Current Understanding in the Pathophysiology of SARS-CoV-2-Associated Rhino-Orbito-Cerebral Mucormycosis: A Comprehensive Review

Risk Factors Associated with Mortality in Patients with Mucormycosis Post Severe Acute Respiratory Syndrome Coronavirus-2 (Sars-Cov-2) Infection

To study the potential risk factors associated with mortality in patients with mucormycosis. A retrospective study of 490 patients with diagnosis of sinonasal mucormycosis was done. They were divided in two groups-Group A included 87 patients that expired during the study period and Group B included 403 control patients. All the demographic, clinical and outcome parameters were collected from the patient's record files and noted in a structured case proforma and were analysed. During the mean hospital stay of 22 ± 6 days, 17.7% patients expired during the treatment course. Multiple risk factors like uncontrolled diabetes, dyselectrolytemia, underlying renal disease and extensive nature of the disease involving orbit, intracranium and with pulmonary dissemination, all were associated with high mortality in Mucormycosis. Early recognition and appropriate management of the secondary factors can grossly reduce the risk of mortality in patients with mucormycosis.

Comprehensive Review on the Virulence Factors and Therapeutic Strategies with the Aid of Artificial Intelligence against Mucormycosis

Mucormycosis, a rare but deadly fungal infection, was an epidemic during the COVID-19 pandemic. The rise in cases (COVID-19-associated mucormycosis, CAM) is attributed to excessive steroid and antibiotic use, poor hospital hygiene, and crowded settings. Major contributing factors include diabetes and weakened immune systems. The main manifesting forms of CAM─cutaneous, pulmonary, and the deadliest, rhinocerebral─and disseminated infections elevated mortality rates to 85%. Recent focus lies on small-molecule inhibitors due to their advantages over standard treatments like surgery and liposomal amphotericin B (which carry several long-term adverse effects), offering potential central nervous system penetration, diverse targets, and simpler dosing owing to their small size, rendering the ability to traverse the blood-brain barrier via passive diffusion facilitated by the phospholipid membrane. Adaptation and versatility in mucormycosis are facilitated by a multitude of virulence factors, enabling the pathogen to dynamically respond to various environmental stressors. A comprehensive understanding of these virulence mechanisms is imperative for devising effective therapeutic interventions against this highly opportunistic pathogen that thrives in immunocompromised individuals through its angio-invasive nature. Hence, this Review delineates the principal virulence factors of mucormycosis, the mechanisms it employs to persist in challenging host environments, and the current progress in developing small-molecule inhibitors against them.

Maxillary Mucormycotic Osteonecrosis as a Manifestation of Post-COVID-19 Infection in Non-diabetic Patients: Report of Two Cases

Mucormycosis is a rare, opportunistic fungal infection prevalent in the elderly, especially in patients with uncontrolled diabetes or a compromised immune system. However, the outbreak of the pandemic declared by the World Health Organization in late 2019 increased the incidence of mucormycosis cases in COVID-19 patients due to increased steroid usage that resulted in an immunocompromised state. The current report presents two cases of oral mucormycotic osteomyelitis in patients who developed diabetes post-COVID infection, along with a review and relevant literature.

Oculoplastic Conditions in Covid-19 Patients: Case Series and Literature Review

Purpose

To investigate oculoplastic conditions in patients diagnosed with coronavirus disease 2019 (COVID-19) seen at ophthalmology departments of three tertiary referral centers in the United Kingdom and the United States, and review of the literature.

Methods

Retrospective multicenter case series studied over 18 months.

Results

A total of four patients developed eyelid, orbital, or lacrimal gland pathology within four weeks of testing positive for COVID-19. All were male, and the mean age at presentation was 49 (range, 31-58 years). Suspected diagnoses included anterior idiopathic orbital inflammation, facial angioedema, dacryoadenitis, and anophthalmic socket inflammation. Three patients recovered fully and one patient recovered partially (mean 2.7 weeks) from ocular manifestations with steroids hastening recovery.

Conclusion

Adnexal manifestations of COVID-19 include self-limiting orbital inflammation and eyelid lymphedema.

Association of COVID with Mycosis in General

BACKGROUND

The COVID-19 pandemic caused by SARS-CoV-2 is a respiratory disease which created havoc worldwide, was accompanied by another peculiar, otherwise rare, secondary fungal infection Mucormycosis which was observed at exceptionally high incidence in India during the second wave of COVID-19. The article explores possible links between the two infectious diseases to understand a higher-than-normal occurrence of Mucormycosis in COVID-19 patients. Coronavirus enters the patients through ACE-2 and many other receptors like- NRP-1, TfR, CD-126, and CD-26. Virus bind to cells possessing these receptors and affect their proper functioning, disturbing homeostatic metabolism and resulting in conditions like hyperglycemia, Diabetic Ketoacidosis (DKA), low serum pH, iron overload, anemia, hypoxia, and immunosuppression as explained in the article. All these outcomes provide a very supportive environment for the attack and spread of Mucormycosis fungi. The major receptor for Mucormycosis in humans is the GRP-78. Its expression is upregulated by coronavirus entry and by hyperferritinemia, hyperglycemia, and acidic conditions prevalent in COVID patients, thus providing an easy entry for the fungal species. Upregulation of GRP-78 furthermore damages pancreatic β-cells and intensifies hyperglycemia, showing quite a synergic relationship. Inordinate rise of Mucormycosis cases in India might be explained by facts like- India possessing a large proportion of diabetic patients, emergence of a very deadly strain of coronavirus- Delta strain, higher doses of steroids and antibodies used to treat patients against this strain, overburdened health care services, sudden much higher need of oxygen supply and use of industrial oxygen could explain the Mucormycosis outbreak observed in India during the second wave of COVID-19.

OBJECTIVE

The present review discusses the functional interdependence between COVID-19 and Mucormycosis and summarizes the possible synergic links between COVID and Mucormycosis.

CONCLUSION

The receptors and metabolic pathways affected by COVID-19 result in severe physiological conditions- hyperglycemia, DKA, anemia, iron overload, immunosuppression, and hypoxia. All these conditions not only increase the expression of GRP-78, the major receptor for entry of fungi but also play a crucial role in providing quality media for Mucormycosis fungus to establish and grow. Hence explains the fungal epidemic observed in India during the second wave of COVID-19 in India.

Role of histopathology in severity assessments of post-COVID-19 rhino-orbital cerebral mucormycosis - A case-control study

BACKGROUND

There was an upsurge in rhino-orbital-cerebral mucormycosis (ROCM) during the second wave of the COVID-19 pandemic in India. Histopathological examination of the biopsies witnessed greater tissue invasion in these cases. The present study aimed to evaluate the histopathological scoring system in the severity assessment and to compare the scores between ROCM that required orbital exenteration (cases) and those that were treated conservatively (controls).

MATERIAL AND METHODS

A retrospective study was conducted to analyze the histopathological features using a scoring system in patients diagnosed with mucormycosis on sino nasal biopsies. The scoring was based on the following parameters: the extent of necrosis (score 1 <50% and score 2 >50%), degree of angioinvasion (score 1 <3 vessels in 10 fields and score 2 > 3 vessels in 10 fields), degree of inflammation (mild, moderate or severe), and fungal load(score 1 to 4), based on which three grades (I to III) were given. The scores were compared between the case group and the control group. The data obtained were analyzed statistically.

RESULTS

The study included 40 controls and 10 cases. The median age of patients in the control group was 52 with 82.5%males (n = 43) and 17.5 % females (n = 7) while in the case group, the median age was 51 years, and all were males. The predominant inflammatory response was of mixed suppurative type (70 %, n = 28). The degree of necrosis was scored 2 in 57.5 % (n = 23) of controls and 70 %(n = 7) in the case group. All the samples in the case group showed scores of 2 for angioinvasion and scores of 3 and 4 for fungal load. There was a statistically significant difference in the degree of necrosis, angioinvasion, the severity of neutrophilic infiltrates, and fungal load between the cases and controls (p-value <0.05).

CONCLUSION

The present study analyses the predictive role of histopathology in invasive mucormycosis. Higher fungal load, degree of angioinvasion, and the absence of granulomas are associated with advanced disease in sinonasal mucormycosis. The study findings recommend incorporating the histopathological scoring criteria in evaluating patients with sinonasal mucormycosis.

Prosthodontic Rehabilitation's Role in Alleviating Anxiety and Depression in Mucormycosis-Induced Maxillectomy Patients Post-COVID-19

BACKGROUND The aim of this study was to assess the influence of maxillofacial prosthodontic rehabilitation on anxiety/depression severity in patients with rhino-orbital cerebral mucormycosis (ROCM) after maxillectomy. MATERIAL AND METHODS Sixty post-mucormycotic patients treated with maxillectomy (33 males, 27 females) were divided into 5 groups based on maxillectomy types (unilateral/bilateral, subtotal/total) and treatment given (psychotherapy/obturator/implant/orbital/ocular prosthesis). Anxiety and depression symptoms were assessed using appearance anxiety inventory (AAI) and patient health questionnaire (PHQ9). Data were collected at 4 time intervals [T0 (before prosthesis), T1 (2 weeks after prosthesis), T2 (6 months) and T3 (1 year). Frequency distribution and mean values were determined for individual group/subgroups/total cohort. Differences between groups were determined using one-way ANOVA (single-factor/Friedman's) followed by post hoc correction (Bonferroni) and t test for unequal variance with probability P value being statistically significant at <0.05. RESULTS The mean scores for appearance anxiety were 29.13±4.72 (diagnostic for existing body dysmorphic disorder) at T0, which decreased to 16.88±3.02 at T3 for the total cohort. The differences for the gender-based cohort, its various groups, and respective subgroups were significant (P<0.05) at various time intervals. The mean scores in the total cohort for depression symptom severity were 16.81±4.89 (moderately severe) at T0, which increased to 18.5±4.94 at T1, followed by reduction at T2 (12.0±4.43; moderate) and T3 (7.38±3.37; mild). Gender differences for both variables were found to be statistically significant (P<0.05). CONCLUSIONS Comprehensive rehabilitation that included a diagnosis of psychological symptoms followed by psychotherapeutic/pharmacotherapeutic/prosthodontic intervention reduced the anxiety/depression symptom levels to normal at 1 year.

Glucose metabolism disorder: a potential accomplice of SARS-CoV-2

Globally, 265,713,467 confirmed cases of SARS-CoV-2 (CoV-2), including 5,260,888 deaths, have been reported by the WHO. It is important to study the mechanism of this infectious disease. A variety of evidences show the potential association between CoV-2 and glucose metabolism. Notably, people with type 2 diabetes mellitus (T2DM) and other metabolic complications were prone to have a higher risk of developing a more severe infection course than people who were metabolically normal. The correlations between glucose metabolism and CoV-2 progression have been widely revealed. This review will discuss the association between glucose metabolism disorders and CoV-2 progression, showing the promoting effect of diabetes and other diseases related to glucose metabolism disorders on the progression of CoV-2. We will further conclude the effects of key proteins and pathways in glucose metabolism regulation on CoV-2 progression and potential interventions by targeting glucose metabolism disorders for CoV-2 treatment. Therefore, this review will provide systematic insight into the treatment of CoV-2 from the perspective of glucose metabolism.

Percentage of Th1 and Th17 cells and serum level of IL-17 and IFN-γ cytokines in COVID-19-associated mucormycosis

The considerable number of the 2019 coronavirus disease (COVID-19) patients who developed mucormycosis infections in West and Central Asia urged a need to investigate the underlying causes of this fatal complication. It was hypothesized that an immunocompromised state secondary to the excessive administration of anti-inflammatory drugs was responsible for the outburst of mucormycosis in COVID-19 patients. Therefore, we aimed to study the implication of two major subsets of adaptive immunity T helper (Th)-1 and Th17 cells in disease development. Thirty patients with COVID-19-associated mucormycosis, 38 with COVID-19 without any sign or symptom of mucormycosis, and 26 healthy individuals were included. The percentage of Th1 and Th17 cells in peripheral blood, as well as the serum levels of interleukin (IL)-17 and interferon-gamma (IFN-γ), were evaluated using flow cytometry and ELISA techniques, respectively. Th17 cell percentage in patients with COVID-19-associated mucormycosis was significantly lower than in COVID-19 patients (P-value: <0.001) and healthy subjects (P-value: 0.01). In addition, the serum level of IL-17 in COVID-19 patients was significantly higher than that of healthy individuals (P-value: 0.01). However, neither the frequency of Th1 cells nor the serum level of IFN-γ was different between the study groups. Given the critical role of Th17 cells in the defense against mucosal fungal infections, these findings suggest that low numbers of Th17 and insufficient levels of IL-17 might be a predisposing factor for the development of mucormycosis during or after COVID-19 infection.

Influence of Prosthodontic Rehabilitation Using Zygomatic Implants in Covid 19 Related Mucormycosis (Rhino-Orbital-Cerebral) Maxillectomy Patients Upon Post-Operative Stress, Anxiety and Functional Impairment: A Prospective Cohort Study

Purpose

To determine the influence of prosthodontic rehabilitation using zygomatic implants in partial maxillectomy upon post-operative stress, anxiety and functional impairment, due to covid 19 associated rhino-orbital-cerebral mucormycosis (ROCM).

Patients and Methods

Twenty maxillectomy patients fulfilling study criterion, received zygomatic implants (ZI) (quad zygoma) (ZDI Simpladent, Switzerland) retained/supported complete maxillary denture. Assessment of stress, anxiety, masticatory performance and speech were determined using diurnal salivary cortisol level, Appearance Anxiety Inventory, multiple sieve technique and auditory perception analysis, respectively. Data were recorded at 6 different stages of rehabilitation (after maxillectomy, implant placement, and after prosthesis delivery (1 week, 1 month, 6 months and 1 year)). Demographic data were expressed as frequency distribution, while mean values were used to find differences between various rehabilitation stages using Friedman and chi-square test with statistical significance value at p < 0.05.

Results

Average daily salivary cortisol levels declined from post maxillectomy (22.80 ± 0.902) to 1 year after prosthesis wearing (8.65 ± 0.985), indicating stress reduction after ZI rehabilitation. Mean scores for appearance anxiety reduced from pre-prosthetic rehabilitation (27.350 ± 3.030) to 1 year (8.950 ± 0.887) following prosthesis wearing. Functional parameters for mastication and speech also improved significantly during the course of rehabilitation. All differences between pre-prosthetic to 1-year stage after prosthesis wearing were found to be statistically significant at p < 0.05.

Conclusion

Post ROCM maxillectomy cases after prosthetic rehabilitation using zygomatic implants showed significant improvement in the psychological (stress and anxiety) as well as function (mastication and speech) characteristics. Rehabilitation post ROCM maxillectomy with the present approach of fixed prosthesis using zygomatic implants mitigates deficient mastication and speech. It also impacts positively on patient psychology by decreasing stress and anxiety.

Imaging spectrum, associations and outcomes in acute invasive fungal rhino-ocular-cerebral sinusitis in patients with COVID-19 pneumonia

Background

Coronavirus Disease 2019 (COVID-19) has been speculated to enhance mucormycosis infection due to its immune-altering pathophysiology. Early identification of high-morbidity conditions is crucial for optimal treatment and improved outcomes.

Methods

A retrospective study was conducted on 63 patients with clinical and microbiological evidence of rhino-ocular-cerebral mucormycosis, who had a history of COVID-19 infection. The clinical, demographic, and imaging data were retrieved and analyzed. Descriptive statistics (mean [SD] and frequency [%]) were used to describe important characteristics across audit cycles.

Results

Out of 63 patients, 54 (85.71%) patients had associated comorbidities, with diabetes mellitus being common comorbidity and all patients had received injectable and/or oral corticosteroids. Imaging showed nasal and paranasal sinus, perisinus, maxillary alveolar arch, and hard palate involvement in 62 (98.41%), 33 (52.38%), 5 (7.94%) and 5 (7.94%) patients, respectively. Orbital involvement was seen in 24 (38.10%) patients. Skull base involvement was seen in 11 (17.46%) patients, and intracranial extension of disease was present in 11 (17.46%) patients. A total of 16 patients were on mechanical ventilation, of whom 3 succumbed. The mean (standard deviation [SD]) intensive care unit (ICU) stay was 13.2 days (6.8) for 5 patients who succumbed and 6.4 days (4.6) for 30 patients who survived (P value = 0.008).

Conclusion

Cross-sectional imaging not only provides the extent of disease spread but also plays a vital role in providing a surgical roadmap to treating surgeons and in predicting prognosis in patients with invasive fungal infections.

Isolated Frontal Sinus Mucormycosis Post Covid 19-external Approaches Revisited!

Background

Isolated frontal sinus involvement in mucormycosis is seen very infrequently. Recent technological advances including image guided navigation and angled endoscopes have shifted paradigm towards minimally invasive surgeries. Open approaches are still relevant for the disease of frontal sinus with lateral extension where effective clearance cannot be obtained if approached endoscopically.

Objectives

The objective of this study was to describe the presentation and management of patients of mucormycosis with isolated frontal sinus involvement with help of external approaches.

Materials and methods

The available records of the patients were retrieved and analysed. The literature, the associated contributory clinical features and management techniques were reviewed.

Results

4 patients presented with isolated frontal sinus mucor involvement. 3 out of 4 patients had history of diabetes mellitus (75%). All patients had history of covid-19 infection (100%). 3 out of 4 patients had unilateral frontal sinus involvement and were operated by Lynch Howarth approach. Mean age of presentation was 46 years with male predominance. Bicoronal approach was used in one case with bilateral involvement.

Conclusion

Although conservative endoscopic surgeries are preferred nowadays for frontal sinus clearance but the extensive bony destruction with lateral extension in our series of patients with isolated frontal sinus mucormycosis warranted the need for open procedures.

Is Serum Ferritin an Early Marker for COVID-19-Associated Mucormycosis?

Background Coronavirus disease 2019 (COVID-19) is a hyperinflammatory disease caused by severe acute respiratory syndrome coronavirus 2, which makes critically ill patients susceptible to invasive fungal infections. Invasive fungal infections such as mucormycosis are associated with high morbidity and mortality. This study aimed to determine the serum ferritin levels in COVID-19-associated mucormycosis (CAM) patients and isolate and identify the fungi causing secondary fungal infections in patients with suspected CAM. Methodology This cross-sectional study was conducted from June to September 2021 among CAM patients admitted to Bowring and Lady Curzon Hospital. After obtaining approval from the institutional ethics committee and valid consent, data regarding demographic details, past medical history, and serum ferritin levels, along with other blood investigations, were carefully collected from patients presenting with clinical features of mucormycosis and a history of COVID-19. Samples were examined under a bright field microscope using wet mounts of samples in KOH, cultured on Sabouraud's dextrose agar, and examined under a microscope after staining with lactophenol cotton blue for the isolation and correct identification of fungi. Statistical analysis was done using Microsoft Excel (Microsoft Corp., Seattle, WA, USA) and SPSS version 26.0 (IBM Corp., Armonk, NY, USA). A p-value less than <0.05 was considered statistically significant. Results A total of 95 patients with CAM were included in this study, comprising 70 males and 25 females. The mean age of presentation was 49.83 ± 12.41 years, with 73% males and 26% females. Type 2 diabetes mellitus was noted in 69% of patients, hypertension in 29%, and steroid use in 42%. The mean serum ferritin level was 537.38 ± 468.88 ng/mL. We found a significant association between increased serum ferritin and a history of diabetes. Serum ferritin levels had a statistically significant correlation with samples of patients who were positive for Mucorales under KOH microscopy. The fungal culture showed the growth of Aspergillus, Mucor, Rhizopus, and Candida. The mean value of serum ferritin in patients who showed mucor growth was 842.09 ng/mL. Conclusions We found a significant increase in serum ferritin levels in CAM patients. Ferritin can be used as an early marker for screening mucormycosis in COVID-19 patients. Monitoring patients with elevated serum ferritin levels in severe COVID-19, glycemic control, judicious use of corticosteroids, early diagnosis, and appropriate treatment can aid in better management of the disease.

Management of post-COVID mucormycosis at a tertiary care center in Northern India

Purpose

Our study aims to compile data on the clinical presentation, pathological and radiological findings in cases of post-COVID mucormycosis, and present the management strategy used in our center.

Methods

This is a retrospective cohort observational study based at a tertiary healthcare institution in Northern India. All COVID-positive patients presenting with clinical features of mucormycosis were included in the study. They underwent complete otorhinolaryngeal, medical, and ophthalmological examination after thorough history taking. Biochemical tests, biopsy and imaging studies were done for all the patients. The treatment strategy included a multidisciplinary team approach, that is, intravenous antifungals as well as surgical debridement of necrotic tissue via Modified Denker’s approach or open maxillectomy, and orbital exenteration, if required. Patients were followed up for six months to look for recurrence.

Results

Twenty-three patients were studied, out of which 14 were males and 9 were females. Pathological findings of 13 out of 15 patients, who underwent surgical debridement revealed mucormycosis as a causative agent, received Amphotericin. Aspergillus was found in two cases which received Voriconazole. Eleven out of 20 patients who were treated in our hospital survived. Three patients were lost to follow up. The average hospital stay of discharged patients was 14 days.

Conclusion

Post-COVID mucormycosis was reported at an alarming rate after the second COVID wave in India especially after steroid therapies in diabetic patients. Thus a timely, aggressive, team approach using Modified Denkers or open maxillectomy along with proper intravenous antifungals is the key to survival in such patients.

Post-COVID Mucormycosis Involving Mandible: A Rare Phenomenon

Mucormycosis is a fungal disease involving predominantly the paranasal sinuses and further spreading to the orbit and cerebral regions. It does rarely affect the pulmonary region and gastrointestinal regions. This disease is seen more in a very serious state, where the tissues undergo necrosis and cause huge morbidity and, in some cases, end up being fatal. The disease was common in individuals with an immune-compromised state, thus more commonly presenting in individuals with uncontrolled diabetes. The disease is usually acquired through coming into contact with spores of the fungus Mucormycetes through the nose, and the fungi invade the paranasal regions, colonize, and spread locally with angio-invasion and relying on host ferritin for survival, thereby causing tissue necrosis. The incidence of mucormycosis had increased considerably post-COVID-19 due to host immune factors. This fungus commonly spreads from paranasal regions to the cranial direction through orbit. The spread is rapid, thus needing early medical and surgical intervention. The spread of infection from the paranasal regions to the caudally placed mandible is very rarely seen. In this paper, we present three cases of mucormycosis spreading caudally and involving the mandibular regions.

T-cell dysfunction as a potential contributing factor in post-COVID-19 mucormycosis

BACKGROUND

The second wave of COVID-19 in India was followed by large number of mucormycosis cases. Indiscriminate use of immunosuppressive drugs, underlying diseases such as diabetes, cancers, or autoimmune diseases was thought to be the cause. However, the mortality was not as high as that seen in non-COVID mucormycosis.

OBJECTIVE

To study the detailed characteristics of T-cells for evaluating the underlying differences in the T-cell immune dysfunction in post-COVID and non-COVID mucor patients.

MATERIAL AND METHOD

The study included histopathologically confirmed cases of mucor (13 post-COVID, 13 non-COVID) and 15 healthy individuals (HI). Expression of T-cell activation (CD44, HLADR, CD69, CD38) and exhaustion (CTLA, PD-1, LAG-3 and TIM-3) markers was evaluated by flow cytometry.

RESULTS

All cases showed significant depletion of T-cells compared to HI. Both post-COVID and non-COVID groups showed increased activation and exhaustion as compared to HI. Non-COVID mucor group showed significant activation of CD4+ T cells for HLADR and CD38 (p = .025, p = .054) and marked T-cell exhaustion in form of expression of LAG-3 on both CD4+ T and CD8+ T cells in comparison with post-COVID patients (p = .011, p = .036). Additionally, co-expression of PD-1 & LAG-3 and LAG-3 & TIM-3 on CD8+ T cells was statistically significant in non-COVID mucor patients (p = .016, p = .027).

CONCLUSION

Immunosuppression in non-COVID mucor showed pronounced exhaustion of T-cells in comparison to post-COVID mucor cases implicating T-cell immune dysfunction is much more severe in non-COVID mucor which are in a state of continuous activation followed by extreme exhaustion leading to poorer outcome.

Antifungal Effect of Nanoparticles against COVID-19 Linked Black Fungus: A Perspective on Biomedical Applications

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a highly transmissible and pathogenic coronavirus that has caused a 'coronavirus disease 2019' (COVID-19) pandemic in multiple waves, which threatens human health and public safety. During this pandemic, some patients with COVID-19 acquired secondary infections, such as mucormycosis, also known as black fungus disease. Mucormycosis is a serious, acute, and deadly fungal infection caused by Mucorales-related fungal species, and it spreads rapidly. Hence, prompt diagnosis and treatment are necessary to avoid high mortality and morbidity rates. Major risk factors for this disease include uncontrolled diabetes mellitus and immunosuppression that can also facilitate increases in mucormycosis infections. The extensive use of steroids to prevent the worsening of COVID-19 can lead to black fungus infection. Generally, antifungal agents dedicated to medical applications must be biocompatible, non-toxic, easily soluble, efficient, and hypoallergenic. They should also provide long-term protection against fungal growth. COVID-19-related black fungus infection causes a severe increase in fatalities. Therefore, there is a strong need for the development of novel and efficient antimicrobial agents. Recently, nanoparticle-containing products available in the market have been used as antimicrobial agents to prevent bacterial growth, but little is known about their efficacy with respect to preventing fungal growth, especially black fungus. The present review focuses on the effect of various types of metal nanoparticles, specifically those containing silver, zinc oxide, gold, copper, titanium, magnetic, iron, and carbon, on the growth of various types of fungi. We particularly focused on how these nanoparticles can impact the growth of black fungus. We also discussed black fungus co-infection in the context of the global COVID-19 outbreak, and management and guidelines to help control COVID-19-associated black fungus infection. Finally, this review aimed to elucidate the relationship between COVID-19 and mucormycosis.

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

A fatal case of COVID-19-associated mucormycosis (CAM) affected a 40-year-old woman who was initially admitted to our hospital due to a SARS-CoV-2 infection. Her clinical condition worsened, and she finally died because of respiratory failure, hemodynamic instability, and mucormycosis with invasion into the orbit and probably the brain. According to DNA sequence analysis of the fungus isolated from the patient, Apophysomyces variabilis was involved. This is the first published case of CAM and the third case of mucormycosis due to this mold.

Role of COVID 19 Inflammatory Markers in Rhino-Orbito-Cerebral Mucormycosis: A Case Study in Predisposed Patients at a Designated Nodal Centre

Mucormycosis is a very morbid and potentially life threatening fungal infection. Sudden emergence and rapidly increasing numbers, of an otherwise rare infection in active Corona virus disease 2019 (COVID-19) or recently recovered patients has made us question the cause for this epidemic in India. This retrospective cohort study was done at Government Ear, Nose and Throat (ENT) hospital, Hyderabad, a designated nodal centre for mucormycosis for the state of Telangana, between April 2021 and June 2021. This study included patients with mucormycosis who had a recent history of COVID-19 infection. Potential predisposing factors (diabetes mellitus, history of oxygen and corticosteroids usage) and inflammatory marker values, predominantly deranged in COVID-19 infection (D-dimer and Serum Ferritin) were evaluated. A correlation between the marker values and susceptibility factors was also studied. Majority of these subjects showed elevated serum markers and had one or more of the predisposing factors for COVID-19 associated mucormycosis (CAM). A significant association was found between elevated marker values and susceptibility factors (diabetes, use of oxygen). Contrary to the popular belief, that the inadvertent use of steroids, use of industrial oxygen or elevated blood sugars caused this epidemic, our study concludes that their role is limited to affecting the extent of morbidity/mortality. B.1.1.7 and B.6.117 variants of severe acute respiratory syndrome coronavirus 2 (SARSCoV2), predominant during the second wave in India, facilitated the fungal invasion and spread by altering the gene expression and inducing inflammatory and immunomodulatory changes.

Pathogenesis and Pathology of COVID-Associated Mucormycosis: What Is New and Why

Purpose of Review

There is global increase in the incidence of mucormycosis. However, a sudden increase in the COVID-associated mucormycosis (CAM) was noted, particularly in India, during the second wave of the COVID-19 pandemic. The interplay of factors involved in the pathogenesis is complex. In this review, the influence of pre-existing disease, exaggerated risk factors, altered milieu due to COVID-19 itself and the consequences of its treatment on the host pathogen interactions leading to the disease and morphology of the fungus will be highlighted.

Recent Findings

Hyperglycemia, acidosis, available free iron, lowered host defenses, and the fungal virulence factors promote the growth of Mucorales. There is a high background prevalence of diabetes mellitus (DM) in India. Uncontrolled or undiagnosed DM, COVID-19 itself, and inappropriate administration of corticosteroids in high doses and for prolonged periods result in hyperglycemia. Diabetic ketoacidosis (DKA) and metabolic acidosis due to hypoxia or renal failure contribute to acidic pH and dissociate bound iron from serum proteins. The host defenses are lowered due to COVID-19-induced immune dysregulation, hyperglycemia itself, and administration of corticosteroids and immune suppressants for the treatment of COVID-19. The altered metabolic milieu in the local microenvironment of nose and paranasal sinuses (PNS) promotes specific interaction of glucose-regulated protein-78 (GRP-78) on host cells with spore coat protein homologue (CotH 3) on Mucorales resulting in rhino-orbito-cerebral mucormycosis (ROCM) as the predominant clinical form in CAM. The pathology is extensive soft tissue involvement with angioinvasion and perineural invasion. Melanized hyphae and sporangia were seen on histopathology, which is unique to CAM. While many factors favor the growth of Mucorales in CAM, hyperglycemia, hyperferritinemia, and administration of hyperbaric oxygen result in reactive oxygen species (ROS) and inadequate humidification results in dehydration. Melanization is possibly the adaptive and protective mechanism of Mucorales to escape the unfavorable conditions due to the treatment of COVID-19.

Summary

High background prevalence of DM, inappropriate administration of corticosteroids and immune dysregulation due to COVID-19 favor the growth of Mucorales in CAM. Melanization of Mucorales hyphae and sporangia on histopathology probably represent adaptive and protective mechanism due to the treatment with hyperbaric oxygen with inadequate humidification as well as the metabolic alterations.

Invasive Fungal Infections in Dengue Recovered Patients: A New Phenomenon in the Covid-19 Era

Invasive fungal rhinosinusitis was seen to rise to epidemic levels after the 2nd wave of ongoing Covid pandemic, especially in tropical countries, maximally in India. A similar trend is being observed for cases who have recently recovered from dengue virus infection. Post dengue invasive fungal infection is a new presentation and any associations between it and Covid pandemic need to be studied in detail to help prepare for any complications. 3 patients presented to the out-patient department of E.N.T at a tertiary level teaching hospital in East India with complains similar to rhinosinusitis. These patients were then evaluated and diagnosed to be infected from Mucormycosis and Aspergillosis fungal sinusitis after which they were managed with surgical debridement and systemic antifungal therapy. All had a recent history of recovery from Dengue virus infection and a possible association could be suspected. 3 patients presented with complains of pain over upper jaw with orbital swelling and loss of vision developing over a period of 24 days. Two of them had ulceration of hard palate. They were then subjected to Contrast MRI along with CT scan of the Paranasal sinuses which depicted pansinus involvement with intracranial extension in two patients. These were then planned for diagnostic nasal endoscopies along with biopsies which turned out to be Invasive fungal sinusitis in the form of Aspergillosis and Mucormycosis. All the 3 patients had recent history of recovery from Dengue virus infection and did not have any other co-morbidities. Covid Associated Mucormycosis (CAM) is a well-known entity now but no reports of Dengue associated Invasive fungal sinusitis are yet reported. Whether this new phenomenon has anything to do with the interactions between dengue virus and coronavirus is not known at present and needs to be studied in detail so appropriate management protocols can be formulated.

Evaluation of environmental Mucorales contamination in and around the residence of COVID-19-associated mucormycosis patients

Introduction

Recently, India witnessed an unprecedented surge of coronavirus disease 2019 (COVID-19)-associated mucormycosis (CAM) cases. In addition to patient management issues, environmental Mucorales contamination possibly contributed to the outbreak. A recent study evaluated environment contamination by Mucorales in the hospital setting. However, a considerable number of CAM patients were never admitted to a hospital before the development of the disease. The present study, therefore, planned to evaluate Mucorales contamination of patients’ residences.

Methods

The residential environment of 25 patients with CAM living in north India was surveyed. Air samples were collected from indoor and immediate outdoor vicinity of the patients’ residence and cultured on Dichloran Rose–Bengal Chloramphenicol (DRBC) agar with benomyl for selective isolation of Mucorales. Surface swab samples were also collected from the air coolers fitted in those residences and cultured on DRBC agar. The isolates were identified by phenotypic and genotypic methods. Amplified fragment length polymorphism (AFLP) was employed to evaluate the genetic relatedness of the environmental and patients’ clinical isolates.

Results

The median spore count (mean ± SD, cfu/m3) of Mucorales in the air of patients’ bedrooms was significantly higher than in the air in other rooms in those residences (3.55 versus 1.5, p = 0.003) or the air collected directly from the front of the air cooler (p &lt; 0.0001). The Mucorales spore count in the environment did not correlate with either ventilation of the room or hygiene level of the patients’ residences. Rhizopus arrhizus was isolated from the environment of all patients’ residences (n = 25); other Mucorales species isolated were Cunninghamella bertholletiae (n = 14), Rhizopus microsporus (n = 6), Rhizopus delemar (n = 6), Syncephalastrum racemosum (n = 1), Lichtheimia corymbifera (n = 1), and Mucor racemosus (n = 1). Genetic relatedness was observed between 11 environmental isolates from the patients’ bedrooms and respective clinical isolates from patients.

Discussion

The study supported the view that the patients might have acquired Mucorales from the home environment during the post-COVID-19 convalescence period. Universal masking at home during patients’ convalescence period and environmental decontamination could minimize exposure in those susceptible patients.

Father–Son COVID ‐19‐associated mucormycosis: Important role of genetic susceptibility in combination with environmental factors

In this report, a father with a history of diabetes mellitus and his son without a remarkable past medical history, both got COVID‐19‐ associated mucormycosis (CAM) as evidenced by their clinical and radiological findings. This suggests the possible role of genetics in combination with the environment in susceptibility to CAM.

The simultaneous infection of a diabetic father and his son who did not have any known risk factors for COVID‐19‐associated mucormycosis (CAM) may indicate the possible role of genetics and the environment in CAM infection.

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.

First report of rhino-orbital-cerebral mucormycosis after COVID-19 infection in Bulgaria

Mucormycosis is a relatively rare infection but with a high mortality rate due to the difficult and time-consuming diagnostic and therapeutic process. The authors present the first case of rhino-orbital-cerebral mucormycosis, histologically and microbiologically proven, in a patient after COVID-19 infection in Bulgaria.

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.

COVID ‐19‐associated facial cutaneous mucormycosis superinfection: A potentially life‐threatening disease

A 49‐year‐old male was involved in an accident and an abdominal computer tomographic examination revealed papillary renal cell carcinoma of the right kidney. During hospitalization, the patient was infected with COVID‐19. In the following COVID‐19 treatment, a black dot developed on the right side of the head and face. Antifungal therapy and surgical debridement were initiated and gradual improvement was observed.

COVID‐19 infection is spreading rapidly and mucormycosis is an invasive fungal infection which causes a high rate of mortality. Early diagnosis and prompt treatment can result in better outcome of the patient.

Histomorphological features of mucormycosis with rise and fall of COVID-19 pandemic

Introduction

Due to Corona Virus disease -19, India saw a surge of mucormycosis cases, associated with high death rate. India, during the month of May to July 2021 saw a surge of mucormycosis from all states, with close to 50,000 cases just in a span of 3 months.

Objective

To examine the histopathological appearances of rhino-orbital/rhino-maxillary/sino-nasal mucormycosis in the backdrop of the ongoing COVID 19 pandemic.

Material and methods

The study involved analysis of 60 biopsy samples of suspected rhino-maxillary /rhino-orbital mucormycosis received from post-COVID-19 patients. A preliminary review of the slides showing hyphal forms of fungal organisms with un-doubtful tissue / mucosal invasion was included. All samples were examined under Hematoxylin and Eosin stains along with special fungal stains. Data thus obtained were analyzed statistically. Special stains for fungus namely Periodic Acidic Schiff (PAS) and Gomori Methenamine silver (GMS) were utilized to confirm and/or to differentiate the fungal organisms and to highlight the cell wall of the fungus.

Results

The mean age of the patients with mucormycosis was 51.68 years and 72 (83.33%) of them were males. Acute type of inflammation was noted in 44 (73.33%), granulomatous inflammation in 14 (23.33%) of cases. Bony invasion and perineural invasion was observed in 5 (8.33%) and 55 (91.67%) cases, respectively. The dominant fungus were mucorales in 58 (96.67%), aspergillous, along with mucorales in 12 (20%) and combination of mucorales and candida identified in 8 (13.33%) cases.

Conclusion

Besides all the histological appearance of angioinvasion, bone, and soft tissue invasion, a notable aspect was the shift in inflammatory pattern, which was more granulomatous in nature, with a decrease in fungal load correlating with the drop of COVID second wave. This proves that as immunity develops, the host's response to secondary opportunistic infections changes.

Post-Covid-19 Rhino-Cerebral Mucormycosis: an Observational Study During the Second Wave

Mucormycosis is one of the most lethal and rapidly spreading fungal infection which is caused by fungus of the order Mucorales. The swiftness of spreading and high mortality rate that characterize mucormycosis cases added more burden to the enormous challenge brought by the Covid-19 pandemic globally. The aim of this article is to identify and discuss mucormycosis and review the literature related to its diagnosis and management. A total of 15 mucormycosis cases with a history of Covid-19 infection were identified in the Department of Dentistry of Shri B M Patil Medical College Hospital and Research Centre BLDE (Deemed to be University), Vijayapura, India. The duration of the study was between April 1st and mid-September 2021. Nasal swab and tissue samples from oral and maxillofacial region were collected. Blood investigations, RT-PCR and HbA1c tests and radiography revealed changes in the trabecular pattern and bone loss associated with periodontal inflammation. Mucormycosis is a life-threatening infection. Hence, dental and other clinical professionals must be aware of this possible fatal complication, so as to avoid an unfavorable outcome in clinical practice.

COVID-19 Associated Mucormycosis (CAM): A Single Hospital-Based Study

BACKGROUND

Opportunistic fungal infections like Mucormycosis in Coronavirus Disease 2019 (COVID-19) patients have posed a great challenge to health care professionals, especially in developing countries like India. Hence, there is a need to understand the biological behaviour of COVID-19 associated Mucormycosis (CAM) to establish standard treatment Protocols and to reduce mortality.

AIMS

This study aims is to assess the type of Mucormycosis among COVID-19 patients in study population and compare the findings with clinical, radiological and haematological parameters along with treatment and surgical management.

METHODS AND MATERIAL

This retrospective, observational study included 60 cases of CAM reported to the Department of Oral and Maxillofacial Surgery at the tertiary care centre, Karnataka Institute of Medical Sciences, Hubli. Data about various parameters were tabulated and analysed statistically.

STATISTICAL ANALYSIS USED

Bivariate analysis was done using the Chi-Square test to assess the relationship between the type of Mucormycosis and other variables. Spearman's Correlation test was used to assess the correlation between types of Mucormycosis with the other variables. Linear regression analysis was performed to assess the response variable related to the type of Mucormycosis.

RESULTS

About 50% of subjects presented with "Rhino orbital" type of Mucormycosis. Palatal discoloration and palatal erosion was the most common oral manifestation among "only Sinus" and "Rhino orbital" types of Mucormycosis (P = 0.00). Significant association (P = 0.29) was found between the type of Diabetes mellitus and Mucormycosis.

CONCLUSIONS

The study indicates that DM is the most commonly associated comorbidity in CAM patients. Hence, a thorough understanding of the underlying comorbidity and its close monitoring during and after COVID-19 infection is mandatory for successful treatment outcomes.

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.

COVID Induced Functional Exhaustion and Persistently Reduced Lymphocytes as Vital Contributing Factors for Post-COVID Rhino-orbital and Cerebral Mucormycosis in Patients with Diabetes: Report from the Indian Sub-continent

The current pandemic of Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) is a global, unanticipated public health crisis. Another emerging challenge is the prevalence of "black fungus", or mucormycosis, among patients who recovered from COVID-19 infection. A retrospective study was conducted on 12 patients in a post-COVID recovery phase who developed mucormycosis. The study parameters evaluated lymphocyte count, CD4+ T cell status, and associated systemic co-morbidities for the patient, namely diabetes. The interventions during the treatment for COVID were also recorded to include administration of oxygen, ventilator assistance (invasive and non-invasive)/oxygen support, and steroid use. The possible relationship between low lymphocyte and CD4+ counts with diabetes and fungal growth was evaluated. It was observed that the majority of the patients who had a positive history for diabetes with low lymphocyte and CD4+ counts were more susceptible to opportunistic fungal infections. Most of the patients, but not all, had a history of receiving oxygen or assisted ventilation, as well as steroids, during the treatment for COVID infection. These interventions may be considered as accessory contributing factors for fungal infection. Post-exposure to SARS-CoV-2, therapies should be targeted at prevention of functional exhaustion of lymphocytes and maintaining optimal lymphocyte and subset counts in susceptible hosts for the prevention of opportunistic fungal infections. The relationship between functional exhaustion of the lymphocyte, diabetes, and COVID mandates further research.

Acute Invasive Fungal Rhinosinusitis and Coronavirus Disease 2019

ABSTRACT

Acute invasive fungal rhinosinusitis (mucormycosis) is a rare, highly fatal disease. This opportunistic fungal infection causes angioinvasion and ischemic tissue necrosis. It mainly affects immunocompromised patients. Since the coronavirus disease 2019 (COVID-19) outbreak, many case reports have described the rhino-orbital-cerebral mucormycosis associated with COVID-19. However, the underlying predisposing factors are unknown. Several factors, other than diabetes, which is the most well-known contributing factor, may be involved in causing this severe fungal infection in COVID-19 patients. These factors may include steroid therapy, which is being used in severely dyspneic patients, the use of broad-spectrum antibiotics that may cause fungal flare-ups, and hospitalization with possible nosocomial infections. In addition, increased serum ferritin levels, possible endothelial damage, and pancreatic islets affection among COVID-19 patients may be implicated. Head and neck surgeons should be aware of the increasing prevalence of craniofacial mucormycosis among COVID-19 patients, as early diagnosis and prompt treatment are essential to improve the outcomes.

Mandibular mucormycosis following SARS-CoV-2 infection - A case report and review of literature

BACKGROUND

The second wave of COVID-19 pandemic has seen an unprecedented rise in the number of mucormycosis cases worldwide and in India particularly. This otherwise rare fungal infection has become an endemic among patients who have recovered from recent SARS-CoV-2 infection. Among the different types of mucormycosis, rhino-orbital-cerebral involvement has mainly been observed in the recent surge of cases. Very few cases of mucormycosis of mandible have been reported in literature and none in COVID-19 patients. We report a case of isolated mandibular mucormycosis in a COVID- 19 patient, with no other predisposing comorbidities.Case report.A 39 year old patient recently recovered from COVID-19 presented with typical symptoms of osteomyelitis which was confirmed using computed tomography of face. He underwent thorough debridement and curettage and tissue was sent for culture, special staining and biopsy.

RESULT

Diagnosis of mucormycosis was confirmed based on postoperative biopsy and special staining. He was further managed with complete course of appropriate antifungal therapy.

CONCLUSION

Mucormycosis is a fulminant and aggressive infection which requires prompt diagnosis and intervention. Early referral to a maxillofacial surgeon by physicians and general dental practitioners on seeing signs and symptoms of secondary fungal infections involving maxilla or mandible in patients with history of SARS-CoV-19 infection can improve prognosis.

Connecting the Dots: Interplay of Pathogenic Mechanisms between COVID-19 Disease and Mucormycosis

Coronavirus disease (COVID-19)-associated mucormycosis (CAM) is an emerging threat globally, especially in India. More than 40,000 CAM cases have been reported in India. The emergence of CAM cases in India has been attributed to environmental, host, and iatrogenic factors. Mucorales spore burden has been reported globally; however, their presence is higher in tropical countries such as India, contributing to the emergence of CAM. Before the COVID-19 pandemic, patients with diabetes mellitus, haematological malignancies, solid organ transplants, corticosteroid therapy and neutropenia were more prone to mucormycosis, whereas in COVID-19 patients, virus-induced endothelial dysfunction, hyperglycaemia, and immune dysfunction following corticosteroid use increase the risk of acquiring mucormycosis. The interaction of Mucorales spores with the epithelial cells, followed by endothelial invasion, is a crucial step in the pathogenesis of mucormycosis. Endothelial damage and increased endothelial receptor expression induced by COVID-19 infection may predispose patients to CAM. COVID-19 infection may directly induce hyperglycaemia by damaging beta cells of the pancreas or by corticosteroid therapy, which may contribute to CAM pathogenesis. Iron acquisition from the host, especially in diabetic ketoacidosis (DKA) or deferoxamine therapy, is an important virulence trait of Mucorales. Similarly, the hyperferritinaemia caused by COVID-19 may act as a source of iron for Mucorales growth and invasion. In addition, corticosteroid treatment reduces or abolishes the innate immune functions of phagocytic cells contributing to the pathogenesis of CAM. This review aims to discuss primarily the host and iatrogenic factors shared between COVID-19 and mucormycosis that could explain the emergence of CAM.