Decreased hemoglobin concentrations, hyperparasitemia, and severe malaria are associated with increased Plasmodium falciparum gametocyte carriage.
To determine factors influencing gametocyte carriage, a cross-sectional study was conducted among 512 patients admitted for Plasmodium falciparum malaria. After adjustments for potential confounders, hemoglobin concentrations were lower in gametocyte carriers 10.5 (+/-2.5) than in patients without gametocytes 12.5 (+/-2.3) (P < 0.0001). Hemoglobin concentrations were negatively correlated with peak gametocyte counts (Spearman's p = -0.37, P < 0.0001) and gametocyte carriage durations (Spearman's p = -(0.30, P < 0.0001). Adjustments for the duration of the malaria episode and other potential confounders did not alter the association (P < 0.0001). After adjustment for potential confounders, the median asexual parasitemia was higher in patients with gametocytes than in patients without gametocytes (P = 0.003). Severe malaria cases were more likely to have gametocytes (65%) than malaria with hyperparasitemia (38%) or mild malaria (31%) (P = 0.0001). These findings suggest that events surrounding anemia and tissue hypoxia stimulate Plasmodium falciparum gametocytogenesis.
Nacher
Mathieu
M
Unité INSERM 511, Immunobiologie Cellulaire et Moléculaire des Infections Parasitaires, Faculté de médecine Pitié-Salpétrière, Paris, France. m_nacher@lycos.com
Singhasivanon
Pratap
P
Silachamroon
Udomsak
U
Treeprasertsuk
Sombat
S
Tosukhowong
Thanawat
T
Vannaphan
Suparp
S
Gay
Frédérick
F
Mazier
Dominique
D
Looareesuwan
Sornchai
S
D000293:Adolescent; D000328:Adult; D000368:Aged; D000818:Animals; D002353:Carrier State / Q000469:parasitology*; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005260:Female; D006454:Hemoglobins / Q000032:analysis*; D006801:Humans; D016778:Malaria, Falciparum / Q000097:blood / Q000469:parasitology / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D018512:Parasitemia / Q000469:parasitology*; D010963:Plasmodium falciparum / Q000302:isolation & purification* / Q000502:physiology; D012720:Severity of Illness Index
D006454:Hemoglobins