Search PubMed⌕ Search

Biomedical subjects

K Solez

Publications and source records attributed to K Solez.

At least 37 records · Page 2Linked to original sources
PubMed1997

A UK-wide trial of the Banff classification of renal transplant pathology in routine diagnostic practice.

BACKGROUND: The Banff classification of renal transplant pathology has gained wide support since its introduction in 1993. There have been several studies which have tested its usefulness in the context of research-oriented centres. We sought to evaluate its use in a wider context. METHODS: We recruited pathologists from all but one of the renal transplant centres in the UK. Sections were circulated from 21 selected, 'difficult' cases, in all of which the clinical question was confirmation or exclusion of acute rejection, and in all of which a definite diagnosis had been obvious from the subsequent clinical course. Participants were asked first to diagnose or exclude acute rejection by their usual approach, then to apply the Banff classification. No clinical information was given beyond the time since engraftment, in order to confine the evaluation to the morphological features present in the sections. At the end of the study the subjective impressions of the participants were sought using a structured questionnaire. RESULTS: Using the Banff classification produced no detectable difference in the number of 'correct' diagnoses when compared with a conventional approach, irrespective of whether the 'correct' diagnosis is based on retrospective clinical information or on the consensus opinion of the pathologists involved, and irrespective of where in the Banff schema one applies a 'cut-off' for the diagnosis of acute rejection. However, the reproducibility of the diagnoses was improved. The results suggest that in the Banff classification the best 'cut-off' for the diagnosis of acute rejection is between Banff category 3 and category 4, although in this difficult area we found a large improvement in diagnostic accuracy if input of clinical information occurs. CONCLUSIONS: The improved reproducibility justifies the use of the Banff classification to harmonise approaches between centres, especially in research projects. While there are good reasons also to adopt it in routine diagnostic practice, further refinement is necessary before an improvement in the accuracy of diagnosis can be demonstrated.

Diagnostic Errors↗
PubMed1997

Renal transplant biopsy: what does it tell?

The value of the renal allograft biopsy has been significantly enhanced by several developments in 1997 including the following: the first convincing demonstration that molecular biology techniques can be applied to renal allograft tissue to obtain a diagnosis of acute rejection with high sensitivity and specificity; the development of an improved, internationally agreed classification of kidney transplantation pathology ('Banff 1997'); and significant new insights into the specific pathology of chronic rejection, involving splitting and lamination of peritubular capillary basement membranes and the presence of increased apoptotic cell death. Although it is predictable that long-term technology might eliminate the need for renal allograft biopsies altogether, in the short term these new breakthroughs will greatly increase the value of this procedure in the management of renal transplant patients.

Biopsy↗
PubMed1996

Pathologic features of acute renal allograft rejection associated with donor-specific antibody, Analysis using the Banff grading schema.

Alloantibody frequently appears during the immune response to alloantigens in renal transplant recipients. We studied whether the presence of antibody against donor class I antigens correlated with the clinical and pathologic features of acute rejection episodes. We identified patients who had (1) clinical evidence of acute rejection, (2) a renal biopsy showing pathologic features of acute rejection, defined by the Banff criteria, and (3) pre- and posttransplant sera screened against donor T cells. We divided these patients into those with or without donor-specific alloantibody reactive with donor T cells. Of 44 patients with biopsy-proven rejection, 20 were antibody negative (Ab-R) and 24 were antibody positive (Ab+R). The biopsies from Ab+R patients had a higher incidence of severe vasculitis (P=0.0009) and glomerulitis (P=0.01). Fibrin thrombi in the glomeruli and/or vessels, fibrinoid necrosis, and dilatation of peritubular capillaries were also more frequent in the Ab+R group. Infarction was present in biopsy specimens from 9/24 Ab+R patients versus none in the Ab-R group (P=0.002). The Ab+R biopsy specimens more often had polymorphonuclear leukocytes in the peritubular capillaries (P=0.003). In contrast, specimens of Ab-R patients showed tubulitis more often than the specimens of Ab+R patients: moderate and severe tubulitis was present in 19/20 (95%) Ab-R patients versus 12/24 (50%) Ab+R patients (P=0.002). Graft loss was increased in Ab+R patients, particularly in the first 3 months (12/24 compared with 3/20, P=0.025). Thus, during biopsy-proven acute rejection episodes, anti-class I antibody correlates with severe vascular lesions, glomerulitis, and infarction, whereas more severe tubulitis predominates in rejection episodes without antibody.

Adult↗
PubMed1995

Reproducibility of the Banff classification of renal allograft pathology. Inter- and intraobserver variation.

The present study was undertaken to investigate the inter- and intraobserver variation in use of the scoring system for glomerulitis, vasculitis, interstitial inflammation, tubulitis and arteriolar hyalinosis that is an essential part of the recently proposed Banff classification of renal allograft biopsies. Seventy-seven biopsies done less than 90 days after transplantation were included. The scoring was done blindly by five pathologists on biopsies stained with H&E and PAS. The volume fraction of interstitial inflammation was estimated. Spearman rank correlation coefficient and kappa values were used for the evaluation of reproducibility. The results of both inter- and intraobserver variability showed a good correlation and reasonable kappa values for vasculitis, interstitial inflammatory infiltration, and tubulitis. Less-good correlation was found for glomerulitis and arteriolar hyalinosis. The interobserver kappa score for grading of the rejection severity was 0.40 overall but 0.56 when only presence or absence of acute rejection was considered and 0.66 for presence or absence of vasculitis. Weighted kappa values for interobserver vasculitis score and rejection grading were 0.58 and 0.55, respectively. A strong association existed between the volume fraction of interstitial inflammation and the semiquantitative scoring for interstitial inflammation. In conclusion, the good correlations for the key elements in the grading of the allograft biopsies in the present classification system, confirmed the utility of the defined criteria for grading rejection. More precisely defined criteria or simplification of the scoring system are needed for glomerulitis and arteriolar hyalinosis--parameters not used in the diagnosis of rejection.

Biopsy↗
PubMed1995

Adult hemolytic-uremic syndrome. A review of 37 cases.

BACKGROUND: Adult hemolytic-uremic syndrome is a serious, poorly understood disease with a high and variable mortality. We studied several demographic, clinical, and treatment variables, related them to outcome, and developed a new classification. METHODS: We analyzed data from 37 patients admitted from 1981 to 1991 who fulfilled four criteria (age > 16 years, microangiopathic hemolytic anemia, creatinine level > 150 mumol/L [> 1.7 mg/dL], and no artificial heart valve). Three outcome variables were studied (survival vs death, recurrence vs no recurrence, and chronic renal failure vs no chronic renal failure). RESULTS: Eleven (30%) of the patients died, 10 (27%) needed dialysis, five (14%) developed chronic renal failure, and nine (24%) had recurrent episodes. Patients who presented with colitis did not die or have recurrences, but they developed chronic renal failure as often as other patients. Patients with hemolytic-uremic syndrome secondary to other diseases had the worst survival and the most recurrences. Those without any triggering factor (primary cases) were in between. In multivariate analysis, hemolytic-uremic syndrome secondary to colitis, a higher white blood cell count at admission, and a high maximum mean arterial pressure were associated with good survival prognosis. CONCLUSIONS: The persistence of the trigger of adult hemolytic-uremic syndrome sets the stage for outcome. If the trigger is transient (such as Escherichia coli colitis), the disease will not recur and is rarely lethal. If no trigger is apparent (primary hemolytic-uremic syndrome) or the trigger persists (systemic lupus erythematosus and cancer), the syndrome has a high mortality and often recurs. We suggest a new classification: (1) extrinsic hemolytic-uremic syndrome: (a) toxic, (b) infectious; (2) intrinsic hemolytic-uremic syndrome: (a) primary, (b) secondary. The use of this classification, combined with simple data obtained at presentation and a further division of the cause as transient or persistent and irreversible, may improve the selection of therapy.

Adolescent↗
PubMed1995

Endocapillary glomerulitis in the renal allograft.

Endocapillary glomerulitis is characterized by an increase in number of mononuclear cells in the glomerular capillary lumina. This lesion has been described in the early posttransplant period, but its pathogenesis, relation to conventional rejection, and prognostic impact is not well known. Using the definitions, scorings, and gradings of the Banff system for classification and grading of histopathologic changes in the renal allograft, we have analyzed 444 consecutive renal allograft biopsies from the first 90 days posttransplant. Moderate or severe glomerulitis occurred in 13.5% of the biopsies. There was a strong tendency toward clustering of glomerulitis: if one biopsy from a patient had glomerulitis, there was a high probability that it occurred in other biopsies from the same patient. There was some correlation with conventional acute rejection, but 40% of all biopsies with glomerulitis had no rejection and 53% of all biopsies with rejection had no glomerulitis. Graft function at biopsy was nil or decreased in many patients, but this could largely be explained by the independent presence of primary graft dysfunction or conventional rejection, these conditions being a frequent indication for performing a graft biopsy. Moderate or even severe glomerulitis was, however, compatible with a functioning graft. No correlation between glomerulitis and active CMV infection was found. The one-year graft survival of grafts with early posttransplant glomerulitis was 66%. If early conventional acute rejection is taken into consideration, graft survival does not seem to be influenced by the presence of glomerulitis. Early posttransplant endocapillary glomerulitis may be a peculiar pattern of rejection with a pathogenesis different from that of conventional rejection, but the present investigation does not demonstrate any adverse effects on graft function or graft prognosis.

Adolescent↗