Eduardo da Silva Carvalho

Nosocomial infection in a pediatric intensive care unit in a developing country

OBJECTIVE Determine the rate and outcome of nosocomial infection (NI) in pediatric intensive care unit patients in a developing country. DESIGN Prospective cohort study using the Centers for Disease Control and Prevention definitions to diagnose nosocomial infection and NNISS (National Nosocomial Infection Surveillance System) methodology. SETTING São Paulo Hospital - Universidade Federal de São Paulo - Brazil, a 700-bed teaching hospital with an 8-bed pediatric intensive care unit. PARTICIPANTS All 515 children consecutively admitted to the pediatric intensive care unit from April 1996 to October 1997. RESULTS The NI incidence was 18.3% and the mean infection rate per 1,000 patient days was 46.1; the ventilator-associated pneumonia rate was 18.7 per 1,000 ventilator days; the central line-associated bloodstream infection rate was 10.2 per 1,000 central line days; and the urinary tract catheter-associated infection rate was 1.8 per 1,000 catheter days. Pneumonia was the most common NI (31.6%), followed by bloodstream infections (17.3%), and surgical site infection (17.3%). Gram-negative bacterias were the most common pathogens identified in the NIs (54.8%), followed by Gram-positive bacterias (23.8%), and yeasts. CONCLUSION Pneumonia was the most common type of NI. A high incidence of ventilator-associated pneumonia and central line-associated bloodstream infections was found, whereas the urinary tract catheter-associated infection rate was low. Gram-negative bacterias were the most common etiologic agents identified in the unit, and yeasts were frequently found. Pediatric patients have characteristics of their own, with major differences when compared to the adult population.

Clinical presentation and follow up of children with congenital toxoplasmosis in Brazil

We evaluated the clinical presentation and determined the ocular and neurologic sequelae in children with congenital toxoplasmosis in Brazil, taking into consideration the shortage of national publications on this disease. Follow-up evaluations were made of 43 children with congenital toxoplasmosis referred to Santa Casa de São Paulo, during a period of at least five years. Selection of the cases was based in clinical and laboratory criteria. A clear predominance of children with subclinical presentation of the disease at birth (88%) was found. Of the 43 children, 22 (51%) developed neurological manifestations. Using skull radiography, we detected neuroradiologic alterations in seven children (16%) and with tomography in 33 children (77%). Neurological sequelae were identified in 15 children (54%) in the group with cerebral calcifications and in 7 (47%) in the group without cerebral calcifications. We observed chorioretinitis in 95% of the cases. Reactivation of cicatricial lesions and the emergence of new ocular lesions were observed in five cases. The most frequent neurological manifestation was a delay in neuropsychomotor development. Most remarkable was the finding that cerebral calcifications were not associated with a higher incidence of neurological sequelae among the children. Chorioretinitis was the main ocular sequel of the infection, found in nearly all children; it can manifest years from birth, even in children submitted to specific therapy druing the first year of life, highlighting the importance of a follow-up of these children.

Maternal and infant antibody response to meningococcal vaccination in pregnancy.

The antigenic capacity of a mixed vaccine prepared with polysaccharides of meningococcus groups A and C, the placental transfer of antibodies, and the persistence of positive titres in the infant were evaluated in 21 pregnant women and their offspring during an epidemic of meningitis in São Paulo, Brazil; and antibody response was assessed in 29 infants vaccinated at less than 6 months of age. Antibodies were detected by passive haemagglutination; the high titres found and the high frequency of positive results are thought to be due to the use of a more sensitive technique. Increased antibody titres were found in most women, and there was evidence for passive transfer to the newborn, especially with regard to antibody type C. However, passive transfer was irregular, and the presence of antibodies in the mother did not guarantee their presence in the child. Passive transfer lasted for only 2-5 months. Vaccination in children under 6 months of age had poor results; only 1 child seroconverted.

Uso de diagramas de controle na vigilância epidemiológica das infecções hospitalares

OBJECTIVE To monitor occurrence trends and identify clusters of nosocomial infection (NI) using statistical process control (SPC) charts. METHODS Between January 1998 and December 2000 nosocomial infection occurrence was evaluated in a cohort of 460 patients admitted to the Pediatric Intensive Care Unit of a university hospital, according to the concepts and criteria proposed by the National Nosocomial Infection Surveillance System of the Centers for Disease Control, in the United States. Graphs were plotted using Poisson statistical distribution, including four horizontal lines: center line (CL), upper warning limit (UWL) and upper control limit (UCL). The CL was the arithmetic mean NI rate calculated for the studied period; UWL and UCL were drawn at 2 and 3 standard deviations above average NI rates, respectively. Clusters were identified when NI rates remained above UCL. RESULTS Mean NI incidence was 20 per 1,000 patient days. One urinary tract infection cluster was identified in July 2000, with an infection rate of 63 per 1,000 patient days, exceeding UCL and characterizing a period of epidemic. CONCLUSIONS The use of SPC charts for controlling endemic levels of NI, through both global and site-specific evaluation, allowed for the identification of uncommon variations in NI rates, such as outbreaks and epidemics, and for their distinction from the natural variations observed in NI occurrence rates, without the need for calculations and hypothesis testing.

Colonização e resistência antimicrobiana de streptococcus pneumoniae isolado em nasofaringe de crinças com rinofaringite aguda

OBJETIVO: avaliar a prevalencia e os fatores de risco para a colonizacao nasofaringea e determinar o padrao de suscetibilidade a penicilina de cepas isoladas da nasofaringe de criancas com rinofaringite aguda. METODOLOGIA: No periodo de 16/6/97 a 20/5/98 foram coletados 400 Swabs da nasofaringe de criancas com idade entre tres meses e cinco anos que apresentavam quadro clinico de rinofaringite aguda. A identificacao do S. pneumoniae foi realizada atraves do teste de optoquina e solubilidade em bile. Todas as cepas foram triadas atraves do disco de oxacilina 1mg, sendo avaliada, posteriormente, a concentracao inibitoria minima para penicilina pelo metodo do E-teste. RESULTADOS: A prevalencia da colonizacao nasofaringea pelo S. pneumoniae foi de 35%. A analise dos fatores de risco associados a colonizacao nasofaringea indicou que as criancas que eram institucionalizadas e que tinham irmaos menores de cinco anos apresentaram uma taxa maior de colonizacao. A prevalencia de cepas nao suscetiveis a penicilina foi de 16%. Todas as cepas apresentaram resistencia intermediaria (0,1mcg/ ml £ CIM £ 1,0 mcg/ ml ). Das 19 cepas com resistencia a penicilina, 7 tinham resistencia intermediaria (37%), e duas (11%) resistencia elevada ao cotrimoxazol. Nao foi observada resistencia a ceftriaxona, amoxicilina, claritromicina ou cloranfenicol. CONCLUSOES: Concluimos que a prevalencia da colonizacao nasofaringea pelo pneumococo, em criancas menores de cinco anos com quadro de rinofaringite aguda, foi de 34,8%; as que eram institucionalizadas e tinham irmaos menores apresentaram uma maior taxa de colonizacao. A resistencia a penicilina ocorreu em 15,6% dos isolados, nao sendo detectada nenhuma cepa com resistencia elevada. A taxa de resistencia bacteriana encontrada foi bastante proxima a encontrada em estudo de infeccoes invasivas. Este fato sugere que os isolados de pneumococo da nasofaringe de criancas com infeccao respiratoria alta podem ser usados na vigilância da resistencia antimicrobiana numa determinada comunidade.

Seroconversion of a trivalent measles, mumps, and rubella vaccine in children aged 9 and 15 months

The serological response to MMR vaccine was evaluated in 109 9-month-old infants having no history of measles vaccination, and in 98 15-month-old children who had received monocomponent measles immunisation at 9 months. The combined vaccine contained Schwarz, Urabe Am9, and Wistar RA 27/3 live attenuated virus strains. Preimmunisation antibody levels were extremely low for the 9-month-old children, indicating that maternally-transmitted antibodies do not persist at this age. In the case of mumps, preimmunisation antibody levels were significantly higher in the 15-month-old than in the 9-month-old group. A difference between groups in terms of postimmunisation antibody titres was observed only for rubella, with titres being significantly higher in the older group. Seroconversion rates were high in both groups and no serious events attributable to vaccination were observed. The MMR vaccine can thus be administered to children as young as 9 months of age. Evidence for the efficacy of a two-dose schedule, i.e. at 9 and 15 months, is presented.

Pediatric Risk of mortality and hospital infection

We studied the association of Pediatric Risk of Mortality scores with nosocomial infections among 341 critically ill patients admitted to a pediatric intensive care unit between June 1998 and December 2000. Through stepwise logistic regression analysis, the best predictors for nosocomial infections were device utilization ratio, antimicrobial therapy, and length of stay.

Associated or combined vaccination of Brazilian infants with a conjugate Haemophilus influenzae type b (Hib) vaccine, a diphtheria-tetanus-whole-cell pertussis vaccine and IPV or OPV elicits protective levels of antibodies against Hib.

This study investigated the immunogenicity and safety of including a Haemophilus influenzae type b vaccine (polyribosylribitol phosphate conjugated to tetanus toxoid, PRP-T) in three different vaccination schemes: (1) PRP-T reconstituted with a combined diphtheria-tetanus-pertussis-inactivated poliovirus vaccine (DTP-IPV//PRP-T); (2) PRP-T reconstituted with DTP and administered concomitantly with an oral poliovirus vaccine (DTP//PRP-T+OPV); and (3) PRP-T administered concomitantly with DTP at a different injection site and OPV (DTP+PRP-T+OPV). Vaccines were given at 2, 4, and 6 months of age. A total of 252 infants were enrolled, and randomly assigned to one of the three vaccination groups (84 infants in each group); 241 infants were followed until the end of the study. Antibody production against PRP, diphtheria, tetanus and pertussis antigens was satisfactory for each vaccination scheme used. A good response to Hib vaccine was elicited in each group, and 3 months after the third vaccine dose, at least 97% of children in each group had levels of PRP antibody considered to be seroprotective (>0.15 microg/ml), and over 90% of children in each group had levels over 1. 0 microg/ml. The solicited local and systemic adverse events following vaccination were mild in all groups and resolved within 4 days without medical intervention. With the exception of fever, which was more common after the second dose in children who received DTP-IPV//PRP-T, local and systemic reactions did not differ between the vaccination groups. Due to the practical advantages of combined vaccines, their use in routine immunization programs in developing countries is highly desirable. Our results show that Hib conjugate vaccine can be included in routine immunization programs that include either OPV or IPV with satisfactory immunogenicity and safety profiles. This flexible approach should facilitate the inclusion of the Hib conjugate vaccine in routine immunization programs on a world-wide scale.

Viridans streptococci causing community acquired pneumonia

In children under 5 years of age, presenting to the paediatric emergency room with clinical and radiological findings of pneumonia, viridans streptococci were isolated in 10/33 positive haemocultures as the only microorganism. Viridans streptococci should therefore not be ruled out as a cause of pneumonia.

Coxsackie B2 virus fatal meningoencephalitis in a student

OBJECTIVE: To present the case of a girl who was previously healthy but had fatal evolution due to Coxsackie B2 viral meningoencephalitis.METHODS: The authors describe the case of a female child with fatal meningoencephalitis caused by Coxsackie B2 virus and present a review of the literature (Medline and Lilacs).RESULTS: The girl was eight years old when she presented meningoencephalitis with bad evolution, leading to death on the 32nd day of internation. The exams showed positive serologic reaction to Coxsackie B2. The virus taken from two stool samples was isolated. The CRF exam showed an increase four times higher on Coxsackie B2 titulation.CONCLUSION: The death of healthy patients with enteroviral encephalitis, as described here, is rarely dealt with in the medical literature, perhaps because of lack of clinic suspicion. This case tries to drive attention to the importance of an early etiologic diagnosis in the meningoencephalities and the search for specific etiological treatment.