Diagnostic Accuracy of Serum Hyaluronan for Detecting HCV Infection and Liver Fibrosis in Asymptomatic Blood Donors

Background: The disease caused by hepatitis C virus (HCV) is asymptomatic, silent, and progressive liver disease. In HCV-infected patients the increase in serum HA is associated with the development of hepatic fibrosis and disease progression. Methods: HCV-RNA detection was performed in all serological samples of blood donors that tested positive using HCV Ultra ELISA. Determination of hyaluronan (HA) was performed in positive HCV samples using ELISA-like fluorometric method. The HA content was compared to HCV viral load, genotype of the virus, liver fibrosis as well as ALT and GGT liver biomarkers. Results: Persistently normal ALT (<40 U/L) and GGT (<50 U/L) serum levels were detected in 75% and 69% of the HCV-Infected blood donors, respectively. Based on ROC analysis, the HA value < 34.2 ng/mL is an optimal cut-off point to exclude HCV viremia (specificity = 91%, NPV = 99%). Applying HA value ≥34.2 ng/mL significant liver fibrosis (≥F2) can be estimated in 46% of the HCV-infected blood donors. HA serum level (≥34.2 ng/mL) associated with a high ALT level (>40 U/mL) can correctly identify HCV infection and probable liver fibrosis (sensitivity = 96% and specificity = 90%) in asymptomatic blood donors. Conclusions: A high level of HA (≥34.2 ng/mL) in association with ALT (≥40 U/L) in serum can provide a good clinical opportunity to detect HCV-infected asymptomatic persons that potentially require a liver biopsy confirmation and antiviral treatment to prevent the development of advanced liver fibrosis or cirrhosis.

Signal to cut-off (S/CO) ratio and detection of HCV genotype 1 by real-time PCR one-step method: is there any direct relationship?

BACKGROUND

Polymerase chain reaction (PCR) methods play an essential role in providing data related to diagnosis, monitoring and treatment of hepatitis C virus (HCV) infection. EIA results are reported as ''reactive'' or ''non reactive'' and EIA S/CO ratio may also be reported as ''high'' or ''low.'' This study aimed to evaluate the performance of a real-time RT-PCR and assess whether there is relationship between S/CO and PCR results.

STUDY DESIGN AND METHODS

Sera from blood donors were analyzed by Enzyme-Linked Immunosorbent Assay (ELISA) and RT-PCR assay to detect HCV infection.

RESULTS

The RT-PCR assay to genotypes 1a/b showed an acceptable linear response in serial dilutions. The samples were divided into two groups based on their serological results: group A--S/CO ratio < 3 (60 samples) and group B--S/CO ratio > 3 (41 samples). Viral loads were confirmed positive in group B samples in 90%, and in group A samples were confirmed positive in only 13% by RT-PCR.

CONCLUSION

The methodology used was able to detect the presence of RNA-HCV genotype I in 90% of the samples serologically positive in group B. All negative samples were sent to search for other genotypes of HCV (genotypes 2-6) and were confirmed as negative. These data suggests that these negative samples may have HCV RNA viral load below the detection limit of our test (310 IU/ mL), or a false positive result in serological test, or spontaneous viral clearance occurred.

High prevalence of celiac disease in Brazilian blood donor volunteers based on screening by IgA antitissue transglutaminase antibody

OBJECTIVE

To study the prevalence of celiac disease among blood donor volunteers based on screening by IgA antitissue transglutaminase antibody, followed by a confirmatory small intestine biopsy.

METHODS

The transversal study involved 3000 potential blood donors, residing in the city of Sao Paulo, Brazil. The participants were gender divided into 1500 men and 1500 women, with an average age 34.4+/-10.8 years, and included blood donor volunteers who could be turned down owing to anemia. All participants answered a questionnaire concerning the presence of diarrhea, constipation or abdominal pain during the 3 months before the study. Each participant with human recombinant IgA antitissue transglutaminase antibody level above 10 U/ml was invited to undergo a small intestine biopsy by means of an upper gastrointestinal endoscopy. The presence of villous atrophy and a positive antibody test were suggestive of possible celiac disease.

RESULTS

Antitissue transglutaminase antibody was positive in 1.5% (45/3000) of the study population. Among the antibody-positive group, 21 (46.6%) agreed to have a biopsy performed, and within them the histological pattern of villous atrophy was confirmed in 66.7% (14/21). Consequently, the suggestive prevalence of celiac disease was at the minimum, one per 214 of the potential blood donor volunteers. A significant association was found between celiac disease and the symptoms of diarrhea, constipation and abdominal pain.

CONCLUSIONS

The prevalence of celiac disease in Sao Paulo city is high and comparable to that observed in European countries. It is possible that in Brazil the prevalence of this disease had previously been underestimated.