Growth hormone deficiency and antipituitary antibodies in a patient with common variable immunodeficiency

Abstract

Common variable immunodeficiency (CVID) is characterized by hypogammaglobulinemia and T-lymphocytes dysfunction. Autoimmune diseases are frequent. A 10.7-yr-old female, diagnosed with CVID when 7 yr old, was referred because of short stature. She was pre-pubertal and short (height -2.86 SD score) with delayed bone age. Her intestinal absorption, routine biochemistry, heart, renal, liver, and thyroid functions were normal. Two stimulation tests for GH showed a maximum peak of 1.9 ng/ml (IGF-1: 154 ng/ml, 147-832). When the patient was 13 yr old (height -4.23 SD score, telarche and pubarche stage 2, bone age 6.25 yr), GH treatment was initiated. Despite poor compliance, the growth velocity showed improvement. Anti-thyrogobulin, anti-thyroperoxidase, anti-21-hydroxylase, and anti-tyrosine-phosphate antibodies were negative while anti- pituitary antibodies (APA) were positive. For the first time, the presence of APA (previously associated with GH deficiency in non-CVID subjects) is reported in a CVID patient. The possibility of an autoimmune involvement of the pituitary gland was previously debated for CVID patients, but had never been demonstrated. This case suggests that in CVID, the pituitary gland can be targeted by autoantibodies and thus a more comprehensive follow-up of these patients should be performed.