Igg4-associated cholangitis K83.0

Autoimmunologically induced, chronic inflammation of the bile ducts, which belongs to the group of IgG4-associated infections.

Pathogenetically, immunoglobulin IgG4 plays an important role in all IgG4-associated (autoimmune) diseases (Trampert DC et al. (2018). In several independent IAC cohorts a disproportionately high proportion of workers with high exposure to solvents, industrial dusts/oils and pesticides could be detected (Herta T et al. 2018)

Patients with IgG4-associated cholangiopathy are usually > 60 years; m>w =8:1 (Herta T et al. 2018)

In the early stages asymptomatic. Later icterus, itching, unclear upper abdominal pain, weight loss. 85.0% of patients with autoimmune pancreatitis have associated autoimmunological cholangitis (AIC). (Buechter M et al. 2017).

Imaging shows a symmetrical, circular wall thickening which may also affect non-stenosed bile duct areas. Criteria for IAC are a pathological cholangiogram (type 1-4):

• type 1: isolated distal ductus hepaticus communis (DHC) stenosis
• Type 2: diffuse stenoses
• Type 3: Hilary and distal DHC stenosis
• Type 4: Isolates hilary DHC stenosis.

IgG4 in serum increased (diagnostically relevant if the value is 4x higher than the normal value); IgG4-positive cells in bile duct cytology.

Coexistence with AIP, sialadenitis(Mikulicz syndrome) or retroperitoneal fibrosis; characteristic histological findings with infiltration of IgG4-positive plasma cells In case of uncertain attribution the diagnosis can be made ex juvantibus: evaluation of the healing success by therapy with glucocorticosteroids (good response to therapy with glucocorticosteroids).

In terms of differential diagnosis, all primary and secondary forms of sclerosing cholangitis (K83.0) (PSC: in 60% of cases detection of ANA and pANCA) as well as pancreatobiliary tumours (Roos E et al. 2018) must be considered. In about 50-80% of cases there is an association with autoimmune pancreatitis type 1 (K86.1).

Excellent response to systemic glucocorticosteroid therapy. Long-term therapy necessary. High recurrence rate. Possible combination with azathioprine.

1. Buechter M et al (2017) Outcome and Genetic Factors in IgG4-Associated Autoimmune Pancreatitis and Cholangitis: A Single Center Experience. Gastroenterol Res Pract 2017:6126707.
2. Herta T et al (2018) IgG4-associated cholangitis - clinical presentation of an overlooked disease entity. Internist (Berl) 59:560-566.
3. Roos E et al (2018) IgG4-associated cholangitis in Patients Resected for Presumed Perihilar Cholangiocarcinoma: a 30-Year Tertiary Care Experience. On J Gastroenterol 113:765-772.
4. Trampert DC et al (2018) On the role of IgG4 in inflammatory conditions: lessons for IgG4-related disease. Biochim Biophys Acta 1864:1401-1409.