DIAGNOSIS OF HUMAN CYSTIC ECHINOCOCCOSIS BY DETECTING ANTIGEN B IN SERUM AND URINE USING NANOMAGNETIC BEADS-ENZYME LINKED IMMUNOSORBENT ASSAY

Document Type : Original Article

Authors

1 Department of Parasitology, Faculty of Medicine, Ain-Shams University, Cairo 11566

2 Department of Parasitology, Theodore Bilharz Research Institute, Imbaba 30, Giza, Egypt

Abstract

Cystic echinococcosis (CE) is usually asymptomatic, and commonly presents by pressure
symptoms according to its location. Diagnosis of CE is currently based on imaging techniques,
which may not be available in some areas and antibody detection in serum, with its known several
drawbacks. Conversely, antigen detection has proven its efficacy in serodiagnosis of CE.
The study evaluated the efficacy of Nanomagnetic beads (NMB)-sandwich ELISA for diagnosis
of CE by detection of Echinococcus (E.) granulosus Antigen B (AgB) in serum and urine samples
as compared with sandwich ELISA. A total of 42 individuals were classified into 3 groups;
CE infection group, other parasitic infections group and control group. E. granulosus AgB was
prepared from human hydatid cysts to produce anti-E. granulosus AgB-immunoglobulin (Ig) Gpoly-
clonal Abs in rabbit, after purification, to detect AgB level in serum and urine samples by
sandwich ELISA and NMB-sandwich ELISA. Using sandwich ELISA, AgB was detected in sera
of CE patients with sensitivity and specificity of 88.9% & 91.7%, respectively. In urine samples,
sandwich ELISA detected AgB in CE patients and the sensitivity and specificity were
83.3% and 87.5%, respectively. NMB-sandwich ELISA detected AgB in serum samples of CE
patients with a sensitivity and specificity of 94.4% and 95.8%, respectively, whereas in urine
samples it was detected in CE cases and the sensitivity and specificity were 88.9% and 95.8%,
respectively, without significant statistical difference (p>0.05) between serum and urine samples
for detection of AgB when examined by either sandwich ELISA or NMB-sandwich ELISA.
The best accuracy was obtained with NMB-sandwich ELISA detecting AgB in serum samples
(95.2%), with a slightly lower accuracy of 92.9% when using urine samples. NMBsandwich
ELISA is efficient for detection of E. granulosus AgB in serum samples. Moreover,
urine samples might be a good alternative to serum samples for the detection of AgB.

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