**4. Conclusion**

*Cells of the Immune System*

**3.7 Treatment**

steroid therapy [11].

requirements to accurately diagnose EC [6]:

treating EC if there is diagnostic uncertainty.

a retrograde diagnosis (see **Figure 5**) [10].

2.Eosinophilic infiltration on histopathology;

absence of treatment or subsequent steroid therapy.

contrast-enhanced ultrasound (CEUS). However, they suggested the following

3.Regression of the stricture or resolution of other biliary abnormalities in the

Even though EC is a self-limiting disease, it has a variable course, making precise

According to the literature, two cases of EC described a stricture in the common hepatic duct that regressed spontaneously without any medical intervention within 3 weeks, but most of the published cases of EC were treated surgically and received

treatment recommendations difficult. The challenge remains to exclude malignancy, which is not always possible with various imaging modalities and biopsies. Hence, mandatory surgical intervention is an effective and definitive measure of

Seow-En et al. suggested that the best option to simultaneously treat a stricture, exclude malignancy, and attain a definite diagnosis of EC is surgical intervention. They also described the advantages of surgery over medical therapy, indicating that medical treatment does not eradicate the chance of recurrence and that it could put patients at risk of complications of repeated

*(a) Severe degree of periductal onion skin fibrosis (hematoxylin and eosin stain displaying 2× magnification). (b and c) The inflammatory infiltrates around the partially damaged bile duct are mostly eosinophilic cells (hematoxylin and eosin stain displaying 10× magnification). (d) The eosinophilic count exceeds 40 cells per* 

*HPF (hematoxylin and eosin stain displaying 40× magnification).*

1.Thickening of the biliary wall or narrowing of the biliary tree;

**178**

**Figure 5.**

In conclusion, EC is an uncommon, benign, and self-limiting cause of biliary stricture. Although this disease has a good response to corticosteroid therapy, it often mimics cholangiocarcinoma which makes reaching a definite diagnosis by clinical and radiological findings difficult. Hence most cases are treated surgically and receive a retrograde diagnosis.
