Studying the use of a proposed three-level grossing protocol in the histopathological diagnosis of COVID-19-associated rhinomaxillary mucormycosis.

INTRODUCTION: Mucormycosis is an acute and rapidly progressing opportunistic fungal infection. COVID-19-associated mucormycosis (CAM) had re-emerged as a complication of COVID-19 infection during the second wave of the pandemic in 2021. The rhinomaxillary form is a variant of the rhino-cerebral mucormycosis that presents a diagnostic challenge to the dentist and the oral and maxillofacial pathologist. Gross examination of pathological specimens is the most undermined step even though it plays a vital role in the final diagnosis. No studies have described this post-clinical step for the maxillofacial soft and hard tissue submitted for examination.

MATERIAL AND METHODS: A prospective comparative study was carried out on 52 COVID-19-associated rhinomaxillary mucormycosis (CARM) cases to achieve complete, representative, and informative sampling of the submitted tissue and establish a three-level gross macroscopic examination protocol. Complete clinical and radiological histories were recorded after informed, written consent from every patient was received. Details of the number and type of samples received were recorded, grossing procedure was done as per the proposed three-level grossing protocol and were then compared to the presence of fungal hyphae in the soft tissue or decalcified hard tissue.

RESULT: All 100% of the samples consisted of soft tissue (maxillary sinus lining), while 90.4% of the samples contained different hard tissue specimens. Seventy percent of the grossing workload was carried out by first-year oral pathology residents. Sixty-seven point three percent of the total soft tissue samples submitted showed no presence of fungal hyphae, while 69.2% of total decalcified sections of hard tissue were positive for fungal hyphae with a positive correlation. Out of the 29 cases grossed via the three-level grossing protocol, 89.6% of the cases were histopathologically positive for fungal hyphae. Thus a positive association ( P < 0.05) between histopathological diagnosis and the proposed three-level grossing protocol was found.

CONCLUSION: It is imperative to recognise that no mucormycosis report is to be signed out without multi-site (three-level grossed) bone decalcified reports. There is an immediate need to realise how vital documentation, correct laboratory practices, and grossing are for accurate histopathological diagnosis.