University of Oklahoma Health Sciences Center Oklahoma City, OK, United States
Mahum Nadeem, MD1, Evgeny Idrisov, MD1, Gina Moon, MD1, Ravindranauth Sawh, MD2, Allan Weston, MD, FACG2 1University of Oklahoma Health Sciences Center, Oklahoma City, OK; 2Oklahoma City VA Medical Center, Oklahoma City, OK
Introduction: Histoplasmosis, a fungal infection caused by Histoplasma microconidia found in soil enriched with nitrogen from bird and bat droppings. Vast majority of patients develop subclinical, self-limiting disease, unless they are immunocompromised. We present a rare case of histoplasmosis presenting as adrenal insufficiency and adrenal mass mimicking adrenal malignancy.
Case Description/Methods: 78-year-old male with history of gastroesophageal reflux disease and type II DM, who presented with 2 months history of worsening fatigue, weight loss, and night sweats. CT scan of abdomen and pelvis demonstrated hepatosplenomegaly and bilateral adrenal masses (A, B) with radiological features concerning for adrenal malignancy. Workup was negative for pheochromocytoma, normal renin, serum electrolytes, AM cortisol, and DHEAS levels. Further investigations revealed low plasma aldosterone levels along with ACTH stimulation test concerning for adrenal insufficiency. He was treated with fludrocortisone and hydrocortisone by endocrinology. Subsequently, he underwent EUS-guided biopsy of left adrenal gland. Endoscopic ultrasound demonstrated a 4.2 x 3.2 mm left adrenal heterogenic, hypoechoic mass with predominantly solid and with few small non-echoic, necrotic and hyperechoic areas (C, D). Biopsy showed numerous yeasts with narrow-based budding pathognomic for Histoplasma on GMS stain (E). Later, urine and serum Histoplasma antigen also came back positive confirming the diagnosis. He was treated with amphotericin B and transitioned to itraconazole 200mg daily. On follow up, patient is doing well and has repeat imaging pending.
Discussion: Clinically significant histoplasmosis most commonly involves the lungs, presents with respiratory symptoms and radiographic abnormalities mimicking community-acquired pneumonia. Symptoms of disseminated histoplasmosis are nonspecific (fever, fatigue, malaise, anorexia, weight loss) and can represent a diagnostic challenge. In immunocompetent individuals, adrenal glands are rarely involved. Gold standard for diagnosis of suspicious adrenal mass is biopsy, tissue culture and staining after ruling out pheochromocytoma. Definitive treatment includes liposomal amphotericin B followed by itraconazole. Although rare, disseminated adrenal histoplasmosis should be considered as a differential diagnosis in immunocompetent patient presenting with adrenal mass due to significant mortality and concerns for adrenal insufficiency.
Figure: A.B: CT scan abdomen pelvis showing bilateral adrenal masses C.D: EUS images showing left adrenal mass F: Cell block section containing clusters of yeasts (size 2-4 microns) showing narrow-based budding (arrow) compatible with Histoplasma species (GMS stain X600)
Disclosures: Mahum Nadeem indicated no relevant financial relationships. Evgeny Idrisov indicated no relevant financial relationships. Gina Moon indicated no relevant financial relationships. Ravindranauth Sawh indicated no relevant financial relationships. Allan Weston indicated no relevant financial relationships.
Mahum Nadeem, MD1, Evgeny Idrisov, MD1, Gina Moon, MD1, Ravindranauth Sawh, MD2, Allan Weston, MD, FACG2. P1742 - Bilateral Adrenal Histoplasmosis Presenting as Adrenal Mass Mimicking Malignancy in an Immunocompetent Patient, ACG 2021 Annual Scientific Meeting Abstracts. Las Vegas, Nevada: American College of Gastroenterology.
