To investigate the seroprevalence and associated risk factors of entamoeba histolytica among patients with gastrointestinal complaints, and to measure the eventual changes in serum biochemical parameters to reflect its pathogenicity.The cross-sectional study was conducted in different hospitals of Potohar region in Punjab province and in the Khyber Pakhtunkhwa province of Pakistan from September 2015 to February 2017, and comprised individuals of either gender belonging to diverse backgrounds, inhabiting different areas of the country. The patients were enrolled from among those who visited outpatient departments with complaints of vague abdominal pain, nausea, vomiting, indigestion and diarrhoea. Blood samples were screened by using enzyme-linked immunosorbent assay and serum biochemical tests. Data was analysed using SPSS 20.Of the 356 subjects, 238(66.9%) were females and 118 (33.1%) were males. The overall mean age was 33.4}11.05 years. Seroprevalence of entamoeba histolytica was 356(73%). The infection rate did not differ significantly (p>0.05) among cities, while the highest infection was recorded in Islamabad 91(25.5%). The participants in rural areas had 2.16-fold higher risk of infection compared to urban areas, while the lowest risk of infection among people aged 50years compared to those aged 40-49 years (p=0.04). The amoebiasis was significantly associated with eating unwashed raw vegetables and average toilet facilities. Among clinical complications, haemodynamic changes, jaundice, vomiting, haemoglobin level, loose motion, intolerance to oral feeding, and history of antibiotics were significant associated variables (p<0.05 each). Significant elevation in alkaline phosphatase, aspartate aminotransferase, total protein and globulin levels were positively associated with amoebiasis (p<0.01 each).In entamoeba histolytica -positive patients ,serum biochemical level was found elevated and the risk factors determined were eating unwashed vegetables, toilet facilities, age, locality, jaundice, vomiting, haemoglobin level, loose motion, intolerance to oral feeding, and history of antibiotics.
