Sonia Mara Raboni

Respiratory tract viral infections in bone marrow transplant patients.

Background. Community respiratory viruses such as respiratory syncytial virus (RSV), adenovirus, influenza A, influenza B, and the parainfluenza group are frequent causes of respiratory disease in bone marrow transplant (BMT) patients. Material and Methods. During the period from March 1993 to August 1999, 810 samples of respiratory secretions, nasopharyngeal aspirate (NPA) or bronchoalveolar lavage (BAL), from 722 patients with upper respiratory infections symptoms at the BMT unit of the Federal University in the state of Paraná, Brazil were evaluated for respiratory virus infection. Results. One hundred thirty‐six (17%) samples were reactive in 62 patients. RSV was found in 30 of 62 (48%), influenza A in 14 of 62 (23%), influenza B in 9 of 62 (15%), parainfluenza group in 7 of 62 (11%), and adenovirus in 2 of 62 (3%) infected patients. The most frequent clinical manifestations were cough and fever. Pneumonia occurred in 19 of 62 (31%) cases. The mortality rate was 23 of 62 (37%), being higher among patients infected with adenovirus and influenza A. Conclusions. Infections in BMT patients occurred during the outbreak period of these viruses in the community, highlighting the need to establish surveillance measures in units with immunocompromised patients in addition to the development of sensitive and rapid diagnostic tests for the detection of these viruses in patients with respiratory symptoms.

Human metapneumovirus infection in hematopoietic stem cell transplant recipients

M.C. Debur, L.R. Vidal, E. Stroparo, M.B. Nogueira, S.M. Almeida, G.A. Takahashi, I. Rotta, L.A. Pereira, C.S. Silveira, C.M. Bonfim, S.M. Raboni. Human metapneumovirus infection in hematopoietic stem cell transplant recipients.
Transpl Infect Dis 2010: 12: 173–179. All rights reserved

Comparison of latex agglutination with enzyme immunoassay for detection of rotavirus in fecal specimens.

Human rotaviruses are the most important etiologic agents of acquired diarrhea in infants and young children worldwide. Early diagnosis is essentialfor effective patient treatment. The latex agglutination (LA) assays for rotavirus diagnosis are rapid, inexpensive, and the most widely used to screen specimens. The performance of the LA Rotagen (Biokit S.A., Barcelona, Spain) was evaluated for rotavirus detection infecal samples of outpatients with acute gastroenteritis. This assay was compared with the enzyme immunoassay (EIA) EIARA (Bio-Manguinhos, Rio de Janeiro, Brazil). From January to October 2000, 285 fecal specimens were analyzed. Forty-four samples (15.4%) were reactive, 214 (75.4%) were nonreactive, and 27 (9.5%) were indeterminate by LA. All LA-positive samples were positive by EIA, and 2 LA-negative samples were positive by EIA. Of specimens indeterminate by LA, 67% were positive by EIA. The sensitivity, specificity, and accuracy of LA were 69%, 100%, and 93%, respectively. These results indicate that assay is as sensitive and specific as the EIA, and it could be applied on a large scale for screening stool specimens in suspected rotavirus diarrhea. However, the indeterminate results must be confirmed by other methods, such as EIA.

Neurocognitive Impairment in HIV-1 Clade C versus B Infected Individuals in Southern Brazil

HIV-1 clade C isolates show reduced Tat protein chemoattractant activity compared with clade B. This might influence neuropathogenesis by altering trafficking of monocytes into the CNS. A previous study suggested low rates of HIV-associated dementia in clade C-infected individuals. The present study evaluated neurocognitive impairment rates in clade B- and C-infected individuals from the same local population. HIV+ and HIV− participants were recruited from the same geographic region in Southern Brazil. We evaluated neuropsychological (NP) impairment using a screening instrument (the International HIV Dementia Scale (IHDS)), as well as a Brazilian Portuguese adaptation of a comprehensive battery that has demonstrated sensitivity to HIV-associated neurocognitive disorders (HAND) internationally. NP performance in controls was used to generate T scores and impairment ratings by the global deficit score (GDS) method. Clade assignments were ascertained by sequencing pol and env. Blood and cerebrospinal fluid were collected from all HIV+ participants. HIV+ and HIV− participants were comparable on demographic characteristics. HIV+ participants overall were more likely to be impaired than HIV− by the IHDS and the GDS. Clade B- and C-infected individuals were demographically similar and did not differ significantly in rates of impairment. The prevalence of pleocytosis, a marker of intrathecal cellular chemotaxis, also did not differ between clade B and C infections. Clade B and C HIV-infected individuals from the same geographic region, when ascertained using comparable methods, did not differ in their rates of neurocognitive impairment, and there was no evidence of differences in CNS chemotaxis.

Phylogenetic characterization of hantaviruses from wild rodents and hantavirus pulmonary syndrome cases in the state of Paraná (southern Brazil).

Over 1,100 cases of hantavirus pulmonary syndrome (HPS) have occurred in Brazil since 1993, but little is known about Brazilian hantaviruses, and many of their rodent hosts remain unknown. The Araucaria hantavirus (ARAUV) was described recently from HPS patients from Paraná, in southern Brazil, but its host could not be identified. In this study, rodents were captured from regions with high HPS prevalence to address this issue. ARAUV RNA was detected in three distantly related rodent species: Oligoryzomys nigripes, Oxymycterus judex and Akodon montensis. Furthermore, a specimen of A. montensis was infected with a Jaborá-like virus, implying that A. montensis can be infected by at least two different hantaviruses. The presence of the same hantavirus strain in three different rodent species and the co-circulation of two different strains in the same rodent species highlight the potential for genomic reassortment, which could have an impact on hantavirus transmission dynamics in nature and on human epidemiology.

Production and characterization of monoclonal antibodies against the recombinant nucleoprotein of Araucaria hantavirus

Hantaviruses are rodent-borne RNA viruses that cause hemorrhagic fever with renal syndrome (HFRS) or hantavirus pulmonary syndrome (HPS). From the first detection of infection in Brazil in 1993 until 2009, 1161 cases of HPS have been reported, with mortality rates of around approximately 40%. Currently, due to the absence of a vaccine or specific antiviral therapy, the only way to reduce mortality by hantavirus infection is a fast and precise diagnosis that allows for supportive clinical health care. To improve the detection of hantavirus infection, we developed monoclonal antibodies (Mabs) against the nucleoprotein (rNDelta85) of the Araucaria hantavirus strain (ARAUV). The specificity of generated Mabs for rNDelta85 was demonstrated by western blot, indirect immunofluorescence and immunohistochemistry. These are the first monoclonal antibodies to be produced and characterized against the South American hantavirus strain, and may be of special interest in the development of diagnostic assays and epidemiological studies.

Evidence of circulation of Laguna Negra-like hantavirus in the Central West of Brazil: Case report

BACKGROUND Hantavirus pulmonary syndrome has been reported with increasing frequency in some Brazilian regions, but information about viral genetic identification is still limited. Recently, the state of Mato Grosso, in the Legal Amazon of Brazil, experienced a growing number of hantavirus pulmonary syndrome (HPS) cases but the genetic characterization of the causative hantavirus is still missing. OBJECTIVES Our goal was to identify the hantavirus strain involved in a fatal HPS case in the Central region of Brazil. STUDY DESIGN Nested RT-PCR was conducted on blood clot samples from an HPS patient from Mato Grosso. PCR-positive samples were sequenced, and the resulting sequences were compared with reference samples. Viral antigens were detected by immunohistological analyses in lung and liver tissues. RESULTS Analyses of the viral RNA isolated from the patient identified a Laguna Negra (LN)-like virus as the causative agent and histological analysis of lung sections were compatible with the genetic characterization. CONCLUSIONS This is the first report of circulation and human infection by a Laguna Negra-like hantavirus in Brazil.

Viral acute gastroenteritis: clinical and epidemiological features of co-infected patients

BACKGROUND Acute gastroenteritis (AGE) is a common disorder that affects children worldwide. It is usually caused by viral agents, including rotavirus, enteric adenovirus, norovirus, and astrovirus groups. Currently, there are few reports about co-infection among these viruses, mainly in Brazil. METHODS This is a retrospective study in which 84 rotavirus-positive samples from hospitalized patients at a teaching hospital in Southern Brazil, collected in the 2001-2010 period, were analyzed by polymerase chain reaction (PCR) and reverse transcription-polymerase chain reaction (RT-PCR), for the investigation of enteric adenovirus, astrovirus, and norovirus. RESULTS In total, 12 of the 84 (14%) samples were positive to enteric adenovirus or norovirus. Clinical, laboratory, and demographic data showed statistically significant differences between mono and co-infected patients, including age and depletion rate. CONCLUSIONS These findings highlight the need for implementation of other enteric virus detection assays in clinical diagnosis for a complete laboratory investigation of hospitalized pediatric patients with AGE, in order to understand the impact of these pathogens on disease severity, spread within hospital, and consequently, prevent the dissemination of nosocomial infections.

Laboratory Diagnosis, Epidemiology, and Clinical Outcomes of Pandemic Influenza A and Community Respiratory Viral Infections in Southern Brazil

ABSTRACT Community respiratory viruses (CRVs) are commonly associated with seasonal infections. They have been associated with higher morbidity and mortality among children, elderly individuals, and immunosuppressed patients. In April 2009, the circulation of a new influenza A virus (FLUA H1N1v) was responsible for the first influenza pandemic of this century. We report the clinical and epidemiological profiles of inpatients infected with CRVs or with FLUA H1N1v at a tertiary care hospital in southern Brazil. In addition, we used these profiles to evaluate survivor and nonsurvivor patients infected with FLUA H1N1v. Multiplex reverse transcription-PCR (RT-PCR) and real time RT-PCR were used to detect viruses in inpatients with respiratory infections. Record data from all patients were reviewed. A total of 171 patients were examined over a period of 16 weeks. Of these, 39% were positive for FLUA H1N1v, 36% were positive for CRVs, and 25% were negative. For the FLUA H1N1v- and CRV-infected patients, epidemiological data regarding median age (30 and 1.5 years), myalgia (44% and 13%), need for mechanical ventilation (44% and 9%), and mortality (35% and 9%) were statistically different. In a multivariate analysis comparing survivor and nonsurvivor patients infected with influenza A virus H1N1, median age and creatine phosphokinase levels were significantly associated with a severe outcome. Seasonal respiratory infections are a continuing concern. Our results highlight the importance of studies on the prevalence and severity of these infections and that investments in programs of clinical and laboratory monitoring are essential to detect the appearance of new infective agents.

Quantitation of cerebrospinal fluid lactic acid in infectious and non-infectious neurological diseases

Abstract Background: The differential diagnosis between bacterial and viral meningitis is not easy in some cases. Cerebrospinal fluid (CSF) analysis is essential for establishing this diagnosis. The objectives were to quantitate lactic acid (LA) concentrations in bacterial and viral meningitis, and other central nervous system (CNS) diseases in order to evaluate the diagnostic utility of CSF LA for discriminating bacterial from viral meningitis. Methods: CSF LA was measured in 139 CSF samples from seven groups: viral meningitis with classic CSF; suspicion of viral meningitis with neutrophils in CSF; bacterial meningitis; non-infectious neurological diseases; chronic meningitis; traumatic lumbar puncture (LP) and normal CSF. Results: CSF LA was higher in bacterial meningitis 8.7+5.4 mmol/L compared with viral meningitis (1.9+0.6) and the other groups (p<0.0001). CSF LA in the groups with viral meningitis was not different compared to groups with non-infectious CNS diseases and chronic meningitis. The ability of CSF LA to discriminate bacterial from viral meningitis showed a sensitivity of 80% and specificity of 97%, positive predictive value (PPV) of 94%, and negative predictive value (NPV) of 89%. Conclusions: CSF LA is a powerful test to discriminate bacterial from viral meningitis with high sensitivity, specificity and predictive values. CSF LA can help in the cases with diagnostic uncertainty. Clin Chem Lab Med 2009;47:755–61.