Correction to: Strongyloides stercoralis in Patients on Corticosteroids Therapy Using Enzyme­Linked Immunosorbent Assay and Gelatin Particles Indirect Agglutination Tests: A Diagnostic Approach.

In the printed version of the article, the name of the third author was misspelled. The correct name is as follows: Amal A. El-Moamly.

Strongyloides stercoralis in Patients on Corticosteroids Therapy Using Enzyme-Linked Immunosorbent Assay and Gelatin Particles Indirect Agglutination Tests: A Diagnostic Approach.

INTRODUCTION: Patients on corticosteroids therapy (POCT) are more likely to flare up concealed Strongyloides infection and develop Strongyloides hyperinfection syndrome and/or dissemination. Such critical complications can lead to high mortality rates. Rapid detection methods are, therefore, necessary to detect Strongyloides infection in POCT with the advantage of being applicable in a developing country. METHODS: Two hundred POCT have been enrolled in this study to determine the rate of infection with Strongyloides. Three different groups of POCT (Strongyloides infected, non-infected, infected with other parasites) were used to evaluate the antibodies detection capability of two serological techniques (enzyme-linked immunosorbent assay (ELISA) and gelatin particles indirect agglutination (GPIAT) against the results of the gold standard agar plate culture (APC). RESULTS: With APC, the infection rate of Strongyloides stercoralis in POCT was 9.5% (19/200). POCT with Strongyloides infection displayed related risk factors (job, rural settlements, and soil contact) for infection combined with the subtropical nature of Ismailia Governorate. With regard to serology, ELISA detection results were poor compared to APC with sensitivity and specificity of 42.1% and 82.6%, respectively, and positive and negative predictive values of 72% and 30%. GPIAT appeared to be closely related to APC with sensitivity and specificity of 89.4% and 81.8%, respectively, and positive and negative predictive values of 80.9% and 96.7%. Statistical moderate correlation was detected between GPIAT and ELISA. CONCLUSION: The GPIAT technique is more convenient, easier, cheaper and faster to rule out the infection of Strongyloides in POCT. It might be the test of choice for routine immunodiagnosis of human strongyloidiasis.

The prevalence of parasites in commonly used leafy vegetables in South Western, Saudi Arabia.

OBJECTIVE: To determine the degree of contamination caused by parasites in commonly used leafy vegetables in Abha, Kingdom of Saudi Arabia (KSA). METHODS: We carried out the study in the Department of Clinical Microbiology and Parasitology, King Khalid University, Abha, KSA, during the period September 2004 to May 2005. Five commonly used leafy vegetables, namely, green onion, radish, watercress, lettuce and leek, were washed each in water and Tris-buffer-saline (TBS). The washing solution was then centrifuged and the sediments were examined for parasites. RESULTS: The use of TBS for the extraction, significantly increased the isolation rate (27.2%) of the parasites compared with the use of tap water (7.8%) (z=4.72 p<0.001). The prevalence of the parasites was 28% in green onion, 25% in radish, 17% in watercress, 17% in lettuce, and 13% in leek. The parasites were more common in the months of September to December. Ankylostoma duodenale, Entameba coli, Ascaris lumbricoides and Blastocystis hominis were the most common isolated parasites. We encountered 12 genera of parasites during the study and the least common was iodamoeba butschlii. CONCLUSION: The study shows that parasites are common in leafy vegetables and the use of tap water does little to remove them. The public health implications of our findings will be communicated to the Aseer regional health authorities for appropriate community health education and other necessary actions.

Selective identification of the pathogenic E. histolytica in fresh stool samples using polymerase chain reaction (PCR).

Stool samples from 93 individuals clinically presumed to have intestinal amoebiasis and subjected to microscopic examination and DNA extraction. The PCR amplification was performed using two sets of primers that differentiate between pathogenic and nonpathogenic Entamoeba DNA. Of 93 clinically positive cases, 51 (54.8%) were positive by microscopy, while 53 (56.9%) were detected by PCR as having DNA specific for either E. histolytica / E. dispar. A specificity of 85.71% and a sensitivity of 92.15% were with PCR compared to microscopy. Among 53 PCR positive specimens, three different DNA sequences were demonstrated: 8 specimens had DNA sequences specific of E. histolytica, 31 with DNA specific for E. dispar and 14 specimens have mixed DNA sequences for E. histolytica and E. dispar. PCR is a sensitive and a specific tool. PCR application is better the epidemiology in endemic areas through keeping indefinite DNA records for prospective and retrospective studies.

Incidence of Parastrongylus cantonensis larvae in different fresh water snails in Dakahlia Governorate.

Samples of snails were collected from different water bodies in Dakahlia governorate to assess a survey on the naturally infected snails and their infection rate with the Parastrongylus cantonensis larvae. The nematode P. cantonensis is associated in the etiology of eosinophilic meningeoencephalitis of man. Lanistes carinatus showed the highest rate of infection with 19-400 larvae per snail. Biomphalaria alexandrina, B. glabrata, Bulinus truncatus, Lymnaea cailliaudi (natalensis), L. alexandrina, and Cleopatra cyclostomoides were found naturally infected with the larvae of P. cantonensis for the first time in Egypt. The number of larvae per infected snail varied depending on the snail type. The highest rate (39.2%) of infected snails was collected from the end canals at Tanneekh and the lowest in the river Nile (12.5%).