[Common variable immunodeficiency: digestive involvement of a systemic disease].

Common variable immunodeficiency is characterized by a primary deficiency in antibody production that is clinically manifested by respiratory recurrent infections and gastrointestinal diseases (infectious, inflammatory and neoplastic). Above 50% of the patients have diarrhea and 10% develop idiopathic malabsorption and weight loss. We present the case of a 34-year-old woman submitted to our service for chronic diarrhea, abdominal pain and bloating and history of recurrent respiratory infections since childhood. The laboratory assessment showed severe hypoproteinemia and confirmed low IgG, IgA and IgM levels. Upper gastrointestinal endoscopy and videocapsule endoscopy showed a nodular duodenum with multiple polypoid-like formations all through the small bowel. Histology confirmed chronic duodenitis and Giardia lamblia infection. With the diagnosis of common variable immunodeficiency, monthly intravenous gammaglobulin infusion was initiated and metronidazole was indicated for Giardia lamblia infection achieving excellent clinical and laboratory response.