Autoimmune hepatitis in practice, from diagnosis to complications: What is the role of imaging? A clinicoradiological review

Magnetic resonance imaging findings in autoimmune hepatitis: how frequent and reproducible are they?

Objective

To determine the frequency and interobserver reproducibility of the magnetic resonance imaging (MRI) features considered diagnostic for autoimmune hepatitis.

Materials and Methods

Two abdominal radiologists, blinded to pathology data, reviewed the MRI examinations of 20 patients with autoimmune hepatitis, looking for liver enhancement, lymphadenopathy, portal hypertension, and chronic liver disease. The pattern of liver fibrosis was categorized as reticular, confluent, or mixed. Interobserver agreement was assessed by calculating intraclass correlation coefficients and kappa statistics.

Results

The most common abnormal finding on MRI was surface nodularity (in 85%), followed by liver fibrosis with a reticular pattern (in 80%)-categorized as mild (in 25.0%), moderate (in 43.8%), or severe (in 31.2%)-; heterogeneous liver enhancement (in 65%); splenomegaly (in 60%); caudate lobe enlargement (in 50%); and lymphadenopathy (in 40%). The interobserver agreement was almost perfect for surface nodularity (0.83), ascites (0.89), and liver volume (0.95), whereas it was just slight and fair for the degree of fibrosis and for heterogeneous liver enhancement (0.12 and 0.25, respectively). It was also slight and fair for expanded gallbladder fossa and enlarged preportal space (0.14 and 0.36, respectively), both of which are indicative of chronic liver disease.

Conclusion

The interobserver agreement was satisfactory for surface nodularity (the most prevalent abnormal MRI finding), ascites, liver volume, and splenomegaly. Conversely, it was only slight or fair for common but less objective criteria.

A low dose of naloxone mitigates autoimmune hepatitis by regulating TLR4/NF-κB and Nrf2/HO-1 signaling pathways

Naloxone is a non-selective opiate receptor antagonist that is mainly used in the management of acute opioid overdose or intoxication. Previously, naloxone has been shown to have anti-inflammatory and antioxidant properties. Concanavalin A (Con A) model is a common and well established animal model of autoimmune hepatitis that closely resembles the pathological alterations that occur in human. The present study demonstrates that a low dose of naloxone (LD NX) has the ability to improve hepatic function and attenuate hepatic damage induced by Con A as indicated by a clear reduction in serum aminotransferase, bilirubin and enhancement of albumin production as well as liver pathological changes. Also, The proinflammatory cytokines, tumor necrosis factor-α (TNF-α), interferon- γ (IFN-γ), interleukin-6 (IL-6) and interleukin-1β (IL-1β) were highly suppressed in animals pretreated with LD NX via interference with TLR4/NF-κB as well as JNK signaling pathways. Furthermore, oxidative stress was highly attenuated in animals pretreated with LD NX as indicated by high reduction in hepatic MDA and an increase in Nrf2, HO-1 expression and subsequent production of the endogenous antioxidants, SOD, CAT and GSH. Collectively, this study demonstrates that LD NX has the ability to mitigate Con A-induced autoimmune hepatitis via modulation of inflammatory cytokines secretion and interference with reactive oxygen species generation.