Prevalence of Intestinal Amebiasis Among Saudi Residents Living in the Al-Baha Region, Saudi Arabia

Entamoeba histolytica is a pathogenic protozoan parasite that can cause amoebiasis, which is one of the leading causes of death from parasitic infections.

This study aimed to estimate the prevalence of intestinal amebiasis among Saudi patients who attended the two major hospitals, including King Fahad Hospital in Al-Baha and Prince Meshari Hospital in Baljurashi, which is a big governorate in Al-Baha, in addition to the Central Laboratory in the Al-Baha region.

This is a retrospective study of demographic, clinical, radiological, and laboratory data collected from patients' records covering the period from January 2019 to December 2024.

Out of a total of 6,471 stool samples examined, 534 (8.25%) were positive for E. histolytica in the form of cysts or trophozoites. Of these positive cases, 305 (57.1%) occurred in males, while 229 (42.9%) were in females. The highest proportion of infections was detected among children aged 6-12 years, accounting for 173 cases (32.4%). In terms of geographic distribution, the majority of cases were recorded in Al-Baha city (296 cases; 55.4%), followed by Baljurashi (195 cases; 36.5%), with the lowest prevalence observed in being from Ghamed and Hajra governorates. Stool macroscopic examination findings included blood in stool in 76 (14.2%) samples of undigested food in 134 (25.1%) samples. Microscopy findings included cysts in 518 (97%) samples, trophozoites in 130 (24.3%), white blood cell (WBC) count of more than 76 cells/μL in (31.5%) 168 samples, and red blood cell (RBC) count of more than 26 cells/μL in 59 (11%) samples. Presence of blood in stool was strongly associated (p < 0.001) with trophozoite. Semi-formed, watery, and mucoid stools were significantly associated with trophozoites. Count of RBCs of >26 cells/μL was significantly (p < 0.001) associated with trophozoite infections. Colonoscopy findings were significantly (p < 0.001) associated with trophozoite cases. Radiological findings were significantly (p < 0.001) higher in trophozoite-positive cases, complications were significantly (p < 0.001) higher in trophozoite cases, and mean corpuscular volume (MCV) was significantly (p = 0.028) lower in cystic cases (75.68 ± 9.7) than in trophozoites (79.44 ± 7.51).

E. histolytica remains an important protozoan infection in Saudi Arabia, particularly among the age group of 6-12 years old. The predominance of the cystic form underscores the potential for transmission, and co-infections suggest gaps in sanitation infrastructure. Efforts are needed to evaluate the E. histolytica health burden in Al-Baha provinceto enhance the treatment of infected people at primary care centers and to reinforce hygiene.