An evaluation of different saliva collection methods for detection of antibodies against hepatitis C virus (anti‐HCV)

J Oral Pathol Med (2012) 41 : 793–800 Background: Saliva samples can be used as an alternative fluid for against hepatitis C virus (anti‐HCV) detection owing to the ease of collection and excellent acceptability. This study was conducted to optimize a commercial enzyme immunoassay (EIA) to detect anti‐HCV in saliva samples. Methods: Ninety‐six individuals donated paired serum and saliva samples that were obtained, using a commercial device (Salivette) and spitting into a sterile container. Initially, elution buffer for the Salivette samples, sample volume, incubation time and temperature, and two different anti‐HCV EIAs were evaluated. Using the optimized assay, three methods for cut‐off calculation were also evaluated. Results: A 20‐fold increase in the sample volume for both collection methods was needed. Moreover, the Radim assay was the most appropriate assay for anti‐HCV detection in saliva samples, and the quality parameters were increased when a ROC curve was used to determine the cut‐off value. Using this optimized assay, the sensitivities, specificities, accuracies, positive and negative predictive values were above 90% for saliva obtained using both the Salivette and spitting methods. Using this assay, discordant false‐negative results were obtained for only two Salivette samples and five spitting samples. The concordance kappa was 93% for the Salivette method and 86.1% for the spitting method, demonstrating excellent performance. Conclusions: Saliva samples obtained for both methods can be employed for anti‐HCV detection among HCV‐infected or HCV‐suspected cases, but several modifications must be performed on commercial EIAs to obtain good results. Moreover, samples obtained with commercial devices are more appropriate for anti‐HCV detection in saliva samples.