Introduction: Impaired immunoglobulin production is linked to Common Variable Immunodeficiency (CVID), which can be manifested as autoimmune or celiac-like enteropathy. Distinguishing between CVID-related enteropathy and true celiac disease can be difficult especially when there are no serological markers.

Case Description: A 52-year-old man who had been previously treated for lung adenocarcinoma and had a history of CVID on immunoglobulin replacement therapy was assessed for persistent diarrhea. Lower limb edema and hypoalbuminemia were found during the initial work-up and paraneoplastic etiology was ruled out by imaging. The patient underwent upper and lower GI endoscopy which showed scalloping of the duodenal folds and histology consistent with celiac disease.

After initial response to strict gluten-free diet the patient developed relapse with severe weight loss and protein loosing gastroenteropathy. Under the suspicion of CVID-related enteropathy rather than refractory celiac disease he was successfully treated with oral budesonide.

Conclusion: Although celiac-like enteropathy in CVID may resemble classical celiac disease, it frequently exhibits no IgA serological response and may only partially respond to gluten-free diet. It is important to distinguish between CVID-associated enteropathy and true celiac disease especially in patients who continue to experience symptoms despite strict gluten withdrawal since they can successfully respond to immunomodulatory treatment like budesonide.