Detection of protozoal parasites in the stools of diarrhoeic patients using different techniques

Area of Science:

• Medical Parasitology
• Diagnostic Microbiology
• Pediatric Infectious Diseases

Background:

• Enteric protozoa infections pose a significant global health burden, particularly in children.
• Accurate and sensitive diagnostic methods are crucial for effective treatment and control of parasitic infections.

Purpose of the Study:

• To compare the efficacy of direct wet smear microscopy with concentration and staining techniques for detecting enteric protozoa in children.
• To evaluate the sensitivity of different diagnostic methods for Giardia lamblia, Entamoeba histolytica, Entamoeba coli, and Cryptosporidium parvum.

Main Methods:

• A total of 180 apparently healthy children were included in the study.
• Stool samples were examined using direct wet smear, concentration-sedimentation, Sheather's concentration method, Modified Zeihl-Nelsen stain, Mallory, Iron haematoxylin, and Trichrome staining.
• Medical questionnaires were administered to assess child health status.

Main Results:

• Direct wet smear microscopy consistently detected lower infection percentages for all target protozoa compared to concentration and staining methods.
• Concentration methods showed higher detection rates for Giardia lamblia (11.0%, 10.3%), Entamoeba histolytica (3.3%, 3.7%), and Entamoeba coli (7.3%, 7.0%).
• Modified Zeihl-Nelsen stain identified 3.0% Cryptosporidium parvum infections, while Mallory and Iron haematoxylin stains provided good characteristic visualization.

Conclusions:

• Direct wet smear microscopy is less sensitive for detecting enteric protozoa in children.
• Concentration and specific staining techniques (Mallory, Iron haematoxylin, Trichrome, Modified Zeihl-Nelsen) are superior for accurate diagnosis.
• Improved diagnostic accuracy is essential for managing pediatric enteric protozoan infections effectively.