S2.1d Incidence of mixed fungal infections in post-COVID-19 outbreak of Mucormycosis

Abstract

S2.1 Update on Mucormycosis, September 21, 2022, 3:00 PM - 4:30 PM IntroductionPost-COVID-19 rhino orbital mucormycosis has emerged as an important life-threatening complication adding to mortality. Fungal infections are a major health challenge, especially in the immunocompromised.Mucormycosis is a severe, frequently fatal fungal infection that has a unique predisposition to infect patients with diabetes. The most probable reasons for the emergence of these cases could be the extensive use of steroids in the management of coronavirus disease 2019 (COVID-19) patients and extensive dysregulated immune response due to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection. A prompt diagnosis is vital for the effective management of invasive rhino-orbital fungal infections due to their propensity for angioinvasion and destructive spread with brain involvement.Materials and MethodsA total of 150 surgical pathology specimens received with a clinical suspicion of invasive fungal infection during the post-COVID-19 outbreak of mucormycosis were retrieved from the archives of the Department of histopathology. The cases were reviewed for the presence of Aspergillus fruiting bodies by senior pathologists and microbiologists on a multi-headed microscope. The morphological features of the fruiting bodies were noted and correlated with the fungal KOH and culture. The tissue reaction pattern, presence of oxalate crystals, and morphology of the fungal hyphae were also noted in each case showing Aspergillus fruiting bodies.ResultsA total of 8 out of 150 cases (5.3%) showed the presence of Aspergillus fruiting bodies. The histopathological diagnosis given in these 8 cases were—Aspergillus (1), combined Aspergillus and Mucorales (7). Two types of fungal hyphae were noted in all seven cases of combined infection. Granulomatous tissue reaction was noted in two out of seven cases of combined infection. Calcium oxalate crystals were noted in the single case of Aspergillosis and were absent in all cases of mixed infection.ConclusionTo conclude Aspergillus fruiting bodies are found in a small but significant number of cases of post-COVID-19 Rhino-Orbital invasive mold infections so while reporting the surgical specimens with clinical suspicion of post-COVID-19 mucormycosis one should be aware of the possibility of mixed fungal infections and look for Aspergillus fruiting bodies as a tell-tale sign of mixed Mucorales and Aspergillus infection. However, their presence does not estimate the true incidence of mixed fungal infections for which immunohistochemistry and polymerase chain reaction are needed.