Sensitivity of liquid-based cytology in the diagnosis of mucormycosis in COVID-19 treated patients.

Abstract

BackgroundThe coronavirus disease 2019 (COVID‐19) infection caused by the novel severe acute respiratory syndrome corona virus 2 (SARS‐CoV‐2) is associated with a wide range of disease patterns, ranging from mild to life‐threatening pneumonia. COVID‐19 can be associated with a suppressed immune response and/or hyperinflammatory state due to a cytokine storm. Reduced immunity, combined with steroid usage to prevent a cytokine storm along with various pre‐existing comorbidities can prove to be fertile ground for various secondary bacterial and fungal infection, including mucormycosis. Diagnosis of Mucor is a challenging task given the high negativity rate of various detection methods. While histopathology is considered the gold standard, the acquisition of necessary tissue biopsy specimens requires invasive procedures and is time consuming.MethodIn this study five different methods of Mucor detection, namely conventional cytopathology, liquid‐based cytology (LBC, BD SurePath™), potassium hydroxide (KOH) preparation, culture, and histopathology were analysed. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for all five methods.ResultsLBC had values for sensitivity, specificity, PPV, and NPV of 72.4%, 100%, 100%, and 38.4%, respectively, closely matching histopathology in sensitivity (75.9%). The sensitivity of culture, conventional cytopathology, and KOH were very low compared to histopathology and LBC.ConclusionThis study showed that LBC, can be a rapid and effective alternative to histopathology in Mucor diagnosis.