THU243 Fitting Together The Pieces Of The Puzzle Between Isolated ACTH Deficiency And Immunodeficiency: DAVID Syndrome

Disclosure: K.V. Buchanan: None. A.C. Hurst: None. A.P. Ashraf: None. Objectives: DAVID syndrome is a rare genetic disorder with common variable immunodeficiency (CVID) and anterior pituitary hormonal deficiencies due to a pathogenic variant in NFKB2. We aim to describe asymptomatic ACTH deficiency identified after the diagnosis of CVID in a patient with DAVID syndrome. Methods: A retrospective chart review of a patient with DAVID syndrome was performed. Results: The patient is a 15 year and 9-month-old female with weight in the 71(st) percentile and height in the 64(th) percentile, who was diagnosed with DAVID syndrome at 10 years through a Primary Immunodeficiency panel which identified a pathogenic variant in NFKB2 c.2557C>T,p.Arg853* and a variant of unknown significance in STAT2 c.1301C>T (p.Thr434Met). The panel was performed due to the patient’s history of recurrent sinus infections, hypogammaglobulinemia, and alopecia totalis. The patient did not have symptoms of ACTH deficiency including hypoglycemia and hypotension. After the genetic diagnosis was made, an anterior pituitary hormone evaluation was performed which showed an ACTH <5 pg/ml, AM cortisol <0.2 mcg/dL, TSH 3.48 uIU/ml, FT4 0.82 ng/dL, thyroid peroxidase antibody 29 IU/mL (normal <9), somatomedin-c 44 ng/mL (reference range 152-593), LH 5.36 mIU/mL, and FSH 14.25 mIU/mL. Adrenal insufficiency was diagnosed since the patient did not show incremental cortisol response (serum cortisol <0.2 mcg/dL at 30 and 60 minutes) post Cosyntropin stimulation test. The patient had normal electrolytes. Hydrocortisone replacement therapy was initiated. A growth hormone stimulation test was not performed since the patient had normal height and interval height velocity. The thyroid function remained stable, and the patient attained menarche at age 14. Conclusions: This patient is unique in having asymptomatic, acquired, isolated ACTH deficiency diagnosed in later childhood, despite having frequent sinopulmonary infections since infancy as part of DAVID syndrome. Further research needs to be done to elucidate how NFKB2 variants contribute to acquired, isolated, central ACTH deficiency or autoimmune pituitary disease. Presentation: Thursday, June 15, 2023