Azadeh Zare Feizabadi - Student Research Committee, Mashhad University of Medical Sciences, Mashhad, Iran
Abdolreza Malek - Department of Pediatrics, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
Hamid Ahanchian - Allergy Research Center, Mashhad University of Medical Sciences, Mashhad, Iran

The B lymphocyte developmental blocks agammaglobulinemia, leading to peripheral B cell depletion and plasma immunoglobulin reduction. Agammaglobulinemia is a rare yet severe disease since it is presented with recurrent sinopulmonary and skin, central nervous system, bone, and joint infections. The onset of the disease is reported to be at the age of six months. Associations have been reported between arthritis and immunodeficiency disorders, such as agammaglobulinemia and common variable immunodeficiency (CVID). This study aimed to present the case of a 3.5-year-old female with a three-month history of the swelling of the left knee, mimicking oligoarticular juvenile idiopathic arthritis. After the initiation of immunosuppressive treatment, the patient developed large, tender, erythematous lesions on the inguinal region bilaterally, which developed to ecthyma gangrenosum due to Pseudomonas. The patient’s mother also reported recurrent episodes of infections since the patient was a one-year-old infant. Subsequent to the immunological examinations and laboratory tests, the patient was diagnosed with autosomal recessive agammaglobulinemia due to low serum immunoglobulin concentration and the absence of peripheral B cells. Primary immunodeficiency conditions (particularly agammaglobulinemia) and CVID should be considered in children with arthritis and recurrent infections. Moreover, immunological analysis should be performed prior to treatment in these children

Agammaglobulinemia, Immunoglobulins, Juvenile idiopathic arthritis