Quinine for the treatment of chloroquine-resistant Plasmodium falciparum malaria in pregnant and non-pregnant Sudanese women

Pregnant women are particularly susceptible to malaria, a disease that may have significant adverse effects on both the mother and the foetus (McGregor et al., 1983; McGregor, 1984). It is therefore important that pregnant women infected with malarial parasites receive prompt treatment with an effective and safe antimalarial drug or drug combination (WHO, 1986). Unfortunately, effective chemotherapy is being hampered by the spread of multidrug-resistant Plasmodium falciparum (White, 1992), by the relatively poor efficacy of several antimalarial drugs in the treatment of primigravidae (compared with that in non-pregnant women), and the fact that placental parasites tend to appear more resistant to the drugs than the parasites forming the peripheral parasitaemia (Steketee et al., 1987; Keuter et al., 1994; Sartelet et al., 1997). The emergence of resistance to quinine in P. falciparum, and a general lack of data on the effectiveness of this and other antimalarial drugs in the treatment of P. falciparum malaria during pregnancy (because pregnant women are usually excluded from clinical trials) have led to concern that the number of effective, proven treatment options for pregnant women infected with P. falciparum may be dwindling (McGready et al., 1998, 2000). The aim of the present, prospective, clinical trial, which was based in the New Halfa teaching hospital (NHTH) in eastern Sudan, was to evaluate and compare the efficacy of quinine in the treatment of pregnant and non-pregnant women with chloroquine-resistant malaria. Eastern Sudan is characterized by a low intensity of malaria transmission (Al Gadal, 1986). All the women (pregnant and nonpregnant) who, between November 2002 and March 2003, presented at the NHTH with P. falciparum malaria after a full course (five injections or 10 tablets) of chloroquine were invited to participate in clinical trials of quinine. Any women who declined to give verbal consent and those with severe malaria (WHO, 2000) were excluded. The pregnant women enrolled were alternately allocated to receive the full standard dose of quinine or a low-dose quinine regimen (Adam et al., 2004). The pregnant women who received the full standard dose and the non-pregnant women (all of whom received the standard dose) were the subjects of the present study. Each subject was given a physical examination on presentation, and the results of this examination were recorded, along with the socio–demographic characteristics, medical and obstetric histories of the subjects. Fingerprick samples of blood were collected immediately before quinine treatment (on day 0), then every 8 h until two consecutive bloodsmears were negative, then daily until day 7, and again on days 14, 21 and 28. Thick smears prepared from these samples were Giemsa-stained and examined under a light microscope. Levels of parasitaemia (asexual stages/ml) were estimated from these smears, by counting asexual malarial parasites against 200 leucocytes and assuming that each patient had 6000 leucocytes/ml. Haemoglobin concentrations were estimated on presentation, and capillary-blood glucose concentrations were estimated on presentation and every 2 h following the first dose of quinine. A subject Annals of Tropical Medicine & Parasitology, Vol. 99, No. 4, 427–429 (2005)