A post-COVID-19 Aspergillus fumigatus posterior mediastinitis: Case report

Abstract

Invasive aspergillosis is a life-threatening condition of the immunocompromised, with a low occurrence reported in the immunocompetent. Although usually made by invasive methods, its early diagnosis is the cornerstone of a better prognosis as it yields a timely management and thus a lower mortality risk. Mediastinal invasion by Aspergillus is, like any fungal mediastinitis, uncommon and usually results from a hematogeneous or a contiguous spread, a postoperative fungal infection, a complication of a descending necrotizing fasciitis, or from an esophageal perforation. We report a case of a diabetic patient with a previous history of hospitalization 2 months earlier for a COVID-19 infection, otherwise healthy, presenting with an unresolving dorsal pain. A malignancy was expected but further work-up showed in fine a posterior mediastinitis due to Aspergillus fumigatus. Thus, fungal etiologies are to be included as a differential while diagnosing a posterior mediastinitis even in a relatively immunocompetent patient and with no evident route of entry.

Keywords: Aspergillus fumigatus; COVID-19; pathology; posterior mediastinitis; radiology; surgery.

Figure 1.

(a) CT axial mediastinal view showing subcentimeter and supracentimeter calcified lymph nodes at the paratracheal level. (b) CT sagittal view showing a dense infiltrative retroesophageal prevertebral lesion of the mediastinal adipose tissue extending from T2 till T8.

Figure 2.

(a) T1-weighted sagittal images showing an intermediate signal expanding prevertebral lesion extending from the level of T2 till the level of T9. (b) T2-weighted sagittal images showing the high signal intensity of the lesion. (c) Post Gd-T1W-SPIR sagittal images showing contrast enhancement of the lesion.

Figure 3.

(a) Necrotic tissue. (b) Mycelial filaments within necrotic tissue. (c) and (d) Branched and septated hyphae in favor of Aspergillus infection.

Figure 4.

Progression of the peridural spread measuring 12 mm responsible for a recent spinal cord compression at the level of T6 to T8 with a high signal abnormality on T2-weighted images. The previously reported enhancement as well as the T2-signal abnormality of the vertebral bodies is significantly increased in addition to the prevertebral lesion thickness currently measuring 7.5 mm.