Year : 2016 | Volume
: 9 | Issue : 2 | Page : 87--94
Evaluation of polymerase chain reaction (PCR) as a diagnostic technique for acanthamoebic keratitis
Laila A Aboul-Magd1, Beessa E Abaza1, Waleed M Nada2, Faten A Mohammed1, Afaf A Taha1, Sabah M.A Mohamed1, Elshaimaa M Ebrahim1
1 Department of Medical Parasitology, Faculty of Medicine, Zagazig University, Zagazig, Egypt
2 Department of Ophthalmology, Faculty of Medicine, Zagazig University, Zagazig, Egypt
Background Techniques used to diagnose Acanthamoeba keratitis (AK), a sight-threatening corneal infection, are either insensitive or time-consuming. Early and accurate diagnosis and appropriate therapy are the key to a good prognosis.
Objective The objective of this study is to shed light on the efficacy of PCR in the diagnosis of AK in comparison with other diagnostic techniques.
Patients and methods Corneal swabs and scrapings from 95 cases suspected to have AK were examined by microscopy, culture on non-nutrient agar seeded with the avian fecal Escherichia coli AFEC49, and by PCR targeting the 18S rRNA gene.
Results The highest number of positive swabs and scrapings was detected by the PCR technique (5.26 and 27.37%, respectively), followed by culture (1.05 and 13.68%, respectively), and the lowest was detected by direct microscopy (0 and 7.37%, respectively). Corneal scrapings showed more positive cases than corneal swabs with statistically significant differences irrespective of the technique used. PCR results were significant versus culture (P<0.05) and direct microscopy (P<0.001). Out of the 26 positive cases, 20 were contact lens wearers, 13 were swimming pools users, five had a history of eye trauma, and five had undergone previous eye operation.
Conclusion PCR proved to be a better technique for the detection of Acanthamoeba infection compared with direct microscopy and culture techniques. Scrape specimens are more efficient than swabs in detecting Acanthamoeba by different diagnostic techniques. The important risk factors of AK were contact lens wearers, use of swimming pools, a history of previous eye operation as well as eye trauma.
Faten A Mohammed
Department of Medical Parasitology, Faculty of Medicine, Zagazig University, Zagazig, 44519
|How to cite this article:|
Aboul-Magd LA, Abaza BE, Nada WM, Mohammed FA, Taha AA, Mohamed SM, Ebrahim EM. Evaluation of polymerase chain reaction (PCR) as a diagnostic technique for acanthamoebic keratitis.Parasitol United J 2016;9:87-94
|How to cite this URL:|
Aboul-Magd LA, Abaza BE, Nada WM, Mohammed FA, Taha AA, Mohamed SM, Ebrahim EM. Evaluation of polymerase chain reaction (PCR) as a diagnostic technique for acanthamoebic keratitis. Parasitol United J [serial online] 2016 [cited 2018 Jun 19 ];9:87-94
Available from: http://www.new.puj.eg.net/article.asp?issn=1687-7942;year=2016;volume=9;issue=2;spage=87;epage=94;aulast=Aboul-Magd;type=0