Giardiasis mimicking celiac disease in a patient of common variable immunodeficiency.

An adolescent boy presented to pediatrics outpatient department with complaints of recurrent diarrhea, nausea, vomiting, and pedal edema since 3-4 months, with no relief even after taking treatment. His investigation revealed decreased serum IgA, IgG, and IgM levels with hypoproteinemia. Duodenal biopsy showed features of celiac disease (CD), but tissue transglutaminase IgA was negative. In stool examination, plenty of Giardia lamblia cysts and eggs of Hymenolepis nana were present. He improved on treatment and remained asymptomatic for 4 months. However, he again developed symptoms and succumbed to his illness. In patients of common variable immunodeficiency (CVID), who present with features of CD, coinfection, especially with G. lamblia and other parasites must always be kept in mind. The aim is to report a case of recurrent giardiasis with CVID mimicking CD from Western Rajasthan, India.