Review Article

A New Twist to a Chronic HCV Infection: Occult Hepatitis C

Table 1

Characteristics of occult hepatitis C infection (OCI)+.

Secondary OCICryptogenic OCI

Evidence of liver injury
 ALT elevatedNoYes
 Histological lesions
  Inflammatory: minimal to mod. OccasionalFrequent
  Fibrotic: minimal to severeFrequentFrequent
Organs involved
 LiverYesYes
 Lymphatic system (PBMC)YesYes
Anti-HCV detectionPositiveNegative
HCV-RNA detection
 SerumYesYes
 PBMCYesYes
 LiverYesYes
Longevity of persistenceAt least 9 yearsUnknown

Secondary OCI: residual infection continuing after spontaneous resolution or after achieving apparent SVR following HCV therapy.
Antibodies against HCV can be detected in up to 40% in cryptogenic OCI.
+Adopted from Pham et al. [19], Liver International, 2010; 502-11.