New Thoughts on Immunoglobulin G4-Related Sclerosing Cholangitis

A case of hilar biliary cystadenoma with elevated IgG4 levels

Cholangiocytic adenoma in the hilar bile duct is rare, and elevated IgG4 at the same time is extremely rare. This situation has not been reported in the literature. Nonetheless, the current case involved hilar biliary cystadenoma with elevated IgG4 levels. A 66-year-old man presented at this hospital with dark tea-colored urine. Preoperative imaging studies suggested hilar cholangiocarcinoma. This case demonstrates the difficulty of preoperative diagnosis of benign hilar lesions and the rarity of two combined benign lesions. A point of contention is whether this case should be treated with surgery or hormone therapy.

Serum IgG4 cut-off of 70 mg/dL is associated with a shorter time to cirrhosis decompensation and liver transplantation in primary sclerosing cholangitis patients

BACKGROUND

Primary sclerosing cholangitis (PSC) is an immune-mediated biliary disorder of unknown etiology with no effective treatment. The purpose of this study was to better prognosticate the development of cirrhosis, decompensation, and requirement for liver transplantation (LT) in PSC patients based on serum immunoglobulin G4 (IgG4) levels.

METHODS

A retrospective chart review was conducted on PSC patients seen at the University of Alberta Hospital between 2002 and 2017. PSC patients were categorized as high IgG4 group (≥70 mg/dL) or normal IgG4 group (<70 mg/dL). Laboratory parameters, clinical characteristics, and outcomes were compared between the groups.

RESULTS

One hundred and ten patients were followed over a mean period of 7.3 (SD 5) years. Seventy-two patients (66%) were male, the mean age at diagnosis of PSC was 35 (SD 15) years, and inflammatory bowel disease (IBD) was present in 80 patients (73%). High IgG4 levels were found in 37 patients (34%). PSC patients with high IgG4 had a shorter mean cholangitis-free survival time (5.3 versus 10.4 years, p = 0.02), cirrhosis-free survival time (8.7 versus 13.0 years, p = 0.02), and LT-free survival time (9.3 years versus 18.9 years, p <0.001). IgG4 ≥70 mg/dL was independently associated with liver decompensation and LT-free outcomes. A cut-off IgG4 value of ≥70 mg/dL performed better than a cut-off value of ≥140 mg/dL to predict time to LT (area under the curve [AUC] 0.68, p = 0.03, sensitivity 72%, specificity 78%).

CONCLUSIONS

Serum IgG4 ≥70 mg/dL in PSC predicts a shorter time to cirrhosis decompensation and LT.

IgG4-related disease: Changing epidemiology and new thoughts on a multisystem disease

IgG4-related disease (IgG4-RD) represents an immune-mediated fibroinflammatory condition with peculiar histopathologic changes that can affect various organs. In 2012 its unified nomenclature was published, which allows to abandon other synonymous names. Up to now, only little is known about its epidemiology around the world. However, although it is generally considered a rare condition, the number of patients with IgG4-RD is increasing enormously. Likewise, the annual number of publications on this subject has increased progressively. The spectrum of clinical manifestations in IgG4-RD is highly variable, depending on the severity of the disease as well as the presence of organ(s) involvement. This review gives an overview on changing epidemiology of IgG4-RD focusing the attention on the large cohorts of patients published in the literature.

Isolated IgG4-related sclerosing cholangitis with normal serum IgG4 levels-A case report

The isolated IgG4-SC that absent from AIP is quite rare and difficult to diagnose. We presented a case of isolated IgG4-SC with the normal serum IgG4 which was hard to differentiate with cholangiocarcinoma. Under such circumstances, liver pathology has a pivotal role in the diagnosis.

Colestasis en el adulto: enfoque diagnóstico y terapéutico. Revisión de tema

La colestasis es uno de los motivos de consulta más frecuentes en hepatología. Se genera por una alteración en la síntesis, la secreción o el flujo de la bilis, a través del tracto biliar. Esta se define por una elevación de enzimas como la fosfatasa alcalina (Alkaline Phosphatase, ALP) y la gamma-glutamil transferasa, y en estadios tardíos con la hiperbilirrubinemia, al igual que con otras manifestaciones clínicas, tales como el prurito y la ictericia. El enfoque diagnóstico implica establecer el origen de dicha elevación, determinando si es intrahepática o extrahepática. Si es intrahepática, se debe esclarecer si proviene de los hepatocitos o de la vía biliar de pequeño y de gran calibre. El tratamiento dependerá de la etiología, por lo cual es importante un diagnóstico preciso. En esta revisión se presenta la fisiopatología y un enfoque diagnóstico y terapéutico.

The significance of serum IgG4 and CA19-9, autoantibodies in diagnosis and differential diagnosis of IgG4-related sclerosing cholangitis

OBJECTIVE

To investigate the value of serum levels of IgG₄ and CA19-9, and autoantibodies in the diagnosis of IgG₄-related sclerosing cholangitis (IgG₄-SC).

METHODS

We detected the serum IgG₄ and CA19-9 of 45 IgG₄-SC patients, 173 non-IgG₄-SC patients and 48 healthy controls by immunoassay and chemiluminescence, respectively, with antinuclear antibody (ANA), anti-neutrophil antibody (ANCA), anti-smooth muscle antibody (SMA) and anti-mitochondrial antibody (AMA) level detected by indirect immunofluorescence. Then analyze the detection results.

RESULTS

(1) The positive rates of ANA, ANCA, SMA and AMA in patients with IgG₄-SC were 40%, 6.67%, 0 and 2.22%. Among them, the positive rate of ANA was significantly higher than that of the healthy control group (p < .01), and the positive rate of ANA, ANCA, SMA and AMA were significantly different from that of the non-IgG₄-SC group (p < .05). (2) Serum levels of IgG₄ and CA19-9 increased significantly in patients with IgG₄-SC compared with the healthy controls (p < .01). The areas under the ROC curve (AUC) of IgG₄ and CA19-9 were 0.9750 and 0.6498, respectively (p < .05).

CONCLUSION

The high levels of serum IgG₄ and CA19-9, and autoantibodies detections are of great important clinical value in diagnosis and differential diagnosis of IgG₄-SC.

[IgG4-associated diseases : Essentials for pathologists and radiologists]

Immunoglobulin G4-associated (IgG4) autoimmune diseases are systemic multiorgan diseases with variable clinical presentation. Principally, all organs can be affected. All IgG4-associated diseases have the same morphological correlate in common, which includes lymphoplasmacellular inflammation with abundant IgG4-positive plasma cells, obliterative phlebitis and storiform fibrosis, each with a variable manifestation. The exact pathogenesis is not yet completely understood; however, as in most cases glucocorticoids induce a prompt clinical response to therapy, this new multisystemic disease must be taken into consideration not only by pathologists but also by radiologists.

IgG4-related sclerosing cholangitis overlapping with autoimmune hepatitis: Report of a case

BACKGROUND

IgG4-related sclerosing cholangitis (IgG4-SC) is the biliary manifestation of IgG4-related disease (IgG4-RD) but the presence of IgG4-SC in the porta hepatis is difficult to differentiate from hilar cholangiocarcinoma (HCCA). IgG4-related autoimmune hepatitis (IgG4-related AIH) is extremely rare and it is not fully clear whether IgG4-related AIH is a hepatic manifestation of IgG4-RD or a subtype of AIH.

CASE PRESENTATION

We present a rare case of a 52-year-old male who was admitted with obstructive jaundice and itchy skin. He primarily presented a severe bile duct stricture in the porta hepatis and an elevated serum level of carbohydrate antigen 19-9 (CA19-9) mimicking HCCA. The patient underwent a surgical resection of the left hepatic lobular and cholecyst as well as common bile duct with a right hepatico-jejunostomy. He was finally diagnosed as IgG4-SC accompanied with IgG4-related AIH by immunohistochemistry, but he lacked conventional autoantibodies. The patient responded well to steroid therapy and remains healthy with no signs of recurrence at six-month follow-up.

CONCLUSION

This is the first case report that hepatic portal IgG4-SC overlapping with IgG4-related AIH without the presence of conventional autoantibodies. Additionally, we suggest that IgG4-RD should be always considered in case of a bile duct stricture in the porta hepatis to avoid unnecessary surgical operation.

Adult bile duct strictures: differentiating benign biliary stenosis from cholangiocarcinoma

Biliary epithelial cells preferentially respond to various insults under chronic pathological conditions leading to reactively atypical changes, hyperplasia, or the development of biliary neoplasms (such as biliary intraepithelial neoplasia, intraductal papillary neoplasm of the bile duct, and cholangiocarcinoma). Moreover, benign biliary strictures can be caused by a variety of disorders (such as IgG4-related sclerosing cholangitis, eosinophilic cholangitis, and follicular cholangitis) and often mimic malignancies, despite their benign nature. In addition, primary sclerosing cholangitis is a well-characterized precursor lesion of cholangiocarcinoma and many other chronic inflammatory disorders increase the risk of malignancies. Because of these factors and the changes in biliary epithelial cells, biliary strictures frequently pose a diagnostic challenge. Although the ability to differentiate neoplastic from non-neoplastic biliary strictures has markedly progressed with the advance in radiological modalities, brush cytology and bile duct biopsy examination remains effective. However, no single modality is adequate to diagnose benign biliary strictures because of the low sensitivity. Therefore, understanding the underlying causes by compiling the entire clinical, laboratory, and imaging data; considering the under-recognized causes; and collaborating between experts in various fields including cytopathologists with multiple approaches is necessary to achieve an accurate diagnosis.