RESUMO
The chemosusceptibility and genetic polymorphism of Plasmodium falciparum populations from 48 patients hospitalized for malaria at the Hospital Principal in Dakar, Senegal were investigated during the 2002 malaria transmission season. Sixty-two percent of the isolates collected were from patients with severe malaria and 38% were from patients with mild malaria. In vitro activities of chloroquine, quinine, cycloguanil, atovaquone, mefloquine, halofantrine, and artesunate were evaluated. The prevalence of mutations in the Plasmodium falciparum dihydrofolate reductase (dhfr) and dihyropteroate synthetase (dhps) genes and the P. falciparum chloroquine resistance transporter (Pfcrt) gene associated with cycloguanil, pyrimethamine, sulfadoxine, and chloroquine resistance were estimated. The genetic polymorphism of the parasite populations was evaluated by analysis of the highly polymorphic regions of merozoite surface protein 1 (msp1) block 2 and msp2. Seventy percent of the isolates were assessed by an in vitro assay. Fifty-two percent of the isolates were chloroquine resistant, 45% were cycloguanil resistant, and 24% were atovaquone resistant. Four percent had low susceptibility to quinine. The Pfcrt and dhfr mutations were associated with in vitro chloroquine- and antimetabolic drug-resistant isolates, respectively. Approximately 70% of the isolates contained two or more clones. Genetic diversity of P. falciparum was high. The prevalence of allelic family K1 of msp1 was 68%. Isolates of P. falciparum were highly resistant to chloroquine, cycloguanil and atovaquone. The transmission rate of malaria in Dakar is low but a high degree of genetic polymorphism can increase severe malaria, as shown by persons coming to Dakar from areas highly endemic for malaria. Areas with urban malaria should use vector control measures and efficient chemoprophylaxis for non-immune populations.
Assuntos
Antimaláricos/farmacologia , Malária Falciparum/parasitologia , Plasmodium falciparum/efeitos dos fármacos , Plasmodium falciparum/genética , Polimorfismo Genético , População Urbana , Adolescente , Adulto , Idoso , Animais , Antígenos de Protozoários/genética , Criança , Pré-Escolar , Di-Hidropteroato Sintase/genética , Feminino , Frequência do Gene , Humanos , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana Transportadoras , Proteína 1 de Superfície de Merozoito/genética , Pessoa de Meia-Idade , Testes de Sensibilidade Parasitária/métodos , Proteínas de Protozoários/genética , SenegalRESUMO
BACKGROUND AND PURPOSE: Basic stroke features are hardly known in sub-Saharan countries, and no data are available in Senegal. METHODS: We performed a retrospective hospital-based study in Dakar, Senegal, to assess risk factors and etiology of stroke. Patients were recruited from January 1, 2003, to July 31, 2004, at the Hôpital Principal, Dakar. Strokes had to be ascertained by computed tomography. RESULTS: A total of 107 patients were studied. Seventy percent of strokes were of ischemic nature. For ischemic strokes, mean age was 64.2 years. Hypertension was the main risk factor, occurring in 68%, and diabetes was encountered in 37.3%. Lacunar strokes and cardioembolism accounted for 20% and 13.3%, respectively. Because of the lack of systematic investigations, two thirds of strokes were of undetermined origin. Mortality within 1 month was 38%. For hemorrhagic strokes, mean age was 51 years and 1 month mortality was 56%. CONCLUSIONS: Hypertension is the main risk factor for both ischemic and hemorrhagic strokes in this hospital-based study.