(271) Acute Respiratory Failure in Cushing Disease: An Unusual Presentation

Introduction: Cushing's disease, characterized by excessive production of cortisol due to a pituitary adenoma, can lead to a state of immunosuppression. This increases the risk of opportunistic infections, which can complicate the clinical course and management of affected individuals. We present a case of severe respiratory compromise due to opportunistic infections, highlighting the complex interplay between endocrine disorders and infectious diseases.

Description: A 77-year-old male never-smoker with history of congestive heart failure presented with worsening shortness of breath and productive cough over one month. He denied having any sick contacts, fever, chills, hemoptysis, night sweats, or unintentional weight loss. Upon admission, he required 3 liters/minute of oxygen, though other vital signs were stable. Physical examination showed 2+ bilateral lower extremity edema, jugular venous distension, and bibasilar lung crackles. Laboratory tests revealed leukocytosis, a brain natriuretic peptide level of 221 pg/ml, bicarbonate of 34 mmol/L, and potassium of 2.3 mmol/L. Despite treatment with diuretics for decompensated heart failure, the patient remained hypoxic, and his dyspnea worsened.
Imaging studies, including a CT scan, showed tree-in-bud opacities with a nodular density in the right upper lobe, along with bilateral adrenal hypertrophy. Due to high oxygen requirements through a high flow nasal cannula, he was transferred to the intensive care unit. Bronchoscopy with transbronchial biopsies identified Aspergillus and Pneumocystis jirovecii in the bronchial washings, with positive aspergillus galactomannan on bronchoalveolar lavage and tissue pathology showing angio-invasive aspergillus. The patient was started on voriconazole and trimethoprim/sulfamethoxazole.
Further workup revealed elevated cortisol and adrenocorticotropic hormone levels, which were suppressed with high-dose dexamethasone, and an MRI scan of the brain confirmed a pituitary adenoma.

Discussion: Immunocompromised status in Cushing's disease increases susceptibility to infections such as those caused by Aspergillus and Pneumocystis jirovecii, as observed in this patient. Management of such cases requires a multidisciplinary approach, addressing both the underlying endocrine disorder and the associated infections.