Outcome of desensitization in human leukocyte antigen- and ABO-incompatible living donor kidney transplantation: a single-center experience in more than 100 patients.

BACKGROUND: Antibody-mediated rejection (AMR) and inferior graft outcome remain the 2 most important obstacles to successful kidney transplantation in human leukocyte antigen (HLA)- and ABO-incompatible recipients. We report a single-center experience in the outcome of desensitized living donor HLA- and ABO-incompatible kidney transplantation. METHODS: Since 2007 we included 2 groups in our desensitization program. HLA-incompatible living donor kidney transplant candidates displaying donor-specific antibodies (DSA) with or without a positive T-cell and/or B-cell flow crossmatch (FCXM). Second, those displaying DSA with positive T-cell immunoglobulin (Ig)G AHG CDC CXM with a titer of ≤1:8, as well as all ABO-incompatible living donor kidney transplant candidates with an IgM isoagglutinin titer ≤ 256. They were risk stratified for AMR and underwent individualized desensitization protocol: ABO-incompatible and HLA-incompatible candidates with either positive AHG CDC CXM or positive T and/or B IgG flow CXM with repeat HLA mismatch from a previous transplantation were deemed to be high risk and received a single dose of Rituximab, therapeutic plasma exchange and high-dose intravenous immunoglobulin (IVIG) (2 g/kg). HLA-incompatible candidates with negative CDC but positive T and/or B IgG FCXM were deemed intermediate risk, receiving rituximab and high-dose IVIG. Those with positive DSA but negative flow and CDC CXM were deemed low risk, receiving low-dose IVIG (1 g/kg). All patients received induction with thymoglobulin and were maintained on a tacrolimus-based immunosuppressive regimen. RESULTS: Among 124 incompatible recipients, 85 received HLA-incompatible and 39 ABO-incompatible living donor kidney transplantations after desensitization. Risk stratification for HLA-incompatible transplants revealed 61 high-risk, 42 intermediate-risk, and 21 low-risk cases. Ninety-nine (80%) were primary transplants. At a median follow-up of 23 (range 1-53) months, patient survival was 98% and death censored graft survival 96%. Mean serum creatinine was 84 µmol/L (range 41-169). Acute cellular rejection was observed in 15 (12%) and AMR in 5 (4%) patients. All rejection episodes responded to treatment except 1 AMR in an ABO-incompatible transplant that led to graft failure. CONCLUSION: Our risk stratification for desensitization strategy achieved a low incidence of AMR among HLA- and ABO-incompatible kidney transplant recipients. Their 2-year data appear to be comparable to HLA- and ABO-compatible transplantations.

Targeted monitoring of donor-specific HLA antibodies following renal transplantation.

Development of de novo donor-specific anti-HLA antibody (DSA) with antibody-mediated rejection (AMR) is the most important cause of renal allograft loss. Therefore, DSA monitoring might identify grafts susceptible to chronic humoral injury. However, implementing universal monitoring is logistically difficult, costly, and not yet supported by management guidelines, especially in patients with stable graft function. To gain further insight into humoral alloimmunity in transplant patients, we conducted a single center, retrospective study of AMR due to de novo DSA. We excluded patients without full characterization of the HLA specificities by single antigen solid phase immunoassay, and those where the clinical relevance of the DSA could not be determined. The clinical scenarios preceding AMR, HLA mismatches and alloantibody specificities, the histopathological phenotypes, and graft outcome were studied. We identified 44 renal transplant recipients with indication and protocol biopsies (44 biopsies for cause and 2 protocol biopsies), revealing 46 episodes of AMR and DSA (2 episodes in two patients). Most were late (more than 6 months after transplant). Suboptimal immunosuppression was an important prelude, usually due to non-adherence. DSA to DQ was prevalent and most biopsies were C4d positive. In all, 20 graft losses were attributed to AMR. From this study, we propose DSA monitoring in the patients with the following: (1) an episode of late (> 6 months) rejection; (2) history of non-adherence to immunosuppression; (3) immunosuppression minimization; (4) a class II loci (DR and DQ) mismatch transplant; or, (5) history of previous transplants. Close surveillance and protocol biopsies in those who develop de novo DSA is suggested.

Bortezomib as an adjuvant to conventional therapy in the treatment of antibody mediated rejection (AMR): the full spectrum.

Antibody-mediated rejection (AMR) is a well-known complication of kidney transplantation. Its incidence is higher in HLA and ABO incompatible transplant recipients and in patients who develop de novo HLA antibodies. Different clinical and histological phenotypes of HLA-related AMR have been described with variable responses to conventional AMR treatment (Plasmapheresis, IVIG, thymoglobulin (ATG), and anti-CD20 antibodies). Regardless of the phenotype, once the HLA primed B cells have differentiated into antibody producing long-lived plasma cells, they become less vulnerable to conventional AMR treatment. Bortezomib (Velcade) is a proteasome inhibitor approved by the FDA for the treatment of multiple myeloma. It targets mature plasma cells, and hence it is intriguing to study its role in the suppression of long-lived plasma cells. Several previous reports have suggested effectiveness of Bortezomib in the treatment of AMR. We report our experience with Bortezomib as an adjuvant to conventional therapy in five distinct phenotypes of AMR: early acute AMR in the context of desensitization; subclinical acute AMR in the context of desensitization; late acute AMR due to de novo HLA antibody; late ACR and acute AMR due to de novo HLA antibody and chronic AMR due to de novo HLA antibody.

Oxidative stress in renal dysfunction: mechanisms, clinical sequelae and therapeutic options.

Oxidative stress has been increasingly linked to the high incidence of cardiovascular events in patients with chronic kidney disease (CKD), especially as traditional cardiovascular risk factors seem to not be able to account for the huge cardiovascular morbidity and mortality in this population group. Oxidative stress is increased in patients with renal impairment as a result of increased oxidant activity and reduced antioxidant capacity, and this is increased in a graded manner with increasing renal dysfunction. Inflammation, which is also present in CKD, further amplifies the oxidant generation process. The two clinical sequelae of oxidative stress are endothelial dysfunction and left ventricular hypertrophy, which have adverse cardiovascular consequences. With our new understanding of oxidative stress, it is now important to assess treatment options that reduce it in the hope that they reverse endothelial dysfunction and left ventricular hypertrophy and the clinical sequelae of these abnormalities.

Congenital melanocytic nevus studded with strawberry haemangioma on the scalp.

A six-month-old male infant presented with congenital melanocytic nevus (CMN) studded with strawberry haemangioma on the right side of scalp since birth. Both lesions were gradually increasing up to the present size. The case is being reported for its rare occurrence.

Pityriasis rosea unilateralis.

The classical pityriasis rosea presents with erythematous papulosquamous lesions. It has got many clinical and morphological variants. Pityriasis rosea unilateralis is very rare variant of pityriasis rosea. We are reporting two cases of unilateral pityriasis rosea.

Topical 20% KOH--an effective therapeutic modality for moluscum contagiosum in children.

Topically 20% KOH aqueous solution once daily at bedtime was applied in 27 children having molluscum contagiosum by their parents, till lesions showed signs of inflammation or superficial ulceration. 24 children (88.9%) completed the trial and complete clearance was achieved after a mean period of 17 days. No recurrence was observed during follow up period. Thus in this open trial topical 20% KOH aqueous solution has proved to be convenient, easy to apply at home, safe and inexpensive alternative therapeutic modality for the treatment of molluscum contagiosum in children.

Pachyonychia congenita-like nail changes treated successfully with a combination of vitamins A and E: a case report.

A 20-year-old man presented with thickening, subungual hyperkeratosis and discoloration of all the nails of both hands and both great toes since birth. No other ectodermal abnormalities were found. Treatment with vitamins A and E in high doses along with a moisturizing ointment topically for one year resulted in complete resolution of all nail abnormalities.

Antineutrophil cytoplasm antibody-induced neutrophil nitric oxide production is nitric oxide synthase independent.

BACKGROUND: Antineutrophil cytoplasm antibodies (ANCAs) are implicated in the pathogenesis of systemic vasculitis. We asked whether ANCA could induce nitric oxide (NO) release from human neutrophils and, if so, whether this NO production was dependent on NO synthase (NOS) activity. METHODS: Neutrophil NO production was measured using a chemiluminescence assay, and NOS activity was determined by the conversion of [(14)C] L-arginine to [(14)C] L-citrulline and NOS mRNA expression by reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: Human neutrophils isolated from healthy donors were incubated at 37 degrees C with human ANCA, normal human IgG, murine monoclonal myeloperoxidase ANCA, murine proteinase-3 ANCA, or their respective isotypic controls for 6 to 12 hours in RPMI. Both human and monoclonal ANCA led to a dose-dependent increase of NO compared with control IgG. Neutrophils, either freshly isolated or incubated for seven hours with murine monoclonal myeloperoxidase ANCA, proteinase-3 ANCA, or a mixture of interleukin-1 beta, tumor necrosis factor-alpha, interferon-gamma plus lipopolysaccharide showed no NOS activity with low conversion rates of [(14)C] L-arginine to [(14)C] L-citrulline, which could not be inhibited by N(G)-monomethyl-L-arginine (NOS inhibitor). To detect NOS mRNA expression, RT-PCR was performed using oligonucleotide primers derived from mRNA sequences of either human constitutive endothelial NOS (eNOS), constitutive neuroneal NOS (nNOS), or human hepatocyte inducible NOS (iNOS). There was no expression of either eNOS, nNOS, or iNOS in untreated, human and murine monoclonal ANCA-treated, or cytokine-treated neutrophils. CONCLUSION: These data suggest that human neutrophils produce NO in response to ANCA but in a NOS-independent way. NO can be generated from a nonenzymatic interaction between hydrogen peroxide and arginine. We postulate that this is the predominant pathway of NO synthesis in neutrophils, since ANCAs are capable of inducing reactive oxygen species production from neutrophils.

Rhabdomyolysis and acute renal failure complicating detergent ingestion.

Rhabdomyolysis should be considered in the aetiology of all patients with unexplained acute renal failure (ARF). Early recognition provides the opportunity to initiate therapy aimed at preventing or limiting nephrotoxicity from the released heme pigment, myoglobin. We report an adult patient who developed ARF following the ingestion of a large amount of household detergent which, as far as we are aware, has not been previously described. The report illustrates the importance of measuring muscle enzyme levels and urinary myoglobin to confirm the possibility of rhabdomyolysis in any unusual presentation of ARF.

The changing pattern of glomerulonephritis in Singapore over the past two decades.

This study reviews the pattern of glomerulonephritis (GN) in Singapore over the past 2 decades. In the earlier decade the pattern was typical of most Asian countries with mesangial proliferative GN (Mes GN) (56%) as the most common form of primary GN including the nephrotic syndrome (40%). In the 2nd decade the pattern undergoes a change. Though Mes GN is the commonest primary GN (42%), the commonest form of nephrotic syndrome is now minimal change disease (30%) with Mes GN decreasing to 25% among all primary nephrotic syndromes. Both minimal change and focal global sclerosis account for 50% of steroid/cyclophosphamide responsive GN today. Membranous GN though still uncommon, has increased from 3% (1st decade) to 6% (2nd decade) (p < 0.01). IgA nephritis is still the commonest primary GN occurring in Singapore (42% of all primary GN in the 1st decade and 45% in the 2nd decade). The present pattern of GN in Singapore, though, still predominantly Asian with the preponderance of mesangial proliferative GN with a relatively low incidence of membranous GN contrasts with the pattern in the West where membranous GN is the commonest form of primary GN. Even the incidence of FSGS has not increased as in the West where there is a rising incidence. The underlying basis for most GN in Singapore as in other Asian countries and elsewhere is antigen-driven: infective antigen as well as food or other allergens.

Food interaction pharmacokinetic study of cordaflex 20 mg retard filmtablet in healthy volunteers.

The aim of the present study was to investigate the effect of food consumption on the pharmacokinetics of Cordaflex 20 mg retard filmtablet in healthy volunteers through measuring nifedipine plasma levels by an HPLC-ED method both after fasting and food ingestion. The food interaction pharmacokinetic study of Cordaflex 20 mg retard filmtablet was carried out in 12 healthy male volunteers treated with a single dose of the preparation both after fasting and after food ingestion, in a crossover design allowing 1 week of wash-out period between the 2 treatments. Nifedipine concentration of plasma samples were determined by an isocratic HPLC-ED method [Horvai et al. 1994] with robotic sample processing [Horváth et al. 1995, 1996]. The pharmacokinetic parameters (AUC0-infinity, AUC0-t, Cmax, MRT) were analyzed by calculating 90% confidence interval for logarithmic transformed test/reference ratio values, and Schuirmann's statistical tests, the tmax and HVD values were analyzed by Wilcoxon's nonparametric statistical test. The above statistical tests of the present food interaction study indicated significant differences for each one of the respective pharmacokinetic parameter pairs calculated for treatments after fasting and after food ingestion. On the basis of the above findings and also by comparing the mean pharmacokinetic curves, it was evident, that, in agreement with the data of literature [Kleinbloesem et al. 1993, Schall et al. 1994], food ingestion increased the relative bioavailability and maximum plasma concentration (Cmax). Considering the average of the parameter values and also the respective statistical tests, it was also apparent that the time to maximum plasma concentration (tmax), the mean residence time (MRT), and the half-value duration (HVD) all decreased significantly upon the effect of food ingestion.

Controlled trial of pulse versus continuous prednisolone and cyclophosphamide in the treatment of systemic vasculitis.

Although cyclophosphamide and prednisolone are effective in treating systemic vasculitis, the optimum treatment regimes and duration of treatment are unknown. We randomized 54 patients aged 15-70 years (median 57.5 years) with systemic vasculitis (classical polyarteritis n = 8, microscopic polyarteritis n = 17, Wegener's granulomatosis n = 29) to treatment with either pulse cyclophosphamide and prednisolone (PCYP) (n = 24) or continuous oral and prednisolone and cyclophosphamide, with the latter followed after a median of 3 months (range 1.5-10 months) by azathioprine (CCAZP) (n = 30). Patients on CCAZP were more likely to develop leucopenia (13/30) than patients on PCYP, (7/24) although the difference was not significant. The numbers of infective episodes during follow up were comparable in the two groups at 1.7/patient for PCYP and 1.66/patient for CCAZP. Overall, 26/30 patients (87%) treated with CCAZP developed treatment-related toxicity, as did 17/24 patients (71%) treated with PCYP. After a median follow-up of 40.4 months (range 0.7-64.8), there was no difference in the frequency of deaths (PCYP 5, CCAZP 4), relapses (PCCYP 7, CCAZP 8), treatment failures (PCYP 4, CCAZP 4), improvement in disease activity scores or renal function. Survival at three years was 77% in patients treated with PCYP, and 90% in patients on CCAZP (p = 0.38). There was a tendency towards increased toxicity in patients treated with the continuous regimen.

Human bioequivalence study of a new nifedipine containing retard filmtablet after single and repeated administration.

A clinical pharmacokinetic bioequivalence study with two retard filmtablet preparations, both containing 20 mg of nifedipine (CAS 219829-25-4) was carried out. The investigated test preparation was Cordaflex 20 mg retard filmtablet. The pharmacokinetic parameters were determined after single and repeated administration in 15 and 16 healthy male volunteers, respectively, in open, randomised studies of cross-over design. Plasma levels of nifedipine were determined by HPLC with electrochemical detection using a robotic sample preparation technique. Statistical comparison of the pharmacokinetic parameters (AUC0-infinity, AUCss, tau tmax, Cmax, Css,min, Css,av, MRT, etc.) calculated from plasma concentration-time curves by ANOVAlog, confidence interval, Schuirman's, Westlake's, Anderson's and Wilcoxon's tests, furthermore the comparison of the clinical results did not show any significant difference between the two preparations. It is concluded that the two preparations are bioequivalent after repeated administration.

Sensitive high-performance liquid chromatographic determination of nifedipine in dog plasma using an automated sample preparation system with laboratory robot.

Nifedipine, a calcium-channel blocking drug was analysed in dog plasma after oral dosing with two different formulations. Sample preparation was automated with a laboratory robot. Quantitative determination of the drug was performed on a reversed-phase HPLC system with electrochemical detection (ED) using an internal standard. Validation of the analytical method showed that the system is well suited for pharmacokinetic studies on dogs. The assay was linear in the range 1-50 ng/ml. Inter-day and intra-day variability were between 6.43-18.15% C.V. and 1.57-5.53% C.V., respectively.

Glomerular vascular cell adhesion molecule-1 expression in renal vasculitis.

AIMS: To study the expression of cell adhesion molecules in the renal biopsy specimens of patients with systemic vasculitis and Henoch-Schönlein purpura (HSP); to correlate this with the severity of glomerular inflammation. METHODS: Renal biopsy specimens obtained from eight patients with untreated systemic vasculitis (four with Wegener's granulomatosis and four with microscopic polyarteritis), eight with HSP and nine controls (four with normal histopathology and five with thin glomerular basement membrane disease) were stained using the alkaline phosphatase anti-alkaline phosphatase method with monoclonal antibodies directed against intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and E-selectin. RESULTS: Biopsy specimens of normal kidneys expressed ICAM-1 in glomerular endocapillary cells, Bowman's capsule epithelium, interstitial cells and interstitial vascular endothelium, and VCAM-1 in Bowman's capsule epithelium, proximal tubular epithelium and interstitial vascular endothelium. No staining with antibody directed against E-selectin was seen in any of the biopsy specimens. Biopsy specimens of patients with a vasculitic glomerulonephritis (segmental necrotising glomerulonephritis) expressed VCAM-1 in glomerular endocapillary cells (four of eight patients with systemic vasculitis; two of eight patients with HSP). In patients with a systemic vasculitis glomerular VCAM-1 expression was associated with a more severe renal lesoin (44, 50, 60, and 65% of glomeruli involved) than in those not showing glomerular VCAM-1 expression (3, 3, 11, and 39% of glomeruli involved). CONCLUSION: Expression of VCAM-1 by glomerular endocapillary cells in renal biopsy specimens raises the possibility that recruitment of VLA-4 bearing leucocytes may contribute to glomerular injury in Wegener's granulomatosis and microscopic polyarteritis.

Circulating soluble adhesion molecules in inflammatory bowel disease.

OBJECTIVE: To determine levels of soluble forms of the cell adhesion molecules (CAM), ICAM-1, E-Selectin and VCAM-1 in relation to prevalence, treatment and disease activity in inflammatory bowel disease. PATIENTS AND METHODS: Plasma was obtained from patients with ulcerative colitis (n = 49), patients with ulcerative colitis who had undergone restorative proctocolectomy (n = 32, eight of whom had a clinical pouchitis), Crohn's disease patients (n = 34) and 24 healthy controls. RESULTS: Plasma soluble ICAM-1 levels [medians (ranges in ng/ml)] were significantly higher in patients with active ulcerative colitis [270 (90-510)], pouchitis [415 (310-670)] and active Crohn's disease [305 (200-630)] than in those with inactive ulcerative colitis [225 (140-425), P = 0.031], non-inflamed ileoanal pouch [260 (140-380), P = 0.0004] and inactive Crohn's disease [245 (90-520), P = 0.045], respectively, and controls. The soluble E-Selectin levels were also significantly higher in patients with active ulcerative colitis [55 (40-140)], pouchitis [90 (45-145)], and active Crohn's disease [78 (30-115)] than in those with inactive ulcerative colitis [45 (20-80, P = 0.003], non-inflamed ileoanal pouch [45 (20-90), P = 0.001] and inactive Crohn's disease [48 (25-90, P = 0.020], respectively, and controls. CONCLUSIONS: The present study suggests that increased levels of soluble ICAM-1 and soluble E-Selectin occur during active inflammatory bowel disease and pouchitis, which may be used as sensitive markers of continuing inflammation.