The first thrombocytopenia cases related to the human immunodeficiency virus (HIV) were described even before its isolation in 1983. Subsequently, multiple mechanisms have been proposed to elucidate the etiology of thrombocytopenia. In addition to other types of cytopenia affecting patients with HIV, thrombocytopenia is observed in about 10–50% HIV patients as one of the first clinical signs of infection. Thus, in this review we aim to summarize the mechanisms proposed for thrombocytopenia since the discovery of HIV, and especially the innovations in the field in recent years. Among the different mechanisms suggested for HIV-related thrombocytopenia, there is emphasis on the accelerated destruction of platelets (PLTs) due to the action of immune complexes, and the presence of anti-PLT and anti-HIV antibodies that cross-react with the PLT membrane. There are also secondary causes of thrombocytopenia, such as the effect of drugs and opportunistic diseases associated with HIV.

Surgically assisted rapid maxillary expansion increases the minor cross-sectional areas and volume of the nasal cavities. Acoustic rhinometry is an objective method for evaluating the geometry of the nasal cavity in patients with transverse maxillary deficiency.

Introduction: Cytomegalovirus (CMV) infection is a matter of concern for blood bank professionals and blood transfusion recipients, especially in cases of transfusions to neonates and immunocompromised patients. Thus, the present study aimed to determine the seroprevalence of CMV IgG and IgM antibodies among blood donors in the City of Lages, in the mountain region of Santa Catarina, southern Brazil, and to investigate possible associations between the socioeconomic characteristics of donors and CMV serological status. Methods: A seroepidemiological cross-sectional study was conducted on 1,045 blood samples from donors that were used in serological screening over a one-year investigation. All the analyses were conducted using the microparticle enzyme immunoassay with Biokit® reagents (Barcelona, Spain), in accordance with the manufacturer's instructions. Results: Anti-CMV IgG seroprevalence in the sample studied was 96.4% (95% CI: 95.23 -97.50) and that of anti-CMV IgM was 2.3% (95% CI: 1.39 -3.20). There were no statistically significant associations between the presence of antibodies and the socioeconomic characteristics of donors. Conclusions: The blood donors in the study region had high seroprevalence of anti-CMV IgG. Thus, blood component screening strategies and careful indication for blood transfusions require special attention among healthcare professionals as part of the actions for prevention and reduction of primary infections caused by CMV.

Hepatitis E virus (HEV) causes acute and chronic hepatitis in organ transplant recipients. Serological evidence for HEV infection has been discovered in various population groups in Brazil, and a single acute case has been confirmed. To date, however, no cases of HEV infection in immunocompromised patients have been reported in Brazil. This study aimed to identify and characterize hepatitis E cases in renal transplant recipients in Brazil. A retrospective study was performed on 96 serum samples from renal transplant recipients with unexplained liver enzymes elevation. Three confirmed cases of HEV infection were identified that lacked seroconversion to HEV IgG antibodies. The prevalence of HEV in these patients was 3.1%. Using a sequence analysis of a 304-nucleotide fragment within ORF2, the strains were classified as genotype 3 with a low percent identity to previously characterized strains. This is the first report of hepatitis E infection in renal transplant recipients in Brazil, and the data indicate that a novel genotype 3 subvariant may be present and that further investigation is necessary to characterize the circulating HEV strains. In this setting, HEV infection should be considered as a potential cause of abnormal liver tests of unknown origin.

The chronic course of hepatitis E virus infection in immunosuppressed patients has been recently documented; however, clinical features and factors associated with this occurrence are not well known. The aim of this study was to evaluate the prevalence of previous or current HEV infection in renal transplant patients. One hundred ninety-two kidney transplant patients were studied and classified in three groups: G1-infected with hepatitis B and/or C virus; G2-patients with elevated ALT; G3-patients with normal ALT and no hepatotropic virus infection. Demographic, epidemiologic and clinical characteristics were compared between the groups. Patients with HEV infection (previous or current) were also compared to those who tested negative for HEV. HEV infection was detected using serologic (anti-HEV IgG) and molecular (HEV RNA) methods. Anti-HEV IgG was positive in 28 (15%) while HEV RNA was positive in 20 (10%). When both markers were considered, 44 (23%) patients showed evidence of previous or current HEV infection. However, both markers were concomitantly positive in only four cases (2%). In the comparative analysis, patients infected with HBV and/or HCV showed lower frequency of anti-HEV IgG (P = 0.009). There was no difference regarding demographic, epidemiologic and laboratory variable between viremic and non-viremic patients. In conclusion, past and current infection with HEV was a frequent finding among renal transplant recipients. Actively infected patients (HEV RNA positive) did not present distinct demographic and epidemiological characteristics or laboratory alterations suggestive of underlying liver damage. Therefore, infection with HEV can only be detected in immunosuppressed patients by systematic investigation of HEV RNA.