Pulmonary involvement with immunodeficiency: the role of CTLA-4 in the pathogenesis of granulomatous lymphocytic interstitial lung disease (GLILD) – an Italian case report

ABSTRACT
We present the case of a 14-year-old female patient who was referred to us in 2024 due to coughing, widespread dermatitis and frequent episodes of diarrhea.
Her medical history included atopic dermatitis in childhood. Initial blood tests and diagnostic tests revealed autoimmune hemolytic anemia, widespread lymphadenopathy and splenomegaly. Further diagnostic investigations revealed rounded pulmonary opacities on chest X-ray, so second-level diagnostic tests were performed, which revealed the presence of a mutation in the CTLA-4 gene on genetic analysis, suggesting a form of primary immunodeficiency, leading to a diagnosis of GLILD. Treatment initially involved corticosteroid therapy and the administration of intravenous immunoglobulins. The therapeutic breakthrough came with the introduction of biological therapy with Abatacept, a CTLA-4 signal modulator, which led to remission of the disease.

KEY WORDS
Case report; GLILD; immunodeficiency