P2382 - The Significance of Time-to-Positivity of Anti-HCV Antibody Rapid Diagnostic Test in Predicting HCV Active Viremia

Muhammad Nabeel Shafqat, MD¹, Asad Ali Choudhry, MBBS², Najam-us-Sehar Saeed, MBBS, FCPS³, Auj Chaudhry, MBBS¹, Miqdad Haider, MD⁴, Muhammad Adil, MBBS⁵, Ghania Shafqat, MBBS, FCPS⁶, Fatima Akram, MBBS, FCPS⁶, Faizan Zahoor, MBBS, FCPS^1
1District Headquarter Hospital Gujranwala, Gujranwala, Punjab, Pakistan; ²PARSA Trust-Liver Clinic, Al-Raee Hospital Gujranwala, Gujranwala, Punjab, Pakistan; ³Gujranwala Medical College, Gujranwala, Punjab, Pakistan; ⁴Heartlands Hospital, Birmingham, England, United Kingdom; ⁵District Headquarter Hospital-Gujranwala Medical College, Gujranwala, Punjab, Pakistan; ⁶Shalamar Institute of Health Sciences, Lahore, Punjab, Pakistan

Introduction: Hepatitis C virus (HCV) infection is a public health threat worldwide and a leading cause of liver related deaths. According to World Health Organization (WHO), it is estimated that 3% of the world’s population is infected with HCV. Currently, the recommended protocol is to initially screen at risk population with a point of care anti-HCV antibody rapid diagnostic test (RDT), followed by a reflex HCV RNA testing to determine active viremia. Simplification of current HCV diagnostic cascade can help achieve linkage to care in resource poor settings. The present study aimed to assess the significance of time-to-positivity (TTP) of anti-HCV RDT in predicting active viremia in sero-positive patients.

Methods: HCV screening was conducted in 18873 patients with SD Bioline HCV antibody kits to detect anti-HCV antibodies. The two step HCV diagnostic approach was adopted. During screening phase, finger needle prick sample was tested for anti-body on RDT kits. TTP was recorded at pre-determined intervals up to 20 minutes. In phase II, a second sample was obtained through venipuncture for quantitative HCV PCR analysis in all sero-positive patients. Serum HCV RNA quantification was performed with Abbott Automated Analyzer. The correlation between TTP and detectable HCV RNA levels was determined by Spearman’s correlation analysis.

Results: HCV prevalence was found to be around 6% (1132/18873). Of anti-HCV positive patients, there were 848 (75%) cases of active viremia. Amongst cases with detectable HCV RNA, patients with shorter time to positivity appeared to have higher levels of HCV RNA. Patients who had < 30 seconds TTP in the RDT kit had significantly higher viral load (893058 IU/mL), compared to patients who tested positive on RDT at 60-90 seconds and 90-120 seconds, where average HCV RNA viral load was 44619.5 IU/mL and 11530 IU/mL, respectively. Spearman’s Rank analysis showed a moderate negative correlation between TTP of anti-HCV antibody and HCV RNA values (r=-0.75, p<0.001).

Discussion: The TTP of anti-HCV antibody test is moderately correlated with HCV viremia and can be considered a valuable alternative in resource poor settings, especially in countries with high HCV prevalence. This can facilitate mass screening, reduce the economic burden of reflex HCV RNA testing and expedite timely intervention to control spread of infection and ultimately help achieve the WHO hepatitis elimination goal. Further multicenter projects on a larger scale can help substantiate the findings of our study.



Disclosures:


Muhammad Nabeel Shafqat, MD¹, Asad Ali Choudhry, MBBS², Najam-us-Sehar Saeed, MBBS, FCPS³, Auj Chaudhry, MBBS¹, Miqdad Haider, MD⁴, Muhammad Adil, MBBS⁵, Ghania Shafqat, MBBS, FCPS⁶, Fatima Akram, MBBS, FCPS⁶, Faizan Zahoor, MBBS, FCPS¹. P2382 - The Significance of Time-to-Positivity of Anti-HCV Antibody Rapid Diagnostic Test in Predicting HCV Active Viremia, ACG 2023 Annual Scientific Meeting Abstracts. Vancouver, BC, Canada: American College of Gastroenterology.