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J Broekroelofs

Publications and source records attributed to J Broekroelofs.

10 recordsLinked to original sources
PubMed2004

Valproic acid intoxication: sense and non-sense of haemodialysis.

INTRODUCTION: Valproic acid is increasingly used in the treatment of epilepsy, and also prescribed for bipolar affective disorders, schizoaffective disorders, schizophrenia and migraine prophylaxis. We describe two case reports involving valproic acid intoxication with ingestion of ethanol. METHODS: One patient was treated by supportive care, one patient received haemodialysis. RESULTS: From analysis of plasma concentrations before and during haemodialysis (pre- and post-filter) it is shown that valproic acid can be effectively eliminated by haemodialysis when plasma levels are way above 100 microg/ml. In the literature, plasma protein binding is reported to be around 90% for levels within the therapeutic range. In our patient plasma protein binding was around 50% after treatment with haemodialysis. CONCLUSION: These findings make haemodialysis in valproic acid intoxication a sensible therapeutic option with increasing efficiency when plasma concentration is high. Furthermore our findings suggest that lowering valproic acid concentrations to a therapeutic level by haemodialysis does not necessarily result in an immediate, simultaneous increase in plasma protein binding of valproic acid.

Adult↗
PubMed2000

Long-term renal outcome after lung transplantation is predicted by the 1-month postoperative renal function loss.

BACKGROUND: Progressive renal function loss is common after lung transplantation. To facilitate the design of renoprotective strategies, identification of early predictors for long-term renal function loss would be useful. METHODS: We prospectively analyzed renal function [glomerular filtration rate (GFR); 125I-iothalamate clearance] in a closely monitored cohort (minimum 24-month follow-up) of 57 patients who received lung transplants between November 1990 and September 1996 in our center. The analyzed end points were the slope of the GFR from 6 months posttransplant onward and the GFR at 24 months after transplantation. RESULTS: Before transplantation, the GFR was 100 ml/min (median, range 59-163). It decreased to 67 ml/min (29-123) at 6 months, 53 ml/min (17-116) at 24 months, and 51 ml/min (20-87) at 36 months after transplantation. The magnitude of the loss of GFR 1 month post-transplantation was the only factor significantly correlated with absolute GFR at 24 months after transplantation. Pulmonary diagnosis was significantly associated with long-term rate of renal function loss. Median loss of GFR was greatest in patients with cystic fibrosis (-10 ml/min/year, range -14 to -6 ml/min/year), preserved in pulmonary hypertension (-1 ml/min/year, range -6 to +7 ml/min/year), and in between in emphysema (-6 ml/min/year, range -27 to +12 ml/min/year). No other factors could be identified. CONCLUSIONS: In lung transplant recipients, the 1-month postoperative loss of GFR is an early marker for long-term renal prognosis. Pulmonary diagnosis appears to be a relevant predictor as well. These factors may guide further research and the development of preventive strategies.

Adult↗
PubMed2000

Creatinine-based estimation of rate of long term renal function loss in lung transplant recipients. Which method is preferable?

BACKGROUND: Progressive renal function loss during long-term follow up is common after lung transplantation and close monitoring is warranted. Since changes in creatinine generation and excretion may occur after lung transplantation, the reliability of creatinine-based methods of renal function assessment to serial measurements of glomerular filtration rate (GFR) were compared in this population. METHODS: Renal function with serial measurements of GFR by iothalamate clearance every 6 months after transplantation was studied in a cohort of 40 lung transplant recipients with at least 24 months of follow up, transplanted between November 1990 and October 1995 in this center. The correlation between the rate of renal function loss calculated from the slope of GFR and the following creatinine-based indices: 1/S-creatinine, Cockcroft clearance and Levey estimation were analyzed. The absolute difference between GFR and Cockcroft clearance and Levey estimation pre- post-transplantation at several points was also studied. RESULTS: The slopes of 1/S-creatinine (r = 0.85), Cockcroft clearance (r = 0.86), and the Levey estimation (r = 0.84) correlated significantly with the slope of GFR as measured by iothalamate clearance. However, all creatinine-based slopes underestimate the rate of GFR loss. Cockcroft clearance and the reciprocal value of serum creatinine do not detect small GFR losses. During long-term follow up a time-dependent discrepancy between Cockcroft clearance, Levey estimation and GFR was observed which may partially explain the observations for this population. CONCLUSION: Creatinine-based slopes correlate with GFR slopes after lung transplantation, but consistently underestimate the rate of GFR decline. The Levey estimation is the most sensitive method used to detect small GFR losses and may be preferable when no GFR measurement is available. In special conditions when an accurate renal function assessment is needed true GFR may be necessary.

Adult↗
PubMed1998

Risk factors for long-term renal survival after renal transplantation: a role for angiotensin-converting enzyme (insertion/deletion) polymorphism?

Chronic progressive renal function loss is a main cause of long-term graft loss after initially successful renal transplantation. Transplanted kidneys share some risk factors for renal function loss, such as hypertension or proteinuria, with diseased native kidneys. Recently, it has been shown that renal function loss is influenced by the angiotensin-converting enzyme (ACE) (insertion/deletion [I/D]) genotype in renal disease in diseased native kidneys. This study examines whether donor or recipient ACE (I/D) genotype is a risk factor for graft loss after renal transplantation. To avoid bias by acute events, graft survival was studied, with patients dying with a functioning graft censored, starting at 12 mo after transplantation in a cohort of 367 patients transplanted between 1987 and 1994 with at least 2 yr of follow-up. Mean follow-up was 58 mo. ACE (I/D) genotype was determined by PCR on stored donor and recipient lymphocytes. Neither donor nor recipient ACE (I/D) genotype was associated with graft survival. However, Cox proportional hazards analysis identified recipient, but not donor, ACE (I/D) genotype D-allele to be independently associated with a shorter time to graft loss in subgroups of patients at high risk for graft loss defined by a creatinine clearance <50 ml/min (n = 108, P = 0.017) or proteinuria > or =0.5 g/24 h at 12 mo (n = 97, P = 0.0051) after transplantation. In conclusion, recipient ACE (I/D) genotype was associated with time to graft loss in a specific high-risk subgroup of the study population. This suggests that the effect of ACE (I/D) genotype on graft survival only becomes apparent when other risk factors are simultaneously present.

Adult↗
PubMed1996

Renal hemodynamics after lung transplantation. A prospective study.

Renal function impairment is common after solid organ transplantation, due to the nephrotoxicity of cyclosporine. Moreover, in patients with severe respiratory failure, renal function is often impaired. This renal function impairment may predispose patients to further renal function impairment after lung transplantation. Therefore, renal hemodynamics were measured in 44 patients before lung transplantation and 1, 6, 12, 18, 24, and 30 months after transplantation. After transplantation, a decline in renal function occurred, with a progressive fall in glomerular filtration rate (GFR) of 33 +/- 4% at 12 months and 42 +/- 9% at 30 months. Effective renal blood flow fell by 22 +/- 5% at 12 months and remained stable thereafter. Changes in effective renal plasma flow (ERPF) were less pronounced than those of effective renal blood flow, due to a fall in hematocrit after transplantation. Blood pressure and renal vascular resistance increased significantly, consistent with the effects of cyclosporine. Prior to transplantation, renal function impairment with intense renal vasoconstriction had been found in a subset of the patients. Remarkably, the decrease in renal function after transplantation was less pronounced in patients with renal function impairment prior to transplantation, as indicated by significant negative correlations between pretransplantation GFR and the percentage change in GFR after transplantation, and pretransplantation ERPF and the percentage change in ERPF after transplantation. This suggests that the net course of renal hemodynamics after lung transplantation is the result of the opposed effects of cyclosporine nephrotoxicity and the favorable effects of the normalization of respiratory status. In conclusion, after lung transplantation a decline in renal function occurs that is less pronounced in patients with renal function impairment and intense renal vasoconstriction prior to transplantation. Such a renal function impairment, therefore, should not be considered a contraindication to lung transplantation.

Adult↗
PubMed1994

Anti-neutrophil cytoplasmic antibodies (ANCA) in sera from patients with inflammatory bowel disease (IBD). Relation to disease pattern and disease activity.

Anti-neutrophil cytoplasmic antibodies producing a perinuclear fluorescence pattern on ethanol-fixed granulocytes (p-ANCA) were found in 33 of 67 patients (49%) with ulcerative colitis (UC) but also in 14 of 35 patients (40%) with Crohn's disease (CD). In the latter condition p-ANCA were equally present in subgroups with colonic, ileocolonic, or ileal involvement only. Titers of p-ANCA were higher in patients with UC compared to CD patients, in particular when comparing patients with active disease. In contrast to findings in CD, patients with active UC had higher titers of p-ANCA than patients with inactive UC. Although p-ANCA were incidentally directed to lactoferrin, both in UC and CD, and to proteinase-3 and myeloperoxidase in UC only, the antigenic nature of p-ANCA could not be identified in most of the cases. We conclude that, within the spectrum of inflammatory bowel disease, the presence of p-ANCA is not specific for UC. When titers of p-ANCA are taken into account, the presence of high-titered p-ANCA, however, suggests active UC.

Adolescent↗
PubMed1994

Anti-neutrophil cytoplasmic antibodies (ANCA) in inflammatory bowel disease: characterization and clinical correlates.

ANCA were detected by indirect immunofluorescence in 34 out of 67 patients with ulcerative colitis (UC, 51%) and in 14 out of 35 patients with Crohn's disease (CD, 40%). All but one ANCA-positive sera produced a perinuclear pattern of fluorescence (P-ANCA) on ethanol-fixed neutrophils. On paraformaldehyde-fixed neutrophils 76% of P-ANCA-positive sera in UC and 50% of P-ANCA-positive sera in CD produced cytoplasmic fluorescence, indicating that, indeed, cytoplasmic antigens are recognized by a considerable number of these sera. By Western blot analysis using whole neutrophil extract as a substrate 46% of sera from patients with UC and 32% of sera from patients with CD showed reactivity with either lactoferrin, polypeptides occurring as a doublet of 66/67 kD mol. wt, or polypeptides occurring as a doublet of 63/54 kD mol. wt, respectively. Identical patterns of reactivity have been observed among P-ANCA-positive sera from patients with autoimmune liver disease and rheumatoid arthritis. These data suggest that ANCA of restricted specificities are not specific for inflammatory bowel disease (IBD), but are present in diverse conditions characterized by chronic idiopathic inflammation.

Adolescent↗
PubMed1993

Antineutrophil antibodies in inflammatory bowel disease recognize different antigens.

Anti-neutrophil cytoplasmic antibodies (ANCA) were observed in 31 out of 68 sera (45%) from Ulcerative Colitis (UC) patients and in 13 out of 38 Crohn's Disease (CD) sera (34%). The presence of ANCA was not related to disease activity, nor to the localization of the disease manifestations. By Western Blotting ANCA showed reactivity with either lactoferrin, polypeptides occurring as a doublet of 66/67 kD MW, or polypeptides occurring as a doublet of 63/54 kD MW.

Antibodies, Antineutrophil Cytoplasmic↗