**4.3 Gastrointestinal and hematological disorders**

Patients with PID, particularly infants and young children, may manifest chronic diarrhea, malnutrition, and malabsorption. Some individuals may undergo infections in gastrointestinal tract, such as chronic giardiasis and rotavirus [25], while others may experience a variety of autoimmune or autoinflammatory disorders including inflammatory bowel disease, atrophic gastritis with pernicious anemia, or gluten-sensitive enteropathy [20].

Hematological disorders, such as autoimmune hemolytic anemia, and/or neutropenia and/or thrombocytopenia, are also frequently seen in patients with CVID or selective IgA deficiency [26]. Patients with the Wiskott-Aldrich syndrome, a disease characterized by variable defects in B- and T-lymphocyte function, can present with reduced platelet volume and significant thrombocytopenia [27].
