The CCR5 molecule, a chemokine receptor, is the most important co-receptor for macrophage-tropic HIV-1. A 32-bp deletion in the gene encoding CCR5 (CCR5-del32) confers nearly complete resistance to HIV-1 infection in homozygotes, and slows the rate of progression to AIDS in heterozygous adults. The aim of this study was to describe the CCR5 genotypes and the characteristics of HIV disease progression in perinatally infected children. From a total of 51 children analyzed for the CCR5-del32 mutation, 18 (35%) were considered to be rapid progressors, 28 (55%) were moderate progressors and 5 (10%) were slow progressors. A portion of the CCR5 gene was amplified by PCR from genomic DNA followed by agarose gel electrophoresis. Forty-nine children (96%) carried the homozygous wild type genotype for CCR5 while 2 (4%) carried the heterozygous wt/del32 genotype. In the population studied, the CCR5 genotype was unable to account for the differences in pattern of the disease progression among the three groups (rapid, moderate and slow progressors), and the allele frequency of CCR5-del32 was too low to allow statistical comparisons with adequate resolving power. Studies on larger populations may help to further elucidate the role of this allele and other host factors in the regulation of HIV-1 pathogenesis in children.

Foram acompanhados 27 pacientes submetidos a transplante renal para avaliação do comportamento dos anticorpos IgM e IgG CMV-específicos. Dos 27 casos estudados, 17 (63,0%) tinham anticorpos IgG, detectados pela reação de fixação de complemento (RFC), antes de serem submetidos ao transplante, e 10 (37,0%) eram soro negativos. A pesquisa de anticorpos IgM (técnica de imunofluorescência indireta) foi negativa em todas as amostras pré transplante. Num período de acompanhamento que variou de 28 a 425 dias (média de 115 dias) após o transplante, observou-se que 20 dos 27 (74,1%) apresentaram evidências sorológicas de infecçáo pelo CMV, ocorrendo a maioria dos casos (14/20, 70%) em pacientes que já tinham anticorpos para o CMV antes do transplante. A pesquisa de anticorpos IgM CMV-específicos foi positiva em 12 dos 14 pacientes com evidências sorológicas de reinfecção ou reativação da infecção pelo CMV, e em 100% (6/6) dos pacientes com infecção primária. Dentre os 10 pacientes acompanhados por mais de 4 meses, somente 1 (10%) negativou o IgM neste período.

Twenty-seven patients who underwent renal allograft transplants were periodically screened for the presence of IgM and IgG cytomegalovirus (CMV) antibodies. Before transplantation, 17 (63%) had IgG antibodies by complement fixation and 10 (37%) were seronegative. Immunofluorescent IgM CMV-antibodies were absent in all pre-transplant sera. During a follow-up period of 28 to 425 days (median of 115 days), 20 (74%) developed serologic evidence of CMV infection. Of these, 6 (30%) were primary and 14 (70%) secondary (reactivation or reinfection). IF-IgM antibodies were seen in 12 out of 14 patients with secondary CMV infection and in all patients with primary infection. IgM antibodies became negative in one out of 10 IgM-positive patients who were followed-up for 4 months or more.