Efficacy of rectal artesunate compared with parenteral quinine in initial treatment of moderately severe malaria in African children and adults: a randomised study.

BACKGROUND: Many patients with malaria of increasing severity cannot take medicines orally, and delay in injectable treatment can be fatal. We aimed to assess the reliability of absorption, antimalarial efficacy, and tolerability of a single rectal dose of artesunate in the initial management of moderately severe falciparum malaria. METHODS: 109 children and 35 adults were randomly assigned to rectal artesunate (single dose of about 10 mg/kg) or parenteral quinine treatment (10 mg/kg at 0, 4, and 12 h). The primary endpoint was the proportion of patients with peripheral asexual parasitaemia of less than 60% of that at baseline after 12 h. Secondary endpoints were clinical response and concentrations of drug in plasma. Analysis was by intention-to-treat. FINDINGS: All artesunate-treated patients had pharmacodynamic or pharmacokinetic evidence of adequate drug absorption. 80 (92%) of 87 artesunate-treated children had a 12 h parasite density lower than 60% of baseline, compared with three of 22 (14%) receiving quinine (relative risk 0.09 [95% CI 0.04-0.19]; p<0.0001). In adults, parasitaemia at 12 h was lower than 60% of baseline in 26 (96%) of 27 receiving artesunate, compared with three (38%) of eight receiving quinine (relative risk 0.06 [0.01-0.44]; p=0.0009). These differences were greater at 24 h. Clinical response was equivalent with rectal artesunate and parenteral quinine. INTERPRETATION: A single rectal dose of artesunate is associated with rapid reduction in parasite density in adults and children with moderately severe malaria, within the initial 24 h of treatment. This option is useful for initiation of treatment in patients unable to take oral medication, particularly where parenteral treatment is unavailable.

Blood-brain barrier function in cerebral malaria in Malawian children.

Cerebral malaria (CM) is a serious complication of Plasmodium falciparum infection. Binding of parasitized erythrocytes to cerebral endothelium plays a key role in disease pathogenesis. Central nervous system signs and symptoms (coma, seizures, raised intracranial pressure) predominate in African children, whereas in adults, multiorgan system failure is more common. In this study we investigated whether changes in blood-brain barrier (BBB) structure and function are compatible with the signs and symptoms observed in Malawian children with CM. Immunohistochemistry on autopsy brain tissues from eight cases of CM showed activation of endothelial cells and macrophages, and disruption of endothelial intercellular junctions in vessels containing sequestered parasitized erythrocytes, but no gross leakage of plasma proteins. Examination of the partition of albumin between circulating plasma and the cerebrospinal fluid from 72 cases of CM showed subtle but measurable changes compatible with impaired BBB function in malaria. These findings suggest that BBB breakdown occurs in areas of parasite sequestration in CM in African children.

Cytokine expression in the brain in human cerebral malaria.

Evidence from clinical studies and murine models supports a role for cytokines in the pathogenesis of human cerebral malaria (CM). In this study, reverse transcriptase-polymerase chain reaction (RT-PCR) was used to investigate expression of mRNA for transforming growth factor (TGF)-beta, interleukin (IL)-1beta, and tumor necrosis factor (TNF)-alpha in human postmortem tissue. Immunohistochemistry was used to examine the distribution of cytokine protein. TGF-beta was expressed in normal brain, in CM, and in meningitis and encephalitis. IL-1beta was absent from normal brain but was detected in CM and other cerebral infections. TNF-alpha mRNA was expressed only in CM, although TNF-alpha protein was also seen in meningitis. Cytokine mRNA expression in the brain did not correlate with the density of parasitized erythrocytes detected using RT-PCR for major surface protein-2. This report of RT-PCR on postmortem human tissues infected with CM demonstrates induction of the proinflammatory cytokines TNF-alpha and IL-1beta in the brain.

Causes and outcome of bacterial meningitis in Malawian children.

598 children with bacterial meningitis were admitted to the paediatric wards of the Queen Elizabeth Central Hospital (QECH), Blantyre, Malawi from July 1997 - March 2001. Patients were followed up at 1 and 6 months after hospital discharge when physical, neurological, developmental and hearing assessments were made. The most common causes of pyogenic meningitis were Streptococcus pneumoniae (40%), Haemophilus influenzae type b (28%), Neisseria meningitidis (11%), Salmonella species (5%). There was no growth on culture in 13% of cases. The overall mortality was 31% and 38% were left with significant sequelae. Indicators for a poor prognosis were younger age, lower coma score on admission, bacterial cause, nutritional status and HIV positivity.

Dexamethasone treatment in childhood bacterial meningitis in Malawi: a randomised controlled trial.

BACKGROUND: Steroids are used as adjuvant treatment in childhood pyogenic meningitis to attenuate host inflammatory responses to bacterial invasion. We aimed to assess the effectiveness of dexamethasone in management of acute bacterial meningitis in a developing country. METHODS: In a double-blind, placebo controlled trial, we included 598 children with pyogenic meningitis who had been admitted to the children's wards of the Queen Elizabeth Central Hospital, Blantyre, Malawi. We did physical, neurological, developmental, and hearing assessments at 1 and 6 months after discharge. The primary outcome was overall death. Secondary outcomes included sequelae, in-hospital deaths, and death after discharge. Analysis was done by intention to treat. FINDINGS: Of the 598 included children, 307 (51%) were assigned to dexamethasone and 295 (49%) to placebo. 338 (40%) of 598 patients had Streptococcus pneumoniae, 170 (28%) Haemophilus influenzae type b, 66 (11%) Neisseria meningitidis, and 29 (5%) Salmonella spp. 78 (13%) patients had no growth on culture. The number of overall deaths was the same in the two treatment groups (relative risk 1.00 [95% CI 0.8-1.25], p=0.93). At final outcome, sequelae were identified in 84 (28%) of children on steroids and in 81 (28%) on placebo (relative risk 0.99 [95% CI 0.78-1.27], p=0.97). The number of children dying in hospital did not differ between groups. INTERPRETATION: Steroids are not an effective adjuvant treatment in children with acute bacterial meningitis in developing countries.