Invasive meningococcal infection in Western Australia

Abstract

Objectives: To review signs and symptoms in children diagnosed with meningococcal infection; to assess age, sex and race distribution of meningococcal infection; and to assess associations of the presenting features with morbidity and mortality. Design: Retrospective case notes review for a 5-Year period. Subjects: 105 patients aged between 19 days and 13 years. Main data reviewed: Temperature, blood pressure, heart rate, respiratory rate, type of rash, age, sex, race and outcome. Results: Of the 105 patients, 67.6% were Caucasian, 27.6% Aboriginal and 4.8% of other origin. There were 14.3% patients under 3 months of age (2.9% neonates), 48.6% between 3 months and 2 years, 21% between 2 and 4 years and 16.2% older than 4 years. The male:female ratio was 1.4. Features at presentation in decreasing order of frequency were: fever (89.5%), tachypnoea (73.3%), rash (59% [maculopapular 17.1%, petechial 27.6% and purpuric 14.3%]), vomiting (52.4%), irritability (44.8%), tachycardia (37.5%), lethargy (36.2%), neck stiffness (32.4%) and non-specific immediately preceding illness (15.2%). Purpura and a reduced systolic blood pressure were significantly associated with an increased risk of mortality, purpura and reduced diastolic blood pressure with an increased risk of morbidity. Initial misdiagnosis occurred in 17.1% of cases, with the majority of those misdiagnosed (83.3%) aged less than 2 years. Predominant serotyping was Group B followed by Group C. Major findings were a marked male preponderance in patients under 3 months of age. The incidence of meningococcal infection in the Aboriginal population was approximately six times that in the non-Aboriginal population. The yearly incidence of meningococcal disease during the study period ranged from 5.2 to 10.5 per 100.000. Long-term morbidity occurred in 8.6% of cases and mortality was 8.6%. Higher morbidity and mortality figures were found in those with septicaemia alone. Children referred from peripheral hospitals had a higher mortality but a comparable morbidity.