Human immunodeficiency virus infection and pediatric bacterial meningitis in developing countries

High mortality amongst adolescents and adults with bacterial meningitis in sub-Saharan Africa: an analysis of 715 cases from Malawi

Mortality from bacterial meningitis in African adults is significantly higher than those in better resourced settings and adjunctive therapeutic interventions such as dexamethasone and glycerol have been shown to be ineffective. We conducted a study analysing data from clinical trials of bacterial meningitis in Blantyre, Malawi to investigate the clinical parameters associated with this high mortality.

Methods

We searched for all clinical trials undertaken in Blantyre investigating bacterial meningitis from 1990 to the current time and combined the data from all included trial datasets into one database. We used logistic regression to relate individual clinical parameters to mortality. Adults with community acquired bacterial meningitis were included if the CSF culture isolate was consistent with meningitis or if the CSF white cell count was >100 cells/mm³ (>50% neutrophils) in HIV negative participants and >5 cells/mm³ in HIV positive participants. Outcome was measured by mortality at discharge from hospital (after 10 days of antibiotic therapy) and community follow up (day 40).

Results

Seven hundred and fifteen episodes of bacterial meningitis were evaluated. The mortality rate was 45% at day 10 and 54% at day 40. The most common pathogens were S.pneumoniae (84% of positive CSF isolates) and N.meningitidis (4%). 607/694 (87%) participants tested were HIV antibody positive. Treatment delays within the hospital system were marked. The median presenting GCS was 12/15, 17% had GCS<8 and 44.9% had a seizure during the illness. Coma, seizures, tachycardia and anaemia were all significantly associated with mortality on multivariate analysis. HIV status and pneumococcal culture positivity in the CSF were not associated with mortality. Adults with community acquired bacterial meningitis in Malawi present with a severe clinical phenotype. Predictors of high mortality are different to those seen in Western settings. Optimising in-hospital care and minimising treatment delays presents an opportunity to improve outcomes considerably.

Risk factors for death and severe sequelae in Malawian children with bacterial meningitis, 1997-2010

BACKGROUND

Acute bacterial meningitis (ABM) causes significant death and disability in children worldwide, with HIV recognized as an established risk factor for infection and negative outcomes. However, additional major risk factors for death and disability in pediatric ABM remain unclear.

METHODS

We conducted a retrospective analysis of case data from 3 departmental studies of ABM involving 1784 children <15 years old who attended Queen Elizabeth Central Hospital in Blantyre, Malawi during 1997 to 2010. Univariate and multivariate logistic regression models were used to estimate the effects of HIV seropositivity, impaired consciousness and causative organism on death and severe sequelae.

RESULTS

Impaired consciousness or coma at the time of admission was strongly associated with death (coma: odds ratio [OR] = 14.4, 95% confidence interval [CI]: 9.42, 22.1) and severe sequelae (Coma: OR = 3.27, 95% CI: 2.02, 5.29) in multivariate logistic regression models. HIV seropositivity was significantly associated with increased odds of death (OR = 1.65, 95% CI: 1.20, 2.26) but not with developing severe sequelae (OR = 0.88, 95% CI: 0.56, 1.38). After adjustment, infection with Salmonella spp. was associated with increased odds of death (OR = 2.11, 95% CI: 1.06, 4.08) and pneumococcal meningitis was associated with increased odds of severe sequelae (OR = 1.84, 95% CI: 1.03, 3.29).

CONCLUSIONS

Impaired consciousness and HIV infection increased the odds of death from ABM in Malawian children. Use of pneumococcal conjugate vaccine could greatly reduce the burden of ABM in Malawi.

[Pneumococcal conjugate vaccine failure in HIV-infected child. Clinical case]

Despite appropriate antimicrobial therapy and vaccination, invasive pneumococcal infections remain associated with significant mortality, especially in selected high-risk groups (asplenic, humoral immunity deficient patients, etc.). We present a 13-year-old caucasian boy with HIV infection (vertical transmission). He received treatment with highly-active antiretroviral therapy (amprenavir, lamivudine and zidovudine) and vaccination with 23-valent vaccine (6 years old) and 7-valent pneumococcal conjugate vaccine (10 years old). His CD4 count and his viral load at these times were 2,063/microl and 13461 cop/ml, when he was 6 years old and 1,315/microl and 32400 cop/ml when he was 10 years old, respectively. The latest CD4 count (1,000/microl) and his viral load (3800 cop/ml) confirmed satisfactory control of the disease. He was referred to our emergency department presenting with fever, head and stomach-ache and vomiting. In the following hours his condition continued to deteriorate and depressed level of consciousness and meningismus were observed. Streptococcus pneumoniae, serotype 18 C, was detected in blood and cerebrospinal fluid cultures. Despite appropriate treatment with antibiotics (cefotaxime and vancomycin) and anti-oedema medications, brain-death was confirmed 24 hours after his admittance.