Bronchiectasis in a patient with Autoimmune Polyendocrinopathy-Candidiasis-Ectodermal Dystrophy: a case report.

Background: The rare monogenic syndrome Autoimmune Polyendocrinopathy-Candidiasis-Ectodermal Dystrophy (APECED) leads to multisystemic autoimmunity with possible lung involvement. Autoimmune pneumonitis is a rare manifestation, with bronchiectasis being the most frequent radiologic pattern, and may lead to fatal outcome. The Sardinian population in Italy has a high incidence of APECED, although no case of lung manifestation has been reported yet in this cohort. This is the case of a Sardinian APECED patient referred to a bronchiectasis clinic. Our aim is to raise awareness and screen these patients earlier for pulmonary involvement and to initiate multidisciplinary treatment for better outcome.

Case presentation: A 49-year-old female native of Sardinia from consanguineous parents was diagnosed with APECED in childhood and was referred to our bronchiectasis clinic in March 2023. In addition to typical APECED features, she reported recurrent respiratory infections since childhood, chronic purulent sputum and a hospitalization for pneumonia. She came to our attention with a recent isolation of P. aeruginosa on sputum culture and diffuse cylindrical and varicoid bronchiectasis on her first CT scan. She underwent aetiologic screening for bronchiectasis with no evidence of another cause of disease. Lung treatment was optimized according to bronchiectasis guidelines, and during follow-up the patient developed methicillin-resistant Staphylococcus aureus (MRSA) infection and M. intracellulare pulmonary disease. The patient was offered P. aeruginosa eradication treatment with intravenous antibiotics and initiation of antimycobacterial therapy.

Conclusion: This is the first documented lung involvement case of APECED in a Sardinian patient, and the first patient reported to enter a bronchiectasis program. The patient was prescribed lung imaging late in time when bronchiectasis complications were already present. Our case report highlights the need for early pulmonary screening and multidisciplinary management in patients with APECED.