AIH guidelines Flashcards
Definition of AIH
Characteristic histologic abnormalities (lymphoplasmacytic interface hepatitis),
-elevated AST, ALT
-elevated total IgG and the presence of one or more characteristic autoantibodies
- exclusion of viral, hereditary, cholestatic liver injury and DILI
Acute severe AIH definition
Jaundice, INR > 1.5 < 2, no encephalopathy; no previously recognized liver disease
ALF definition
INR ≥ 2; hepatic encephalopathy within 26 weeks of onset of illness; no previously recognized liver disease
AIH biochemical vs histological remission
biochem: Normalization of serum AST, ALT, and IgG* levels
histo: Absence of inflammation in liver tissue after treatment
AIH treatment failure vs incomplete response vs relapse
treatment failure: Worsening laboratory or histological findings despite compliance with standard therapy
incomplete response: Improvement of laboratory and histological findings that are insufficient to satisfy criteria for remission
AIH relapse
Exacerbation of disease activity after induction of remission and drug withdrawal (or nonadherence)
AIH treatment intolerance
Inability to continue maintenance therapy due to drug-related side effects
AIH epidemiology
- female predominant
- bimodal (age 10-30 & 40-60)
What is interface hepatitis?
Inflammation of periportal hepatocytes (as compared to lobular hepatitis)
Type 1 AIH vs Type 2 AIH
type 1:
+ ANA or ASMA/(anti-actin is subset of ASMA)
type 2:
+ anti-LKM 1
negative ANA/ASMA
20% of AIH are negative for all these auto-antibodies (sero-negative AIH). Can have +anti-SLA (very specific)
Atypical antibodies
anti-SLA - associated w/ severe disease and relapse. High specificity
p-ANCA - NOT specific. Also seen w/ PSC, AIH-PSC overlap, UC, minocycline DILI
AIH diagnostic algorithm
ANA, SMA + liver biopsy
Labs:
If negative, check SLA, pANCA, ttG, AMA
SLA + = AIH
pANCA+ = AIH or PSC
+ttG = celiac disease
+ AMA = PBC, overlap, AIH+AMA
all negative = antibody-negative PBC
Liver biopsy:
If interface hepatitis +- plasma cells = AIH
Bile duct injury or loss = overlap, PBC, or PSC
Fat = MASH or AIH/MASH
AIH histologic findings
interface hepatitis +/- lobular hepatitis, centrilobular necrosis
emperipolesis (penetration of one intact cell into another intact cell)
hepatocyte rosettes
Histologic features of AIH w/ ALF
- Central perivenulitis
- Plasma cell enriched inflammatory infiltrate
- Massive hepatic necrosis
- Lymphoid follicles
Most common presenting symptom of AIH?
Fatigue
Pruritus is NOT seen. Physical signs usually absent.
~1/4 - 1/3 of patients are asymptomatic
Imaging finding of acute severe hepatitis?
65% of patients have heterogenous hypoattenuated liver on CT non-con
Concurrent immune diseases
- more common in women
- over 60: thryoid/RA
- <30: IBD, AIHA
**all should be screened for thyroid and celiac. Consider workup for IBD, AIHA, DM, others.
What are the Paris criteria?
- identify patients w/ AIH-PBC overlap
Need to meet at least 2 of the following PBC criteria:
1) ALP >= 2x ULN or GGT >=5x ULN
2) presence of +AMA
3) florid bile duct lesions on histo
Criteria for AIH in the setting of PBC:
- interface hepatitis
- ALT >= 5x ULN
- IgG > 2x ULN or ASMA
Criteria for AIH-PSC overlap
- typical AIH features
- lack of AMA
- evidence of large duct PSC (ERCP/MRCP) or small duct PSC (histo w/ onion skinning)
All patients with AIH and UC need to be evaluated for what?
large duct PSC
Drugs associated with AIH-like injury?
- minocycline
-nitrofurantoin - infliximab
Other common ones: alpha-methyldopa, adallimumab, halothane,
Characteristics of ALH DILI?
- latency varies
- mainly women
- may have fever, rash, eosinophilia
- concurrent AI diseases unusual
- no HLA association
- rarely causes cirrhosis
- rarely relapses
biopsy features similar to AIH except cirrhosis is rare
Treatment of ALH?
- remove offending agent
-consider steroids if:
– meet’s Hy’s law (aminotransferase >3x ULN and TB >2x ULN)
– fails to improve w/ drug withdrawl
– worsening of symptoms/labs
