Acute respiratory viral infections in children in Rio de Janeiro and Teresópolis, Brazil

The frequency of viral pathogens causing respiratory infections in children in the cities of Rio de Janeiro and Teresópolis was investigated. Nasal swabs from children with acute respiratory illnesses were collected between March 2006 and October 2007. Specimens were tested for viral detection by conventional (RT)-PCR and/or real time PCR. Of the 205 nasal swabs tested, 64 (31.2%) were positive for at least one of the viral pathogens. Single infections were detected in 56 samples, 50 of those were caused by RNA viruses: 33 samples tested positive for rhinovirus, five for influenza A, five for metapneumovirus, four for coronavirus and, three for respiratory syncytial virus. For the DNA viruses, five samples were positive for bocavirus and one for adenovirus. Co-infections with these viruses were detected in eight samples. Our data demonstrate a high frequency of viral respiratory infections, emphasizing the need for a more accurate diagnosis particularly for the emerging respiratory viruses. The fact that the emerging respiratory viruses were present in 9.2% of the tested samples suggests that these viruses could be important respiratory pathogens in the country.

High occurrence of giardiasis in children living on a 'landless farm workers' settlement in Araras, São Paulo, Brazil

Enteric parasitosis remains an important public health problem in many areas around the world including in Brazil, and it is frequently associated with poverty and lack of sanitation facilities. Research carried out over the course of a year revealed that 96.6% (28/29) of children randomly selected from a 'landless farm workers' settlement in Araras, São Paulo, aged 4 - 15 years, presented Giardia intestinalis cysts. After referral to the neighborhood Health Office, all the children received tinidazole, given as a single dose of 50 mg/kg and 12 months later, new fecal samples were collected and analyzed. Despite the low adherence to the study, a high percentage (64.3% - 9/14) of the children remained positive for the parasite. This study showed a high positivity of giardiasis in child residents of the settlement, even after treatment; adults were not sensitized to the study and did not collected and/or deliver children fecal samples. The precarious living conditions are consistent with a high susceptibility to parasitic diseases, suggesting that the treatment of the infected individuals without identifying and eradicating the means of contamination is simply a palliative measure.

Toxocariasis in children attending a Public Health Service Pneumology Unit in Paraná State, Brazil

The enzyme-linked immunosorbent assay (ELISA) is the most widely used tool to detect anti-Toxocara IgG antibodies for both serodiagnostic and seroepidemiological surveys on human toxocariasis. In the last eight years a high prevalence of toxocariasis (32.2-56.0%) has been reported in children attending public health units from municipalities in the state of Paraná, Brazil. Therefore, the aim of this work was to compare the frequency found among the general child population with that of children attending a public pneumology service in Maringá, Paraná, Brazil and describe the laboratorial, clinical and epidemiological findings. The research was conducted at the Consórcio Público Intermunicipal de Saúde do Setentrião Paranaense (CISAMUSEP) from July 2009 to July 2010 among children aged between one and 15 years. From a total of 167 children studied, only 4.2% (7/167) tested positive for anti-Toxocara spp. IgG antibodies and presented mild eosinophilia (2/7), increased serum IgE levels (6/7) and a positive allergy test for mites (5/7). The presence of pets (dogs or cats) at home did not correlate with the seroprevalence. In conclusion, cases of toxocariasis involving the respiratory tract are rare in children attending a public health pneumology unit in the northwestern region of Paraná State, despite the high prevalence of this type of toxocariasis among the infantile population attending Basic Health Units in the same geographical area.

ESTABLISHING THE REFERENCE RANGE FOR T LYMPHOCYTES SUBPOPULATIONS IN ADULTS AND CHILDREN FROM BRAZIL

SUMMARY In Brazil, the existing reference values for T-lymphocytes subsets are based on data originated in other countries. There is no local information on normal variation for these parameters in Brazilian adults and children. We evaluated the normal variation found in blood donors from five large Brazilian cities, in different regions, and in children living in Salvador, and Rio de Janeiro. All samples were processed by flow cytometry. The results were analyzed according to region, gender, and lifestyle of blood donors. A total of 641 adults (63% males), and 280 children (58% males) were involved in the study. The absolute CD3+, and CD4+ cells count were significantly higher for females (adults and children). Higher CD4+ cell count in adults was associated with smoking, while higher CD8+ count was found among female children. Higher counts, for all T-cells subsets, were detected in blood donors from southeast / south regions while those living in the northern region had the lowest values. Individuals from midwestern and northeastern regions had an intermediate count for all these cells subsets. However, these differences did not reach statistical significance. In Brazil, gender and smoking, were the main determinants of differences in T-lymphocytes reference values.

NEUROCYSTICERCOSIS IN CHILDREN PRESENTING WITH AFEBRILE SEIZURE: CLINICAL PROFILE, IMAGING AND SERODIAGNOSIS

Neurocysticercosis (NCC) is one of the major causes of childhood seizures in developing countries including India and Latin America. In this study neurological pediatric cases presenting with afebrile seizures were screened for anti-Cysticercus antibodies (IgG) in their sera in order to estimate the possible burden of cysticercal etiology. The study included a total of 61 pediatric afebrile seizure subjects (aged one to 15 years old); there was a male predominance. All the sera were tested using a pre-evaluated commercially procured IgG-ELISA kit (UB-Magiwell Cysticercosis Kit ™). Anti-Cysticercus antibody in serum was positive in 23 of 61 (37.7%) cases. The majority of cases with a positive ELISA test presented with generalized seizure (52.17%), followed by complex partial seizure (26.08%), and simple partial seizure (21.73%). Headaches were the major complaint (73.91%). Other presentations were vomiting (47.82%), pallor (34.78%), altered sensorium (26.08%), and muscle weakness (13.04%). There was one hemiparesis case diagnosed to be NCC. In this study one child without any significant findings on imaging was also found to be positive by serology. There was a statistically significant association found between the cases with multiple lesions on the brain and the ELISA-positivity (p = 0.017). Overall positivity of the ELISA showed a potential cysticercal etiology. Hence, neurocysticercosis should be suspected in every child presenting with afebrile seizure especially with a radio-imaging supportive diagnosis in tropical developing countries or areas endemic for taeniasis/cysticercosis.

FUNGEMIA CAUSED BY Candida SPECIES IN A CHILDREN'S PUBLIC HOSPITAL IN THE CITY OF SÃO PAULO, BRAZIL: STUDY IN THE PERIOD 2007-2010

Candidemia remains a major cause of morbidity and mortality in the health care environment. The epidemiology of Candida infection is changing, mainly in relation to the number of episodes caused by species C. non-albicans. The overall objective of this study was to evaluate the frequency of yeasts of the genus Candida, in a four-year period, isolated from blood of pediatric patients hospitalized in a public hospital of the city of São Paulo, Brazil. In this period, yeasts from blood of 104 patients were isolated and, the identified species of Candida by phenotypic and genotypic methods were: C. albicans (39/104), C. tropicalis (25/104), C. parapsilosis (23/104), Pichia anomala (6/104), C. guilliermondii (5/104), C. krusei (3/104), C. glabrata (2/104) and C. pararugosa (1/104). During the period of the study, a higher frequency of isolates of C. non-albicans (63.55%) (p = 0.0286) was verified. In this study we verified the increase of the non-albicans species throughout the years (mainly in 2009 and 2010). Thus, considering the peculiarities presented by Candida species, a correct identification of species is recommended to lead to a faster diagnosis and an efficient treatment.

SEROLOGICAL MARKERS OF VIRAL, SYPHILITIC AND TOXOPLASMIC INFECTION IN CHILDREN AND TEENAGERS WITH NEPHROTIC SYNDROME: CASE SERIES FROM MATO GROSSO STATE, BRAZIL

Some infections can be the cause of secondary nephrotic syndrome. The aim of this study was to describe the experience of a Renal Disease Reference Clinic from Central Brazil, in which serological markers of some infectious agents are systematically screened in children with nephrotic syndrome. Data were obtained from the assessment of medical files of all children under fifteen years of age, who matched nephrotic syndrome criteria. Subjects were tested for IgG and IgM antibodies against T. gondii and cytomegalovirus; antibodies against Herpes simplex, hepatitis C virus and HIV; and surface antigen (HBsAg) of hepatitis B virus. The VDRL test was also performed. 169 cases were studied. The median age on the first visit was 44 months and 103 (60.9%) patients were male. Anti-CMV IgG and IgM were found in 70.4% and 4.1%, respectively. IgG and IgM against Toxoplasma gondii were present in 32.5% and 5.3%, respectively. Two patients were positive for HBsAg, but none showed markers for HIV, hepatitis C, or Treponema pallidum. IgG and IgM against herpes simplex virus were performed on 54 patients, of which 48.1% and 22.2% were positive. IgM antibodies in some children with clinical signs of recent infection suggest that these diseases may play a role in the genesis of nephrotic syndrome.

LACK OF ASSOCIATION BETWEEN HERPESVIRUS DETECTION IN SALIVA AND GINGIVITIS IN HIV‑INFECTED CHILDREN

The aims of this study were to compare the detection of human herpesviruses (HHVs) in the saliva of HIV-infected and healthy control children, and to evaluate associations between viral infection and gingivitis and immunodeficiency. Saliva samples were collected from 48 HIV-infected and 48 healthy control children. Clinical and laboratory data were collected during dental visits and from medical records. A trained dentist determined gingival indices and extension of gingivitis. Saliva samples were tested for herpes simplex virus types 1 and 2 (HSV-1 and HSV-2), varicella zoster virus (VZV), Epstein-Barr virus (EBV), and cytomegalovirus (CMV) by nested polymerase chain reaction assays. Thirty-five HIV-infected and 16 control children had gingivitis. Seventeen (35.4%) HIV-infected children and 13 (27%) control children were positive for HHVs. CMV was the most commonly detected HHV in both groups (HIV-infected, 25%; control, 12.5%), followed by HSV-1 (6.2% in both groups) and HSV-2 (HIV-infected, 4.2%; control, 8.3%). The presence of HHVs in saliva was not associated with the presence of gingivitis in HIV-1-infected children (p = 0.104) or healthy control children (p = 0.251), or with immunosuppression in HIV-infected individuals (p = 0.447). Gingivitis was correlated with HIV infection (p = 0.0001). These results suggest that asymptomatic salivary detection of HHVs is common in HIV-infected and healthy children, and that it is not associated with gingivitis.

Methacholine Dose-Response Slopes from Maximal Bronchial Challenge Tests in Asthmatic Children: Methodological Aspects

To determine whether the slope of a maximal bronchial challenge test (in which FEV1 falls by over 50%) could be extrapolated from a standard bronchial challenge test (in which FEV1 falls up to 20%), 14 asthmatic children performed a single maximal bronchial challenge test with methacholin(dose range: 0.097–30.08 umol) by the dosimeter method. Maximal dose-response curves were included according to the following criteria: (1) at least one more dose beyond a FEV1 ù 20%; and (2) a MFEV1 ù 50%. PD20 FEV1 was calculated, and the slopes of the early part of the dose-response curve (standard dose-response slopes) and of the entire curve (maximal dose-response slopes) were calculated by two methods: the two-point slope (DRR) and the least squares method (LSS) in % FEV1 × umol−1. Maximal dose-response slopes were compared with the corresponding standard dose-response slopes by a paired Student’s t test after logarithmic transformation of the data; the goodness of fit of the LSS was also determined. Maximal dose-response slopes were significantly different (p < 0.0001) from those calculated on the early part of the curve: DRR20% (91.2 ± 2.7 FEV1% z umol−1)was 2.88 times higher than DRR50% (31.6 ± 3.4 DFEV1% z umol−1), and the LSS20% (89.1 ± 2.8% FEV1 z umol−1) was 3.10 times higher than LSS 50% (28.8 ± 1.5%FEV1 z umol−1). The goodness of fit of LSS 50% was significant in all cases, whereas LSS 20% failed to be significant in one. These results suggest that maximal dose-response slopes cannot be predicted from the data of standard bronchial challenge tests.

Development Process and Cognitive Testing of CARATkids - Control of Allergic Rhinitis and Asthma Test for Children

Background: Allergic rhinitis and asthma (ARA) are chronic inflammatory diseases of the airways that often coexist in children. The only tool to assess the ARA control, the Control of Allergic Rhinitis and Asthma Test (CARAT) is to be used by adults. We aimed to develop the Pediatric version of Control of Allergic Rhinitis and Asthma Test (CARATkids) and to test its comprehensibility in children with 4 to 12 years of age. Methods: The questionnaire development included a literature review of pediatric questionnaires on asthma and/or rhinitis control and two consensus meetings of a multidisciplinary group. Cognitive testing was carried out in a cross-sectional qualitative study using cognitive interviews. Results: Four questionnaires to assess asthma and none to assess rhinitis control in children were identified. The multidisciplinary group produced a questionnaire version for children with 17 questions with illustrations and dichotomous (yes/no) response format. The version for caregivers had 4-points and dichotomous scales. Twenty-nine children, 4 to 12 years old, and their caregivers were interviewed. Only children over 6 years old could adequately answer the questionnaire. A few words/expressions were not fully understood by children of 6 to 8 years old. The drawings illustrating the questions were considered helpful by children and caregivers. Caregivers considered the questionnaire complete and clear and preferred dichotomous over the 4-points scales. The proportion of agreement between children and their caregivers was 61%. The words/expressions that were difficult to understand were amended. Conclusion: CARATkids, the first questionnaire to assess a child’s asthma and rhinitis control was developed and its content validity was assured. Cognitive testing showed that CARATKids is well-understood by children 6 to 12 years old. The questionnaire’s measurement properties can now be assessed in a validation study.

Neuropsychological Abnormalities in Children with the Panayiotopoulos Syndrome Point to Parietal Lobe Dysfunction

Panayiotopoulos syndrome (PS) is a common epilepsy syndrome associated with rare clinical seizures and unknown localization of the epileptogenic area. Despite findings of normal development in patientswith PS, recent neuropsychological studies point to subtle and diverse cognitive impairments. No well-outlined hypothesis about the localization of the brain dysfunction responsible for these impairments has been proposed.We further explored the cognitive dysfunctions in PS andmade inferences on the most likely anatomical localization of brain impairment. A group of 19 patients (aged 6–12) with PS was rated according to spike activity and lateralization. The patients were submitted to a neuropsychological evaluation to assess general intelligence, memory, language, visual–perceptual abilities, attention, and executive functions. Using 35-channel scalp EEG recordings, the N170 face-evoked event-related potential (ERP)was obtained to assess the functional integrity of the ventral pathway. All patientswith PS showed normal IQ but subtle and consistent neurocognitive impairments. Namely, we found abnormalities in the copy task of the Rey–Osterrieth Complex Figure and in theNarrative Memory Test. There was no correlation between neuropsychological impairments with spike activity and hemispheric spike lateralization. The N170 ERP was normal in all patients except for one. Our neuropsychological findings demonstrate impairments in visual–perceptual abilities and in semantic processing. These findings, paired with the absence of occipital lobe dysfunction in all neuropsychological studies of PS performed to this date, support the existence of parietal lobe dysfunction.

Development of The Viking Speech Scale to Classify the Speech of Children with Cerebral Palsy

Surveillance registers monitor the prevalence of cerebral palsy and the severity of resulting impairments across time and place. The motor disorders of cerebral palsy can affect children’s speech production and limit their intelligibility. We describe the development of a scale to classify children’s speech performance for use in cerebral palsy surveillance registers, and its reliability across raters and across time. Speech and language therapists, other healthcare professionals and parents classified the speech of 139 children with cerebral palsy (85 boys, 54 girls; mean age 6.03 years, SD 1.09) from observation and previous knowledge of the children. Another group of health professionals rated children’s speech from information in their medical notes. With the exception of parents, raters reclassified children’s speech at least four weeks after their initial classification. Raters were asked to rate how easy the scale was to use and how well the scale described the child’s speech production using Likert scales. Inter-rater reliability was moderate to substantial (k > .58 for all comparisons). Test–retest reliability was substantial to almost perfect for all groups (k > .68). Over 74% of raters found the scale easy or very easy to use; 66% of parents and over 70% of health care professionals judged the scale to describe children’s speech well or very well. We conclude that the Viking Speech Scale is a reliable tool to describe the speech performance of children with cerebral palsy, which can be applied through direct observation of children or through case note review.

Epidemiological studies of Streptococcus pneumoniae carriage in the post-vaccination era among two risk groups: children and the elderly

Dissertation presented to obtain the Ph.D. degree in Biology/ Molecular Biology

HIGH PREVALENCE OF Blastocystis spp. INFECTION IN CHILDREN AND STAFF MEMBERS ATTENDING PUBLIC URBAN SCHOOLS IN SÃO PAULO STATE, BRAZIL

After a gastroenteritis outbreak of unknown etiology in the municipality ofSebastião da Grama, SãoPaulo, Brazil, we conducted a parasitological survey to establish the epidemiological profile of enteroparasitosis in children and staff members attending the public urban schools in operation in town. The cross-sectional study evaluated 172 children aged 11 months to 6 years old and 33 staff members aged 19 to 58 years old. Overall, 96 (55.81%) children and 20 (60.61%) staff members were mono-parasitized, while 58 (33.72%) children and 4 (12.12%) workers were poly-parasitized. Protozoa (88.37%; 72.73%) was more prevalent than helminthes (3.48%; 0%) in children and staff members respectively.Blastocystis spp. was the most prevalent parasite in children (86.63%) and staff members (66.67%). The age of 1 year old or less was found to be associated with increased prevalence of giardiasis [OR = 13.04; 95%CI 2.89-58.91; p = 0.00] and public garbage collection was identified as a protective factor against intestinal helminth infections [OR = 0.06; 95%CI 0.00-0.79; p = 0.03]. Although most of the children tested positive for Blastocystis spp. and also presented clinical signs/symptoms (62.2%), this association was not statistically significant [OR = 1.35; 95%CI 0.53-3.44; p = 0.51]. Intestinal parasites still represent a public health concern and this study underscores the importance of further investigations to better understand the pathogenic role ofBlastocystis spp.