Helio H. Caiaffa-Filho

Trypanosoma cruzi parasitemia in chronic Chagas disease : Comparison between human immunodeficiency virus (HIV)-positive and HIV-negative patients

This study evaluated Trypanosoma cruzi parasitemia in persons with chronic Chagas disease, compared the parasitemia in human immunodeficiency virus (HIV)-positive and -negative subjects, and, for HIV-positive subjects, analyzed the association between parasitemia and occurrence of acquired immunodeficiency syndrome-defining illnesses, CD4 cell counts, HIV loads, and antiretroviral therapy. In total, 110 adults with chronic Chagas disease (29 HIV positive, 81 HIV negative) were studied. T. cruzi parasitemia was evaluated by xenodiagnosis, blood culture, and direct microscopic examination of blood. T. cruzi parasitemia was detected significantly more frequently in HIV-positive than in HIV-negative subjects (odds ratio, 12.3; 95% confidence interval, 3.7-41.2). HIV-positive patients also had higher levels of parasitemia. No statistically significant association was seen between parasitemia and the variables of interest among the HIV-positive subjects.

Metallo‐beta‐lactamases among imipenem‐resistant Pseudomonas aeruginosa in a brazilian university hospital

INTRODUCTION: Imipenem‐resistant Pseudomonas aeruginosa resulting from metallo‐β‐lactamases has been reported to be an important cause of nosocomial infection and is a critical therapeutic problem worldwide, especially in the case of bacteremia. OBJECTIVES: To determine the frequency of metallo‐β‐lactamases among imipenem‐resistant Pseudomonas aeruginosa isolates and to compare methods of phenotypic and molecular detection. METHODS: During 2006, 69 imipenem‐resistant Pseudomonas aeruginosa samples were isolated from blood and tested for metallo‐β‐lactamase production using phenotypic methods. Minimal Inhibitory Concentratrions (MIC) (µg/mL) was determined with commercial microdilution panels. Pulsed Field Gel Electrophoresis (PFGE) was performed among metallo‐β‐lactamase producers. RESULTS: Of all the blood isolates, 34.5% were found to be imipenem‐resistant Pseudomonas aeruginosa. Positive phenotypic tests for metallo‐β‐lactamases ranged from 28%‐77%, and Polymerase Chain Reaction (PCR) were positive in 30% (of note, 81% of those samples were blaSPM‐1 and 19% were blaVIM‐2). Ethylenediamine tetracetic acid (EDTA) combinations for the detected enzymes had low kappa values; thus, care should be taken when use it as a phenotypic indicator of MBL. Despite a very resistant antibiogram, four isolates demonstrated the worrisome finding of a colistin MIC in the resistant range. PFGE showed a clonal pattern. CONCLUSION: Metallo‐β‐lactamases among imipenem‐resistant Pseudomonas aeruginosa were detected in 30.4% of imipenem‐resistant Pseudomonas aeruginosa isolates. This number might have been higher if other genes were included. SPM‐1 was the predominant enzyme found. Phenotypic tests with low kappa values could be misleading when testing for metallo‐β‐lactamases. Polymerase Chain Reaction detection remains the gold standard.

Methicillin-resistant Staphylococcus aureus carrying SCCmec type II was more frequent than the Brazilian endemic clone as a cause of nosocomial bacteremia

Fifty consecutive MRSA blood isolates were evaluated: 30(60%) carried SCCmec type II (single PFGE clone; sequence type 5 or ST105); 12 (26%), IV; 5 (10%), III; 3 (6%), I. Brazilian endemic clone, carrying SCCmec type III, has been the main nosocomial clone in Brazil; however, this study showed that a clone carrying type II predominated.

Early diagnosis and correlations of sexually transmitted infections among women in primary care health services

INTRODUCTION Sexually Transmitted Infections (STIs) in women remain a public health challenge due to high prevalence, difficulties to implement early diagnosis strategies and high rates of complications. OBJECTIVE Identify the prevalence of STIs among users of a primary health care clinic in São Paulo. METHODS Women, 18 to 40 years of age, were invited to self-collect vaginal specimens to be tested for Chlamydia trachomatis, Neisseria gonorrhoeae, and Trichomonas vaginalis by Polymerase Chain Reaction (PCR). Women were also invited to answer a demographic and sexual history questionnaire, either on the computer or face-to-face. RESULTS The prevalence of STIs obtained from the 781 women included in the study was: Chlamydia trachomatis: 8.4%, Neisseria gonorrhoeae: 1.9%, and Trichomonas vaginalis: 3.2%. Thirteen percent tested positive for at least one out of the three STIs. The variables associated independently with a higher risk of STIs were: age under 20-years-old, more than two lifetime sexual partners, and self-perception of STI risk. The use of condoms as a contraceptive method proved to be a protective factor. CONCLUSION The high prevalence found among these women indicates the need for the implementation of STI screening strategies in primary care settings in Brazil.

CD4/CD8 Ratio Predicts Yellow Fever Vaccine-Induced Antibody Titers in Virologically Suppressed HIV-Infected Patients.

Background:Yellow fever vaccine (YFV) induces weaker immune responses in HIV-infected individuals. However, little is known about YFV responses among antiretroviral-treated patients and potential immunological predictors of YFV response in this population. Methods:We enrolled 34 antiretroviral therapy (ART)-treated HIV-infected and 58 HIV-uninfected adults who received a single YFV dose to evaluate antibody levels and predictors of immunity, focusing on CD4+ T-cell count, CD4+/CD8+ ratio, and Human Pegivirus (GBV-C) viremia. Participants with other immunosuppressive conditions were excluded. Results:Median time since YFV was nonsignificantly shorter in HIV-infected participants than in HIV-uninfected participants (42 and 69 months, respectively, P = 0.16). Mean neutralizing antibody (NAb) titers was lower in HIV-infected participants than HIV-uninfected participants (3.3 vs. 3.6 log10mIU/mL, P = 0.044), a difference that remained significant after adjustment for age, sex, and time since vaccination (P = 0.024). In HIV-infected participants, lower NAb titers were associated with longer time since YFV (rho: −0.38, P = 0.027) and lower CD4+/CD8+ ratio (rho: 0.42, P = 0.014), but not CD4+ T-cell count (P = 0.52). None of these factors were associated with NAb titers in HIV-uninfected participant. GBV-C viremia was not associated with difference in NAb titers overall or among HIV-infected participants. Conclusions:ART-treated HIV-infected individuals seem to have impaired and/or less durable responses to YFV than HIV-uninfected individuals, which were associated with lower CD4+/CD8+ ratio, but not with CD4+ T-cell count. These results supports the notion that low CD4+/CD8+ ratio, a marker linked to persistent immune activation, is a better indicator of functional immune disturbance than CD4+ T-cell count in patients with successful ART.

A Double-Blinded, Prospective Study to Define Antigenemia and Quantitative Real-Time Polymerase Chain Reaction Cutoffs to Start Preemptive Therapy in Low-Risk, Seropositive, Renal Transplanted Recipients

Background Cytomegalovirus (CMV) disease occurs in 16% to 20% of low-risk, CMV-positive renal transplant recipients. The cutoffs for quantitative real-time polymerase chain reaction (qPCR) or phosphoprotein (pp65) antigenemia (pp65emia) for starting preemptive therapy have not been well established. Methods We measured qPCR and pp65emia weekly from day 7 to day 120 after transplantation, in anti-CMV immunoglobulin G–positive donor and recipient pairs. Patients and physicians were blinded to the test results. Suspicion of CMV disease led to the order of new tests. In asymptomatic viremic patients, the highest pp65emia and qPCR values were used, whereas we considered the last value before diagnosis in those with CMV disease. Results We collected a total of 1,481 blood samples from 102 adult patients. Seventeen patients developed CMV disease, 54 presented at least one episode of viremia that cleared spontaneously, and 31 never presented viremia. Five patients developed CMV disease after the end of the study period. The median (95% confidence interval) pp65emia and qPCR values were higher before CMV disease than during asymptomatic viremia (6 [9–82] vs. 3 [1–14] cells/106 cells; P<0.001 and 3,080 [1,263–15,605] vs. 258 [258–1,679] copies/mL; P=0.008, respectively). The receiver operating characteristic curve showed that pp65emia 4 cells/106 cells or greater showed a sensitivity and specificity to predict CMV disease of 69% and 81%, respectively (area, 0.769; P=0.001), with a positive predictive value of 37% and a negative predictive value of 93%. For qPCR 2,000 copies/mL or higher, the positive predictive value and negative predictive value were 57% and 91%, respectively (receiver operating characteristic area, 0.782; P=0.000). Conclusion With these cutoffs, both methods are appropriate for detecting CMV disease.

Performance of a Rapid Self-Test for Detection of Trichomonas vaginalis in South Africa and Brazil

ABSTRACT Women participating in studies in Brazil (n = 695) and South Africa (n = 230) performed rapid point-of-care tests for Trichomonas vaginalis on self-collected vaginal swabs. Using PCR as the gold standard, rapid self-testing achieved high specificity (99.1%; 95% confidence interval [CI], 98.2 to 99.6%) and moderate sensitivity (76.7%; 95% CI, 61.4 to 88.2%). These tests may be considered an alternative to syndromic management in resource-poor settings.

CD4/CD8 Ratio and KT Ratio Predict Yellow Fever Vaccine Immunogenicity in HIV-Infected Patients

Background HIV-infected individuals have deficient responses to Yellow Fever vaccine (YFV) and may be at higher risk for adverse events (AE). Chronic immune activation–characterized by low CD4/CD8 ratio or high indoleamine 2,3-dioxygenase-1 (IDO) activity—may influence vaccine response in this population. Methods We prospectively assessed AE, viremia by the YFV virus and YF-specific neutralizing antibodies (NAb) in HIV-infected (CD4>350) and -uninfected adults through 1 year after vaccination. The effect of HIV status on initial antibody response to YFV was measured during the first 3 months following vaccination, while the effect on persistence of antibody response was measured one year following vaccination. We explored CD4/CD8 ratio, IDO activity (plasma kynurenine/tryptophan [KT] ratio) and viremia by Human Pegivirus as potential predictors of NAb response to YFV among HIV-infected participants with linear mixed models. Results 12 HIV-infected and 45-uninfected participants were included in the final analysis. HIV was not significantly associated with AE, YFV viremia or NAb titers through the first 3 months following vaccination. However, HIV–infected participants had 0.32 times the NAb titers observed for HIV-uninfected participants at 1 year following YFV (95% CI 0.13 to 0.83, p = 0.021), independent of sex, age and prior vaccination. In HIV-infected participants, each 10% increase in CD4/CD8 ratio predicted a mean 21% higher post-baseline YFV Nab titer (p = 0.024). Similarly, each 10% increase in KT ratio predicted a mean 21% lower post-baseline YFV Nab titer (p = 0.009). Viremia by Human Pegivirus was not significantly associated with NAb titers. Conclusions HIV infection appears to decrease the durability of NAb responses to YFV, an effect that may be predicted by lower CD4/CD8 ratio or higher KT ratio.

Chikungunya in kidney transplant recipients: A series of cases

Chikungunya (CHIK) is a mosquito-borne virus (CHIKV) infection that recently appeared in the Americas and thousands of confirmed cases have been reported in Brazil since the first autochthonous cases were reported in September 2014. We reported four cases of CHIK in kidney transplant recipients. The diagnosis was confirmed by positive CHIKV real-time polymerase chain reaction in two cases and positive CHIKV-IgM serology in two patients. The time between transplantation and CHIKV infection ranged from 2 to 11 years. All of them had arthralgia, and 3 of them had fever. Other symptoms were mild conjunctivitis, rash, and retro-orbital pain. Kidney function remained stable in all cases. In three patients prednisone doses were temporally increased and the symptoms disappeared concurrently with the increase of the dose. As for the fourth patient, the prednisone dose remained unchanged and yet she improved. Other immunosuppressive drugs were not changed for the four cases. As far as we know, there are only two previously reported cases of CHIK among solid organ transplant recipients besides the four cases reported here. Despite the small number of cases, we can speculate that the use of immunosuppression might have played a role in the paucity of symptoms and the gradual complete recovery with no complication.

Implementing human papillomavirus testing in a public health hospital : challenges and opportunities

Objectives: Robust evidence now supports human papillomavirus (HPV) testing as a more effective option to screening and as more sensitive than cytology in detecting high-grade cervical intraepithelial neoplasia . Our goal was to analyze the performance of the Hybrid Capture II (HC2) assay for high-risk HPV (hrHPV) in women undergoing gynecological examination at a public health hospital as part of the evaluation of HPV screening as an alternative or complement to cytology. Study Design: This analysis is a subset of a cross-sectional study carried out at a large public hospital serving a predominantly low-resource population. A total of 705 women were enrolled; the sensitivity and specificity of each test were estimated and compared. Results: The analysis identified 272 hrHPV-positive women (mean age 36.3 years) and 433 hrHPV-negative women (mean age 41.2 years). HPV testing showed a significantly increased sensitivity of the HC2 assay versus cytology (84.5 vs. 69.7%; p < 0.0001) but a lower specificity (49.90 vs. 88.78%; p < 0.0001). Conclusion: The combination of both methods seems to be useful in improving detection of cervical lesions.