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

## TL;DR

This study finds that intestinal amebiasis caused by Entamoeba histolytica is prevalent in Saudi Arabia's Al-Baha region, especially among children aged 6-12.

## Contribution

The study provides new prevalence data for E. histolytica in the Al-Baha region and identifies risk factors and clinical associations.

## Key findings

- 8.25% of 6,471 stool samples tested positive for E. histolytica, with children aged 6-12 years being the most affected group.
- Cysts were the most common form detected (97%), and trophozoite presence was strongly associated with blood in stool and radiological complications.
- Al-Baha city had the highest infection rate, suggesting localized transmission and sanitation challenges.

## Abstract

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

Aims: 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.

Methods: 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.

Results: 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).

Conclusions: 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.