FDG PET-CT imaging of therapeutic response in granulomatous lymphocytic interstitial lung disease (GLILD) in common variable immunodeficiency (CVID)

Abstract

Summary Common variable immunodeficiency (CVID) is the most common severe adult primary immunodeficiency and is characterized by a failure to produce antibodies leading to recurrent predominantly sinopulmonary infections. Improvements in the prevention and treatment of infection with immunoglobulin replacement and antibiotics have resulted in malignancy, autoimmune, inflammatory and lymphoproliferative disorders emerging as major clinical challenges in the management of patients who have CVID. In a proportion of CVID patients, inflammation manifests as granulomas that frequently involve the lungs, lymph nodes, spleen and liver and may affect almost any organ. Granulomatous lymphocytic interstitial lung disease (GLILD) is associated with a worse outcome. Its underlying pathogenic mechanisms are poorly understood and there is limited evidence to inform how best to monitor, treat or select patients to treat. We describe the use of combined 2‐[(18)F]‐fluoro‐2‐deoxy‐d‐glucose positron emission tomography and computed tomography (FDG PET‐CT) scanning for the assessment and monitoring of response to treatment in a patient with GLILD. This enabled a synergistic combination of functional and anatomical imaging in GLILD and demonstrated a widespread and high level of metabolic activity in the lungs and lymph nodes. Following treatment with rituximab and mycophenolate there was almost complete resolution of the previously identified high metabolic activity alongside significant normalization in lymph node size and lung architecture. The results support the view that GLILD represents one facet of a multi‐systemic metabolically highly active lymphoproliferative disorder and suggests potential utility of this imaging modality in this subset of patients with CVID.

Autoimmunity/inflammation in a monogenic primary immunodeficiency cohort

“…Prednisolone monotherapy appears ineffective at long‐term control of AI/I conditions in PID. Organ‐specific AI/I disease in PID often requires additional immunosuppression, such as rituximab and mycophenolate in pulmonary disease to produce a clinical benefit 47 , 48 . Therefore, when considering therapeutic immunosuppression it appears that the site/tissue effected by AI/I should influence treatment choices.…”

The broad spectrum of lung diseases in primary antibody deficiencies

“…In a recent study, the use of fluorodeoxyglycose (FDG)-positron emission tomography/computed tomography (PET/CT) scanning has also been shown to be helpful in assessing and monitoring the response to treatment in CVID patients with GLILD [122]. Compared to HRCT, this technique has less morphologic power but can provide information on extrapulmonary involvement.…”

Infectious and Noninfectious Pulmonary Complications in Patients With Primary Immunodeficiency Disorders

“…In a recent study [112], positron emission tomography (PET)-CT scanning using fludeoxyglucose was used to assess and monitor the response to treatment in CVID patients with GLILD. The authors found a widespread and high level of metabolic activity in the lungs and lymph nodes, thus suggesting the potential utility of this imaging modality in this subset of patients.…”