title: Plasmodium vivax malaria: related factors to severity in the State of Maranhão, Brazil.
abstract: BACKGROUND
  Malaria caused by Plasmodium vivax species has shown signs of severity, recorded with increasing frequency in the medical literature. This study aimed to characterize the signs of severe malaria by Plasmodium vivax in the State of Maranhão, Brazil.
  
  
  METHODS
  A descriptive cohort study of patients assisted in the field and a historical and concurrent study of a series of cases among hospitalized patients were undertaken to identify the clinical and laboratory signs of severity.
  
  
  RESULTS
  A total of 153 patients were included in the study, 13 of whom were hospitalized. Males made up the majority, numbering 103 (67.3%). The age of the patients ranged from 10 to 70 years, 92.2% were natives of the State of Maranhão, and 65% of the patients had had malaria before. The average time elapsed between symptom onset and diagnosis among outpatients was three days, while among hospitalized patients this average reached 15.5 days, a statistically significant difference (p=0.001). The parasitemia ranged from 500 to 10,000 parasites/µl in 92.8% of cases. The clinical and laboratory manifestations of severity were vomiting and diarrhea, jaundice, drowsiness, mental confusion, seizures, loss of consciousness, agitation, bleeding, pale skin, coughing and dyspnea, thrombocytopenia, anemia, elevation of nitrogenous compounds, and elevated transaminases and bilirubin.
  
  
  CONCLUSIONS
  The monitoring of malaria patients with Plasmodium vivax showed the possibility of aggravation, the intensity of which varied in different circumstances, especially the interval time between falling ill and diagnostic confirmation.
authors.affiliation: Centro de Referência em Doenças Infecciosas e Parasitárias, Departamento de Patologia, Universidade Federal do Maranhão, São Luis, MA, Brasil.
authors.forename: Camila Cristina Bastos Silva
authors.initials: CC
authors.lastname: Raposo
authors.forename: João Barberino
authors.initials: JB
authors.lastname: Santos
authors.forename: Gisele Maria Campelo dos
authors.initials: GM
authors.lastname: Santos
authors.forename: Eloísa da Graça do Rosário
authors.initials: Eda G
authors.lastname: Gonçalves
authors.forename: Antonio Rafael da
authors.initials: AR
authors.lastname: Silva
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001938:Brazil / Q000453:epidemiology; D002648:Child; D005260:Female; D006801:Humans; D016780:Malaria, Vivax / Q000150:complications* / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D018512:Parasitemia / Q000469:parasitology; D012307:Risk Factors; D012720:Severity of Illness Index; D055815:Young Adult