Phasing out the pre-transplant cytotoxicity crossmatch: Are we missing something?

INTRODUCTION: The anti-human globulin-enhanced complement-dependent cytotoxicity crossmatch (AHG-CDCXM) assay has been used to assess the presence of donor-specific antibodies (DSA) in recipient's serum before kidney transplantation. The flow cytometric crossmatch (FCXM) assay was first introduced as an additional test. The aim of this study was to clinically validate the single use of the FCXM assay. METHODS: This study compared the outcomes of a cohort of kidney transplant patients that underwent FCXM only (FCXM group) versus a cohort of kidney transplant patients that underwent AHG-CDCXM (control group). RESULTS: Ninety-seven patients in the FCXM group and 98 controls were included. All crossmatches in the control group were negative. One patient in the FCXM group had a positive B cell crossmatch. One year after transplantation, there were no significant differences in patient survival (p = 0.591) and graft survival (p = 0.692) between the groups. Also, no significant difference was found in the incidence of Banff ≥ 1A acute cellular rejection episodes (p = 0.289). However, acute antibody-mediated rejections occurred in 3 controls (p = 0.028). CONCLUSION: The results showed that discontinuing the AHG-CDCXM assay does not modify the clinical outcomes in a 1-year follow-up.

Phasing out the pre-transplant cytotoxicity crossmatch: Are we missing something? / Exclusão da prova cruzada por citotoxicidade pré-transplante: estamos perdendo algo

Abstract Introduction: The anti-human globulin-enhanced complement-dependent cytotoxicity crossmatch (AHG-CDCXM) assay has been used to assess the presence of donor-specific antibodies (DSA) in recipient's serum before kidney transplantation. The flow cytometric crossmatch (FCXM) assay was first introduced as an additional test. The aim of this study was to clinically validate the single use of the FCXM assay. Methods: This study compared the outcomes of a cohort of kidney transplant patients that underwent FCXM only (FCXM group) versus a cohort of kidney transplant patients that underwent AHG-CDCXM (control group). Results: Ninety-seven patients in the FCXM group and 98 controls were included. All crossmatches in the control group were negative. One patient in the FCXM group had a positive B cell crossmatch. One year after transplantation, there were no significant differences in patient survival (p = 0.591) and graft survival (p = 0.692) between the groups. Also, no significant difference was found in the incidence of Banff ≥ 1A acute cellular rejection episodes (p = 0.289). However, acute antibody-mediated rejections occurred in 3 controls (p = 0.028). Conclusion: The results showed that discontinuing the AHG-CDCXM assay does not modify the clinical outcomes in a 1-year follow-up.

Resumo Introdução: O ensaio de prova cruzada por citotoxicidade dependente do complemento antiglobulina humana (AHG-CDCXM - do inglês anti-human globulin-enhanced complement-dependent cytotoxicity crossmatch) tem sido usado para avaliar a presença de anticorpos específicos contra o doador (DSA - do inglês donor-specific antibodies) no soro do receptor antes do transplante renal. O ensaio de prova cruzada por citometria de fluxo (CFXM) foi introduzido pela primeira vez como um teste adicional. O objetivo deste estudo foi validar clinicamente o uso único do ensaio CFXM. Métodos: Este estudo comparou os resultados de uma coorte de pacientes de transplante renal que foram submetidos apenas ao CFXM (grupo CFXM) contra uma coorte de pacientes de transplante renal submetidos ao AHG-CDCXM (grupo controle). Resultados: Foram incluídos noventa e sete pacientes no grupo CFXM e 98 controles. Todas as provas cruzadas no grupo controle foram negativas. Um paciente no grupo CFXM teve uma prova cruzada positiva para células B. Um ano após o transplante, não houve diferenças significativas na sobrevida do paciente (p = 0,591) e na sobrevida do enxerto (p = 0,692) entre os grupos. Também não foi encontrada diferença significativa na incidência de episódios de rejeição aguda celular (p = 0,289) segundo critério de Banff ≥ 1A. No entanto, rejeições agudas mediadas por anticorpos ocorreram em 3 controles (p = 0,028). Conclusão: Os resultados mostraram que a interrupção do ensaio AHG-CDCXM não modifica os desfechos clínicos em um acompanhamento de 1 ano.

Hypertension--an emerging cardiovascular risk factor in HIV infection.

Patients with HIV may have an increased risk of hypertension and cardiovascular disease (CVD). The objective of this study was to determine the prevalence and risk factors for hypertension in a population of HIV-infected patients at an HIV/AIDS clinic in southern Brazil. We reviewed medical records of 1009 HIV-infected patients aged 18 years or more in an urban HIV/AIDS clinic based in Porto Alegre, southern Brazil. Hypertension was defined according to the Eighth Joint National Committee criteria. The prevalence of hypertension in this study cohort was 22.5% (95% confidence interval, 20%-25.2%). Individuals were significantly older in the hypertensive group (P < .001). After adjustment using a Poisson regression model of all variables that presented P < .2 in the univariate analysis, the variables that were significantly associated with hypertension were only age ≥40 years and obesity. Also in this setting, dyslipidemia (P = .068) showed a tendency of association with hypertension. Compared with HIV-infected persons aged 18-39 years, those aged 40-59 years presented a 2-fold higher prevalence of hypertension (95% confidence interval, 1.2-3.3).The present study showed a high prevalence of hypertension among HIV-infected persons, similar to other studies, ranging from 13% to 45%, and also similar to the HIV-negative general population. Age and obesity were the factors associated with hypertension. Finally, the present study indicates a similar pattern of behavior and comorbidities for HIV-positive and -negative patients in relation to hypertension.