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H J Ward

Publications and source records attributed to H J Ward.

31 records · Page 2Linked to original sources
PubMed1988

Declining incidence of wound infection in cadaveric renal transplant recipient.

Over a five-year period 100 cadaveric renal transplants were performed. In 91 of these recipients, a prophylactic parenteral antibiotic (cefoperazone) was administered and closed wound drainage was used. Of these 91 patients, 33 received azathioprine/prednisone immunosuppression, whereas cyclosporine/prednisone with or without azathioprine was used in the remaining 58. The incidence of wound infections was significantly reduced from 12 per cent (4/33) in the azathioprine group to 1.7 per cent (1/58) in the cyclosporine group (p less than 0.01). When conventional immunosuppression (azathioprine/prednisone) is employed in renal transplantation, triple antibiotic prophylaxis that includes an aminoglycoside is most effective in preventing wound infections. A single non-nephrotoxic antibiotic, cefoperazone, offers similar protection in the cyclosporine/prednisone-treated renal transplant recipient.

Cadaver↗
PubMed1988

Cadaveric renal transplantation: surgical results and expectations in the cyclosporine era.

During a 36-month period 100 patients received 104 cadaveric renal transplants with cyclosporine-based immunosuppression. Of the patients 26 required 31 additional operations. Of the 19 secondary operations performed 1 month after transplantation 18 were emergency in nature, whereas beyond this period the majority of the procedures were elective. Both deaths in this series were related to the operation. Only 1 graft loss was directly attributed to a secondary operation. The patient undergoing cadaveric renal transplantation is at significant risk (25 per cent) of requiring at least 1 additional operation. However, despite this high probability of reoperation, graft loss and patient death after such procedures should be rare.

Adult↗
PubMed1988

Immunopathologic features of de novo membranous nephropathy in renal allografts.

De novo membranous nephropathy (MN) is now one of the most common forms of posttransplant glomerular disease, second only to allograft glomerulopathy. We investigated several immunopathologic and physicochemical properties of the immune complex (IC) or IC components displayed in the sera of patients with de novo MN. The parameters studied included detection of small (9S) preformed IC by monoclonal rheumatoid factor, determination of IC isoelectric point by chromatofocusing, detection of cationic IgG spectrotypes (pI 8.0-9.2), and demonstration of brush border or tubular epithelial/interstitial antibodies in the sera by indirect immunofluorescence. Of 7 de novo MN sera, 5 demonstrated the presence of each of these four immunopathologic features, whereas normal transplant patients, transplant recipients with recurrent focal sclerosis (FSGN), and those with chronic rejection did not display such features. Sera of patients with untreated idiopathic MN revealed immunochemical properties of IC that were similar to those seen in circulating IC of de novo MN. These studies suggest that a strongly nephritogenic internal milieu exists in transplant recipients with de novo MN. Our data indicate that unique immunochemical properties of IC or their components may predispose to subepithelial immune deposit formation and should provide new insights into the pathogenesis of idiopathic human MN.

Adult↗
PubMed1988

Infection patterns in cyclosporine-treated cadaveric renal transplant patients.

Immunosuppression with Cs regimens has not significantly altered infection patterns relative to earlier modalities. However, reports of increased infection, especially with CMV/PCC, are not borne out in our experience both in numbers and timing of infections. Patients on low-dose Cs immunosuppression do continue to acquire infectious complications but, in general, rarely will lose their grafts or lives.

Cyclosporins↗
PubMed1987

The current role of pre-transplant blood transfusions and tissue typing in cadaveric renal transplantation.

In a retrospective analysis of 74 consecutive cadaveric renal transplants performed at our center during a 38-month period we assessed the influence of random blood transfusions and tissue matching on graft and patient survival. All patients received cyclosporine and low dose prednisone with or without azathioprine as immunosuppressive therapy. Actual patient survival was 100 per cent at 1 year and actuarial 1-year graft survival was 82 per cent. Random blood transfusions and histocompatibility matching at the HLA-DR locus did not influence graft survival. Matching at 2 or more HLA-A and B loci was associated with a significant detrimental influence (p less than 0.05) on graft survival. We conclude that the use of cyclosporine-based immunosuppression overcomes much of the adverse effect of poor tissue matching and may obviate the need for random blood transfusions in cadaveric renal transplantation during the first year of engraftment.

Azathioprine↗
PubMed1987

Recurrent Henoch-Schönlein purpura following renal transplantation.

A 20-year-old patient with Henoch-Schönlein purpura leading to end-stage renal failure received a living-related renal transplant. She was treated with conventional immunosuppressive therapy. Following a quiescent period of 18 months pretransplant, at 3 months after engraftment there was recurrence of purpuric lesions with subsequent abdominal pain and glomerulonephritis. Renal and skin biopsies confirmed the immunopathologic changes of Henoch-Schönlein purpura. This case represents the second report of an adult with multiorgan recurrence of Henoch-Schönlein purpura following transplantation.

Adolescent↗
PubMed1984

In situ formation of subepithelial immune complexes in the rabbit glomerulus: requirement of a cationic antigen.

In a previous study we examined the role of antigenic electrical charge as a factor influencing glomerular immune complex (IC) localization in the rabbit. From that study patterned after chronic serum sickness nephritis it was demonstrated that the administration of charge-modified cationic bovine serum albumin (BSA) of isoelectric point (pI) greater than or equal to 9.5 invariably resulted in heavy subepithelial deposits, whereas native BSA (anionic, pI 4.5) produced principally mesangial deposits. In order to investigate the mechanism by which the immune deposits formed, passive serum sickness was induced in New Zealand white rabbits by unilaterally perfusing kidneys of nonimmunized rabbits with five alternating cycles of saline, antigen and antibody, or immunized rabbits with saline and antigen alone. Localization of BSA and IgG along the glomerular basement membrane (GBM) occurred only after exposure to cationic BSA and antibody; nonimmunized animals perfused with cationic BSA and antibody to cationic BSA uniformly developed generalized, diffuse nearly linear deposits of IgG and BSA along the GBM. Similar deposits, which became progressively more granular after exposure to circulating antibody, were seen after the perfusion of cationic BSA alone into animals actively immunized with cationic or native BSA. Ultrastructural examination showed effacement of foot processes and isolated, irregular subepithelial and subendothelial deposits. Control perfusion employing alternating cycles of native BSA and anti-native BSA antibody, cationic BSA and normal sheep IgG, or native BSA alone in animals actively immunized with native or cationic BSA failed to develop glomerular IgG deposits. All control kidneys were normal on ultrastructural examination.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1983

Electrical charge. Its role in the pathogenesis and prevention of experimental membranous nephropathy in the rabbit.

Intravenous cationic bovine serum albumin (BSA, pI > 9.5) induces membranous nephropathy in immunized rabbits. In this study, unimmunized rabbits received intravenous injections of cationic (n = 3) or native (n = 3) or native (n = 3) BSA, followed by ex vivo isolated left renal perfusions with sheep anti-BSA antibody. Capillary wall deposits of IgG and C3 were seen exclusively in the group receiving cationic BSA, confirming an in situ pathogenesis for cationic, BSA-induced membranous nephropathy, and demonstrating the importance of a cationic antigen for its production. We then explored whether membranous nephropathy in this model is prevented by the concomitant injection of protamine sulfate, a filterable, relatively non-immunogenic polycation. An in vitro study demonstrated that protamine sulfate incubated with glomerular basement membrane (GBM) decreased the subsequent binding of radiolabeled cationic BSA (P < 0.05). In vivo, protamine sulfate was shown to bind to anionic sites in the glomerular capillary wall after intravenous injection.Groups of rabbits received 3 wk of daily intravenous injections of cationic BSA alone (n = 15) or cationic BSA and protamine (n = 18). After 2 wk of injection of cationic BSA alone, typical membranous nephropathy developed. Granular deposits of IgG and C3 were present along the GBM associated with subepithelial dense deposits, foot process effacement, and marked albuminuria. Protamine significantly reduced or prevented the formation of deposits (P < 0.001) and in6 of 18 protamine-treated animals, existing deposits decreased or disappeared between 2 and 3 wk of injection. Albuminuria was significantly reduced in protamine-treated animals with a mean of 124+/-55 mg/24 h compared to 632+/-150 mg/24 h in the control group receiving cationic BSA alone. No significant differences between the groups were noted in serum lev9lsof IgG, C3, anti-BSA antibody, or circulating immune complex size. Studies in additional animals (n = 5) given radiolabeled cationic BSA showed that protamine did not alter the clearance of cationic BSA from serum. Control experiments showed that protamine's beneficial effects were not related to its weak anticoagulant property or toits theoretical ability to deplete tissue histamine. The administration of heparin (n = 6) or diphenhydramine (n = 6) had no effect on the development of the epimembranous lesion compared to the group receiving cationic BSA alone. In addition, homogenized whole kidney histamine content was not significantly different in the group receiving cationic BSA alone compared to the group receiving cationic BSA and protamine. This work shows that a cationic BSA-induced glomerular lesion can be produced by a renal perfusion technique involving in situ complex formation and that this process requires a cationic antigen for its development. We believe that the demonstrated beneficial effects of protamine are due to its ability to bind to glomerular anionic sites, and that this electrostatic interaction results in inhibition for the further binding of the cationic antigen, thereby limiting the severity of glomerulonephritis in this model.

Animals↗
PubMed1982

Induction of membranous nephropathy in rabbits by administration of an exogenous cationic antigen.

We examined the role of antigenic electrical charge as a determinant of glomerular immune complex localization in the rabbit. Serum sickness nephritis was induced in groups of New Zealand white rabbits by daily 25-mg intravenous injections of bovine serum albumin (BSA) chemically modified to be cationic (pI > 9.5) or more anionic (pI, 3.5-4.6); an additional group received unmodified native BSA (pI, 4.5-5.1). Factors known to influence immune complex localization, e.g., molecular size of the administered antigen and resulting circulating immune complexes, immunogenicity, and disappearance time from the circulation were examined and found to be similar for both anionic and cationic BSA. Charge modification did increase the nonimmune clearance of cationic and anionic BSA compared with native BSA. Injected cationic BSA was shown in paired label experiments to bind directly to glomeruli compared with native BSA. The renal lesion produced by cationic BSA was markedly different from that found in rabbits given anionic or native BSA. Animals receiving cationic BSA uniformly developed generalized diffuse granular capillary wall deposits of IgG, C3, and BSA detected after 2 wk of injections and increasing until death at 6 wk. Qualitatively similar deposits were produced by the administration of low doses of cationic BSA of only 1 or 10 mg/d. In contrast, the injection of both anionic and native BSA resulted in mesangial deposits at 2 and 4 wk with capillary wall deposits appearing by 6 wk. Ultrastructural examination of animals receiving cationic BSA revealed pure, extensive formation of dense deposits along the lamina rara externa of the glomerular basement membrane whereas such deposits were absent or rare in animals injected with the anionic or native BSA. Albuminuria was significantly greater at 6 wk in the groups receiving cationic BSA with a mean of 280 mg/24 h compared with 53 mg/24 h in the combined groups injected with anionic or native BSA. Blood urea nitrogen values were similar in all groups at 2 and 4 wk but higher in the animals receiving cationic BSA at 6 wk. These experiments describe the reproducible induction of epimembranous immune deposits by administration of an exogenous cationic antigen. They suggest that antigenic charge can play an important role in the pathogenesis of membranous nephropathy by permitting direct glomerular binding of an antigen and predisposing to in situ immune complex formation.

Albuminuria↗