Analysis of autoimmune hepatitis with acute presentation in the early stage of illness

BACKGROUND AND AIM

There is no gold standard for making the diagnosis of autoimmune hepatitis (AIH), and the diagnosis of acute onset AIH (A-AIH) is most challenging. A-AIH sometimes develops into acute liver failure with poor prognosis if the diagnosis is delayed. Therefore, it is most important for the better prognosis to diagnose non-severe A-AIH early and treat appropriately. However, features in the early stage of A-AIH are unclear. We examined initial characteristics of non-severe A-AIH in detail and tried to find novel clinical features for the early diagnosis.

METHODS

Clinical, biochemical, immunological, radiological, and histological features of 71 patients (54 women, mean age 57.9 ± 14.3 years) with non-severe A-AIH admitted to community hospitals between 2001 and 2022 were analyzed retrospectively.

RESULT

Forty-six had no symptom on onset and liver injuries were discovered by regular medical checkups. The mean duration from onset to consultation was 25.0 ± 29.3 days. Liver histology showed acute hepatitis in 59% and chronic hepatitis in 41%. Patients with symptoms revealed more male sex (P = 0.039), higher alanine aminotransferase (P < 0.001), higher total bilirubin (P < 0.001), and higher rate of histological acute hepatitis (P = 0.0013) than those without symptoms significantly. Male sex, presence of symptoms on onset, occurrence of jaundice in the course, and histological acute hepatitis were correlated.

CONCLUSIONS

Sixty-five percent of non-severe A-AIH patients were asymptomatic on onset, suggesting that A-AIH would develop insidiously and present a longer clinical course than that reported. Male patients more often revealed true acute hepatitis clinically, biochemically, and histologically than female ones.

Analysis of non-severe acute onset autoimmune hepatitis according to the presence of radiological heterogeneity

AIM

Diagnosis of acute onset autoimmune hepatitis (A-AIH) has been difficult in that patients may not have typical clinicopathological features of AIH. In our previous reports of severe and fulminant AIH, two-thirds of them showed radiological heterogeneity: hepatic heterogeneous hypoattenuation on unenhanced computed tomography (CT) reflecting heterogeneous distribution of massive hepatic necrosis (severe centrilobular necrosis), which would be beneficial for the diagnosis. In the present study, we analyzed non-severe A-AIH patients with or without radiological heterogeneity and tried to find novel clinical features for supporting the early diagnosis.

METHODS

Clinical, biochemical, immunological, radiological and histological features of 42 patients with non-severe A-AIH at community hospitals between 2010 and 2020 were analyzed.

RESULTS

Of 42, 28 patients on whom CT scans were performed and who could be fully analyzed were enrolled. Five patients showed hepatic heterogeneous hypoattenuation on unenhanced CT. There was no significant difference in clinical, biochemical, immunological and histological features at diagnosis between the two groups according to the presence of radiological heterogeneity, although mean minimum prothrombin time activity during the course was lower in patients with heterogeneity without statistical significance (p = 0.080). All responded to treatment well and achieved initial remission within 3 months.

CONCLUSIONS

It is possible that patients with non-severe A-AIH show radiological heterogeneity reflecting centrilobular necrosis which is one of important diagnostic features of A-AIH. Accordingly, radiological heterogeneity might be beneficial for the diagnosis of A-AIH in combination with conventional clinicopathological features if it is detected in the absence of features suggestive of other liver diseases.

Diagnostic utility of radiological heterogeneity in acute severe (fulminant) autoimmune hepatitis

BACKGROUND

Histological examination is useful for the diagnosis of acute severe (fulminant) autoimmune hepatitis (AIH), but it is sometimes difficult to perform liver biopsy due to the complicated coagulopathy and ascites. We have shown that heterogeneous hypoattenuation on unenhanced computed tomography (CT) is a characteristic imaging feature of acute severe (fulminant) AIH. In the present study, we examined the utility of the imaging feature by applying the score to diagnose acute severe (fulminant) AIH.

METHODS

Twenty-three patients with acute severe (fulminant) AIH were analyzed retrospectively. Modified AIH score was created by adding three points to AIH score with/without histological points in case of the presence of heterogeneous hypoattenuation on unenhanced CT.

RESULTS

Areas of hypoattenuation were present in 15 (65%) patients, all of which were heterogeneous pattern. Five (22%) patients were diagnosed as "definite" AIH, 16 (69%) as "probable" and two (9%) as "non-diagnosis" by the revised original score without histological score. By adding three points, two of "non-diagnosis" changed to "probable" AIH, and all patients were diagnosed as AIH.

CONCLUSIONS

Modified AIH score using heterogeneous CT image finding would be beneficial especially for patients in whom histological examinations cannot be performed because of complications.

Acute presentation of autoimmune hepatitis: a multicentre study with detailed histological evaluation in a large cohort of patients

AIMS

Although liver biopsy is crucial to diagnose and guide treatment decisions, a detailed histological analysis of autoimmune hepatitis (AIH) with clinically acute presentations has not yet been performed. This study aimed to characterise the histological features and explore potential histological hallmarks to diagnose the acute presentation of AIH.

METHODS

We systematically evaluated liver specimens of 87 adult patients with acute presentation of AIH retrospectively enrolled from Japanese multicentre facilities. Each histological feature was predefined by consensus based on the diagnostic criteria.

RESULTS

Key findings were that acute presentation of AIH revealed histological features of both acute hepatitis and chronic hepatitis accompanying various degrees of fibrosis. The prominent features were lobular necrosis/inflammation (97.7%), plasma cell infiltration (96.4%), emperipolesis (89.3%), pigmented macrophages (84.5%), cobblestone appearance of hepatocytes (82.6%) and perivenular necroinflammatory activity, including centrilobular necrosis (81.4%).

CONCLUSIONS

The acute presentation of AIH represents the entire histological spectrum of acute hepatitis and chronic hepatitis with various activity grades and fibrosis stages that clinically correspond to acute-onset AIH and acute exacerbation of classic AIH, respectively. Although there are no pathognomonic features for the pathological diagnosis, the prominent presence of lobular and perivenular necroinflammatory activity, pigmented macrophages and cobblestone appearance of hepatocytes in addition to the classic AIH features, such as plasma cell infiltration and emperipolesis, are useful for the pathological diagnosis of the acute presentation of AIH.