Enfermedad neumocócica invasiva en niños menores de 5 años en la provincia de Málaga (1999-2001)

Abstract

Introduction The availability of the heptavalent pneumococcal conjugate vaccine has aroused great interest in the incidence and characteristics of invasive pneumococcal disease (IPD) in children in all countries, including Spain. Objectives To analyze the incidence of IPD and its variants in the province of Malaga (Spain) before the introduction of the heptavalent pneumococcal conjugate vaccine in Spain, and to compare the results with those found in other national and international series at that time. Material and methods A retrospective study of cases of IPD in children aged less than 5 years treated in hospitals in Malaga from 1999-2001 was performed. Data were obtained from databases of the Microbiology Services, Emergency Departments, Intensive Care Units, the Minimum Basic Data Set, pediatric hospitalisation registers and the Diseases of Mandatory Notification Register. Results Thirty-five patients were included. The most frequent clinical forms were occult bacteremia (12 cases, 34.2%), invasive pneumonia (12 cases, 34.2%) and meningitis (10 cases, 28.5%). There was one case of primary peritonitis in a nephrotic patient. The annual incidence rate for IPD in children under 2 years of age was 37 cases/100,000 children, higher than the 9.9 cases/100,000 children observed in the 24-59month age group. The annual incidence rates per 100,000 children in the 0-23month age group were 18.5 for occult bacteremia, 6.17 for invasive pneumonia and 12.33 for meningitis. The rate was higher for meningitis in children aged under 1 year with 15.7 cases/100,000. High prevalences of penicillinnon-susceptible (31.4%) and erythromycin- resistant (34%) strains were observed. Ten strains were available for serotyping: 6A (2 cases), 6B (1 case), 9V (1 case), 14 (2 cases), 18C (1 case), 19 (2 cases), 23 F (1 case). The mean length of stay in hospitalized patients was 15.2 days (range: 3-25 days). Three patients died (case fatality rate: 8.5%) and all of them had meningitis. No sequelae were found in survivors. Conclusions The annual incidence of IPD in Malaga is similar to that in other regions but lower than that in the United States and northern regions of Spain. However, the incidence of pneumococcal meningitis does not vary significantly with respect to other reports and even surpasses that reported in other series. The serotype distribution observed supports the use of the heptavalent pneumococcal conjugate vaccine at this age, especially in children under 2 years of age. Its possible epidemiological impact should be monitored.