Vol. 5, No. 4 Printed in Great Britain

International Journal of Epidemiology © Oxford University Press 1976

Acute Bacterial Meningitis: where do children die? M. J. GOLDACRE1 Goldacre, M. J . (Department of Social and Community Medicine, University of Oxford, 8 Keble Road, Oxford, England). Acute bacterial meningitis: where do children die? International Journal of Epidemiology 1976, 5: 343-347. The case-fatality rate for acute bacterial meningitis in childhood is still disappointingly high. A review of 687 cases of acute bacterial meningitis including 72 deaths, identified in a defined population of children under ten years of age, was done to determine where patients were treated and where they died. Ten per cent of all hospital admissions were to infectious-disease hospitals, 16 per cent to teaching hospitals, and 74 per cent to general, non-teaching ('regional-board') hospitals. The case-fatality rates associated with these hospitals were three per cent, three per cent and 11 per cent respectively. The difference between regional-board and other hospitals was smaller, although still present, when children who died within a few hours of hospital admission were excluded from the analysis. Twenty-two per cent of all deaths (10 children who died outside hospital and six who were certified dead on admission) occurred before specialist care was reached. It may be possible to reduce the mortality from this disease by improving facilities for treatment in some hospitals. There is, however, an important residue of deaths—those which occur before hospital care is reached and, no doubt, some of those which occur soon after hospital admission—which would be unaffected by such improvements.

15 years and it lags disappointingly behind that in a dozen other countries (7, 8). By contrast, the mortality rate for older children in England and Wales compares favourably with that in most other countries. These rates are probably determined to a major extent by factors other than medical care. However, although a relatively infrequent cause of death, bacterial meningitis is a life-threatening disease in which treatment has a profound effect on the outcome—possibly as great as that for any childhood illness. As such, deaths from this disease merit study. For these reasons, it was considered useful to describe, in a defined population, where children with acute bacterial meningitis are treated and where they die.

INTRODUCTION

Prior to the introduction of specific therapy, the majority of children with bacterial meningitis died (1, 2). The effect of antimicrobial therapy on the course of the illness is usually dramatic. 'Untreated it is almost 100 per cent fatal . . . with delayed or inadequate treatment the mortality is still high . . . yet with early diagnosis and appropriate treatment practically all children with acute bacterial meningitis can and should recover' (3). However, the case-fatality rate for this disease is currently reported at 10-15 per cent in developed countries (4, 5), and there seems to have been no improvement on this over the last two decades (4, 6). There are three possible reasons why this rate has not been further reduced. First, medical care may sometimes be applied inadequately to prevent avoidable death. Second, medical care may sometimes be reached too late to prevent avoidable death. Third, a proportion of deaths may be unavoidable within the limits of current medical practice.

MATERIAL AND METHODS

The study attempted to identify all cases of acute bacterial meningitis, meningococcal disease and acute meningitis of presumed bacterial aetiology (sterile pyogenic meningitis which had been treated in hospital as bacterial), occurring in the years 1969 to 1973 in children under ten years of age in the North-West Metropolitan region of England (north-west London and adjacent counties, population 630,000 children). The diagnostic criteria used in the study have been described in detail (9). Cases were sought from hospital discharge data

Deaths in infancy and childhood are currently of special interest in England and Wales. The (all causes) postneonatal mortality rate, deaths between four weeks and one year of age, has shown little sign of improvement here over the last 1 Lecturer, Department of Social and Community Medicine, University of Oxford, 8 Keble Road, Oxford, England

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INTERNATIONAL JOURNAL OF EPIDEMIOLOGY

(Hospital Activity Analysis and individual hospitals, diagnostic indexes), death certificates, infectiousdisease notifications, and microbiology records in each hospital. The case notes for the patients identified were then obtained. Clinical and laboratory data and a record of treatment received were abstracted from the case notes onto a structured checklist. Times of admission and death for children who died less than 24 hours after hospital admission were available either from the case notes or from autopsy reports. This report is concerned with children who developed the acute illness outside hospital in the absence of known predisposing disease. Accordingly, neonatal cases which developed before discharge of the newborn infant from hospital, readmissions for sequelae of an earlier attack of acute meningitis, and cases in children with neuroanatomical lesions (mainly spina bifida or skull fracture) are excluded. Data on a total of 687 cases are considered. In the results which follow, the age given is the age at diagnosis. Hospitals associated with teaching hospitals, as so designated in The Medical Directory (10), are included as teaching hospitals. Infectious-disease hospitals are those listed as separate hospitals and on a separate site from general hospitals: infectious-disease beds in a general hospital are included with the respective general hospital. All other hospitals are termed regionalboard hospitals. Patients who were transferred between hospitals have been allocated to the hospital to which they were admitted initially. RESULTS

The number of cases identified was 687, including 72 deaths, which represents a case fatality rate

(CFR) of 10 • 5 per cent. There was no record of any diagnosed case of acute bacterial meningitis treated successfully without hospital care; but 10 patients (in whom the diagnosis was made at autopsy) died outside hospital. Of the remainder, 65 patients were admitted to infectious-disease hospitals (10 per cent), 106 to teaching hospitals (16 per cent), and 506 to regional-board hospitals (74 per cent). The CFRs associated with these hospitals were three per cent, three per cent and 11 per cent respectively (Table I). Six patients were certified dead at the time of admission to hospital, one in each of the teaching and infectious-disease group and four in the regional-board hospitals. The majority of infants under four weeks of age (and all fatal cases in this age-group) were admitted to regional-board hospitals. This accounts for the relatively high proportion of 'other named organisms' in such hospitals (Table II), as most of these (mainly coliform organisms) occurred in neonatal meningitis. Although few in number, cases of neonatal meningitis are important because the prognosis is always very poor in this age-group (11). Regionalboard hospitals appear to do as well as the others with haemophilus but not with the meningococcus. Overall, if the CFRs found for each organism in the regional-board group are applied to the number of cases of each organism in the other hospital groups, the expected number of deaths is 11-5 and 7-1 for teaching and infectious-disease hospitals respectively. If the CFRs found at each age in the regional-board hospitals are applied to the number of cases at each age in the other hospital groups, the expected number of deaths is 10-9 and 6-2 respectively. These compare with three and two deaths observed, respectively. Several features of pre-hospital care have been reviewed, including the

TABLE I

Hospital of admission by age-group Type of hospital Number of cases (deaths) and proportion of cases Age

Teaching Number Less than 4 weeks 4 weeks—1 year 1-4 years 5-9 years Total Case fatality rate, %

%

Regional Board Number /o

Infectious Disease Number /a

Total Number

Case fatality rate %

2(0) 37(1) 50(2) 17(0)

1-9 34-9 47-2 160

22(11) 170 (23) 230 (18) 84 (5)

4-3 33-6 45-5 16-6

1(0) 18(1) 27(0) 19(1)

1-5 27-7 41-6 29-2

25(11) 225 (25) 307 (20) 120 (6)

440 111 6-5 50

106 (3) 2-8

1000

506 (57) 11-3

1000

65(2) 31

1000

677 (62) 9-2*

9-2

(10 patients died outside hospital) *X2 for difference in case-fatality rates between types of hospital = 11-35,2 DF, P

Acute bacterial meningitis: where do children die?

The case-fatality rate for acute bacterial meningitis in childhood is still disappointingly high. A review of 687 cases of acute bacterial meningitis ...
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