The "black fungus" through a gray lens: Imaging COVID-19-associated mucormycosis

View of mucormycosis during the era of COVID-19 infection: A cross-sectional study

Background

During the coronavirus (COVID-19) global pandemic, the diagnosis of mucormycosis co-infection has become challenging as it is sometimes misdiagnosed or even undiagnosed. Many factors contribute to acquiring such infections. These factors vary but their main reason for getting such infections is being immunocompromised. Thus, it results in weak host immunity to fight and prevent such co-infection.

Objectives

This study aims to assess the knowledge perception among the general population in Saudi Arabia regarding black fungus and its relationship with the global pandemic COVID-19.

Materials and Methods

A prospective, qualitative, questionnaire-based cross-sectional study took place. The obtained data were statistically analyzed using SPSS version 21.

Results

The study included 1138 participants, 31.5% from southern region, 27.8% from Eastern region, 22.2% from north region, 12.2% from Western region, and 6.3% from Central region. The participant's mean age was 27.1 ± 11.9 years old. A good knowledge level was detected among 35% of female respondents compared to 28.9% of males with reported statistical significance (P =0.036). All other factors including age, education, and work were insignificantly associated with public knowledge level.

Conclusions

A considerable percentage of the current study population had poor knowledge level of perception and awareness regarding mucormycosis in relation to COVID-19.

Mucormycosis an added burden to Covid-19 Patients: An in-depth systematic review

As of 25th July, 2022, global Disease burden of 575,430,244 confirmed cases and over 6,403,511 deaths have been attributed to coronavirus disease 2019 (COVID-19). Co-infections/secondary infections continue to plague patients around the world as result of the co-morbidities like diabetes mellitus, biochemical changes caused by Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) especially significant elevation in free iron levels, immune suppression caused by SARS-CoV-2, and indiscriminate use of systemic corticosteroids for the treatment of severe COVID-19 disease. In such circumstances, opportunistic fungal infections pose significant challenge for COVID-19 disease therapy in patients with other co-morbidities. Although COVID-19-associated Mucormycosis (CAM) has been widely recognized, currently extensive research is being conducted on mucormycosis. It has been widely agreed that patients undergoing corticosteroid therapy are highly susceptible for CAM, henceforth high index of screening and intensive care and management is need of an hour in order to have favorable outcomes in these patients. Diagnosis in such cases is often delayed and eventually the disease progresses quickly which poses added burden to clinician and increases patient load in critical care units of hospitals. A vast perusal of literature indicated that patients with diabetes mellitus and those with other co-morbidities might be highly vulnerable to develop mucormycosis. In the present work, the case series of three patients presented at Chest Disease Hospital Srinagar, Jammu and Kashmir infected with CAM has been described with their epidemiological data in supplementary section. All these cases were found to be affected with co-morbidity of Diabetes Mellitus (DM) and were under corticosteroid therapy. Furthermore, given the significant death rate linked with mucormycosis and the growing understanding of the diseases significance, systematic review of the literature on CAM has been discussed and we have attempted to discuss emerging CAM and related aspects of the disease.

Rhino-orbital mucormycosis

PURPOSE OF REVIEW

The current article will update and review the clinical and radiological manifestations and management of rhino-orbital mucormycosis (ROM).

RECENT FINDINGS

There has been an increase in cases of ROM worldwide, especially in India. Immunosuppression (especially diabetes mellitus) is a known predisposing risk factor for ROM. Delayed diagnosis and treatment of ROM can be vision or life-threatening. This article reviews the clinical and radiologic features, treatment, and prognosis of ROM with special emphasis on new and emerging therapies.

SUMMARY

ROM is an angioinvasive fungal infection that affects the sinuses and orbits and may present to ophthalmologists. Clinicians should have a high index of suspicion for ROM, especially in patients with poorly controlled diabetes mellitus or other immunosuppression. Corticosteroid treatment (including the recent COVID-19 pandemic) may be a predisposing risk factor for ROM.

Post-COVID-19 acute invasive fungal rhinosinusitis: a systematic radiological approach in the light of clinico-surgical characteristics

Background

The objective is to describe the radiological imaging findings of post-COVID-19 acute invasive fungal rhinosinusitis (AIFRS), being familiar with the wide variety of imaging spectrum, thus raising the suspicion for early diagnosis. Methods: In this retrospective study, we reviewed the imaging findings in 54 patients with proven post-COVID-19 AIFRS who underwent endoscopic/surgical debridement from April 2020 to September 2021. Most of these patients presented with facial or orbital swelling or facial pain. Medical records with a special emphasis on radiological imaging (50 NCCT of the paranasal sinuses and 17 MRIs of the orbit) were reviewed regarding the degree of mucosal disease of sinuses, nasal cavity, and nasopharynx, extra sinus soft tissue infiltration, especially orbital and cerebral extension (parenchymal, cavernous sinus, vascular or neuro-invasion).

Results

We reported findings in 54 patients with post-COVID-19 AIFRS, of whom 30 were men and 24 were women with a mean age of 48.06. Unexpectedly, infiltration of pterygopalatine fossa was found to precede mucosal opacification of sinuses nasal cavity and affection of nasopharynx. Out of 54 patients, 49 showed inflammatory changes involving pterygopalatine fossa, 29.6% of patients showed infiltration of orbital tissues, 22 patients suffered from a fungal invasion of the cavernous sinus and 3 patients had carotid artery involvement.

Conclusions

Imaging findings of AIFRS significantly vary from subtle mucosal thickening of paranasal sinuses, up to orbital and intracranial extension with vascular thrombosis and neuroinvasion. The hallmark inflammatory tissue infiltration into the pterygopalatine fossa and facial soft tissue may precede mucosal disease.

COVID-19, Mucormycosis and Cancer: The Triple Threat-Hypothesis or Reality?

COVID-19 has been responsible for widespread morbidity and mortality worldwide. Invasive mucormycosis has death rates scaling 80%. India, one of the countries hit worst by the pandemic, is also a hotbed with the highest death rates for mucormycosis. Cancer, a ubiquitously present menace, also contributes to higher case fatality rates. All three entities studied here are individual, massive healthcare threats. The danger of one disease predisposing to the other, the poor performance status of patients with all three diseases, the impact of therapeutics for one disease on the pathology and therapy of the others all warrant physicians having a better understanding of the interplay. This is imperative so as to effectively establish control over the individual patient and population health. It is important to understand the interactions to effectively manage all three entities together to reduce overall morbidity. In this review article, we search for an inter-relationship between the COVID-19 pandemic, emerging mucormycosis, and the global giant, cancer.

Resolving the equation between mucormycosis and COVID-19 disease

The COVID-19 patients, both infected and recovered are rapidly contracting mucormycetes infections due to the 'Mucorales' order, under Zygomycetes class of fungi. The mucorales fungi commonly known to exist in our natural surroundings including soil, but the frequency of incidences was never rampant. This sudden spike in infections, is locally known as 'black fungus,' and is affecting various organs, including- eyes, sinuses, nose, brain, skin, intestine, lungs, etc. The severity of situation is ascertainable from the fact that, in certain cases surgical eye/jaws removal persists as the only viable option to avert mortality, as therapeutic interventions are limited. This epidemic situation intrigued experts to investigate the probable reason behind this unpredicted escalation in reported cases, including in recuperated COVID-19 patients, as person-to-person spread of infection is not common. The comparison of physiological parameters in healthy and COVID-19 afflicted patients highlights that the underlying conditions including diabetes mellitus, steroidal therapy, lymphopenia (decreased CD4+ and CD8+ lymphocytes), deregulated cytokine release storm, elevated free iron levels (hemosiderosis) in blood and insulin insensitivity are playing major roles in deteriorating conditions in rarely pathogenic fungal infections. This review is an attempt to explain the rationalities that makes people vulnerable to mucormycetes infection.

Preclinical efficacy and safety of novel SNAT against SARS-CoV-2 using a hamster model

To address the unprecedented global public health crisis due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), we designed and developed a novel antiviral nano-drug, called SNAT (Smart Nano-Enabled Antiviral Therapeutic), comprised of taxoid (Tx)-decorated amino (NH₂)-functionalized near-atomic size positively charged silver nanoparticles (Tx-[NH₂-AgNPs]) that are stable for over 3 years. Using a hamster model, we tested the preclinical efficacy of inhaled SNAT on the body weight, virus titer, and histopathology of lungs in SARS-CoV-2-infected hamsters, including biocompatibility in human lung epithelium and dermal fibroblasts using lactase dehydrogenase (LDH) and malondialdehyde (MDA) assays. Our results showed SNAT could effectively reverse the body weight loss, reduce the virus load in oral swabs, and improve lung health in hamsters. Furthermore, LDH assay showed SNAT is noncytotoxic, and MDA assay demonstrated SNAT to be an antioxidant, potentially quenching lipid peroxidation, in both the human cells. Overall, these promising pilot preclinical findings suggest SNAT as a novel, safer antiviral drug lead against SARS-CoV-2 infection and may find applications as a platform technology against other respiratory viruses of epidemic and pandemic potential.

COVID-19-associated mucormycosis: Evidence-based critical review of an emerging infection burden during the pandemic's second wave in India

Coronavirus Disease 2019 (COVID-19), during the second wave in early 2021, has caused devastating chaos in India. As daily infection rates rise alarmingly, the number of severe cases has increased dramatically. The country has encountered health infrastructure inadequacy and excessive demand for hospital beds, drugs, vaccines, and oxygen. Adding more burden to such a challenging situation, mucormycosis, an invasive fungal infection, has seen a sudden surge in patients with COVID-19. The rhino-orbital-cerebral form is the most common type observed. In particular, approximately three-fourths of them had diabetes as predisposing comorbidity and received corticosteroids to treat COVID-19. Possible mechanisms may involve immune and inflammatory processes. Diabetes, when coupled with COVID-19-induced systemic immune change, tends to cause decreased immunity and an increased risk of secondary infections. Since comprehensive data on this fatal opportunistic infection are evolving against the backdrop of a major pandemic, prevention strategies primarily involve managing comorbid conditions in high-risk groups. The recommended treatment strategies primarily included surgical debridement and antifungal therapy using Amphotericin B and selected azoles. Several India-centric clinical guidelines have emerged to rightly diagnose the infection, characterise the clinical presentation, understand the pathogenesis involved, and track the disease course. Code Mucor is the most comprehensive one, which proposes a simple but reliable staging system for the rhino-orbital-cerebral form. A staging system has recently been proposed, and a dedicated registry has been started. In this critical review, we extensively analyse recent evidence and guidance on COVID-19-associated mucormycosis in India.