Evaluation of pretransplant influenza vaccination in hematopoietic SCT: a randomized prospective study.

Pretransplant influenza vaccination of the donor or allogeneic hematopoietic SCT (HSCT) candidate was evaluated in a randomized study. One hundred and twenty-two HSCT recipients and their donors were assigned to three randomization groups: no pretransplant vaccination (n=38), donor pretransplant vaccination (n=44) or recipient pretransplant vaccination (n=40). Specific IgG was assessed by both hemagglutinin inhibition (HI) and, in 57 patients, by an indirect influenza-specific ELISA at specified times after HSCT. Vaccinated donors had seroprotective HI titers for Ags H1 and H3 (P<0.001) compared with the other groups at the time of donation. The titers against H1 (P=0.028) and H3 (P<0.001) were highest in the pretransplant recipient vaccination group until day 180 after transplantation. A significant difference was found in the specific Ig levels against pandemic H1N1 at 6 months after SCT (P=0.02). The mean IgG levels against pandemic H1N1 and generic H1N1 and H3N2 were highest in the pretransplant recipient vaccination group. We conclude that pretransplant recipient vaccination improved the influenza-specific seroprotection rates.

An outbreak of respiratory syncytial virus infection in hematopoietic stem cell transplantation outpatients: good outcome without specific antiviral treatment.

BACKGROUND: Respiratory syncytial virus (RSV) is a common cause of seasonal respiratory viral infection in hematopoietic stem cell transplantations (HSCT) patients. The efficacy of treatment, however, remains controversial. We describe an outbreak of 31 cases of RSV that occurred in an HSCT outpatient care unit in the fall season from March through May 2010, with a good outcome without any specific antiviral treatment. METHODS: During these 3 months, 222 nasal wash samples were tested and, of these, 31 outpatients were positive for RSV. In 2009, 99 samples had been tested and only 10 outpatients were positive for RSV in the same period. RESULTS: Seven (22.5%) patients had severe neutropenia (<500 cells/µL); severe lymphopenia (<200 cells/µL) was present in 13 (41.9%) patients, and 14 (45%) had received intravenous broad-spectrum antibiotics. Hospitalization was necessary only for 8 patients (25.8%); 20 had lower respiratory tract infection (64.5%). Only 1 patient died as a result of proven invasive aspergillosis. CONCLUSION: This report suggests that HSCT outpatients with no risk factors may not always require specific treatment for RSV.

Antibody response to the non-adjuvanted and adjuvanted influenza A H1N1/09 monovalent vaccines in renal transplant recipients.

BACKGROUND: The 2009 pandemic influenza A (H1N1) virus spread rapidly throughout Brazil. Non-adjuvanted and the adjuvanted influenza A H1N1/09 monovalent vaccine were recommended as a single dose to persons at risk including renal transplant recipients (RTR). We analyzed the safety and the immune response of 2 influenza A H1N1/09 monovalent vaccines in RTR, and identified factors influencing the immune response. METHODS: A total of 78 RTR received a single dose of either influenza A H1N1 2009 monovalent AS03-adjuvanted vaccine or a non-adjuvanted vaccine, and 58 healthy controls received a single dose of non-adjuvanted vaccine. Antibody responses to influenza A H1N1 were measured by hemagglutination inhibition assay and were compared between groups on the day of vaccination and 21-30 days thereafter, using geometric mean titer (GMT), and seroprotection (SP) and seroconversion (SC) rates. RESULTS: Among RTR, after adjuvanted and non-adjuvanted H1N1 vaccination, the SP rate increased from 16.7% to 61.7% (P < 0.001) and to 50% (P < 0.001), and SC rates were 61.7% and 50%, respectively. For healthy controls, SP rate increased from 25.8% to 89.7% (P < 0.001), and SC rate was 87.9% after vaccination. Pre-vaccination GMT for the adjuvanted and non-adjuvanted RTR vaccine groups and healthy controls was 9.7 (95% confidence interval [CI] 7.3-13.1), 8.9 (95% CI 5.4-14.7), and 12.5 (95% CI8.7-18.2), and significantly increased to 49.8 (95% CI 31.3-79.4, P < 0.001), 43.2 (95% CI 16.3-114.4, P < 0.001), and 323.8 (95% CI 213.9-490.2, P < 0.001), respectively. Deceased-donor type transplant significantly reduced SP (odds ratio [OR] = 4.62, 95% CI 1.36-15.69, P = 0.014) and SC (OR = 6.29, 95% CI 1.89-20.98, P = 0.003) rates, and younger age positively affected SP (OR = 0.11; 95% CI 0.03-0.04, P = 0.001). Adverse events were mild, and renal function showed no change post vaccination. CONCLUSION: RTR vaccinated with either an adjuvanted or non-adjuvanted monovalent influenza vaccine presented poor response compared with healthy controls. Post-vaccination adverse events were mild, and no rejection episode or renal dysfunction was observed.

Seroprevalence and risk factors of caprine toxoplasmosis in Minas Gerais, Brazil.

The objective of this work was to carry out a study on caprine toxoplasmosis in the state of Minas Gerais, Brazil. To determine the prevalence of toxoplasmosis in goats in Minas Gerais, 767 sera from goats were tested by ELISA (enzyme-linked immunosorbent assay) and IFAT (indirect fluorescence antibody test). The prevalence of antibodies to Toxoplasma gondii was 43.0% and 46.0% by ELISA and IFAT, respectively. It was observed that 26.8% of the goats show low-avidity IgG to T. gondii. These results suggest the presence of animals in recent phase of toxoplasmosis in Minas Gerais. The risk factors for toxoplasmosis in goats were: age over 36 months (OR=1.21; IC 95% 1.02-1.44), use of pen (OR=1.83; IC 95%1.01-3.31) and pure breed animals (OR=2.49; IC 95% 1.11-5.59).

Loss of hepatitis A virus antibodies after bone marrow transplantation.

Reimmunization guidelines have recommended the inactivated HAV vaccine for hematopoietic stem cell transplant (HSCT) recipients living in or traveling to areas where hepatitis A is endemic. As a shift from high to medium hepatitis A endemicity has been observed in several countries in Latin America, we conducted a retrospective study to evaluate the prevalence of hepatitis A pre-bone marrow transplant (BMT) and the loss of specific antibodies in consecutive stored serum samples from 77 BMT recipients followed up from 82 to 1530 days. The prevalence of HAV antibodies was 92.2% before BMT. As vaccine was not available in Brazil when the samples were taken, it was assumed that this prevalence reflects natural infection. Survival analysis showed that the probability of becoming seronegative was 4.5% (+/-2.6%), 7.9% (+/-3.4%), 10.1% (+/-4.0%), 23.4% (+/-9.6%) at 1, 2, 3 and 4 years after transplant, respectively. The loss of HAV antibodies was significantly associated with longer follow-up (P=0.0015), younger age (P=0.049) and acute graft-versus-host disease (P=0.035). As most reimmunization protocols start around day +365, in developing countries with similar HAV endemicity, BMT recipients should have serological screening before HAV vaccination and the inactivated vaccine should be advised to those seronegative.

The benefit of influenza vaccination after bone marrow transplantation.

Influenza vaccine is recommended yearly for recipients after the sixth month of BMT. Although a higher risk of complications of influenza is expected to occur in BMT patients, no study has addressed the clinical efficacy of influenza vaccination in this setting. Focusing on the clinical benefits of influenza vaccination, we evaluated the risk factors for influenza infection in a cohort of 177 BMT recipients followed up for 1 year. Influenza was diagnosed in 39 patients. Multivariate analyses showed that seasonal exposure and more aggressive conditioning regimens were independently associated with increased risk for influenza. Influenza vaccination and steroid use showed a protective role. Of the 43 patients who had received BMT longer than 6 months, 19 were vaccinated (compliance rate = 44.2%) and vaccine efficacy was 80%. We conclude that influenza vaccination plays an important role in protecting BMT recipients against influenza and all efforts should be made to ensure good compliance with vaccination.

Use of Oseltamivir to control influenza complications after bone marrow transplantation.

Influenza infection can be severe in bone marrow transplant (BMT) recipients. Although yearly epidemics occur worldwide, and a higher risk of complication is expected in these patients, few studies have addressed the impact of the new neuraminidase inhibitors in the prognosis of influenza after BMT. Influenza A or B infections were found in 39 of the 66 patients (59%) showing a positive nasal wash by DFA. Influenza A was diagnosed in 18 patients and influenza B in 23 patients; two patients were infected by influenza A and B with 84- and 90-day intervals between episodes, respectively. Of the 41 episodes (61%) of influenza A or B, 25 infections occurred during the spring and summer months. Oseltamivir was introduced within 48 h of symptoms appearing. Only two patients (5.1%) developed influenza pneumonia, and no patient died of influenza. A total of 22 patients (56.4%) acquired influenza before day +180 when preventive vaccination strategies are precluded owing to poor immunogenicity of the vaccine during this period. Oseltamivir proved to be safe and appears to have played an important role in the outcome of influenza infection in this population. The therapeutic and/or prophylactic benefits of Oseltamivir in BMT recipients remain to be demonstrated in randomized, prospective trials.

Low mortality rates related to respiratory virus infections after bone marrow transplantation.

Respiratory viruses (RVs) frequently cause severe respiratory disease in bone marrrow transplant (BMT) recipients. To evaluate the frequency of RV, nasal washes were collected year-round from BMT recipients with symptoms of upper respiratory tract infection (URI). Direct immunofluorescence assay was performed for respiratory syncytial virus (RSV), influenza (Flu) A and B, adenovirus and parainfluenza (Paraflu) virus. Patients with RSV pneumonia or with upper RSV infection, but considered at high risk for developing RSV pneumonia received aerosolized ribavirin. Oseltamivir was given to patients with influenza. A total of 179 patients had 392 episodes of URI. In all, 68 (38%) tested positive: RSV was detected in 18 patients (26.4%), Flu B in 17 (25%), Flu A in 11 (16.2%) and Paraflu in 7 (10.3%). A total of 14 patients (20.6%) had multiple RV infections or coinfection. RSV pneumonia developed in 55.5% of the patients with RSV-URI. One of the 15 patients (6.6%) with RSV pneumonia died. Influenza pneumonia was diagnosed in three patients (7.3%). RSV and influenza infections peaked in fall-winter and winter-spring months, respectively. We observed decreased rates of influenza and parainfluenza pneumonia and low mortality because of RSV pneumonia. The role of antiviral interventions such as aerosolized ribavirin and new neuraminidase inhibitors remains to be defined in randomized trials.

Thermolabile and calcium-dependent serum factor interferes with polymerized actin, and impairs anti-actin antibody detection.

The detection of anti-actin (AAA) by immunofluorescence is hindered by the presence of a serum factor. To better understand how it interferes with AAA detection, we tested sera from 20 patients with autoimmune hepatitis, and from 21 healthy adults, diluted 1:10 and prepared as follows: (A) diluted with PBS; (B) inactivated at 56 degrees C, and diluted with PBS; (C) diluted with 34 mM EDTA/PBS; (D) heated and diluted with EDTA/PBS. To reveal AAA, a fluorescein-labelled anti-human IgG was used in the process of indirect immunofluorescence. In a parallel assay, the substrate, acetone-fixed human fibroblasts, was preincubated with sera prepared as if it were to identify AAA, but instead, a rhodamine-phalloidin was used to identify F-actin, by direct immunofluorescence. All sera from patients were reactive to AAA when heat-inactivated and/or calcium-chelated, and 60% of them when diluted with unmodified sera (P=0.004). F-actin continued to be present after preincubation with heat-inactivated or calcium-chelated sera from patients and healthy controls, and in 41.5% of reactions with unmodified serum (P=0.0000001). The heat inactivation and the calcium chelation were both efficient procedures for maintaining the microfilament structure intact after serum incubation and, therefore, for identifying AAA.

Effect of highly active antiretroviral therapy on cytomegalovirus antigenaemia in AIDS patients.

To assess the effect of highly active antiretroviral therapy (HAART) on cytomegalovirus (CMV) antigenaemia in AIDS patients, 70 patients with CD4+ cell counts < or = 50/mm3 and positive anti-(CMV) immunoglobulin G (IgG) were tested at 15-30 day intervals for CMV antigenaemia. We selected those patients who had been followed up for more than 3 months. Three patient profiles were defined: A, followed up before the introduction of HAART; B, followed up before and after the use of HAART; and C, followed up after the use of HAART. Thirty-nine patients were included, 12 in group A, 17 in group B, and 10 in group C. Group A patients presented a lower median CD4+ cell count compared with groups B and C patients (9, 122 and 127 cells/mm3, respectively), with the increase in the last 2 groups being related to the use of HAART (P<0.001). A lower proportion of positive antigenaemia was observed in group B after the introduction of HAART compared with the time before HAART (P=0.02). HAART caused an immunological improvement and was found to be associated with negativity of CMV antigenaemia.