Case Presentation: A 72-year-old-female presented to the ED with an 8-month history of intermittent, progressive, substernal chest pain. EKG showed normal sinus rhythm without ischemic changes and troponin was negative. CT Angiogram showed a moderate pericardial effusion and mild wall thickening of the thoracic aorta concerning for vasculitis. Cardiac MRI showed aortitis with mild pericarditis phlegmonous infiltrate in the subcarinal space. Patient, notably, had recent travel history to Tanzania. Rheumatologic work-up was negative including ANA, c-ANCA, anti-proteinase 3, complement panel, and CCP. Initial infectious work-up was negative including hepatitis panel, HIV, TB Gold, blood cultures, and fungal workup. Patient then had a PET scan which showed findings of a 10cm mediastinal mass that was FDG avid. Bronchoscopy was performed with EBUS and biopsy results were negative for malignancy but showed marked fibrosis with vascular proliferation. Patient was discharged home off of steroids without any real diagnosis despite very thorough workup. Two months later the patient returned to the hospital with a moderate pericardial effusion and persistent chest pain. The lymph node from previous bronchoscopic biopsy showed rare yeast forms highly suspicious for Histoplasmosis. Histoplasma antibodies by complement fixation and immunodiffusion were sent out with suspicion for a rare strain of Histoplasmosis duboisii, found in Africa, and presentation was attributed to disseminated Histoplasmosis. As patient was clinically declining it was important to treat to suspected infection and patient improved with Itraconazole 200mg PO three times a day for three days then 200mg twice daily for 6-12 weeks and prednisone 60mg daily for 2 weeks.

Discussion: Aortitis is a rare cause of substernal chest pain with a diverse clinical presentation. Infectious aortitis is generally categorized into syphilitic or non-syphilitic, with the former becoming increasingly rare with the widespread use of antibiotics. Aortic infection by unusual bacteria and fungi, is extremely rare, with no reliable figures to show prevalence. However, given the patients biopsy findings, pericardial effusion, mediastinal adenopathy, and pulmonary nodules this became our leading diagnosis. The patient’s travel history to Tanzania meant that Histoplasmosis duboisii which is not picked up on our Histoplasmosis antibody tests, and not the generally tested Histoplasmosis capsulatum, was the likely organism, as it is endemic in several regions of Africa.

Conclusions: Infectious aortitis due to histoplasmosis is a rare presentation of chest pain and can be life threatening due to high risk of aneurysm with rupture and dissection. Diagnosis can be challenging given that clinical presentation is variable and nonspecific . It is important to rely on clinical judgement over reliance on laboratory findings as treatment with antifungal therapy must be promptly initiated if clinical suspicion is high and as the fungal biopsy was suggestive of rare strain of Histoplasmosis.