Mucormycosis in COVID-19 pandemic: study at tertiary hospital in India

Infectious disease for the rhinologist

PURPOSE OF REVIEW

The purpose of this review is to summarize the recent literature relating to viral, fungal and bacterial infections and their interactions within the sinonasal tract in the past 18 months.

RECENT FINDINGS

Coronavirus disease 2019 (COVID-19)-associated olfactory dysfunction (OD) is variant dependent. Magnetic resonance imaging studies have found greater olfactory cleft opacification and higher olfactory bulb volume in post-COVID-19 OD. Olfactory training remains the mainstay of treatment, while platelet-rich plasma injections and ultramicronized palmitoylethanolamide and luteolin combination oral supplementation have shown early promise.Consensus statements on paranasal sinus fungal balls and acute invasive fungal sinusitis have been released.Studies on the nasal microbiome have reported Staphylococcus and Corynebacterium as the most abundant genera, with higher levels of Staphylococcus and Corynebacterium being found in patients with chronic rhinosinusitis (CRS) and healthy individuals respectively. However, there is conflicting evidence on the significance of biodiversity of the nasal microbiome found in CRS versus healthy patients.

SUMMARY

While the peak of the COVID-19 pandemic is behind us, its sequelae continue to pose treatment challenges. Further studies in OD have implications in managing the condition, beyond those afflicted post-COVID-19 infection. Similarly, more research is needed in studying the nasal microbiome and its implications in the development and treatment of CRS.

Mucormycosis, New Causative Agents, and New Susceptible Populations: Review of Cases in a Tertiary Care Hospital in Iran (2007-2021)

Background

Mucormycosis is an aggressive opportunistic fungal infection that afflicts patients with severe underlying immunosuppression, uncontrolled hyperglycemia and/or ketoacidosis, iron overload, and occasionally healthy patients who are inoculated with fungal spores through traumatic injuries. The epidemiology of mucormycosis has changed after the COVID-19 pandemic, with mucormycosis becoming the most common and the fatal coinfection.

Methods

In a retrospective, cross-sectional study, 82 hospitalized patients with a definite diagnosis of mucormycosis were reported from 2007 to 2021 in a referral, tertiary care center in Tehran, Iran.

Results

The number of post-COVID cases increased 4.6 times per year, with 41.5% of patients admitted during the two years of the pandemic. Mucormycosis was more common in women (57.3%), and the most common underlying diseases were diabetes (43.7%), both COVID-19 and diabetes (23.2%), cancer (11%), rheumatic diseases (7.3%), COVID-19 without other underlying diseases (6.1%), and transplantation (4.9%). Rhino-orbito-cerebral Mucormycosis (54.9%) followed by Sino-orbital infection (23.2%) was the most common presentation. There was a significant relationship between the use of immunosuppressive agents and the development of Mucormycosis (P<0.005) The average mortality was 41.5%, but this ratio decreased to 35% during the pandemic era.

Conclusion

The COVID-19 pandemic caused a 4.6-fold increase in the number of mucormycosis patients, and there was a significant relationship between hyperglycemia, corticosteroid use, and mucormycosis. The death rate during the COVID-19 pandemic has decreased by 6.5%, and during the COVID period, the interval between the arrival of a patient with mucormycosis and the start of the correct treatment was significantly decreased.

Epidemiology of COVID-19-Associated Mucormycosis

Purpose of the Review

To describe the epidemiology and risk factors for Coronavirus disease-19 (COVID-19)-associated mucormycosis (CAM) based on current published literature.

Recent Findings

COVID-19 is associated with an increased risk of secondary infections. Mucormycosis is an uncommon invasive fungal infection that typically affects people with immunocompromising conditions and uncontrolled diabetes. Treatment of mucormycosis is challenging and is associated with high mortality even with standard care. During the second wave of the COVID 19 pandemic, an abnormally high number of CAM cases were seen particularly in India. Several case series have attempted to describe the risk factors for CAM.

Summary

A common risk profile identified for CAM includes uncontrolled diabetes and treatment with steroids. COVID-19-induced immune dysregulation as well as some unique pandemic specific risk factors may have played a role.

A critical appraisal of mucormycosis in COVID- 19 patients in a tertiary care centre in India

Background and Purpose

Morbidity and mortality of opportunistic fungal infections in COVID-19 patients are less studied and defined. The patients receiving immunosuppressive therapy, broad-spectrum antibiotics, corticosteroids, and invasive and non-invasive ventilation are the high-risk groups.

Materials and Methods

The demographic profile as well as clinical and radiological findings of all the patients with COVID-19 suspected of Mucormycosis (MM) were recorded. The tissue samples from all the patients were sent for microbiological (KOH mount and culture) and histopathological analysis for confirmation of MM.

Results

In total, 45 COVID-19 patients suspected of MM were included in the study and MM was confirmed in 42 patients. The mean age of the patients was 50.30±14.17 years with a female: male ratio of 1.1:1. The most common symptom was headache (52.38%) followed by purulent nasal discharge (38.09%) and facial pain in 33.33% of the cases. The ocular symptoms included a diminution of vision (33.33%) and redness of the eye (2.38%). The most common site of involvement was rhino-orbital (42.85%) followed by sinonasal (23.80%) and rhino cerebral (19.04%). Majority (38.09%) of the patients were diagnosed with stage II of Rhino-orbital-cerebral Mucormycosis (ROCM) based on radiology. A history of diabetes mellitus and steroids was present in 97.61% and 85.71% of the cases, respectively. Moreover, KOH was positive for MM in 97.61% of the cases while the culture was positive in only 35.71% of the cases. In addition, on histopathology, MM was confirmed in 64.28 % of the cases. Mixed growth with Aspergillus species and Rhizopus species was observed in 14.28% of the cases in culture and 11.90% of the cases in histopathology test. Furthermore, angioinvasion was found in 23.80% of the cases according to the histopathology test.

Conclusion

Based on the results, the most common conditions associated with MM in COVID-19 patients were diabetes mellitus and steroid therapy. A high level of clinical suspicion aided with diagnostic tests, including KOH mount, culture, histopathology, and radiology which helped the early detection of opportunistic fungal infection in COVID-19 patients to ensure timely treatment.

COVID-19-Associated Mucormycosis: A Matter of Concern Amid the SARS-CoV-2 Pandemic

Mucormycosis is an invasive fungal infection caused by fungi belonging to order Mucorales. Recently, with the increase in COVID-19 infections, mucormycosis infections have become a matter of concern globally, because of the high morbidity and mortality rates associated with them. Due to the association of mucormycosis with COVID-19 disease, it has been termed COVID-19-associated mucormycosis (CAM). In the present review, we focus on mucormycosis incidence, pathophysiology, risk factors, immune dysfunction, interactions of Mucorales with endothelial cells, and the possible role of iron in Mucorales growth. We review the limitations associated with current diagnostic procedures and the requirement for more specific, cost-effective, convenient, and sensitive assays, such as PCR-based assays and monoclonal antibody-based assays for the effective diagnosis of mucormycosis. We discuss the current treatment options involving antifungal drug therapies, adjunctive therapy, surgical treatment, and their limitations. We also review the importance of nutraceuticals-based therapy for the prevention as well as treatment of mucormycosis. Our review also highlights the need to explore the potential of novel immunotherapeutics, which include antibody-based therapy, cytokine-based therapy, and combination/synergistic antifungal therapy, as treatment options for mucormycosis. In summary, this review provides a complete overview of COVID-19-associated mucormycosis, addressing the current research gaps and future developments required in the field.