High occurrence of Entamoeba histolytica in the municipalities of Ariquemes and Monte Negro, State of Rondônia, Western Amazonia, Brazil

• Published in: Revista do Instituto de Medicina Tropical de São Paulo 2013-06, Vol.55 (3), p.193-196
• Main Authors: Santos, Rafael Vital dos, Nunes, Jucélia da Silva, Camargo, Juliana Almeida de Souza Aranha, Rocha, Eliana Maria Maurício da, Fontes, Gilberto, Camargo, Luís Marcelo Aranha
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Aged; Amazônia; Antigens, Protozoan - immunology; Brazil - epidemiology; Child; Child, Preschool; ELISA; Entamoeba histolytica; Entamoeba histolytica - immunology; Entamoeba histolytica - isolation & purification; Entamoebiasis - diagnosis; Entamoebiasis - epidemiology; Enzyme-Linked Immunosorbent Assay; Feces - parasitology; Female; Humans; Infant; Infant, Newborn; Male; Middle Aged; Prevalence; Risk Factors; Rondônia; TROPICAL MEDICINE; Urban Population; Young Adult
• ISSN: 0036-4665; 1678-9946; 1678-9946; 0036-4665
• DOI: 10.1590/S0036-46652013000300010

Entamoeba histolytica infections were investigated in residents of the Ariquemes and Monte Negro municipalities in Rondônia State, Brazil. Stool samples of 216 individuals were processed by the spontaneous sedimentation method and analyzed by microscopy for detection of the E. histolytica/E. dispar complex, followed by the immunoassay method using an enzyme-linked immunosorbent assay-based kit for the E. histolytica stool antigen. E. histolytica/E. dispar cysts were present in 61% (50/82) and 44% (59/134) of the samples from Ariquemes and Monte Negro respectively, with a significant difference in the occurrence of infection between the two populations [p < 0.05; χ2 = 5.2; odds ratio = 2.0 (1.1 - 3.6)]. The E. histolytica antigen detection rate was 36.6% (30/82) for stool samples from Ariquemes, and 19.4% (26/134) for stool taken from the residents of Monte Negro. The rate of the occurrence of amoebiasis was significantly higher in the population from Ariquemes [p < 0.05; χ2 = 7.8; odds ratio = 2.4 (1.2 - 4.7)]. Due to the high occurrence of E. histolytica infected residents diagnosed in the region and the unavailability in local clinics of a test to distinguish between the two Entamoeba species, physicians should consider treating E. histolytica/E.dispar infections. The results indicate that E. histolytica infection is highly endemic in the studied areas.