Haemolytic anaemia after oral artemether-lumefantrine treatment in a patient affected by severe imported falciparum malaria

Therapeutic efficacy and safety of artemether-lumefantrine for uncomplicated Plasmodium falciparum malaria treatment in Metehara, Central-east Ethiopia

BACKGROUND

Malaria remains a major global health problem although there was a remarkable achievement between 2000 and 2015. Malaria drug resistance, along with several other factors, presents a significant challenge to malaria control and elimination efforts. Numerous countries in sub-Saharan Africa have documented the presence of confirmed or potential markers of partial resistance against artemisinin, the drug of choice for the treatment of uncomplicated Plasmodium falciparum malaria. The World Health Organization (WHO) recommends regular surveillance of artemisinin therapeutic efficacy to inform policy decisions.

METHODS

This study aimed to evaluate the therapeutic efficacy of artemether-lumefantrine (AL), which is the first-line treatment for uncomplicated P. falciparum malaria in Ethiopia since 2004. Using a single-arm prospective evaluation design, the study assessed the clinical and parasitological responses of patients with uncomplicated P. falciparum malaria in Metehara Health Centre, central-east Ethiopia. Out of 2332 malaria suspects (1187 males, 1145 females) screened, 80 (50 males, 30 females) were enrolled, followed up for 28 days, and 73 (44 males, 29 females) completed the follow up. The study was conducted and data was analysed by employing the per-protocol and Kaplan-Meier analyses following the WHO Malaria Therapeutic Efficacy Evaluation Guidelines 2009.

RESULTS

The results indicated rapid parasite clearance and resolution of clinical symptoms, with all patients achieving complete recovery from asexual parasitaemia and fever by day (D) 3. The prevalence of gametocytes decreased from 6.3% on D0 to 2.5% on D2, D3, D7, and ultimately achieving complete clearance afterward.

CONCLUSION

The overall cure rate for AL treatment was 100%, demonstrating its high efficacy in effectively eliminating malaria parasites in patients. No serious adverse events related to AL treatment were reported during the study, suggesting its safety and tolerability among the participants. These findings confirm that AL remains a highly efficacious treatment for uncomplicated P. falciparum malaria in the study site after 20 years of its introduction in Ethiopia.

Imported severe Plasmodium falciparum infection in the first trimester of pregnancy complicated by post-artemisinin delayed hemolysis and intrauterine fetal death, a case report

BACKGROUND

Post-artemisinin delayed hemolysis (PADH) is a serious complication in patients who recover from severe malaria after receiving artemisinin-based combined therapy (ACT), including artemether-lumefantrine. In Japan, among the antimalarial drugs recommended by the World Health Organization (WHO) guideline for severe malaria, intravenous quinine gluconate is available only in 29 designated hospitals, and intravenous artesunate is unavailable. Therefore, oral artemether-lumefantrine is occasionally administered as an alternative, even though it may be a suboptimal treatment. In non-endemic settings like Japan, a lack of knowledge of malaria and the side effects, such as post-artemisinin delayed hemolysis caused by the ACT, can have critical consequences. Like our patient, being a primigravida in the early stages of pregnancy is a serious risk factor for severe malaria and must be carefully monitored.

CASE PRESENTATION

This report describes a severe case of imported Plasmodium falciparum malaria complicated by fetal loss and prolonged anemia, requiring frequent blood transfusions. The patient was a previously healthy pregnant Japanese female in her 30 s. She developed a high fever 2 days after returning from Nigeria. The patient fulfilled the severe malaria criteria by WHO. On arrival, an abdominal ultrasound incidentally revealed a fetus of 5 week gestational age with a heartbeat in the uterus. Given her pregnancy and the severity of the disease, she was administered intravenous quinine 16 mg/kg as a loading dose. However, the second dose of quinine was not administered due to frequent vomiting and QTc prolongation. We initiated treatment with oral artemether-lumefantrine, and clearance of parasitemia was confirmed by microscopic observation on day 4. Miscarriage was noted on day 6 after admission. Moreover, the patient became feverish again up to 39 °C, and from days 14 to 22, the patient required multiple blood transfusions due to PADH. On day 40, follow-up was discontinued as the hemoglobin level exceeded 10 g/dL.

CONCLUSIONS

In patients who recover from severe malaria after ACT treatment, monitoring the hemoglobin level for at least a month is strongly recommended for prompt identification of PADH. Travelers to malaria-endemic countries, especially primigravida women, should be provided with adequate information on the risk and prevention of infection.

Post-artesunate Delayed Hemolysis in Patients With Severe Malaria in the United States-April 2019 Through July 2021

BACKGROUND

Studies have demonstrated the safety and efficacy of intravenous artesunate (IVAS) for treatment of severe malaria in endemic and nonendemic countries. However, post-artesunate delayed hemolysis (PADH) is an increasingly recognized phenomenon after its administration. This study describes the prevalence and outcomes of PADH events among severe malaria cases treated with IVAS in the United States.

METHODS

Patients diagnosed with severe malaria and treated with IVAS from April 2019 to July 2021 were included. Demographic, clinical, laboratory, therapeutic, and outcome measures were described using proportions, medians, and interquartile range. Patients reported to experience PADH were compared with those not reported to have PADH, and tests of significance were performed.

RESULTS

Of 332 patients included in our analysis, 9 (2.7%) experienced PADH. The majority of infections in both groups were in non-Hispanic Black individuals. Parasite density (11.0% vs 8.0%), admission hemoglobin (11.0 g/dL vs 11.8 g/dL) were similar in the 2 groups. Total bilirubin levels at admission (4.7 mg/dL vs 2.2 mg/dL) and within 8 hours after completion of IVAS (2.6 mg/dL vs 1.2 mg/dL) were notably higher in PADH patients. Cumulative IVAS dose of >9.5 mg/kg and >3 doses of IVAS were risk factors for PADH. The majority (7 of 9) of PADH cases were diagnosed within 2 weeks after initiation of IVAS. Five patients (56%) required blood transfusions, and all recovered without sequelae.

CONCLUSIONS

PADH is an uncommon and self-limiting adverse event in many cases; weekly monitoring of hemoglobin and hemolytic markers may identify cases requiring intervention in a timely manner.

Post-treatment haemolysis is common following oral artemisinin combination therapy of uncomplicated malaria in travellers

BACKGROUND

Artemisinin combination therapy (ACT) for the treatment of malaria is highly effective, well tolerated and safe. Episodes of delayed hemolysis occur in up to 57.9% of patients with severe malaria treated with intravenous artesunate, mainly caused by 'pitting' of infected red blood cells (RBCs) in the spleen and delayed loss of these once-infected RBCs (oiRBCs). Several reports indicate that post-treatment hemolysis (PTH) also occurs in uncomplicated malaria treated with oral ACT, calling for systematic investigation.

METHODS

Prospective observational study to identify the proportion of patients with PTH after oral ACT, defined as increased lactate dehydrogenase activity and low haptoglobin level on day 14 after treatment. Patients were enrolled at two study centres in Germany and Italy. Study visits took place on days 1, 3, 7, 14, 28. Laboratory investigations included extended clinical routine laboratory tests, quantitative P.f.-HRP2, anti-RBC antibodies, and oiRBCs. State of semi-immunity to malaria was assessed from childhood and ongoing exposure to Plasmodium spp. as per patient history.

RESULTS

A total of 134 patients with uncomplicated malaria and 3-day ACT treatment were recruited. Thirty-seven (37.4%) of 99 evaluable patients with P.f. and none of nine patients with non-P.f. malaria exhibited PTH on d14. Patients with PTH had higher initial parasitaemia, higher oiRBC counts on d3, and a 10-fold decrease in oiRBCs between d7 and d14 compared to patients without PTH. In patients with PTH, loss of haemoglobin (Hb) was 4-fold greater in non-Africans than in Africans (-1.3 vs -0.3 g/dl). Semi-immune African patients with PTH showed markedly increased erythropoiesis on d14 compared to not semi-immune African and non-African patients with PTH.

CONCLUSIONS

PTH is common in patients with uncomplicated malaria and oral ACT. While the observed loss of Hb will not be clinically relevant in most cases, it could aggravate pre-existing anaemia and warrants follow-up examinations in populations at risk.

Case Report: Autoimmune Hemolysis Anemia After Dihydroartemisinin and Piperaquine for Uncomplicated Plasmodium falciparum Malaria

Malaria is still an endemic disease in Africa, with many imported cases in Europe. The standard treatment is intravenous artesunate for severe malaria and oral artemisinin-based combination therapy (ACT) for uncomplicated malaria. Delayed hemolytic anemia (DHA) after intravenous artesunate has been extensively described, and guidelines recommend biological monitoring until 1 month after the end of the treatment. A link with an autoimmune process is still unsure. Nevertheless, cases with positive direct antiglobulin test (DAT) have been reported. Conversely, DHA is not recognized as an adverse effect of oral ACT. Previously, only few cases of DHA occurring after oral ACT without intravenous artesunate administration have been reported. We report the case of a 42-year-old man returning from Togo. He was treated with dihydroartemisinin/piperaquine combination for uncomplicated Plasmodium falciparum malaria, with low parasitemia. Nine days after the end of the treatment, the patient developed hemolytic anemia with positive DAT. Eventually, the patient recovered after corticotherapy. After excluding common causes of autoimmune hemolytic anemia, we considered that dihydroartemisinin/piperaquine treatment was involved in this side effect.

Fatal case of delayed-onset haemolytic anaemia after oral artemether-lumefantrine

Artemisinin derivatives are used globally in the management of falciparum malaria. Postartemisinin delayed haemolysis (PADH) is a recognised adverse event contributing to severe anaemia. To the best of our knowledge, we report the first recorded fatal case of PADH. A 60-year-old woman presented with two episodes of collapse at home and feeling generally unwell. She had recently been treated for uncomplicated falciparum malaria 1 month prior with artemether 80 mg/lumefantrine 480 mg in Congo. Her results on admission revealed an anaemia (haemoglobin 43 g/L), raised lactate dehydrogenase and positive direct antiglobulin test that suggested an intravascular haemolytic process. She made a capacitous decision to refuse blood products in line with her personal beliefs. Despite best supportive treatment, she did not survive. This case highlights the importance of postartemisinin follow-up and should encourage discussion and careful consideration of its use in the context of lack of access to/patient refusal of blood products.

Systematic analysis of direct antiglobulin test results in post-artesunate delayed haemolysis

Background

Post-artesunate delayed haemolysis (PADH) is common after severe malaria episodes. PADH is related to the “pitting” phenomenon and the synchronous delayed clearance of once-infected erythrocytes, initially spared during treatment. However, direct antiglobulin test (DAT) positivity has been reported in several PADH cases, suggesting a contribution of immune-mediated erythrocyte clearance. The aim of the present study was to compare clinical features of cases presenting a positive or negative DAT.

Methods

Articles reporting clinical data of patients diagnosed with PADH, for whom DAT had been performed, were collected from PubMed database. Data retrieved from single patients were extracted and univariate analysis was performed in order to identify features potentially related to DAT results and steroids use.

Results

Twenty-two studies reporting 39 PADH cases were included: median baseline parasitaemia was 20.8% (IQR: 11.2–30) and DAT was positive in 17 cases (45.5%). Compared to DAT-negative individuals, DAT-positive patients were older (49.5 vs 31; p = 0.01), had a higher baseline parasitaemia (27% vs 17%; p = 0.03) and were more commonly treated with systemic steroids (11 vs 3 patients, p = 0.002). Depth and kinetics of delayed anaemia were not associated with DAT positivity.

Conclusions

In this case series, almost half of the patients affected by PADH had a positive DAT. An obvious difference between the clinical courses of patients presenting with a positive or negative DAT was lacking. This observation suggests that DAT result may not be indicative of a pathogenic role of anti-erythrocytes antibodies in patients affected by PADH, but it may be rather a marker of immune activation.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12936-021-03735-w.

Post-artemisinin delayed hemolysis after oral therapy for P. falciparum infection

•

Post-artemisinin delayed hemolysis after oral artemisinin therapy.

•

Hemolytic anemia requiring transfusion after severe malaria infection and oral artemether-lumefantrine.

•

Oral artemisinin therapy can cause post-artemisinin delayed hemolysis without exposure to IV artesunate.

•

Corticosteroid therapy may reduce blood transfusion burdens in post-artemisinin delayed hemolysis.

A documented side-effect of artemisinin therapy is post-artemisinin delayed hemolysis (PADH), primarily occurring after parenteral treatment for severe P. falciparum infections. PADH has been infrequently reported after oral therapy and is rarely severe enough to require hospitalization and blood transfusions. A 24 year old man was diagnosed with P. falciparum, prompting initiation of oral artemether-lumefantrine (AL). Further work-up demonstrated that he met WHO criteria for severe malaria infection on the basis of high parasitemia and his regimen was switched to intravenous quinidine and oral doxycycline. He was transitioned back to AL after 4 days and was discharged on hospital day six. Five days later, he was readmitted for hemolytic anemia. His peripheral blood was absent of malaria parasites and he was diagnosed with PADH, ultimately requiring multiple blood transfusions. Severe hemolytic anemia requiring blood transfusions after oral artemisinin therapy is rare and may be associated with higher parasite loads. This case demonstrates the importance of close reassessment and consideration of PADH in patients treated with oral therapies, particularly in the setting of severe malarial infections.

Delayed Hemolytic Anemia after Treatment with Artesunate: Case Report and Literature Review

BACKGROUND

In recent years, few cases of post-artemisinin delayed hemolysis have been reported.

OBJECTIVE

All cases of post-artemisinin delayed hemolysis were reported from non-middle east areas. No case of post-artemisinin delayed hemolysis has yet been reported from this region. In this paper, we describe a case of post-artemisinin delayed hemolysis in an Iranian female. Moreover, previous reports have been reviewed.

METHODS

Patient's data including demographic characteristics, past medical, drug and travelling history, present illness, vital signs, laboratory data, clinical course of current illness and follow-up findings were considered.

RESULTS

A 27-year-old female with a recent travel history to Ghana admitted with severe falciparum malaria. She was successfully treated with parenteral artesunate. However after 12 days of post artesunate treatment, she returned with dark urine, malaise and fatigue.

CONCLUSION

Considering the clinical course and base on a reliable causality assessment scale, post artesunate delay hemolytic anemia was possible.

Optimization and evaluation of lipid emulsions for intravenous co-delivery of artemether and lumefantrine in severe malaria treatment

Parenteral therapy for severe and complicated malaria is necessary, but currently available parenteral antimalarials have their own drawbacks. As for recommended artemisinin-based combination therapy, antimalarial artemether and lumefantrine are limited in parenteral delivery due to their poor water solubility. Herein, the aim of this study was to develop the lipid-based emulsions for intravenous co-delivery of artemether and lumefantrine. The lipid emulsion was prepared by high-speed shear and high-pressure homogenization, and the formulations were optimized mainly by monitoring particle size distribution under autoclaved conditions. The final optimal formulation was with uniform particle size distribution (~ 220 nm), high encapsulation efficiency (~ 99%), good physiochemical stability, and acceptable hemolysis potential. The pharmacokinetic study in rats showed that C_max of artemether and lumefantrine for the optimized lipid emulsions were significantly increased than the injectable solution, which was critical for rapid antimalarial activity. Furthermore, the AUC_0-t of artemether and lumefantrine in the lipid emulsion group were 5.01- and 1.39-fold of those from the solution, respectively, suggesting enhanced bioavailability. With these findings, the developed lipid emulsion is a promising alternative parenteral therapy for the malaria treatment, especially for severe or complicated malaria.

Retrospective observational study of the use of artemether-lumefantrine in the treatment of malaria in Japan

BACKGROUND

The Research Group on Chemotherapy of Tropical Diseases, Japan, introduced artemether-lumefantrine (AL) in late 2002, mainly for treating uncomplicated Plasmodium falciparum malaria. Because AL was on the market in Japan in March 2017, the effectiveness and safety of AL were analyzed to help medical personnel use AL optimally.

METHODS

Case report forms submitted by the attending physicians were analyzed. When necessary, direct contact with the attending physicians was made to obtain detailed information.

RESULTS

Effectiveness analysis was performed for 62 cases and safety analysis was performed for 66 cases. In P. falciparum malaria, the overall cure rate was 91.1% (51/56), of which the cure rates for Japanese and non-Japanese patients were 82.1% (23/28) and 100% (28/28), respectively. The successfully treated cases included severe P. falciparum malaria, with parasite densities exceeding 500,000/μL. Adverse events were reported in 14 patients, including delayed hemolytic anemia which occurred in the top four highest parasitemic cases.

CONCLUSIONS

AL treatment failure in P. falciparum malaria may not be rare among non-immune individuals, including Japanese. The possibility of delayed hemolytic anemia, which occurs preferentially in high parasitemic cases, should be considered following AL treatment.

Hemolysis after Oral Artemisinin Combination Therapy for Uncomplicated Plasmodium falciparum Malaria

Episodes of delayed hemolysis 2-6 weeks after treatment of severe malaria with intravenous artesunate have been described. We performed a prospective observational study of patients with uncomplicated malaria to investigate whether posttreatment hemolysis also occurs after oral artemisinin-based combination therapy. Eight of 20 patients with uncomplicated malaria who were given oral artemisinin-based combination therapy met the definition of posttreatment hemolysis (low haptoglobin level and increased lactate dehydrogenase level on day 14). Five patients had hemolysis persisting for 1 month. Patients with posttreatment hemolysis had a median decrease in hemoglobin level of 1.3 g/dL (interquartile range 0.3-2.0 g/dL) in the posttreatment period, and patients without posttreatment hemolysis had a median increase of 0.3 g/dL (IQR -0.1 to 0.7 g/dL; p = 0.002). These findings indicate a need for increased vigilance for hemolytic events in malaria patients, particularly those with predisposing factors for anemia.

Severe delayed haemolytic anaemia associated with artemether-lumefantrine treatment of malaria in a Japanese traveller

Delayed haemolytic anaemia has been reported in association with intravenous artesunate treatment in patients with severe Plasmodium falciparum malaria, and furthermore, oral artemisinin-based combination therapies including artemether-lumefantrine (AL) have also been incriminated. However, definite cases of delayed haemolytic anaemia associated with AL appear to be scarce, as reported cases were often treated concomitantly with other anti-malarials. In this study, we report a severe case of delayed haemolytic anaemia following AL alone in a Japanese traveller with severe parasitaemia caused by numerous P. falciparum parasites and a few P. vivax parasites. We also stress the need by further studies to differentiate between delayed haemolytic anaemia and blackwater fever, the latter being another malaria-related haemolytic condition, more clearly than they are now.

Artesunate to treat severe malaria in travellers: review of efficacy and safety and practical implications

BACKGROUND

Artesunate (AS) is the WHO first-line treatment of severe malaria in endemic countries, in adults and children. However, despite solid evidence that AS is safe and more effective than quinine in endemic areas, its deployment in non-endemic areas has been slow, due in part to the absence of a full good manufacturing practice (GMP) qualification (although prequalification has been granted in 2010). Prospective comparative trials were not conducted in travellers, but several retrospective studies and case reports are providing insights into the efficacy and safety of AS in imported severe malaria.

METHODS

We performed a systematic review on AS use in non-endemic areas for the treatment of imported severe malaria, using the Prisma method for bibliographic reports. Post-AS delayed haemolysis (PADH) was defined by delayed haemolytic episodes occurring 7-30 days after treatment initiation. We summarized prescription guidelines and generated answers to frequently asked questions regarding the use of AS in travellers with severe malaria.

RESULTS

We analysed 12 retrospectives and 1 prospective study as well as 7 case reports of AS treatment in 624 travellers. Of 574 patients with reported outcome, 23 died (4%). No death was attributed to AS toxicity. Non-haematological side effects were uncommon and mainly included mild hepatitis, neurological, renal, cutaneous and cardiac manifestations. PADH occurred in 15% of the treated patients. No death or sequelae were reported. Overall blood transfusion was administered in 50% of travellers with PADH.

CONCLUSION

AS is highly efficacious in travellers with severe malaria. The frequency of PADH supports the need of weekly follow-up of haematological parameters during 1 month. Full GMP qualification for the drug and rapid approval by drug agencies is warranted, backed by clear recommendations for optimal use.

Development of Delayed Hemolytic Anemia After Treatment with Oral Artemether-Lumefantrine in Two Patients with Severe Falciparum Malaria

AbstractRecently, reports of delayed hemolytic anemia after treatment with artemisinin and its derivatives have emerged. Here we report two cases of delayed hemolytic anemia in a patient with severe falciparum malaria after treatment with oral artemether-lumefantrine (AL). The first patient, a 20-year-old Japanese male student, was diagnosed with falciparum malaria and was administered AL. As having a high parasitemia rate (20.6%) was the only severe malaria criterion met in this case and his general condition was stable, we continued with AL treatment. Despite disappearance of malarial parasites after 4 days of AL administration, a persistent fever remained. On days 13 and 16, a diagnosis of hemolytic anemia was made (lactate dehydrogenase [LDH]: 1,466 U/L, hemoglobin [Hb]: 7.2 g/dL). A blood smear at that time revealed no parasites. He recovered naturally from delayed hemolysis. The second patient, a 27-year-old Japanese female student, was diagnosed with falciparum malaria (parasitemia: 4.5%) and treated initially with oral quinine hydrochloride and doxycycline. The following day, parasitemia increased to 7.9% and oral AL was initiated. She was discharged on day 4 after achieving parasite clearance and afebrility. However, on day 5, fever (body temperature > 38°C) recurred, and on day 11, a diagnosis of hemolytic anemia was made (LDH: 712 U/L, Hb: 8.8 g/dL). A follow-up confirmed that her condition improved gradually. AL treatment of severe malaria can cause delayed hemolytic anemia. Patients should be followed up for up to 4 weeks to detect signs of hemolysis and provide appropriate symptomatic treatment.

Severe malaria in Europe: an 8-year multi-centre observational study

Background

Malaria remains one of the most serious infections for travellers to tropical countries. Due to the lack of harmonized guidelines a large variety of treatment regimens is used in Europe to treat severe malaria.

Methods

The European Network for Tropical Medicine and Travel Health (TropNet) conducted an 8-year, multicentre, observational study to analyse epidemiology, treatment practices and outcomes of severe malaria in its member sites across Europe. Physicians at participating TropNet centres were asked to report pseudonymized retrospective data from all patients treated at their centre for microscopically confirmed severe Plasmodium falciparum malaria according to the 2006 WHO criteria.

Results

From 2006 to 2014 a total of 185 patients with severe malaria treated in 12 European countries were included. Three patients died, resulting in a 28-day survival rate of 98.4%. The majority of infections were acquired in West Africa (109/185, 59%). The proportion of patients treated with intravenous artesunate increased from 27% in 2006 to 60% in 2013. Altogether, 56 different combinations of intravenous and oral drugs were used across 28 study centres. The risk of acute renal failure (36 vs 17% p = 0.04) or cerebral malaria (54 vs 20%, p = 0.001) was significantly higher in patients ≥60 years than in younger patients. Respiratory distress with the need for mechanical ventilation was significantly associated with the risk of death in the study population (13 vs 0%, p = 0.001). Post-artemisinin delayed haemolysis was reported in 19/70 (27%) patients treated with intravenous artesunate.

Conclusion

The majority of patients with severe malaria in this study were tourists or migrants acquiring the infection in West Africa. Intravenous artesunate is increasingly used for treatment of severe malaria in many European treatment centres and can be given safely to European patients with severe malaria. Patients treated with intravenous artesunate should be followed up to detect and manage late haemolytic events.

Evidencing the Role of Erythrocytic Apoptosis in Malarial Anemia

In the last decade it has become clear that, similarly to nucleated cells, enucleated red blood cells (RBCs) are susceptible to programmed apoptotic cell death. Erythrocytic apoptosis seems to play a role in physiological clearance of aged RBCs, but it may also be implicated in anemia of different etiological sources including drug therapy and infectious diseases. In malaria, severe anemia is a common complication leading to death of children and pregnant women living in malaria-endemic regions of Africa. The pathogenesis of malarial anemia is multifactorial and involves both ineffective production of RBCs by the bone marrow and premature elimination of non-parasitized RBCs, phenomena potentially associated with apoptosis. In the present overview, we discuss evidences associating erythrocytic apoptosis with the pathogenesis of severe malarial anemia, as well as with regulation of parasite clearance in malaria. Efforts to understand the role of erythrocytic apoptosis in malarial anemia can help to identify potential targets for therapeutic intervention based on apoptotic pathways and consequently, mitigate the harmful impact of malaria in global public health.

Delayed Hemolysis After Parenteral Artesunate Therapy for Severe Malaria in Two Returning Canadian Travelers

Delayed hemolysis after parenteral artesunate has been described in Europe and Asia, but until recently had not been reported in patients receiving the artesunate product used in the United States and Canada. We report two cases of severe delayed hemolysis after the treatment with intravenous artesunate in Canada.

Severe falciparum malaria treated with artesunate complicated by delayed onset haemolysis and acute kidney injury

Background

Severe falciparum malaria may be complicated by haemolysis after parasite clearance, however the mechanisms remain unclear. Recent reports describe a pattern of delayed onset haemolysis among non-immune travellers with hyperparasitaemia treated with intravenous artesunate, termed post-artesunate delayed haemolysis (PADH). The occurrence and clinical impact of PADH following severe malaria infections in areas of unstable transmission are unknown.

Case

A 45-year-old Bangladeshi male was initially admitted to a local hospital with severe falciparum malaria complicated by hyperparasitaemia and treated with intravenous artesunate. Twenty days from his first presentation he was readmitted with delayed onset haemolytic anaemia and acute kidney injury. Multiple blood transfusions and haemodialysis were required. Renal biopsy revealed acute tubular injury and haem pigment nephropathy. His haemoglobin and renal function recovered to baseline after 62 days from his second admission.

Discussion

This case highlights the differential diagnosis of post-malaria delayed onset haemolysis, including the recently described syndrome of post-artemisinin delayed haemolysis. The pathophysiology contributing to acute kidney injury in this patient and the limited treatment options are discussed.

Conclusions

This report describes PADH complicated by acute kidney injury in an adult patient living in a malaria hypoendemic region who subsequently required blood transfusions and haemodialysis. This case emphasizes the importance of routine follow up of haemoglobin and renal function in artesunate-treated patients who have recovered from severe malaria.

Haemolysis associated with the treatment of malaria with artemisinin derivatives: a systematic review of current evidence

BACKGROUND

Artemisinin derivatives are the mainstay of antimalarial treatment, both for uncomplicated malaria and for severe disease. Artemisinins are known for their rapid onset of action, good tolerability, and safety. However, besides the sporadic but worrying reports of delayed parasite clearance after treatment with artemisinins, there have been an increasing number of reports of acute haemolytic anaemia following their use and the safety of this class of antimalarials is being questioned.

METHODS

In this systematic review, all reports of patients experiencing haemolysis following the use of artemisinins for the treatment of malaria were identified and collated into an electronic database. Summary statistics were calculated to characterize the epidemiology and clinical features of this safety concern related to artemisinin derivatives.

RESULTS

A total of 37 patients were identified suffering from haemolysis following the treatment of severe malaria with artemisinin derivatives. Thirty-one cases had received intravenous artesunate, while the remaining cases were attributed to other parenteral or oral regimens of artemisinin derivatives. The majority of patients were returning travellers (n=30), and six clinical cases had been reported in paediatric patients. The median onset of haemolysis was 15 (interquartile range (IQR) 13-15) days after the initiation of treatment for the 'delayed-onset' pattern and 17 (IQR 13-22) days for the 'persistent' haemolysis pattern. The median reduction in haemoglobin due to haemolysis was 6 g/dl (IQR 4-8 g/dl). The estimated proportion of patients suffering from severe malaria experiencing haemolysis after treatment with artemisinin derivatives was 13% (95% confidence interval 9-18%), and 73% of these (i.e., 9% of the total population) required blood transfusions. No fatal outcome has been reported in the literature to date.

CONCLUSIONS

Haemolysis is commonly associated with the class of artemisinin drugs when used for the treatment of severe malaria. Potential causes of this safety issue are discussed. Although no deaths attributed to haemolysis have been reported so far, this safety issue may lead to life-threatening anaemia and is particularly worrying for regions where safe blood products are not readily available.

Delayed anemia assessment in patients treated with oral artemisinin derivatives for uncomplicated malaria: a pooled analysis of clinical trials data from Mali

Background

In sub-Saharan Africa, artemisinin-based combination therapy (ACT) and injectable artesunate are the first-line treatments for uncomplicated and severe Plasmodium falciparum malaria, respectively. However, recent studies suggest that delayed anaemia is associated with these treatments in non-immune travellers. This paper aimed to assess the risk factors associated with delayed anaemia after falciparum malaria treatment with artemisinin-containing drugs in malaria-endemic populations.

Methods

Pooled, individual malaria patient data were extracted from 13 clinical trials performed from 2002 to 2011 in various settings of Mali. Treatment regimens were artemether-lumefantrine, artesunate plus amodiaquine, artesunate plus sulphadoxine-pyrimethamine, artesunate plus sulphamethoxypyrazine-pyrimethamine, artesunate plus mefloquine, artesunate-pyronaridine, artesunate monotherapy, chloroquine, sulphadoxine-pyrimethamine, amodiaquine and sulphadoxine-pyrimethamine plus amodiaquine. Univariate and multivariate analyses were performed using the generalized linear and latent mixed model procedures to assess risk factors associated with haemoglobin concentration evolution and anaemia during the treatment follow-up.

Results

A total of 5,990 participants were recruited and followed from day 0 to day 28. The participants’ median age was five years, ranging from three months to 70 years. There was a decrease in haemoglobin level on day 7 in all treatment arms, but the magnitude varied across treatments. There was a significant risk of haemoglobin level decrease on day 7 in the artemisinin-based therapy compared to the non-artemisinin treatments. The risk of haemoglobin concentration drop was associated with age group < five years old (0.61 g/dL 95% CI (0.71 to 0.51), p < 0.001), baseline high parasite density (0.43 g/dL 95% CI (0.51 to 0.35), p < 0.001) and treatment failure (0.40 g/dL 95% CI (0.59 to 0.20), p = 0.018), while high haemoglobin level at baseline was a protective factor (0.53 to 0.59) p < 0.001). No association was found between artemisinin-based therapy and severe delayed anaemia.

Conclusions

Oral artemisinin derivative treatments for uncomplicated P. falciparum malaria are associated with a transient and clinically moderate haemoglobin decrease by day 7 but not associated with a delayed severe anaemia.

Electronic supplementary material

The online version of this article (doi:10.1186/1475-2875-13-358) contains supplementary material, which is available to authorized users.

Extracorporeal membrane oxygenation for refractory acute respiratory distress syndrome in severe malaria

Background

Severe malaria may be complicated by the acute respiratory distress syndrome (ARDS), which is associated with a high mortality. In the present report, a series of three cases of imported malaria complicated by refractory severe ARDS supported with extracorporeal membrane oxygenation (ECMO) is presented.

Methods

One female and two male adult patients (ages 39 to 53) were included. Two patients had Plasmodium falciparum infection and one patient had Plasmodium vivax and Plasmodium ovale co-infection. Anti-malarial therapy consisted in intravenous quinine (in two patients) and intravenous quinidine (in one patient), plus clindamycin or doxycycline.

Results

Despite lung protective ventilation, a conservative strategy of fluid management, corticosteroids (two patients), prone position (two patients) and inhaled nitric oxide (one patient), refractory severe ARDS supervened (PaO₂ to FiO₂ ratio 68) and venovenous ECMO was then initiated. In one patient, a bicaval dual-lumen cannula was inserted; in the two other patients, a two-site configuration was used. Two patients survived to hospital-discharge (duration of ECMO support: 8.5 days) and one patient died from nosocomial sepsis and multi-organ failure after 40 days of ECMO support.

Conclusions

ECMO support allowed adequate oxygenation and correction of hypercapnia under lung protective ventilation, therefore reducing ventilator-induced lung injury. ECMO referral should be considered early in malaria complicated by severe ARDS refractory to conventional treatment.