Adrenal Histoplasmosis and Tuberculosis: Clinical Presentations and a High Prevalence of Adrenal Insufficiency

Objective: Adrenal infections can lead to adrenal insufficiency (AI). Commonly reported pathogens are Histoplasma capsulatum and Mycobacterium tuberculosis (TB), which can cause similar clinical presentations, yet require different specific treatments. We aim to evaluate clinical presentations, imaging characteristics, and AI prevalence in adrenal infections caused by these pathogens. Designs: Retrospective study. Patients: Thirty-five patients with microbiologically confirmed adrenal histoplasmosis and TB at two referral centers in Bangkok, Thailand. Results: Thirty-one patients (88.5%) had adrenal histoplasmosis, 3 (8.5%) had adrenal TB, and 1 (3.0%) had coinfection. Most patients were non-HIV (97%) males (91%), with a mean age of 64 years. Common symptoms were anorexia and weight loss (91%), with 26% presenting with adrenal crisis. Extra-adrenal infections occurred in 45% of histoplasmosis, 67% of TB, and 100% of coinfections, with 10% of adrenal histoplasmosis patients having concurrent extra-adrenal TB infection. Bilateral adrenal abnormalities were seen in 91%, and all patients with unilateral lesions later developed contralateral involvement. Adrenal lesions ranged from enlargement to mass sized 9.8 cm. The prevalence of AI was 74% (histoplasmosis 73%, TB and coinfection 100%). Over a median follow-up of 22 months, all patients with AI remained on glucocorticoid supplements. Conclusion: Adrenal histoplasmosis and TB primarily affected non-HIV males. Most patients presented with bilateral adrenal masses. The prevalence of AI was high and likely persistent despite specific treatment. Extra-adrenal infections were common in TB and coinfection but were insufficient to determine adrenal infection etiology, highlighting the need for tissue diagnosis.