Is intestinal parasitic infection still a public health concern among Saudi children?

OBJECTIVE: To determine the possible health risk associated with intestinal parasite infections among children with gastroenteritis in Jeddah, Kingdom of Saudi Arabia. METHODS: This cross-sectional study was undertaken between March and August 2007 in Jeddah, Kingdom of Saudi Arabia, to detect the prevalence of intestinal parasite infections in children aged 0-10 years. Two major public hospitals took part in the study. These hospitals are King Abdulaziz University Hospital (KAUH), and King Fahad Hospital (KFH). The study involved examination of fecal samples from 500 children (24 inpatients and 476 outpatients) complaining of gastroenteritis. The samples were concentrated by formol-ethyl acetate concentration method, and microscopically examined with iodine and Ziehl Neelsen staining methods. RESULTS: The overall prevalence of intestinal parasitic infection was 33.8%. The intestinal parasites identified in both inpatients and outpatients were Blastocystis hominis 0% inpatient, 9.5% outpatient, Entamoeba histolytica/dispar (8.3% inpatient, 5.9% outpatient), Giardia lamblia (12.5% inpatient, 2.7% outpatient), Cryptosporidium spp (8.3% inpatient, 2.3% outpatient), Ascaris lumbricoides (0% inpatient, 0.4% outpatient), hookworm (4.2% inpatient, 0.8% outpatient), and Trichuris trichiura (4.2% inpatient, 1.05% outpatient). CONCLUSION: Intestinal parasitic infection is still a common health problem among children in Saudi Arabia.

A new modified technique for concentrating intestinal parasites.

The present study evaluated the diagnostic performance of a modification of the formol ethyl acetate concentration technique, with the addition of 25% acetic acid as compared with formol ethyl acetate concentration technique (FEA) and fecal parasite concentrator kit Fresh fecal material, free of ova and parasites, was pooled in a ratio of 1:4 with 10% buffered formalin to prepare a standardized specimen. Sufficient volumes of formalin-fixed suspension of Giardia lamblia cysts, Entamoeba histolytica cysts, Cryptosporidium oocysts; Ascaris lumbricoides ova, Necator americanus, Taenia spp. and Hymenolepis nana were used to seed individually 3-ml portions of the fecal specimen. The 3-ml samples were split in three parts, one processed by FEA, a second part with FPC and the third part by the modified FAEA; six smears from each sediment were examined by light microscopy. FAEA technique gave the clearest sediments and the highest numbers in most of the parasites. FAEA resulted in a higher percenttage of H. nana, Taenia spp., N. americanus, and G. lamblia per one ml of stool compared with FEA method. When compared with FPC, the same results were achieved in addition to E. histolytica.

Diagnosis of Entamoeba histolytica in symptomatic children, Jeddah City, Saudi Arabia.

Amebiasis is one of the most common parasitic infections worldwide. Entamoeba histolytica and Entamoeba dispar are two morphologically indistinguishable human protozoa parasites that are genetically distinct species. Differential diagnosis of E. histolytica (pathogenic) and E. dispar (non-pathogenic) is essential both for treatment decision and public health knowledge. Stool samples from 500 randomly selected children complaining of gastroenteritis were examined microscopically by direct wet smear and subjected to detection of E. histolytica antigen by ELISA using TechLab E. histolytica II test. E. histolytical E. dispar were also identified at molecular level by targeting the 166 bp, and 752 bp sequences of the 18Sr RNA gene of E. histolytica and E. dispar respectively using polymerase chain reaction technique (PCR). The overall prevalence of E. histolytica/dispar by microscopic examination was 30/500 (6%). E. histolytica was positive in 161500 (3.2%) by antigen detection ELISA technique, whereas 10 samples were not detected microscopically. PCR was able to confirm the presence of E. histolytica in 13/16 cases whereas the 3 samples recorded negative were positive by ELISA; even so there was a good agreement k = 0.86 between the two techniques. In conclusion, stool antigen detection test by ELISA is recommended over PCR in detecting and confirming E. histolytica amoebic enteritis.

Detection of Entamoeba histolytica/dispar in stool specimens by using enzyme-linked immunosorbent assay in the population of Jeddah City, Saudi Arabia.

This study determined the prevalence of intestinal parasites, particularly pathogenic Entamoeba sp. (E. histolytica), in patients attending three hospitals in Jeddah City, King Abdulaziz University Hospital, King Abdulaziz Hospital and King Fahad Hospital for gastro-intestinal troubles. 186 stool specimens were examined microscopically for parasites and by ELISA kit (E. histolytica II) for true E. histolytica. 83 samples (44.6%) were positive by microscopy for at least one parasite. Of which, 23 (12.4%) showed two parasites and 15 (8.1%) three parasites. Eight different parasite species were identified. The most prevalent were E. histolytica/dispar (n = 26, 31.3%) and Giardia lamblia (n = 13, 15.7%). Others were Blastocytosis hominis (n = 12, 14.5%), Entamoeba coli (n = 11, 13.3%), Trichuris trichuria (n = 8, 9.6%), Endolymax nana (n = 6, 7.2%), Hymenolepes nana (n = 4, 4.8%) and Chilomastix mesnili (n = 3, 3.6%). Only five stool samples (19%) from those identified by microscopy to contain E. histolytica/dispar, were E. histolytica positive by E. histolytica II ELISA. For the first time to the authors' knowledge the true prevalence of E. histolytica in Saudi Arabia was 2.7%. E. histolytica II ELISA proved to be a highly useful technique to differentiate pathogenic E. histolytica from non pathogenic E. dispar.