Physiopathology and clinical management of blackwater fever: a scoping review

BACKGROUND

Blackwater fever (BWF) is a severe syndrome occurring in patients with malaria upon antimalarial treatment, characterized by massive intravascular haemolysis and haemoglobinuria. BWF is a neglected condition and management recommendations are unavailable.

OBJECTIVES

We performed a scoping review to appraise available data on clinical picture, treatment and physiopathology of BWF, which could guide rationally its clinical management.

METHODS

MEDLINE, EMBASE, LILACS, Web of Science, and Scopus databases, and the reference list of relevant publications, were searched. Papers reporting original data on BWF cases or investigating the physiopathology of BWF were eligible. Data regarding case characteristics, trigger event, clinical management and outcome were extracted. For papers investigating the physiopathology of BWF, study design and principal findings were extracted. No quality assessment was performed. Data are presented as numbers and percentages, and summary of findings, grouped by paper focus (clinical description or physiopathology).

RESULTS

101 papers were included. The majority of BWF cases were observed in autochthonous children (75.7%) and adults (15.3%), in contrast with historical perception that BWF patients were typically expatriates. Clinical management was described for 794 cases; corticosteroids were used in 23. Outcome was reported for 535 patients, with 18.1% mortality. The trigger was reported for 552 (47.5%) cases; in 70.4% identified as quinine. However, two RCT comparing artesunate and quinine for falciparum malaria treatment did not find significant difference in BWF occurrence after their administration. Two case-control studies did not find significant difference in G6PDH deficiency between malaria patients with and without BWF.

CONCLUSIONS

The physiopathology and optimal treatment of BWF remain similarly unknown as they were over a century ago. Empirical supporting treatment approach seems reasonable, while change of antimalarial drug and use of corticosteroids remain object of debate.

A MINI OVERVIEW OF MALARIA IN PREGNANCY

Human malaria is caused by five species of Plasmodia: P. falciparum, P. vivax, P. ovale, P. malariae and P. knowlesi. Most infections are due to either P. falciparum or P. vivax, but mixed infections with more than one malarial species also occur. The majority of malaria-related deaths are due to P. falciparum. Generally, the pregnant women are a high risk group, as malaria can be a life threatening infection for both mother and fetus. Risk of stillbirth, spontaneous abortion, and other adverse pregnancy outcomes is increased in the setting of malaria, and pregnant travelers should be advised to defer travel until after delivery whenever feasible.

Blackwater fever in children, Burundi

Blackwater fever is characterized by acute intravascular hemolysis with hemoglobinuria in patients with Plasmodium falciparum malaria. Its pathogenesis and management are still debated. Nine cases of this syndrome occurred in 2003 at Kiremba Hospital in Burundi in children receiving multiple quinine treatments.

Epidemiological and clinical aspects of blackwater fever among African children suffering frequent malaria attacks

Blackwater fever (BWF), one of the commonest causes of death of Europeans living in Africa at the beginning of the twentieth century, but rarely diagnosed since the 1950s, is related to Plasmodium falciparum malaria but there is considerable debate and controversy about its aetiology. From 1990 to 2000, the whole population of Dielmo, a village in Senegal, was involved in a prospective study of malaria. Three cases of BWF occurred in 3 children aged 4, 7 and 10 years, belonging to a subgroup of children who suffered malaria attacks every 4 to 6 weeks over many years, who had received repeated quinine treatment. The spread of chloroquine resistance, by increasing the use of more toxic alternative drugs, may expose endemic populations to a high incidence of severe side effects of antimalarials.

[Blackwater fever during antimalarial treatment in Abidjan (West Africa): report of 41 cases]

Intravascular haemolysis, particularly blackwater fever is a rare but severe clinical syndrome, occurring after ingestion of antimalarials. A resurgence of this affection which occurred frequently during the colonization has lately been noticed. We have conducted a prospective study in order to identify the main antimalarials which are responsible for this syndrome. We reported 41 cases from 1996 to 2000, among which 80% of blackwater fever cases were associated with quinine ingestion or similar structural molecules. Their causal role is well established. For the other molecules it is difficult to underscore their role. The mortality rate is around 18%. The morbidity is high because 90% of patients have suffered from renal failure. Among them, 47% required dialysis. We are facing a public health issue thus a rational use of antimalarials is necessary.

Resurgence of blackwater fever in long-term European expatriates in Africa: report of 21 cases and review

Blackwater fever (BWF) is a severe clinical syndrome, characterized by intravascular hemolysis, hemoglobinuria, and acute renal failure that is classically seen in European expatriates chronically exposed to Plasmodium falciparum and irregularly taking quinine. BWF virtually disappeared after 1950, when chloroquine superseded quinine. We report 21 cases of BWF seen in France from 1990 through 1999 in European expatriates who lived in sub-Saharan Africa. All patients had macroscopic hemoglobinuria, jaundice, and anemia. Acute renal failure occurred in 15 patients (71%), 7 of whom required dialysis. The presumed triggers of BWF were halofantrine (38%), quinine (24%), mefloquine (24%), and halofantrine or quinine (14%). Glucose-6-phosphate dehydrogenase (G6PD) activity was normal in the 14 patients who underwent this test. Low-level P. falciparum parasitemia was found in 8 patients. All 21 patients survived. Our data and 13 cases reported in the literature suggest a resurgence of classic BWF among Europeans living in Africa and a need to discuss attendant therapeutic implications.

Blackwater fever in southern Vietnam: a prospective descriptive study of 50 cases

We prospectively studied 50 Vietnamese patients with blackwater fever (BWF). All patients had fever and hemoglobinuria, 40 (80%) were jaundiced, 25 (50%) had hepatomegaly, 15 (34%) had splenomegaly, and 9 (18%) had hepatosplenomegaly. Twenty-one patients (42%) had impaired renal function, with creatinine clearances of < 50 mL/min/m2; however, only four (8%) developed oliguric renal failure, three (6%) of whom required dialysis. Forty-four patients (88%) developed anemia, which was severe (hematocrit, < 20% in 32 (64%). One patient died, representing a death rate for this once-feared disease that is considerably lower than that reported by earlier investigators. BWF was associated with quinine ingestion in 28 patients (56%), glucose-6-phosphate dehydrogenase (G6PD) deficiency in 27 (54%), and concurrent malaria infection in 16 (32%). There was no statistically significant difference in the severity of BWF associated with each of these three factors, as assessed by creatinine clearance and the hematocrit value on admission and by the number of units of blood transfused. There was considerable overlap in the occurrence of G6PD deficiency, quinine ingestion, and malaria, suggesting that these factors may interact and that it may not be justifiable to regard hemoglobinuria caused by G6PD deficiency as a separate syndrome.