressive (four cases), plasma concentrations increased in parallel in two patients, without the onset of side effects, and remained stable in the other two patients. In conclusion, this study confirmed the good acceptability of rilmenidine in hypertensive patients with chronic renal insufficiency. It showed stable plasma concentrations of rilmenidine during a six-month treatment in hypertensive patients with renal insufficiency, reflecting the absence of accumulation of the drug.

Monitoring of bone mineral content in patients on regular hemodialysis

Bone mineral content (BMC) was measured at the lumbar spine region by means of dual photon absorptiometry over a 3-year period in 20 patients on regular hemodialysis (RHD). Baseline mean BMC at the start of the monitoring was significantly decreased to 82.64% of predicted value (p less than 0.05). During a 3-year follow-up mean BMC rose significantly to 90.61% (p less than 0.05). Six patients received vitamin D supplements. Analysis of the data showed that rise of BMC was similar whether vitamin D was given or not. Our data suggest that (1) RHD inhibits bone loss at the lumbar spine level that occurred mainly before active uremia treatment and (2) the increment of BMC observed in this study can be attributed to the different site of measurement, the inaccuracy of the measurements by interference with soft tissue calcifications and the dialysis conditions.

Meprobamate poisoning, hypotension and the Swan-Ganz catheter

A case is described in which voluntary ingestion of 72 g meprobamate (mpb) was complicated by shock ascribed to cardiac failure and vasodilation, documented by hemodynamic monitoring. Forced diuresis and cardiac inotropic support were added to the therapy. We recommend Swan-Ganz monitoring in any case of mpb overdosage associated with hypotension and suggest that forced diuresis is not contraindicated if appropriate assessment of the patient's hemodynamic condition is performed.

The basic proteins of bovine allantoic fluid

This paper reports the separation of highly cationic proteins (i.e. pI greater than 9.0) of bovine allantoic fluid and their possible pathogenic properties. Experimentally, polycations and cationic proteins of pI greater than 10 induced intravascular coagulation and hemolysis, as well as precipitation of fibrinogen and proteinuria. Bovine allantoic fluid collected at the time of calving contains from 0.6 to 1.3 g of proteins per liter (11 samples). Ion-exchange chromatography, followed by either chromatofocusing or heparin-sepharose-6 beta binding, and, finally, gel filtration separated several fractions and subfractions. These were examined later using polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate, and at least ten constituents were visualized. Two components, Mr 34,000, pI 9.7, and Mr 38,000, pI 9.6-9.0, accounted for 33% of the basic proteins present in allantoic fluid and 0.7% of its total protein content. Electrophoretic mobility was unaltered by beta-mercaptoethanol, and periodic acid-Schiff staining was negative. These proteins were not found in ox plasma. The major basic proteins were bound to red cells and platelets. Cell electrophoretic mobility decreased linearly with the logarithm of protein concentration. At concentrations between 10(-6) and 10(-5) M, red cell clumping was rare; hemolysis and platelet agglutination were not observed.

Reversible membranous glomerulonephritis associated with ketoprofen

An 87-year-old woman presented with the nephrotic syndrome 12 months after administration of ketoprofen, 100 mg daily for osteoarthritis. Clinical course and laboratory data were consistent with drug-induced nephropathy. Kidney biopsy showed membranous glomerulonephritis. Evolution was favorable with resolution of proteinuria after drug withdrawal and steroid administration. A review of the literature on nephrotic syndrome associated with NSAID reveals membranous glomerulonephritis to be an unusual complication.

Intra-individual comparison of captopril and enalapril in patients undergoing regular haemodialysis

The acute and long-term efficacy, tolerance and safety of two orally active angiotensin converting enzyme (ACE) inhibitors, captopril (C) and enalapril (E) were compared in patients on regular haemodialysis (RHD). C and E were successively administered for 6 months to 8 RHD patients with hypertension unresponsive to fluid withdrawal and conventional antihypertensive therapy. The fall in blood pressure after a starting dose of 25 mg C or 5 mg E was of the same magnitude. It was not correlated with the initial PRA levels, which were normal in all patients. The mean daily dose of ACE inhibitor was 45 +/- 28 mg during the C period and 19.4 +/- 17.6 mg at the end of the E period. Three patients required additional treatment, comprising beta-blockers and/or calcium antagonists. The individual daily dose of ACE inhibitor, the need for additional treatment and the antihypertensive response achieved were highly correlated during both study periods. During C administration 4 out of 8 patients presented a taste disturbance, which disappeared 2 weeks after substituting E for C. Serum electrolytes, liver enzymes, haemoglobin concentration and white cell and platelet counts remained unchanged throughout both study periods. It is concluded that RHD patients with hypertension are responsive to ACE inhibitors, C and E being equally effective.

Diabetic microangiopathic hemolytic anemia: beneficial effect of an antiplatelet agent?

A 66-yr-old man with non-insulin-dependent diabetes mellitus complicated by retinopathy and nephropathy presented with shortened red cell survival associated with prominent fragmentation of erythrocytes and leading to severe hemolytic anemia. Neither abnormal carbohydrate tolerance per se nor renal failure was related to the red cell fragmentation syndrome. Also, a marked platelet hyperaggregability, which disappeared under treatment with ticlopidine, was demonstrated. Furthermore, during treatment with this potent platelet inhibitor, red cell survival normalized and all signs of hemolysis, as well as the schistocytes present in the peripheral blood smears, disappeared. Two weeks after stopping ticlopidine administration, microangiopathic hemolytic anemia relapsed. We suggest that the fragmentation hemolysis in this patient was related to diabetic microangiopathy, and that the beneficial effects of ticlopidine are related to its platelet-inhibiting activities. This case further reaffirms that antiplatelet agents may have a beneficial effect on the vascular disease of diabetes mellitus.

Pathogenicity of cationized albumin in the dog: renal and extrarenal effects

The effects of 21 cationized serum albumin samples of various degrees of cationization on renal function were studied in the dog. The samples were perfused intra- aortically to obtain preferential perfusion of the left kidney in 25 dogs. Standard clearance techniques were used, associated in six dogs with sieving studies of 125I-labelled polyvinylpyrrolidone (125I-PVP) and with an extensive morphological study in 15 dogs. Renal effects were observed. (a) Renal effects in left kidneys. The perfusion with weakly cationized albumin (group 1) produced moderate proteinuria associated with the deposition of cationized albumin on the anionic sites of the basement membrane. Glomerular filtration rate (GFR) was unaltered. Perfusion with highly cationized samples (group 2) produced more severe proteinuria and a significant decrease in GFR. Glomerular permeability to 125I-PVP increased. Perfusion with the four samples of highest pI (group 3) was followed by anuria. (b) Renal effects in right kidneys. A retarded mild proteinuria appeared only in group 2 and group 3 animals without alteration of GFR. All the kidneys (group 1 included), with the exception of two (group 3), showed deposition of the protein in the anionic sites. The following extrarenal effects were observed essentially in group 2 and group 3 animals: erythrocyte agglutination and haemolysis, platelet aggregation and thrombocytopenia, and a decrease in plasma fibrogen level due to fibrinogen precipitation. These effects produced progressive obstruction in the glomerular capillaries, thus explaining the occurrence of anuria. The structural damage in group 2 and group 3 left kidneys bears remarkable resemblance to that observed in the fulminant form of the human so-called 'haemolytic-uraemic syndrome'. The neutralization alone of the fixed negative charges in the glomerular wall appears to produce only mild proteinuria, whereas the various extrarenal effects combine to produce more severe proteinuria associated with functional alteration and vascular obstruction.

Group JK corynebacterium peritonitis in a patient undergoing continuous ambulatory peritoneal dialysis

We describe a case of peritonitis with isolation of a group JK corynebacterium from the peritoneal effluent in a patient undergoing continuous ambulatory peritoneal dialysis and treated with corticosteroids. Therapy with intraperitoneal vancomycin resulted in a rapid eradication of the organism. However, only 1 month after discontinuation of the 26-day therapy, a second episode of peritonitis with JK corynebacterium occurred. After vancomycin was restarted, the organism disappeared again from the peritoneal fluid, but the patient died a few days later from heart failure apparently unrelated to the infection. Some authors have mentioned the isolation of diphtheroids (without further identification) from peritoneal effluent of continuous ambulatory peritoneal dialysis patients, but to our knowledge, this is the first report of peritonitis associated with JK corynebacterium, an opportunistic organism that must be differentiated from other corynebacteria.

Effect of 1,25-dihydroxyvitamin D3 on plasma prolactin in patients with renal failure on regular dialysis treatment

Basal plasma prolactin (PRL) has been measured in 6 patients with chronic renal failure 3 months before and at monthly intervals during a 3 months 1,25-dihydroxyvitamin D3 [1,25 (OH)2-D] treatment. Plasma PRL decreased rapidly during, 1,25 (OH)2-D treatment, while it remained unchanged during the 3-months control period. There was no correlation between PRL and parathyroid hormone (PTH; measured either with carboxy- or amino-terminal assays) and several other parameters. A direct effect of 1,25 (OH)2-D on PRL secretion may exist.