A case of pulmonary pseudallescheriasis presenting as a fungal ball in a bronchiectasis patient

SESSION TITLE: Chest Infections Case Report Posters 33 SESSION TYPE: Case Report Posters PRESENTED ON: 10/11/2023 12:00 pm - 12:45 pm INTRODUCTION: Pseudallescheria boydii is an emerging opportunistic filamentous fungus recognized as a rare etiologic agent of severe lung infections, particularly in those immunocompromised or with structural lung disease. Due to clinical rarity, a paucity of consensus exists in the management of this life-threatening disease. CASE PRESENTATION: A 44-year-old woman with type 2 diabetes presented with an incidental radiographic finding of bronchiectasis and sputum positivity for Mycobacterium abscessus (Fig 1). A high-resolution computed tomography (CT) was performed to further characterize her bronchiectasis which showed extensive bibasilar varicoid and cystic bronchiectasis and an incidental finding of a pulmonary mycetoma (Fig 2). Subsequent bronchoalveolar lavage (BAL) fluid culture identified Pseudallescheria boydii, and notably negative Aspergillus cultures and galactomannan assay, confirming the diagnosis of pulmonary pseudallescherioma.As has been previously done in our center [1], endobronchial resection of the mycetoma was attempted but this was not feasible due to severe inflammation around the cavity. Surgical opinion was sought but she was deemed high risk for postoperative complications due to the concomitant M. abscessus infection. As such, we opted for medical therapy using oral voriconazole 200 mg twice daily.Repeat BAL fluid cultures obtained 6 months into antifungal therapy did not isolate P. boydii. She completed 18 months of oral voriconazole before switching to long-term suppressive therapy with oral itraconazole 200 mg twice daily. Follow-up CT after one month of itraconazole showed stable mycetoma with no further invasion into the parenchyma (Fig 3). DISCUSSION: Clinical manifestation of pulmonary pseudallescheriasis is non-specific and often mirrors aspergillosis, from asymptomatic colonization of the airways to locally invasive mycetoma, and in severe cases, disseminated infections in the body [2]. Although surgical or endobronchial resection of mycetoma is regarded as the gold standard therapy, it may not be feasible for patients with medical comorbidities. For such patients, long-term antifungal therapy should be initiated as an alternative wherein accepted regimens include newer triazoles such as voriconazole, with itraconazole and echinocandins showing promising antifungal activity against P. boydii [3]. In our case, a 6-month voriconazole monotherapy successfully suppressed the fungal infection. However, with considerable risk of recurrence and progression to disseminated disease, we elected a long-term, and likely lifelong, suppressive therapy on itraconazole with more favorable side effect profile. CONCLUSIONS: Pulmonary pseudallescheriasis is an emerging fungal infection associated with high mortality. With the rise in pulmonary fungal diseases post-COVID-19, a timely recognition and appropriate management of pulmonary pseudallescheriasis is more critical than ever. REFERENCE #1: 1. Stather DR, Tremblay A, Dumoulin E, et al. A Series of Transbronchial Removal of Intracavitary Pulmonary Aspergilloma. The Annals of Thoracic Surgery. 2017;103(3):945-950. doi:10.1016/j.athoracsur.2016.08.069 REFERENCE #2: 2. Cortez KJ, Roilides E, Quiroz-Telles F, et al. Infections Caused by Scedosporium spp. Clin Microbiol Rev. 2008;21(1):157-197. doi:10.1128/CMR.00039-07 REFERENCE #3: 3. Lackner M, de Hoog GS, Verweij PE, et al. Species-Specific Antifungal Susceptibility Patterns of Scedosporium and Pseudallescheria Species. Antimicrob Agents Chemother. 2012;56(5):2635-2642. doi:10.1128/AAC.05910-11 DISCLOSURES: No relevant relationships by Elaine Dumoulin No relevant relationships by Dina Fisher No relevant relationships by Chanhee Seo No relevant relationships by Christina Thornton