[Comparative studies on the diagnosis of clonorchiasis by IEST and IFAT]

Area of Science:

• Medical Parasitology
• Immunodiagnostics
• Infectious Diseases

Background:

• Clonorchiasis is a significant public health concern in endemic areas.
• Accurate serological diagnostic methods are crucial for disease control and management.
• Previous diagnostic approaches had limitations in sensitivity and specificity.

Purpose of the Study:

• To evaluate the efficacy of immunoenzymatic staining technique (IEST) and indirect fluorescent antibody test (IFAT) for serological diagnosis of clonorchiasis.
• To compare the diagnostic performance, including positive and false positive rates, of IEST and IFAT.
• To assess the cross-reactivity of these methods with other parasitic infections.

Main Methods:

• Frozen sections of adult Clonorchis sinensis were used as antigen.
• IEST and IFAT were employed to detect antibodies in sera from 51 clonorchiasis cases and 50 healthy individuals.
• Sera from patients with schistosomiasis and paragonimiasis were tested to evaluate cross-reactivity.

Main Results:

• IEST achieved a positive rate of 92%, while IFAT yielded 88%, with no statistically significant difference (P > 0.05).
• False positive rates were 2% for IEST and 4% for IFAT.
• Cross-reactions were observed: 14% with IEST and 14% with IFAT for acute schistosomiasis; 5% with IEST and 10% with IFAT for chronic schistosomiasis; 0% for both with paragonimiasis.

Conclusions:

• Both IEST and IFAT are valuable tools for the serological diagnosis of clonorchiasis.
• The gut-associated antigen of Clonorchis sinensis is effectively demonstrated by these techniques.
• IEST may be more suitable for large-scale field surveys due to its performance characteristics.