A case of COVID-19-associated rhino-orbito-cerebral mucormycosis caused by Apophysomyces variabilis with a review of the literature

Rhinocerebral mucormycosis in immunocompetent patients: a case report and review of literature

INTRODUCTION

Mucormycosis of the head and neck region is a rare but aggressive fungal infection that usually involves immunocompromised patients. More infrequently, this infection can also occur in people with no otherwise known underlying immunological deficit. This rarity usually causes a delay in diagnosis and may severely decrease the chance of survival in these patients. In this study, we present an extreme case of mucormycosis in an immunocompetent patient. By conducting a thorough review of the literature, we aim to increase our knowledge on this matter. Our goal is to improve diagnosis and start treatment at an earlier stage.

CASE PRESENTATION AND METHODS

Our patient was a 31-year-old man who presented with bilateral face numbness, neck pain, headache, and a necrotic palatal lesion 45 days after a dental root canal procedure. There was extensive involvement of facial and skull base bony and soft tissues. Through two debridement sessions and intravenous antifungal treatment, the patient was discharged with near-complete disease resolution. We identified 48 cases in the literature that matched our study criteria. We searched the current literature for proven cases of mucormycosis in the head and neck region who didn't have any underlying disease. We extracted their data and added the data of our patient. Then, we re-analyzed them using descriptive analysis, chi-square, and binary logistic regression to better understand the different factors for survival and disease burden in these patients.

RESULTS

49 patients were analyzed in this study. The mean age was 46.93 ± 15.75 (min 16 and max78 years old). The most prevalent subsite to be involved was the sino-nasal mucosa, followed by the surrounding soft tissues and the orbit. While both orbit and intracranial tissue involvement differed significantly between surviving and deceased patients, only intracranial tissue involvement could be used to predict survival. The overall survival rate was 91.8%.

CONCLUSION

Although very rare, mucormycosis can occur in immunocompetent patients. Physicians should consider mucormycosis when faced with refractory conditions and unusual symptoms such as exposed bones, facial numbness, headaches, and intractable pain. Complementary imaging (CT scan with or without MRI) and histopathological examination are critical for timely diagnosis or exclusion of this potentially fatal yet treatable disease.

A case of COVID-19-associated mucormycosis due to Lichtheimia ramosa

BACKGROUND

Mucormycosis is a life-threatening invasive fungal infection in immunocompromised and COVID-19 patients.

CASE REPORT

Here, we report a fatal rhino-orbito-cerebral mucormycosis caused by Lichtheimia ramosa, in a 79-year-old diabetic female. She was initially admitted to the hospital for COVID-19 infection and received broad-spectrum antibiotics and corticosteroids. After 1 month, she was admitted again because of persistent headaches and decreased right eye movement when the computed tomography scan showed mucosal thickening and opacification of paranasal sinuses. Microbiological investigations, including culture and direct microscopy, and histopathological findings confirmed the diagnosis of proven mucormycosis. The isolated causal agent was identified as Lichtheimia ramosa by sequencing the entire ITS region of nuclear ribosomal DNA. Despite surgical debridement and administration of liposomal amphotericin B 5 mg/kg/day, the patient's level of consciousness suddenly deteriorated; she was intubated and mechanically ventilated in the ICU and died on the same day.

CONCLUSION

To our knowledge, this is the first worldwide case of COVID-19-associated rhino-orbito-cerebral mucormycosis due to Lichtheimia ramosa.

Case report: COVID-19-associated mucormycosis co-infection with Lomentospora prolificans: The first case and review on multiple fungal co-infections during COVID-19 pandemic

Along with the pandemic COVID-19 spreads, new clinical challenges have emerged in the health care settings, among which there is a high risk of secondary invasive fungal infections with significant mortality. Here, we report a case of invasive fungal rhino orbital sinusitis due to the simultaneous co-infection by Rhizopus oryzae and Lomentospora prolificans, both identified by sequencing, in a 70-year-old Afghanistanian female with COVID-19. The patient was subjected to surgical debridement as well as taking liposomal amphotericin B, voriconazole, and on discharge, her condition was good. As far as we know, this is the first case of co-infection of COVID-19-associated mucormycosis (CAM) and Lomentospora prolificans infection. Multiple fungal co-infections in COVID-19 patients are reviewed.

Microbial and clinical epidemiology of invasive fungal rhinosinusitis in hospitalized COVID-19 patients, the divergent causative agents

Since COVID-19 spread worldwide, invasive fungal rhinosinusitis (IFRS) has emerged in immunocompromised patients as a new clinical challenge. In this study, clinical specimens of 89 COVID-19 patients who presented clinical and radiological evidence suggestive of IFRS were examined by direct microscopy, histopathology, and culture, and the isolated colonies were identified through DNA sequence analysis. Fungal elements were microscopically observed in 84.27% of the patients. Males (53.9%) and patients over 40 (95.5%) were more commonly affected than others. Headache (94.4%) and retro-orbital pain (87.6%) were the most common symptoms, followed by ptosis/proptosis/eyelid swelling (52.8%), and 74 patients underwent surgery and debridement. The most common predisposing factors were steroid therapy (n = 83, 93.3%), diabetes mellitus (n = 63, 70.8%), and hypertension (n = 42, 47.2%). The culture was positive for 60.67% of the confirmed cases, and Mucorales were the most prevalent (48.14%) causative fungal agents. Different species of Aspergillus (29.63%) and Fusarium (3.7%) and a mix of two filamentous fungi (16.67%) were other causative agents. For 21 patients, no growth was seen in culture despite a positive result on microscopic examinations. In PCR-sequencing of 53 isolates, divergent fungal taxons, including 8 genera and 17 species, were identified as followed: Rhizopus oryzae (n = 22), Aspergillus flavus (n = 10), A. fumigatus (n = 4), A. niger (n = 3), R. microsporus (n = 2), Mucor circinelloides, Lichtheimia ramosa, Apophysomyces variabilis, A. tubingensis, A. alliaceus, A. nidulans, A. calidoustus, Fusarium fujikuroi/proliferatum, F. oxysporum, F. solani, Lomentospora prolificans, and Candida albicans (each n = 1). In conclusion, a diverse set of species involved in COVID-19-associated IFRS was observed in this study. Our data encourage specialist physicians to consider the possibility of involving various species in IFRS in immunocompromised and COVID-19 patients. In light of utilizing molecular identification approaches, the current knowledge of microbial epidemiology of invasive fungal infections, especially IFRS, may change dramatically.