An open randomized clinical study of intrarectal versus infused Quinimax for the treatment of childhood cerebral malaria in Niger

The aetiologies, mortality, and disability of non-traumatic coma in African children: a systematic review and meta-analysis

BACKGROUND

Non-traumatic coma in African children is a common life-threatening presentation often leading to hospital attendance. We aimed to estimate the distribution of non-traumatic coma causes and outcomes, including disease-specific outcomes, for which evidence is scarce.

METHODS

We systematically reviewed MEDLINE, Embase, and Scopus databases from inception to Feb 6, 2024. We included studies recruiting children (aged 1 month to 16 years) with non-traumatic coma (Blantyre Coma Scale score ≤2, ie deep coma or comparable alternative) from any African country. Disease-specific studies were included if outcomes were reported. Primary data were requested where required. We used a DerSimonian-Laird random effects model to calculate pooled estimates for prevalence of causes, mortality, and morbidity (in-hospital and post-discharge), including analysis of mortality by temporality. This study was registered with PROSPERO (CRD4202014193).

FINDINGS

We screened 16 666 articles. 138 studies were eligible for analysis, reporting causes, outcome data, or both from 35 027 children with non-traumatic coma in 30 African countries. 114 (89%) of 128 studies were determined to be high quality. Among the causes, cerebral malaria had highest pooled prevalence at 58% (95% CI 48-69), encephalopathy of unknown cause was associated with 23% (9-36) of cases, and acute bacterial meningitis was the cause of 10% (8-12) of cases, with all other causes representing lower proportions of cases. Pooled overall case-fatality rates were 17% (16-19) for cerebral malaria, 37% (20-55) for unknown encephalopathy, and 45% (34-55) for acute bacterial meningitis. By meta-regression, there was no significant difference in cerebral malaria (p=0·98), acute bacterial meningitis (p=0·99), or all-cause coma (p=0·081) mortality by year of study. There was no substantial difference in deaths associated with cerebral malaria in-hospital compared with post-discharge (17% [16-19] vs (18% [16-20]). Mortality was higher post-discharge than in-hospital in most non-malarial comas, including acute bacterial meningitis (39% [26-52]) vs 53% [38-69]). Disability associated with cerebral malaria was 11% (9-12). Pooled disability outcomes associated with other non-malarial diseases were largely absent.

INTERPRETATION

The prevalence and outcomes of cerebral malaria and meningitis associated with non-traumatic coma were strikingly static across five decades. Enhanced molecular and radiological diagnostics, investment, policy making, community awareness, and health service provision are all required to facilitate earlier referral to specialist centres, to drive a step-change in diagnostic yield and treatment options to improve these outcomes.

FUNDING

Wellcome Trust.

TRANSLATIONS

For the Chichewa, French and Portuguese translations of the abstract see Supplementary Materials section.

Clinical features and outcome in children with severe Plasmodium falciparum malaria: a meta-analysis

Background

Although global malaria mortality is declining, estimates may not reflect better inpatient management of severe malaria (SM) where reported case fatality rates (CFRs) vary from 1–25%.

Methods

A meta-analysis of prospective studies of SM was conducted to examine i) whether hypothesized differences between clinical features and outcome in Melanesian compared with African or Asian children really exist, and ii) to explore temporal changes in overall and complication-specific CFRs. The proportions of different SM complications and, overall and complication-specific CFRs were incorporated into the meta-analysis. Adjustments were made for study-level covariates including geographic region, SM definition, artemisinin treatment, median age of participants and time period.

Findings

Sixty-five studies were included. Substantial heterogeneity (I²>80%) was demonstrated for most outcomes. SM definition contributed to between-study heterogeneity in proportions of cerebral malaria (CM), metabolic acidosis (MA), severe anemia and overall CFR, whilst geographic region was a significant moderator in for CM and hypoglycemia (HG) rates. Compared with their African counterparts, Melanesian children had lower rates of HG (10% [CI95 7–13%] versus 1% [0–3%], P<0.05), lower overall CFR (2% [0–4%] versus 7% [6–9%], P<0.05) and lower CM-specific CFR (8% [0–17%] versus 19% [16–21%], P<0.05). There was no temporal trend for overall CFR and CM-specific CFR but declining HG- and MA- specific CFRs were observed.

Interpretation

These data highlight that recent estimates of declining global malaria mortality are not replicated by improved outcomes for children hospitalized with SM. Significant geographic differences in the complication rates and subsequent CFRs exist and provide the first robust confirmation of lower CFRs in Melanesian children, perhaps due to less frequent HG.

Treatment of African children with severe malaria - towards evidence-informed clinical practice using GRADE

Background

Severe malaria is a major contributor of deaths in African children up to five years of age. One valuable tool to support health workers in the management of diseases is clinical practice guidelines (CPGs) developed using robust methods. A critical assessment of the World Health Organization (WHO) and Kenyan paediatric malaria treatment guidelines with quinine was undertaken, with a focus on the quality of the evidence and transparency of the shift from evidence to recommendations.

Methods

Systematic reviews of the literature were conducted using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) tool to appraise included studies. The findings were used to evaluate the WHO and Kenyan recommendations for the management of severe childhood malaria.

Results

The WHO 2010 malaria guidance on severe malaria in children, which informed the Kenyan guidelines, only evaluated the evidence on one topic on paediatric care using the GRADE tool. Using the GRADE tool, this work explicitly demonstrated that despite the established use of quinine in the management of paediatric cases of severe malaria for decades, low or very low quality evidence of important outcomes, but not critical outcomes such as mortality, have informed national and international guidance on the paediatric quinine dosing, route of administration and adverse effects.

Conclusions

Despite the foreseeable shift to artesunate as the primary drug for treatment of severe childhood malaria, the findings reported here reflect that the particulars of quinine therapeutics for the management of severe malaria in African children have historically been a neglected research priority. This work supports the application of the GRADE tool to make transparent recommendations and to inform advocacy efforts for a greater research focus in priority areas in paediatric care in Africa and other low-income settings.

Quinine, an old anti-malarial drug in a modern world: role in the treatment of malaria

Quinine remains an important anti-malarial drug almost 400 years after its effectiveness was first documented. However, its continued use is challenged by its poor tolerability, poor compliance with complex dosing regimens, and the availability of more efficacious anti-malarial drugs. This article reviews the historical role of quinine, considers its current usage and provides insight into its appropriate future use in the treatment of malaria. In light of recent research findings intravenous artesunate should be the first-line drug for severe malaria, with quinine as an alternative. The role of rectal quinine as pre-referral treatment for severe malaria has not been fully explored, but it remains a promising intervention. In pregnancy, quinine continues to play a critical role in the management of malaria, especially in the first trimester, and it will remain a mainstay of treatment until safer alternatives become available. For uncomplicated malaria, artemisinin-based combination therapy (ACT) offers a better option than quinine though the difficulty of maintaining a steady supply of ACT in resource-limited settings renders the rapid withdrawal of quinine for uncomplicated malaria cases risky. The best approach would be to identify solutions to ACT stock-outs, maintain quinine in case of ACT stock-outs, and evaluate strategies for improving quinine treatment outcomes by combining it with antibiotics. In HIV and TB infected populations, concerns about potential interactions between quinine and antiretroviral and anti-tuberculosis drugs exist, and these will need further research and pharmacovigilance.

Knowledge and acceptability of the rectal treatment route in Laos and its application for pre-referral emergency malaria treatment

BACKGROUND

Rectal artesunate has been shown to reduce death and disability from severe malaria caused by delays in reaching facilities capable of providing appropriate treatment. Acceptability of this mode of drug delivery in Laos is not known. In 2009 the acceptability of rectal treatments was evaluated among the general Lao population and Lao doctors in a national survey.

METHODS

A cross sectional survey was performed of 985 households selected through a multi-stage random sampling process from 85 villages in 12/18 provinces and of 315 health staff randomly selected at each administrative level.

RESULTS

Out of 985 families, 9% had used the rectal route to treat children (the main indication was seizures or constipation). The population considered it less effective than other routes. Other concerns raised included pain (28%), discomfort for children (40%) and the possibility of other side effects (20%). Of 300 health staff surveyed (nurses 44%, doctors 66%), only 51% had already used the rectal route with a suppository, mostly to treat fever (76%). Health staff working in provincial hospitals had more experience of using the rectal route than those in urban areas. The majority (92%) were keen to use the rectal route to treat malaria although oral and intramuscular routes were preferred and considered to be more efficacious.

DISCUSSION AND CONCLUSION

Use of rectal treatments is uncommon in Laos and generally not considered to be very effective. This view is shared by the population and health care workers. More information and training are needed to convince the population and health staff of the efficacy and advantages of the rectal route for malaria treatment.

Intrarectal quinine versus intravenous or intramuscular quinine for treating Plasmodium falciparum malaria

BACKGROUND

In children with falciparum malaria, a proprietary quinine preparation (adjusted to make it less acidic) administered rectally may be easier to use and less painful than intramuscular or intravenous administration. However, rectal quinine may be less effective.

OBJECTIVES

To compare intrarectal quinine with intravenous or intramuscular quinine for treating malaria caused by Plasmodium falciparum.

SEARCH STRATEGY

In May 2008, we searched the Cochrane Infectious Diseases Group Specialized Register, CENTRAL (The Cochrane Library 2008, Issue 2), MEDLINE, EMBASE, LILACS, and CINAHL. We also searched conference proceedings, contacted individual researchers and a pharmaceutical company, and checked reference lists.

SELECTION CRITERIA

Randomized and quasi-randomized controlled trials comparing intrarectal quinine with intramuscular and intravenous quinine for treating people with uncomplicated and severe Plasmodium falciparum malaria.

DATA COLLECTION AND ANALYSIS

We independently assessed each trial's risk of bias quality and extracted data, including adverse event data. We analysed dichotomous data using the odds ratio and continuous data using the mean difference.

MAIN RESULTS

Ten randomized controlled trials, all involving children only (total of 1417 children), fulfilled the inclusion criteria. The same investigator was involved in nine of the trials. Seven trials compared proprietary intrarectal with intravenous quinine, and seven trials compared it with intramuscular treatment. We detected no statistically significant difference between intrarectal and intravenous or intramuscular routes for death, parasite clearance by 48 hours and seven days, parasite clearance time, fever clearance time, coma recovery time, duration of hospitalization, and time to drinking. The trials reporting on these outcomes were small, which resulted in large confidence intervals for all outcomes apart from duration of hospitalization. One large trial (898 children) reported that intrarectal was less painful than intramuscular administration.

AUTHORS' CONCLUSIONS

We detected no difference in the effect on parasites and clinical illness for intrarectal quinine, but most trials were small. Pain may be less with intrarectal proprietary, buffered quinine preparations (made less acidic by adjustment of the pH to 4.5). Further larger trials in patients with severe malaria and in adults are required before the intrarectal route can be recommended.

Acceptability and efficacy of intra-rectal quinine alkaloids as a pre-transfer treatment of non-per os malaria in peripheral health care facilities in Mopti, Mali

BACKGROUND

The acceptability and efficacy of a new kit with a new formulation of quinine alkaloids designed for the intra-rectal administration in the treatment of non-per os malaria was assessed in the peripheral health care system of Mopti, Mali.

METHODS

A single-arm trial was conducted from August 2003 to January 2004. An initial dose of diluted quinine alkaloids (20 mg/kg Quinimax) was administered by the intra-rectal route to children with presumptive non per-os malaria at six peripheral heath care centres. The children were then referred to two referral hospitals where standard inpatient care including intravenous route were routinely provided. A malaria thick smear was done at inclusion and a second malaria thick smear after arrival at the referral facility, where a more complete clinical examination and laboratory testing was done to confirm diagnosis. Confirmed cases of severe malaria or others diseases were treated according to national treatment guidelines. Cases of non per-os malaria received a second dose of intra rectal quinine alkaloids. Primary outcome was acceptability of the intra rectal route by children and their parents as well as the ease to handle the kit by health care workers.

RESULTS

The study included 134 children with a median age of 33 months and 53.7% were male. Most of the children (67%) and 92% of parents or guardians readily accepted the intra-rectal route; 84% of health care workers found the kit easy to use. At the peripheral health care centres, 32% of children had a coma score < or = 3 and this was reduced to 10% at the referral hospital, following one dose of intra-rectal quinine alkaloids (IRQA). The mean time to availability of oral route treatment was 1.8 +/- 1.1 days. Overall, 73% of cases were confirmed severe malaria and for those the case fatality rate was 7.2%.

CONCLUSION

IRQA was well accepted by children, their parents/guardians and by the health workers at peripheral health facilities in Mopti, Mali. There was also a quick recovery from deep coma and a reduced case fatality rate in severe malaria.

Safety and efficacy of rectal compared with intramuscular quinine for the early treatment of moderately severe malaria in children: randomised clinical trial

OBJECTIVE

To compare the safety and efficacy of quinine given by the rectal route with quinine given by the intramuscular route in children with moderately severe Plasmodium falciparum malaria.

DESIGN

Randomised, open, clinical trial.

SETTING

Health centre in Burkina Faso.

PARTICIPANTS

898 children with moderately severe P falciparum malaria who were unable to take oral treatment.

INTERVENTION

Rectal quinine (20 mg/kg diluted to 30 mg/ml in water solution) or intramuscular quinine (12.5 mg/kg) every 12 hours until oral quinine could be taken.

MAIN OUTCOME MEASURES

Primary safety outcome was the presence of blood in stools and secondary safety outcome was diarrhoea. Primary efficacy outcome was early treatment failure and secondary efficacy outcomes were late clinical and parasitological failures, fever clearance time, and time to oral intake.

RESULTS

Blood in stools and diarrhoea were more common in children given quinine by the rectal route than by the intramuscular route (blood in stools: 5% v 1%, absolute difference 3.9%, 95% confidence interval 1.8% to 6.1%; diarrhoea: 5% v 1%, 3.5%, 1.3% to 5.7%). On anoscopy, inflammatory lesions (9/248, 3%) were associated with bloody striations in stools. Side effects of rectal quinine were rare and transitory. Local pain (90%), inflammation (79%), and transient impairment of mobility (15%) were observed with intramuscular quinine. Early treatment failure was higher in the rectal group (6% v 3%, absolute difference 3.0%, 95% confidence interval 0.2% to 5.9%). All except two children in each group had negative blood slide results at day 5. Fever recurrence at day 7 was higher in the intramuscular group (37/375 v 18/395, absolute difference 5.3%, 1.6% to 8.9%). Other efficacy outcomes (late clinical failure, late parasitological failure, fever clearance time, time to starting oral intake and rate of deterioration to severe malaria) did not differ.

CONCLUSION

Quinine given by the rectal route has an acceptable safety profile and could be used in the early management of moderately severe malaria in children in sub-Saharan Africa, halting progression to severe disease.

Pathogenesis, clinical features, and neurological outcome of cerebral malaria

Cerebral malaria is the most severe neurological complication of Plasmodium falciparum malaria. Even though this type of malaria is most common in children living in sub-Saharan Africa, it should be considered in anybody with impaired consciousness that has recently travelled in a malaria-endemic area. Cerebral malaria has few specific features, but there are differences in clinical presentation between African children and non-immune adults. Subsequent neurological impairments are also most common and severe in children. Sequestration of infected erythrocytes within cerebral blood vessels seems to be an essential component of the pathogenesis. However, other factors such as convulsions, acidosis, or hypoglycaemia can impair consciousness. In this review, we describe the clinical features and epidemiology of cerebral malaria. We highlight recent insights provided by ex-vivo work on sequestration and examination of pathological specimens. We also summarise recent studies of persisting neurocognitive impairments in children who survive cerebral malaria and suggest areas for further research.

Intrarectal quinine for treating Plasmodium falciparum malaria: a systematic review

Background

In children with malaria caused by Plasmodium falciparum, quinine administered rectally may be easier to use and less painful than intramuscular or intravenous administration. The objective of this review was to compare the effectiveness of intrarectal with intravenous or intramuscular quinine for treating falciparum malaria.

Methods

All randomized and quasi-randomized controlled trials comparing intrarectal with intramuscular or intravenous quinine for treating people with falciparum malaria located through the following sources were included: Cochrane Infectious Diseases Group Specialized Register, CENTRAL, MEDLINE, EMBASE, LILACS and CINAHL. Trial quality was assessed and data, including adverse event data, were extracted. Dichotomous data were analysed using odds ratios and continuous data using weighted mean difference.

Results

Eight randomized controlled trials (1,247 children) fulfilled the inclusion criteria. The same principal investigator led seven of the trials. Five compared intrarectal with intravenous quinine, and six compared intrarectal with intramuscular treatment. No statistically significant difference was detected for death, parasite clearance by 48 hours and seven days, parasite and fever clearance time, coma recovery time, duration of hospitalization and time before drinking began. One trial (898 children) reported that intrarectal was less painful than intramuscular administration.

Conclusion

No difference in the effect on parasites and clinical illness was detected for the use of intrarectal quinine compared with other routes, but most trials were small. Pain during application may be less with intrarectal quinine. Further larger trials, in patients with severe malaria and in adults, are required before the intrarectal route could be recommended.

Intrarectal quinine for treating Plasmodium falciparum malaria

BACKGROUND

In children with falciparum malaria, quinine administered rectally may be easier to use and less painful than intramuscular or intravenous administration. However, it may be less effective.

OBJECTIVES

To compare intrarectal quinine with intravenous or intramuscular quinine for treating malaria caused by Plasmodium falciparum.

SEARCH STRATEGY

We searched the Cochrane Infectious Diseases Group Specialized Register (July 2004), CENTRAL (The Cochrane Library Issue 3, 2004), MEDLINE (1966 to July 2004), EMBASE (1974 to July 2004), LILACS (1982 to July 2004), and CINAHL (1982 to July 2004). We also searched conference proceedings, contacted individual researchers and a pharmaceutical company, and checked reference lists.

SELECTION CRITERIA

Randomized and quasi-randomized controlled trials comparing intrarectal quinine with intramuscular and intravenous quinine for treating people with uncomplicated and severe falciparum malaria.

DATA COLLECTION AND ANALYSIS

We independently assessed trial quality and extracted data, including adverse event data. We analysed dichotomous data using odds ratios and weighted mean difference for continuous data.

MAIN RESULTS

Eight randomized controlled trials (involving 1247 children) fulfilled the inclusion criteria. The same principal investigator led seven of the trials. Five trials compared intrarectal with intravenous quinine, and six trials compared it with intramuscular treatment. We detected no statistically significant difference between intrarectal and intravenous or intramuscular routes for death, parasite clearance by 48 hours and 7 days, parasite clearance time, fever clearance time, coma recovery time, duration of hospitalization, and time to drinking. The trials reporting on these outcomes were small, which resulted in large confidence intervals for all outcomes apart from duration of hospitalization. One large trial (898 children) reported that intrarectal was less painful than intramuscular administration.

AUTHORS' CONCLUSIONS

We detected no difference in the effect on parasites and clinical illness for intrarectal quinine, but most trials were small. Pain may be less with intrarectal quinine. Further larger trials, in patients with severe malaria and in adults, are required before the intrarectal route can be recommended.

Dose-dependent resorption of quinine after intrarectal administration to children with moderate Plasmodium falciparum malaria

The pharmacokinetics of increasing doses of an intrarectal Cinchona alkaloid combination containing 96.1% quinine, 2.5% quinidine, 0.68% cinchonine, and 0.67% cinchonidine (Quinimax) was compared to that of parenteral regimens in 60 children with moderate malaria. Quinine exhibited a nonlinear pharmacokinetics, suggesting a saturation of rectal resorption. When early rejections appeared, blood quinine concentrations decreased by 30 to 50% and were restored by an immediate half-dose administration of the drug. Rectal administration of doses of 16 or 20 mg/kg of body weight led to concentration-time profiles in blood similar to those of parenteral regimens and could be an early treatment of childhood malaria.

Cerebral malaria: optimising management

Cerebral malaria is one of the most common nontraumatic encephalopathies in the world. Children living in sub-Saharan Africa bear the brunt of the disease, but cerebral malaria is being seen increasingly in adults throughout the world, including outside malarious areas. There are differences in the clinical presentation and pathophysiology between African children and nonimmune adults from any region. Mortality is high (10-20%). Parenteral antimalarials are the only interventions that have been shown to affect outcome. The cinchona alkaloids (quinine and quinidine) are the mainstay of antimalarial treatment, but the artemisinin derivatives are increasingly being used. Aggressive treatment and prevention of convulsions may be important, particularly in children. Other ancillary treatments that can be used to augment standard antimalarial drugs, such as exchange blood transfusions, osmotic diuretics and pentoxifylline, may improve outcome but have not been subjected to rigorous clinical trials. There is little support for corticosteroids or deferoxamine (desferrioxamine) in cerebral malaria. Other adjuncts have not been adequately tested. Further research is required on drugs that interfere with the pathophysiological processes to prevent neurological complications and death.

Intrarectal pharmacokinetics of two formulations of quinine in children with falciparum malaria

OBJECTIVE

To compare the intrarectal bioavailabilities of two parenteral formulations of quinine most available in French- (Cinchona alkaloid mixture) and English (hydrochloride salt) -speaking areas of Africa.

METHODS

The pharmacokinetics of quinine was investigated in four groups of 12 children with acute Plasmodium falciparum malaria receiving 8 mg/kg quinine base every 8 h either as hydrochloride salt or Cinchona alkaloid mixture by a slow 4-h intravenous infusion or intrarectal administration. Body temperature and parasitaemia were monitored, and blood quinine concentrations were measured by means of high-performance liquid chromatography.

RESULTS

At 72 h, all the children were aparasitaemic and apyretic. Quinine C(max) values were higher after intravenous infusion of the hydrochloride salt and Cinchona alkaloid mixture (6.9+/-1.9 micro g/ml and 5.2+/-1.3 micro g/ml) than after intrarectal administration (3.5+/-1.4 micro g/ml and 3.1+/-1.6 micro g/ml), but t(max) values were similar (3.6+/-1.5, 4.2+/-1.0, 4.0+/-1.9, and 4.7+/-2.0 h, respectively). Intrarectal relative bioavailabilities of hydrochloride salt solution (57%) and Cinchona alkaloid mixture (62%) were similar.

CONCLUSION

Whatever the parenteral formulation of quinine, the blood concentration-time profiles of quinine were similar after intrarectal administration. Intrarectal administration of hydrochloride salt solution is a possible mode of quinine delivery in remote rural areas of Africa.

In vitro evaluation of quinidine sensitivity in Brazilian Plasmodium falciparum isolates: comparative analysis to quinine and chloroquine

Falciparum malaria represents a serious and an increasing world public health problem due to the acquired parasite's resistance to the most available drugs. In some endemic areas, quinidine, a diastereoisomer of the antimalarial quinine, has been employed for replacing the latter. In order to evaluate the use of quinidine as an alternative to the increasing loss of quinine effectiveness in Brazilian P. falciparum strains, as has been observed in the Amazon area, we have assayed quinidine, quinine and chloroquine. The in vitro microtechnique was employed. All isolates showed to be highly resistant to chloroquine. Resistance to quinine was not noted although high MIC (minimal inhibitory concentration) values have been observed. These data corroborate the decreasing sensitivity to quinine in strains from Brazil. Quinidine showed IC50 from 0.053 to 4.577 micromol/L of blood while IC50 from 0.053 to 8.132 micromol/L of blood was estimated for quinine. Moreover, clearance of the parasitemia was observed in concentrations lower than that used for quinidine in antiarrhythmic therapy, confirming our previous data. The results were similar to African isolate.

New therapies and changing patterns of treatment for malaria

The launch of the Roll Back Malaria initiative by the World Health Organization in the period under review confirms malaria's place as one of the great public health priorities worldwide. The period 1998-1999 has seen some advances and some disappointments in the treatment of malaria, against a backdrop of spreading drug resistance. Most encouraging is the clear demonstration that intermittent prospective treatment of asymptomatic pregnant women in endemic areas reduces morbidity. The greatest disappointment has been the result of trials with the artemether-benflumetol fixed-dose combination therapy. Questions have been raised about several widely accepted practices, including measurement of quinine levels, exchange transfusion, and the prophylactic use of anticonvulsants in children with cerebral malaria.