Meri Bordignon Nogueira

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.

Evidence for the co-circulation of dengue virus type 3 genotypes III and V in the Northern region of Brazil during the 2002-2004 epidemics

The reintroduction of dengue virus type 3 (DENV-3) in Brazil in 2000 and its subsequent spread throughout the country was associated with genotype III viruses, the only DENV-3 genotype isolated in Brazil prior to 2002. We report here the co-circulation of two different DENV-3 genotypes in patients living in the Northern region of Brazil during the 2002-2004 epidemics. Complete genomic sequences of viral RNA were determined from these epidemics, and viruses belonging to genotypes V (Southeast Asia/South Pacific) and III were identified. This recent co-circulation of different DENV-3 genotypes in South America may have implications for pathological and epidemiological dynamics.

Acute gastroenteritis and enteric viruses in hospitalised children in southern Brazil: aetiology, seasonality and clinical outcomes.

Viral acute gastroenteritis (AG) is a significant cause of hospitalisation in children younger than five years. Group A rotavirus (RVA) is responsible for 30% of these cases. Following the introduction of RVA immunisation in Brazil in 2006, a decreased circulation of this virus has been observed. However, AG remains an important cause of hospitalisation of paediatric patients and only limited data are available regarding the role of other enteric viruses in these cases. We conducted a prospective study of paediatric patients hospitalised for AG. Stool samples were collected to investigate human adenovirus (HAdV), RVA, norovirus (NoV) and astrovirus (AstV). NoV typing was performed by nucleotide sequencing and phylogenetic analysis. From the 225 samples tested, 60 (26%) were positive for at least one viral agent. HAdV, NoV, RVA and AstV were detected in 16%, 8%, 6% and 0% of the samples, respectively. Mixed infections were found in nine patients: HAdV/RVA (5), HAdV/NoV (3) and HAdV/NoV/RVA (1). The frequency of fever and lymphocytosis was significantly higher in virus-infected patients. Phylogenetic analysis of NoV indicated that all of these viruses belonged to genotype GII.4. The significant frequency of these pathogens in patients with AG highlights the need to routinely implement laboratory investigations.

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.

Adenovirus respiratory infection: significant increase in diagnosis using PCR comparing with antigen detection and culture methods.

Adenovirus (AdV) respiratory infections are usually described as being associated with high mortality rates. Laboratory diagnosis is essential for the establishment of the appropriate therapy, and for guiding the implementation of preventive measures in order to prevent the spread of the infection. Aiming to analyze the sensitivity and specificity of the laboratorial diagnosis methods available, we compared antigen detection by indirect immunofluorescence assay (IF), and a specific nested polymerase chain reaction (PCR), to detect AdV in respiratory samples collected from patients admitted to hospital with acute respiratory disease. Positive samples were inoculated into a cell culture to confirm the results. We analyzed 381 samples from the nasopharyngeal aspirates collected during the year 2008; of these, 2.6% tested were positive for adenovirus through IF and 10% through PCR; positive isolation was obtained in 40% and 26% of these cases, respectively. Most infected patients were children under six months of age, and despite of the fact that a significant number of patients required intensive care, the mortality rate was low (5%). In conclusion, molecular methods were found to be useful for rapid diagnosis of adenovirus infections with higher sensitivity than antigen detection; their introduction permitted a significant increase in diagnoses of adenovirus infections.

Impact of human metapneumovirus infection on in and outpatients for the years 2006-2008 in Southern Brazil

The human metapneumovirus (hMPV), member of the Paramyxoviridae family, has been reported as an important agent involved with acute respiratory infections (ARIs). The aim of this study is to identify hMPV as the etiological agent of ARIs on in and outpatients in the city of Curitiba, Southern Brazil, and describe clinical data of hMPV subtyping. A retrospective study was performed in 1,572 respiratory samples over a period of three years. hMPV was detected by reverse transcription-polymerase chain reaction and subtyping was performed by nucleotide sequencing. hMPV was present in 61 (3.9%) samples and subtypes A1, A2a, B1 and B2 were detected. The incidence of hMPV was higher in outpatients (5.9%), whose mean age was 19.7 years (range 6 months-75 years old), than in inpatients (3%), whose mean age was 7.6 months (range 1 month-26 years old). The outpatients had upper respiratory tract infections with flu-like symptoms and all hospitalized children had lower respiratory tract infections. A pediatric patient died from complications associated with hMPV A2a infection. hMPV has been reported as a respiratory pathogen in all age groups. No correlation was observed between viral subtype and disease severity in the samples of this study.