Criteria for autoimmune hepatitis (AIH) have been simplified over the last decade.  The 2008 AIH criteria have a high sensitivity and specificity in children (Clin Gastroenterol Hepatol 2012; 10: 417-21).

This study examined 238 patients: 41 AIH patients and 197 non-AIH patients.  Among these patients, 37 of the 41 AIH had sufficient data to calculate 2008 score using IgG or globulin & 40 of the 197 of the non-AIH had sufficient data.  Within the 37 AIH patients, 31 had IgG levels; all 37 had either IgG or globulin.  Similarly, among the 40 non-AIH patients, 26 had IgG levels available.

Among AIH patients:  the 1999 criteria categorized 29 of 31 (94%) as definite AIH and 2 of 31 (6%) as probable AIH.  The 2008 criteria: 25  definite AIH, 2 as probable AIH, and 4 were not identified as AIH; all four had fulminant hepatic failure (FHF).

The authors conclude that the simplified 2008 guidelines have high sensitivity/specificity and are easier to use.  Patients with FHF require the 1999 criteria.

• -Hepatology 2008; 48: 10, 169. Simplified diagnostic criteria: points for autoabs, IgG, histology, & absence of viral hepatitis.

Autoantibodies:

ANA or SMA 1:40                  1
ANA or SMA 1:80
or LKM
or SLA 1:40                           2*

IgG:
IgG >Upper normal limit        1
>1.10 times ULN                   2

Liver histology (evidence of hepatitis is a necessary condition)
Compatible with AIH             1
Typical AIH                            2
Absence of viral hepatitis      2

Scoring Total:

>/=6: probable AIH
>/=7: definite AIH
*Addition of points achieved for all autoantibodies (maximum, 2 points).

Additional references on AIH criteria:

• -Clinical Gastro & Hep 2011; 9: 57, 3 (editorial). Many AIH meet criteria w/o liver biopsy.
• AIH 1999 criteria:  Hepatology 2009; 50: 538. diagnosis with scoring system vs. simplified. 1999 criteria more precise. See page 539 for details:

Scoring (points in bold):
if female gender,  +2
if ALP: AST (or ALT) less than 1.5, then +2
if globulin >2 (+3), +2 if >15, +1 if >1
if ANA, >1:80 +3, 1:80 =2, 1:40 +1
if neg viral markers, +3
drug hx neg, +1
if alcohol <25g/d, +2
liver histology: if interface hepatitis +3, lymphoplasmacytic infiltrate +2
if autoimmunity in pt or 1st degree relative, then +2
if response to Rx, +2
Interpretation: if pretreatment >15 definite AIH, 10-15 probable
if posttreatment: >17 definite, 12-17 probable

Additional AIH references:

• -Gastroenterology 2011; 140: 1980. n=229. in single center, 93% achieved NL ALT w/in 12 months –though still with increased mortality compared to general population.
• -Liver Tx 2011; 17: 393. 86% 5yr pediatric (n=113) OLTx survival (same as entire cohort)
• -Hepatology 2010; 53: 926. AIH steroid failures (~20%) more likely to have worse disease at presentation. n=72
• NAPGHAN 2010 Pointers:  Rx: Typical prednisone dose is 2 mg/kg/day, max 60 mg/day (“Mieli-Vergani regimen”). 90% of patients have dramatic improvement in LFTs within 2 weeks of starting corticosteroids, 80% achieve in remission in ≤18 mos. For the 10-20% failure rate, consider non-adherence to medications or make sure that you have the right diagnosis. Most children with AIH require prolonged or indefinite treatment with steroids, albeit at low dose
• -Hepatology 2008; 48: 863. n=243. Risk factors for HCC in AIH. Main risk is cirrhosis with HCC occuring ~102 months after cirrhosis develops
• -Hepatology 2010; 52: 2247. Suggested protocol to minimize steroids: Combined Azathioprine (~1.5/kg in adults) with steroids. Use steroids for 3 months then taper to 5-10mg/day. If doing well, try to d/c steroids at 1 yr of Rx.

• -JPGN 2010; 51: 524. Use of allopurinol when Azathioprine toxicity (3 cases). Allopurinol dosed between 25mg-50mg and Azathioprine reduced to 0.5-1mg/kg/day.
• -Hepatology 2008; 48: 10, 169. Simplified dx criteria: points for autoabs, IgG, histology, & absence of viral hepatitis.

• -Hepatology 2008; 47: 9494-57. Asymptomatic PSC common in AIH –might be higher than 10%.-Clinical Gastro & Hep 2008; 6: 379. genetic factors affecting phenotype of AIH.
• -Clin Gastro & Hep 2008; 6: 1036. Use of cellcept/mycophenolate for AIH.
• -JPGN 2006; 43: 635. Use of cyclosporine initially for 6 months, then changing to AZA/steroids, n=84. Goal of CYA trough 250 +/- 50 for 1st 3 months.
• -Hepatology 2006; 43: (Suppl 1): S132. Nice review.
• -NEJM 2006; 354: 54. AIH Review.
• -Clin Gastro & Hepatology 2004; 2: 935. Reviews AIH/PSC criteria in children; use of GGT recommended.