Is there an association between zinc and COVID-19-associated mucormycosis? Results of an experimental and clinical study

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.

Immune and metabolic perturbations in COVID-19-associated pulmonary mucormycosis: A transcriptome analysis of innate immune cells

BACKGROUND AND OBJECTIVES

The mechanisms underlying COVID-19-associated pulmonary mucormycosis (CAPM) remain unclear. We use a transcriptomic analysis of the innate immune cells to investigate the host immune and metabolic response pathways in patients with CAPM.

PATIENTS AND METHODS

We enrolled subjects with CAPM (n = 5), pulmonary mucormycosis (PM) without COVID-19 (n = 5), COVID-19 (without mucormycosis, n = 5), healthy controls (n = 5) without comorbid illness and negative for SARS-CoV-2. Peripheral blood samples from cases were collected before initiating antifungal therapy, and neutrophils and monocytes were isolated. RNA sequencing was performed using Illumina HiSeqX from monocytes and neutrophils. Raw reads were aligned with HISAT-2 pipeline and DESeq2 was used for differential gene expression. Gene ontology (GO) and metabolic pathway analysis were performed using Shiny GO application and R packages (ggplot2, Pathview).

RESULTS

The derangement of core immune and metabolic responses in CAPM patients was noted. Pattern recognition receptors, dectin-2, MCL, FcRγ receptors and CLEC-2, were upregulated, but signalling pathways such as JAK-STAT, IL-17 and CARD-9 were downregulated; mTOR and MAP-kinase signalling were elevated in monocytes from CAPM patients. The complement receptors, NETosis, and pro-inflammatory responses, such as S100A8/A9, lipocalin and MMP9, were elevated. The major metabolic pathways of glucose metabolism-glycolysis/gluconeogenesis, pentose phosphate pathway, HIF signalling and iron metabolism-ferroptosis were also upregulated in CAPM.

CONCLUSIONS

We identified significant alterations in the metabolic pathways possibly leading to cellular iron overload and a hyperglycaemic state. Immune responses revealed altered recognition, signalling, effector functions and a pro-inflammatory state in monocytes and neutrophils from CAPM patients.

An extensive review on antifungal approaches in the treatment of mucormycosis

During the period of COVID-19, the occurrences of mucormycosis in immunocompromised patients have increased significantly. Mucormycosis (black fungus) is a rare and rapidly progressing fungal infection associated with high mortality and morbidity in India as well as globally. The causative agents for this infection are collectively called mucoromycetes which are the members of the order Mucorales. The diagnosis of the infection needs to be performed as soon as the occurrence of clinical symptoms which differs with types of Mucorales infection. Imaging techniques magnetic resonance imaging or computed tomography scan, culture testing, and microscopy are the approaches for the diagnosis. After the diagnosis of the infection is confirmed, rapid action is needed for the treatment in the form of antifungal therapy or surgery depending upon the severity of the infection. Delaying in treatment declines the chances of survival. In antifungal therapy, there are two approaches first-line therapy (monotherapy) and combination therapy. Amphotericin B (1) and isavuconazole (2) are the drugs of choice for first-line therapy in the treatment of mucormycosis. Salvage therapy with posaconazole (3) and deferasirox (4) is another approach for patients who are not responsible for any other therapy. Adjunctive therapy is also used in the treatment of mucormycosis along with first-line therapy, which involves hyperbaric oxygen and cytokine therapy. There are some drugs like VT-1161 (5) and APX001A (6), Colistin, SCH 42427, and PC1244 that are under clinical trials. Despite all these approaches, none can be 100% successful in giving results. Therefore, new medications with favorable or little side effects are required for the treatment of mucormycosis.

Mucormycosis and Its Upsurge During COVID-19 Epidemic: An Updated Review

Although mucormycosis may have reached an epidemic situation during the COVID-19 pandemic, the term was much more familiar even before the COVID-19 period. The year 2020 showed an outbreak of novel coronavirus (SARS-CoV-2) which affected millions of people all over the world. One of the noticeable complications observed to be associated with this disease is mucormycosis. It is an opportunistic infection caused by members of the Order Mucorales existing worldwide and has been commonly reported as a laboratory contaminant for a long time. However, nowadays due to the changes in the host environment, they have been emerging as potent opportunistic pathogens responsible for causing primary infections or coinfections with other diseases eventually resulting in morbidity and even mortality in severe cases. Although immunocompromised patients are more susceptible to this infection, few cases have been reported in immunocompetent individuals. Various risk factors which are responsible for the acquisition of mucormycosis include diabetes mellitus type 2, ketoacidosis, hematological malignancies, organ transplants, and chemotherapy recipients. Among the various etiological agents, Rhizopus is found to be the most common, and rhino-cerebral to be the most frequent clinical presentation. As far as pathogenesis is concerned, host cell invasion, thrombosis, and necrosis are the main events in the progression of this disease. The aim of the present review is to address a complete spectrum of mucormycosis and COVID-19-associated mucormycosis (CAM) in a single article. Both global and Indian scenarios of mucormycosis are taken into account while framing this review.

COVID-19-associated mucormycosis in India: Why such an outbreak?

An unprecedented mucormycosis outbreak occurred in India during the second COVID-19 wave in spring 2021. COVID-19-associated mucormycosis (CAM) was observed, mainly rhino-orbito-cerebral mucormycosis (ROCM), in patients with poorly controlled diabetes and treated with inappropriate doses of glucocorticoids. The aim of this mini-review was to compare the characteristics of the CAM epidemic in India with (i) mucormycosis cases before the COVID-19 pandemic and (ii) CAM in the rest of the world (particularly in France) in order to identify the reasons for this outbreak. In India, the major mucormycosis epidemiologic change during the COVID-19 pandemic was an increase in the percentage of patients treated with corticosteroids who developed CAM. Compared with the rest of the world, India reported a higher mucormycosis incidence even before the COVID-19 pandemic. Moreover, in India, patients with CAM were more likely to have diabetes mellitus and ROCM; conversely, mortality rates were lower. The reasons for such a localized epidemic in India have remained unclear, but some hypotheses can be put forward, particularly the combination of high prevalence of uncontrolled diabetes mellitus and frequent indiscriminate corticosteroid utilization in a country that already had a high mucormycosis burden before the COVID-19 pandemic.

Risk factors for pulmonary mucormycosis in subjects with diabetes mellitus-A case-control study

BACKGROUND

Factors associated with pulmonary mucormycosis (PM) among subjects with diabetes mellitus (DM) remain unclear. Following the coronavirus disease (COVID-19)-associated mucormycosis outbreak in India, specific environmental exposures (especially cattle dung exposure) were proposed as possible aetiology. We hypothesized that environmental factors are associated with PM. We compared subjects with DM with (cases) and without PM (controls).

METHODS

In this case-control study, for each PM case, we included five unmatched diabetic controls (hospital [n = 2], community [n = 3]) without PM. We collected information on demography, COVID-19 infection, glycated haemoglobin% (HbA1c), the type of house (pucca vs. kutcha) where the participants reside, and other environmental factors. The primary exposure tested was cattle dung exposure (CDE; using cattle dung cakes as fuel or cattle handling). We performed a multivariate logistic regression to explore factors associated with PM and report the association as an adjusted odds ratio (OR) with 95% confidence intervals (CI).

RESULTS

We enrolled 39 PM cases and 199 controls (hospital [n = 80], community [n = 119]). CDE (OR 0.68, 95% CI [0.14-3.31]; p = 0.63) was not associated with increased PM in DM. We found male sex (OR 4.07, 95% CI [1.16-14.31]), higher HbA1c (OR 1.51, 95% CI [1.18-16.32]), COVID-19 (OR 28.25, 95% CI [7.02-113.6]) and residence at kutcha house (OR 4.84, 95% CI [1.33-17.52]) associated with PM.

CONCLUSION

Cattle dung exposure was not associated with PM in subjects with DM. Instead, male sex, poor glycaemic control, COVID-19 and the type of housing were associated with pulmonary mucormycosis.

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.

Evaluation of risk factors, clinico-radiographic presentations of COVID-associated mucormycosis in the maxillofacial region reporting to a tertiary care dental facility

Purpose

To evaluate the prevalence of risk factors associated with COVID-associated mucormycosis (CAM) in the maxillofacial region with emphasis on clinical and radiological characteristics of the disease reporting to the dentists.

Methods

Archival records of the patients diagnosed with rhino-cerebral mucormycosis through histopathology or culture, were screened and 266 records were included. These records were divided into three groups-previously diabetic (PD, n = 122), recently diagnosed diabetic (RD, n = 105) and non-diabetic (ND, n = 39). All the records were evaluated and compared among the three groups for the duration of presentation, history of co-existing medical conditions, the association of treatment given during COVID-19, and the clinical and radiographic presentations of the disease.

Results

The results confirmed uncontrolled diabetes mellitus as the major risk factor for the disease. The prevalence of steroid administration was lower in our study in contrast to previous literature. The risk factors and treatment rendered during COVID-19 did not differ significantly among the three groups (p > 0.05). The findings indicate that the disease was milder and progressed more slowly in the ND group, both clinically and radiographically, and it had close resemblance to odontogenic infection.

Conclusion

Patients with early CAM mimicked the odontogenic infection and were more likely to report in a dental setup. Hence, a multidisciplinary and holistic management approach is necessary.

Mucormycosis, past and present: a comprehensive review

Mucormycosis is an emerging opportunistic angioinvasive fungal infection. Predisposing factors such as diabetes, neutropenia, long-term corticosteroid therapy, solid organ transplantation and immunosuppression contribute to its occurrence. This disease was not of significant concern prior to the COVID-19 pandemic, but gained prominence due to infections in COVID-19 patients. Mucormycosis needs special attention and coordinated efforts of the scientific community and medical professionals to reduce morbidity and mortality. Here we present an overview of the epidemiology and prevalence of mucormycosis in the pre- and post-COVID-19 eras, the factors that contributed to the abrupt increase in COVID-19-associated mucormycosis (CAM), the actions taken by the regulatory agencies (including Code Mucor and CAM registry), the existing diagnostic tools and CAM management strategies.

Incidence of COVID-19-Associated Mucormycosis in COVID-19 Patients after Discharge from the COVID-19 Hospital

Background

There are studies available on the prevalence of coronavirus disease 2019 (COVID-19)-associated mucormycosis (CAM) in hospitalized patients but not on the incidence of CAM in post-discharge patients. The aim of our study was to find the incidence of CAM in the patients discharged from a COVID hospital.

Material and Methods

Adult patients with COVID discharged between March 1, 2021 and June 30, 2021 were contacted and enquired about sign and symptoms of CAM. Data of all included patients were collected from electronic records.

Results

A total of 850 patients responded, among which 59.4% were males, 66.4% patients had co-morbidities, and 24.2% had diabetes mellitus. Around 73% of patients had moderate to severe disease and were given steroids; however, only two patients developed CAM post discharge.

Conclusion

The incidence of CAM post discharge was low in our study, which could be attributed to protocolized therapy and intensive monitoring.

Multicenter Case-Control Study of COVID-19-Associated Mucormycosis Outbreak, India

We found inappropriate glucocorticoid therapy and zinc supplementation were significantly associated with these illnesses.

We performed a case–control study across 25 hospitals in India for the period of January–June 2021 to evaluate the reasons for an COVID-19–associated mucormycosis (CAM) outbreak. We investigated whether COVID-19 treatment practices (glucocorticoids, zinc, tocilizumab, and others) were associated with CAM. We included 1,733 cases of CAM and 3,911 age-matched COVID-19 controls. We found cumulative glucocorticoid dose (odds ratio [OR] 1.006, 95% CI 1.004–1.007) and zinc supplementation (OR 2.76, 95% CI 2.24–3.40), along with elevated C-reactive protein (OR 1.004, 95% CI 1.002–1.006), host factors (renal transplantation [OR 7.58, 95% CI 3.31–17.40], diabetes mellitus [OR 6.72, 95% CI 5.45–8.28], diabetic ketoacidosis during COVID-19 [OR 4.41, 95% CI 2.03–9.60]), and rural residence (OR 2.88, 95% CI 2.12–3.79), significantly associated with CAM. Mortality rate at 12 weeks was 32.2% (473/1,471). We emphasize the judicious use of COVID-19 therapies and optimal glycemic control to prevent CAM.

Factors Associated with Mortality in Coronavirus-Associated Mucormycosis: Results from Mycotic Infections in COVID-19 (MUNCO) Online Registry

BACKGROUND

COVID-19-associated mucormycosis (CAM) is associated with high morbidity and mortality. MUNCO is an international database used to collect clinical data on cases of CAM in real time. Preliminary data from the Mycotic Infections in COVID-19 (MUNCO) online registry yielded 728 cases from May to September 2021 in four South Asian countries and the United States. A majority of the cases (694; 97.6%) consisted of a mucormycosis infection. The dataset allowed for the analysis of the risk factors for adverse outcomes from CAM and this analysis is presented in this paper.

METHODS

The submission of cases was aided by a direct solicitation and social media online. The primary endpoints were full recovery or death measured on day 42 of the diagnosis. All patients had histopathologically confirmed CAM. The groups were compared to determine the contribution of each patient characteristic to the outcome. Multivariable logistic regression models were used to model the probability of death after a CAM diagnosis.

RESULTS

The registry captured 694 cases of CAM. Within this, 341 could be analyzed as the study excluded patients with an unknown CAM recovery status due to either an interruption or a lack of follow up. The 341 viable cases consisted of 258 patients who survived after the completion of treatment and 83 patients who died during the period of observation. In a multivariable logistic regression model, the factors associated with an increased risk of mortality include old age (OR = 1.04, 95% CI 1.02-1.07, p = 0.001), history of diabetes mellitus (OR 3.5, 95% CI 1.01-11.9, p = 0.02) and a lower BMI (OR 0.9, 95% CI 0.82-0.98, p = 0.03). Mucor localized to sinus disease was associated with 77% reduced odds of death (OR = 0.23, 95% CI 0.09-0.57, p = 0.001), while cerebral mucor was associated with an increased odds of death (OR = 10.96, 95% CI 4.93-24.36, p = ≤0.0001).

CONCLUSION

In patients with CAM, older age, a history of diabetes and a lower body mass index is associated with increased mortality. Disease limited to the sinuses without a cerebral extension is associated with a lower risk of mortality. Interestingly, the use of zinc and azithromycin were not associated with increased mortality in our study.

Definition, diagnosis, and management of COVID-19-associated pulmonary mucormycosis: Delphi consensus statement from the Fungal Infection Study Forum and Academy of Pulmonary Sciences, India

COVID-19-associated pulmonary mucormycosis (CAPM) remains an underdiagnosed entity. Using a modified Delphi method, we have formulated a consensus statement for the diagnosis and management of CAPM. We selected 26 experts from various disciplines who are involved in managing CAPM. Three rounds of the Delphi process were held to reach consensus (≥70% agreement or disagreement) or dissensus. A consensus was achieved for 84 of the 89 statements. Pulmonary mucormycosis occurring within 3 months of COVID-19 diagnosis was labelled CAPM and classified further as proven, probable, and possible. We recommend flexible bronchoscopy to enable early diagnosis. The experts proposed definitions to categorise dual infections with aspergillosis and mucormycosis in patients with COVID-19. We recommend liposomal amphotericin B (5 mg/kg per day) and early surgery as central to the management of mucormycosis in patients with COVID-19. We recommend response assessment at 4-6 weeks using clinical and imaging parameters. Posaconazole or isavuconazole was recommended as maintenance therapy following initial response, but no consensus was reached for the duration of treatment. In patients with stable or progressive disease, the experts recommended salvage therapy with posaconazole or isavuconazole. CAPM is a rare but under-reported complication of COVID-19. Although we have proposed recommendations for defining, diagnosing, and managing CAPM, more extensive research is required.

Isolated tracheobronchial mucormycosis: report of a case and systematic review of literature

BACKGROUND

Isolated tracheobronchial mucormycosis (ITBM) is an uncommonly reported entity. Herein, we report a case of ITBM following coronavirus disease 2019 (COVID-19) and perform a systematic review of the literature.

CASE DESCRIPTION AND SYSTEMATIC REVIEW

A 45-year-old gentleman with poorly controlled diabetes mellitus presented with cough, streaky hemoptysis, and hoarseness of voice two weeks after mild COVID-19 illness. Computed tomography and flexible bronchoscopy suggested the presence of a tracheal mass, which was spontaneously expectorated. Histopathological examination of the mass confirmed invasive ITBM. The patient had complete clinical and radiological resolution with glycemic control, posaconazole, and inhaled amphotericin B (eight weeks). Our systematic review of the literature identified 25 additional cases of isolated airway invasive mucormycosis. The median age of the 26 subjects (58.3% men) was 46 years. Diabetes mellitus (79.2%) was the most common risk factor. Uncommon conditions such as anastomosis site mucormycosis (in 2 lung transplant recipients), post-viral illness (post-COVID-19 [n=3], and influenza [n=1]), and post-intubation mucormycosis (n=1) were noted in a few. Three patients died before treatment initiation. Systemic antifungals were used in most patients (commonly amphotericin B). Inhalation (5/26; 19.2%) or bronchoscopic instillation (1/26; 3.8%) of amphotericin B and surgery (6/26; 23.1%) were performed in some patients. The case-fatality rate was 50%, primarily attributed to massive hemoptysis.

CONCLUSION

Isolated tracheobronchial mucormycosis is a rare disease. Bronchoscopy helps in early diagnosis. Management with antifungals and control of risk factors is required since surgery may not be feasible.

Mortality-Related Risk Factors for Coronavirus Disease (COVID-19)-Associated Mucormycosis: a systematic review and meta-analysis

Purpose of Review

Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2) can increase the susceptibility of individuals to contracting mucormycosis through several mechanisms. Nowadays, coronavirus disease (COVID-19)-associated mucormycosis (CAM) is a serious public health concern, particularly in developing countries. This meta-analysis aims to identify the risk factors that affect the mortality rate of patients with CAM.

Recent Findings

We systematically searched PubMed, Google Scholar, Scopus, Cochrane library, and preprint databases using pertinent keywords and the reference lists of the included relevant articles from inception till October 27, 2021. In order to reduce the effects of small-scale studies, we only selected cross-sectional, case–control, and cohort studies and case series with at least four patients. We identified 26 articles that included 821 patients with CAM. The effect size (ES) of mortality rate was 28% (95% confidence interval (CI) 20%–38%; I² =82.28%; p for Cochran Q<0.001). The CAM patients with a history of comorbidities other than diabetes (malignancies, transplant, or renal failure), mechanical ventilation due to COVID-19, pulmonary and cerebral mucormycosis, and those who only received medical treatment for mucormycosis had the highest mortality rate.

Summary

Coronavirus disease (COVID-19)-associated mucormycosis (CAM) is a major public health problem, particularly in developing countries. Severe COVID-19 infection, history of mechanical ventilation, early CAM, comorbidities other than diabetes (malignancies, transplant, or renal failure), pulmonary and rhino-orbito-cerebral mucormycosis, and delivering only medical treatment for mucormycosis were the worst prognostic factors in CAM patients. Identifying the mortality-related risk factors in CAM patients may help reduce the mortality rate by implementing optimized treatment approaches.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12281-022-00440-2.

PK, Pillai VM, Nair PP, Dhodapkar R, Ch Toi P, Singh R, Kasthuri N, Kumar GCP, Jaisankar S, Saini V, Kankaria A, Raj A, Goyal A, Sharma V, Khichar S, Soni K, Garg MK, Selvaraj K, B. H. S, Bhavana K, Bharti B, Singh CM, Chaudhary N, R. V, K. G, Palaninathan K, Dube S, Saxena RS, Gupta N, Rathinavel A, Priya S, Arulsundareshkumar, Bellad SA, Kavi A, Harugop AS, Pujary K, Ballala K, Mallya SD, Prasad HM, Ravi D, Balaji NK, Hegde R, Mishra N, Ray S, Karthikeyan S, Ramalingam S, Murali A, Vaidya S, Samadhiya M, Bhojani D, Lakshmanan S, Singh SRB, Pillai N, Deepthi P, Banumathi K, Sumathi V, Ramesh D, Nissar SP, Sheikh KM, Patel MN, Shristava V, Kumar SS, Shantaraman K, Pandian RD, Murhekar M, Aggarwal R. Hyperglycemia and steroid use increase the risk of rhino-orbito-cerebral mucormycosis regardless of COVID-19 hospitalization: Case-control study, India

BACKGROUND

In the ongoing COVID-19 pandemic, an increased incidence of ROCM was noted in India among those infected with COVID. We determined risk factors for rhino-orbito-cerebral mucormycosis (ROCM) post Coronavirus disease 2019 (COVID-19) among those never and ever hospitalized for COVID-19 separately through a multicentric, hospital-based, unmatched case-control study across India.

METHODS

We defined cases and controls as those with and without post-COVID ROCM, respectively. We compared their socio-demographics, co-morbidities, steroid use, glycaemic status, and practices. We calculated crude and adjusted odds ratio (AOR) with 95% confidence intervals (CI) through logistic regression. The covariates with a p-value for crude OR of less than 0·20 were considered for the regression model.

RESULTS

Among hospitalised, we recruited 267 cases and 256 controls and 116 cases and 231 controls among never hospitalised. Risk factors (AOR; 95% CI) for post-COVID ROCM among the hospitalised were age 45-59 years (2·1; 1·4 to 3·1), having diabetes mellitus (4·9; 3·4 to 7·1), elevated plasma glucose (6·4; 2·4 to 17·2), steroid use (3·2; 2 to 5·2) and frequent nasal washing (4·8; 1·4 to 17). Among those never hospitalised, age ≥ 60 years (6·6; 3·3 to 13·3), having diabetes mellitus (6·7; 3·8 to 11·6), elevated plasma glucose (13·7; 2·2 to 84), steroid use (9·8; 5·8 to 16·6), and cloth facemask use (2·6; 1·5 to 4·5) were associated with increased risk of post-COVID ROCM.

CONCLUSIONS

Hyperglycemia, irrespective of having diabetes mellitus and steroid use, was associated with an increased risk of ROCM independent of COVID-19 hospitalisation. Rational steroid usage and glucose monitoring may reduce the risk of post-COVID.

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.

Dietary diversity as a sustainable approach towards micronutrient deficiencies in India

The silent epidemic of micronutrient deficiencies (MNDs) continues to be a major public health challenge in the developing world, including India. The prevalence of iron, iodine, zinc, vitamin A and folate deficiencies is alarmingly high worldwide. India is additionally facing a high prevalence of vitamin D and B12 deficiencies. To combat the hidden epidemic of MNDs, various governments around the world have mostly relied on supplementation or fortification-based interventions. India launched salt iodization programme in 1962 and vitamin A and iron-folate supplementation programmes in 1970. Yet, even after decades of these programmes, MNDs are still widespread in the country. Due to slow progress in alleviating the burden of most MNDs, the Government of India aims to scale up fortification-based intervention programmes. However, there are safety and effectiveness concerns with such approaches. Hence, overdependence on supplementation and fortification alone may be counterproductive. Instead, food based dietary diversification approach can be the way forward. In this article, we list the common MNDs in India, evaluate major policy interventions, discuss concerns pertaining to fortification and suggest the need for a concurrent food-based approach, in particular dietary diversification, as a long-term and sustainable strategy to address population-based MNDs.

Current Treatment Options for COVID-19 Associated Mucormycosis: Present Status and Future Perspectives

Mucormycosis has become increasingly associated with COVID-19, leading to the use of the term “COVID-19 associated mucormycosis (CAM)”. Treatment of CAM is challenging due to factors such as resistance to many antifungals and underlying co-morbidities. India is particularly at risk for this disease due to the large number of patients with COVID-19 carrying comorbidities that predispose them to the development of mucormycosis. Additionally, mucormycosis treatment is complicated due to the atypical symptoms and delayed presentation after the resolution of COVID-19. Since this disease is associated with increased morbidity and mortality, early identification and diagnosis are desirable to initiate a suitable combination of therapies and control the disease. At present, the first-line treatment involves Amphotericin B and surgical debridement. To overcome limitations associated with surgery (invasive, multiple procedures required) and amphotericin B (toxicity, extended duration and limited clinical success), additional therapies can be utilized as adjuncts or alternatives to reduce treatment duration and improve prognosis. This review discusses the challenges associated with treating CAM and the critical aspects for controlling this invasive fungal infection—early diagnosis and initiation of therapy, reversal of risk factors, and adoption of a multipronged treatment strategy. It also details the various therapeutic options (in vitro, in vivo and human case reports) that have been used for the treatment of CAM.

Serum glucose-regulated protein 78 (GRP78) levels in COVID-19-associated mucormycosis: results of a case-control study

BACKGROUND

In experimental models, the expression of glucose-regulated protein 78 (GRP78) in endothelial cells played a role in the pathogenesis of mucormycosis. However, the role of GRP78 in COVID-19-associated mucormycosis (CAM) has not been studied. We hypothesized that serum GRP78 levels are elevated in subjects with CAM.

OBJECTIVE

To compare the serum GRP78 levels in subjects with CAM and COVID-19 controls without mucormycosis.

DESIGN AND SETTING

We performed a hospital-based, case-control study between 1 April 2021 and 31 May 2021.

PARTICIPANTS

We enrolled 24 subjects each of CAM and COVID-19 subjects without mucormycosis. We also measured serum GRP78 levels in ten healthy controls.

EXPOSURE

The primary exposure studied was serum GRP78 concentration, estimated using a commercially available ELISA kit in stored serum samples.

RESULTS

We found the mean ± standard deviation (SD) serum GRP78 levels significantly higher (p = 0.0001) among the CAM (374.3 ± 127.3 pg/mL) than the COVID-19 (246.4 ± 67.0 pg/mL) controls. The proportion of subjects with an abnormal GRP78 level (> mean [184.8 pg/mL] plus two SD [23.2 pg/mL] of GRP78 from healthy participants) was 87.5% and 45.8% in the CAM group and COVID-19 controls, respectively. Serum GRP78 level was independently associated with CAM (odds ratio 1.011; 95% confidence interval [1.002-1.019]) after adjusting for diabetes mellitus and hypoxemia during acute COVID-19.

CONCLUSION

Serum GRP78 levels were significantly higher in CAM than in COVID-19 controls. Further studies are required to the role of GRP78 in the pathogenesis of CAM.

Could cattle dung burning have contributed to the epidemic of COVID-19-associated mucormycosis in India? Results of an experimental aero-mycological study

Background

Several hypotheses have been proposed for explaining the outbreak of coronavirus disease 2019 (COVID‐19)‐associated mucormycosis in India, including the burning of cattle dung cakes, though no study has yet been conducted to support this claim.

Methods

We conducted an aero‐mycological study to evaluate whether Mucorales in the air increased during or after burning cattle dung cakes. We further compared the growth of Mucorales in the indoor air samples from houses with and without cattle. We also cultured fresh and dried cattle dung and soil samples for Mucorales.

Results

We noted no significant difference in the proportion of air samples growing Mucorales during (4/22 [18.2%]) and after (3/2 [13.6%]) cattle dung burning than that collected immediately before (4/22 [18.2%]). Mucorales were isolated in 15.4% of the indoor air samples obtained from different houses (both rural and urban); the proportion of samples growing Mucorales was not significantly different in households with and without cattle. We also observed growth of Mucorales in 6 of the 8 [75%] fresh and 3 of the 6 [50%] dried dung samples. The most common Mucorales isolated from soil and dung samples was Lichtheimia corymbifera, while Rhizopus arrhizus was the most common species isolated from indoor air samples.

Conclusions

We found no significant increase in the proportion of air samples growing Mucorales during or after burning cattle dung cake than that before. It seems unlikely that cattle dung burning contributes to the occurrence of mucormycosis.

Mucormycosis in the COVID-19 Era – A Natural Calamity or Man-Made Disaster? Current Evidence and Review of the Literature

Mucormycosis is a potentially fatal disease caused by a fungus of the order Mucorales, most commonly involving the nasal sinuses, orbits, brain, lungs, and skin. The disease affects mostly immunosuppressed individuals and patients with chronic diseases such as diabetes. The prevalence of mucormycosis is 80 times higher (0.14 per 1000) in India compared to developed countries. Since the outbreak of the COVID-19 pandemic, there has been a sudden surge in the number of mucormycosis cases, especially on the Indian subcontinent. This can be attributed to what we consider to be the perfect iatrogenic recipe: a combination between the immunosuppression caused by COVID-19, the large prevalence of uncontrolled diabetes and the simultaneous use of corticosteroids. Other factors include the excessive use of antibiotics, antifungal drugs and zinc supplements, invasive ventilation, poor hygiene and sanitization as well as the use of industrial oxygen in hospitals. As a result, an overwhelmingly large number of COVID-19 patients have developed mucormycosis during the pandemic. A review of the literature suggests that all efforts should be made to keep tight control of glycemia in COVID-19 patients along with judicious use of corticosteroids. The treatment of mucormycosis involves a combination of medical and surgical therapy, with the early initiation of antifungal drugs and aggressive surgical debridement of the affected tissues.

Clinical Features and Mortality of COVID-19-Associated Mucormycosis: A Systematic Review and Meta-Analysis

The recent increase of COVID-19-associated mucormycosis (CAM) has been commanding global attention. However, basic epidemiologic characteristics have not firmly been established. In this systematic review and meta-analysis, we sought to determine the clinical manifestations, potential risk factors, and outcomes of CAM. Observational studies reporting CAM were searched with PubMed and EMBASE databases in January 2022. We collected data on comorbidities and treatment for COVID-19, and performed a one-group meta-analysis on the frequency of orbital exenteration procedure and mortality of CAM using a random-effect model. Fifty-one observational studies, including a total of 2,312 patients with proven CAM, were identified. Among the 51 studies, 37 were conducted in India, 8 in Egypt, and 6 in other countries. The most common comorbidity was diabetes mellitus (82%). While 57% required oxygenation, 77% received systemic corticosteroids. Among CAM, 97% were rhino-orbital-cerebral (ROCM), and 2.7% were pulmonary mucormycosis. Usual presentations were headache (54%), periorbital swelling/pain (53%), facial swelling/pain (43%), ophthalmoplegia (42%), proptosis (41%), and nasal discharge/congestion (36%). Regarding the outcomes, orbital exenteration was performed in 17% (95% CI: 12–21%, I² = 83%) of the COVID-19-associated ROCM patients. The mortality of CAM was 29% (95% CI; 22–36%, I² = 92%). In conclusion, this systematic review and meta-analysis indicated that the most prevalent type of CAM was ROCM, and most CAM patients had diabetes mellitus and received systemic glucocorticoids. Clinicians in the endemic areas should have a high index of suspicion for this invasive fungal complication of COVID-19 when a diabetic patient who received high-dose systemic glucocorticoids developed rhino-orbital symptoms.

Evaluation of hospital environment for presence of Mucorales during COVID-19 associated mucormycosis outbreak in India – A multi-centre study

Background

An unprecedented rise in the number of COVID-19-associated mucormycosis (CAM) cases has been reported in India. Myriad hypotheses are proposed for the outbreak. We recently reported uncontrolled diabetes and inappropriate steroid therapy as significant risk factors for the outbreak. However, Mucorales contamination of hospital environment was not studied.

Aim

To perform a multi-centre study across India to determine possible Mucorales contamination of hospital environment during the outbreak.

Methods

Eleven hospitals from four zones of India representing high to low incidence for mucormycosis cases were included in the study. Samples from a variety of equipment used by the patients and ambient air were collected during May 19^th, 2021 through August 25^th, 2021.

Findings

None of the hospital equipment sampled was contaminated with Mucorales. However, Mucorales were isolated from 11.1% air-conditioning vents and 1.7% of patients' used masks. Other fungi were isolated from 18% of hospital equipment and surfaces, and 8.1% of used masks. Mucorales grew from 21.7% indoor and 53.8% outdoor air samples. Spore counts of Mucorales in air were significantly higher in the hospitals of North and South zones compared to West and East zones (P < 0.0001). Among Mucorales isolated from the environment, Rhizopus spp. were the most frequent genus.

Conclusion

Contamination of air-conditioning vents and hospital air by Mucorales was found. Presence of Mucorales in these areas demands regular surveillance and improvement of hospital environment, as contamination may contribute to healthcare-associated mucormycosis outbreaks, especially among immunocompromised patients.

Role of Zinc and Clinicopathological Factors for COVID-19-Associated Mucormycosis (CAM) in a Rural Hospital of Central India: A Case-Control Study

Introduction Coronavirus disease 2019 (COVID-19)has been a difficult enemy to beat for healthcare professionals around the world. However, even before the end of the COVID-19 pandemic, there has been an emergence of a new combatant in the form of opportunistic fungal infections with a high rate of morbidity and mortality, creating havoc throughout the globe. Methods A case-control single-center study was conducted in Datta Meghe Institute of Medical Sciences, Wardha, Maharashtra. All the subjects who were included in the study were tested positive for COVID-19 through the reverse transcriptase-polymerase chain reaction (RT-PCR) method and the cases were defined as patients with biopsy-proven mucormycosis, whereas control were subjects who did not develop mucormycosis. The duration of the study was three months, from June 2021 to August 2021. Result A total of 55 cases and 50 controls were enrolled in the study. The use of zinc was found to be significantly associated with COVID-19-associated mucormycosis, with 89.1% of the cases having a history of zinc intake and only 52% of controls having a history of zinc intake( p-value <0.001). Diabetes mellitus was found to be significantly associated with COVID-19-associated mucormycosis with 83.6% of the cases and 16% of the controls having diabetes mellitus (p-value <0.001). Although the use of steroids in cases was more with 98.2% of the cases and 54% of the control receiving steroids; this difference was not significant statistically (p-value of 1.00). Conclusion We conclude that apart from diabetes mellitus and other immunosuppressive states, zinc might be the hidden culprit behind the sudden surge of COVID-19-associated mucormycosis worldwide owing to the self-administration of zinc by the patients to acquire innate immunity and over-prescription of multivitamins by the treating clinicians. However, this association required further studies in order to be proved.

Are Ayurvedic medications store house of heavy metals?

Ayurvedic formulations are widely used and perceived as safer medicine and subjected to be self-prescribed. However, recent reports have demonstrated adulterating these drugs with toxic quantities of heavy metals. To study the magnitude of the problem in Indian-manufactured Ayurvedic medications, we randomly collected common over-the-counter Ayurvedic preparations from the licensed Ayurvedic shops in the local markets of Chandigarh in 2017. The samples were analyzed to identify and quantify eight metal ions, including mercury, arsenic, lead, cadmium, zinc, iron, copper, and chromium, using inductively coupled plasma mass spectrometry in Postgraduate Institute of Medical Education and Research, Chandigarh. The permissible limit set by the Food and Agriculture Organization/World Health Organization (FAO/WHO) for herbal medicines was followed to define the high metal concentrations. Out of 43 Ayurvedic preparations, 42 were analyzed. Heavy metals were detected in all formulations. The median (range) concentrations (in μg/g or mg/kg) of the metals were quantified as follows- mercury, 13.52 (0.00-61 095.99); arsenic, 0.00 (0.00-1038.83); lead, 1.40 (0.00-57.09); zinc, 84.2200 (26.48-22 519.03); iron, 1356.21 (128.24-136 835.25); copper, 17.1450 (0.00-12 756.86) and chromium, 20.9050 (0.00-2717.58). The metal contents above the FAO/WHO-mandated limit for zinc, mercury, arsenic, and lead were detected in 35, 29, 6, and 2 formulations, respectively. All medications contained detectable quantities of zinc and iron. Copper was detected in all except one. Cadmium was not found in any sample. Ayurvedic medications have a high prevalence of heavy metals. An evaluation of the sources of contamination and the necessary drug safety regulations are required.

Pulmonary Artery Pseudoaneurysm in COVID-19-Associated Pulmonary Mucormycosis: Case Series and Systematic Review of the Literature

Literature on COVID-19-associated pulmonary mucormycosis (CAPM) is sparse. Pulmonary artery pseudoaneurysm (PAP) is an uncommon complication of pulmonary mucormycosis (PM), and rarely reported in CAPM. Herein, we report five cases of CAPM with PAP managed at our center and perform a systematic review of the literature. We diagnosed PM in those with clinico-radiological suspicion and confirmed it by microbiology or histopathology. We encountered five cases of CAPM with PAP (size ranged from 1 × 0.8 cm to ~ 4.9 × 4.8 cm). All subjects had diabetes and were aged 55–62 years (75% men). In two cases, COVID-19 and mucormycosis were diagnosed simultaneously, while in three others, COVID-19 preceded PM. One subject who underwent surgery survived, while all others died (80% mortality). From our systematic review, we identified one additional case of CAPM with PAP in a transplant recipient. CAPM with PAP is rare with high mortality. Early diagnosis and multimodality management are imperative to improve outcomes.

Pulmonary mucormycosis in the aftermath of critical COVID-19 in an immunocompromised patient: Mind the diagnostic gap

Mucormycosis has recently been recognized as a severe complication of COVID-19 with high fatality rates. We report a fatal case of COVID-19 associated mucormycosis (CAM) in a non-diabetic immunocompromised patient, who was first misdiagnosed and treated for COVID-19 associated aspergillosis (CAPA). The risk factors and initial clinical presentation of CAPA and CAM are similar, but CAM has a more aggressive course and CAPA and CAM are treated differently. Dedicated diagnostic workup is essential to ensure early treatment of CAM with surgical debridement and targeted antifungal therapy.

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.

Serum iron indices in COVID-19-associated mucormycosis: A case-control study

BACKGROUND

Whether dysregulated iron metabolism is associated with COVID-19-associated mucormycosis (CAM) remains unknown. Herein, we compare the serum iron indices in COVID-19 subjects with and without mucormycosis.

METHODS

We conducted a case-control study enrolling COVID-19 participants with and without mucormycosis. We compared the baseline serum iron indices (iron, ferritin, total iron-binding capacity [TIBC], unsaturated iron-binding capacity and percentage transferrin saturation) between CAM cases and COVID-19 controls. Additionally, we performed a multivariate logistic regression analysis to assess whether any iron indices are associated with CAM.

RESULTS

We enrolled 28 CAM cases (mean age 53.6 years old; 78.6% men) and 26 controls (mean age 57.2 years old; 73.1% men). Rhino-orbital (±cerebral) mucormycosis (85.7%) was the most clinical presentation. Diabetes mellitus was more frequent in the cases than controls (75% vs. 42.3%; p = .015). Hypoxaemia during COVID-19 illness was more common in controls than cases. The mean serum iron values (33 vs. 45 μg/dl, p = .03) and TIBC (166.6 vs. 201.6 μg/dl, p = .003) were significantly lower in CAM cases than controls. On multivariate analysis, we found a lower TIBC (odds ratio [OR] 0.97; 95% confidence interval [CI], 0.95-0.99) and diabetes mellitus (OR 5.23; 95% CI, 1.21-22.68) to be independently associated with CAM after adjusting for serum iron, ferritin and glucocorticoid therapy. The case fatality rate of CAM was 73.9%. The iron indices were not significantly different between CAM survivors and non-survivors.

CONCLUSIONS

The CAM is associated with lower TIBC levels than COVID-19 subjects without mucormycosis, suggesting dysregulated iron metabolism in its pathogenesis. Further studies are required to confirm our preliminary observations.

Results from a national survey on COVID-19-associated mucormycosis in Germany: 13 patients from six tertiary hospitals

BACKGROUND

Most COVID-19-associated mucormycosis (CAM) cases are reported from India and neighbouring countries. Anecdotally cases from Europe have been presented.

OBJECTIVE

To estimate the disease burden and describe the clinical presentation of CAM in Germany.

METHODS

We identified cases through German mycology networks and scientific societies, and collected anonymised clinical information via FungiScope®.

RESULTS

We identified 13 CAM cases from six tertiary referral hospitals diagnosed between March 2020 and June 2021. Twelve patients had severe or critical COVID-19, eleven were mechanically ventilated for a median of 8 days (range 1-27 days) before diagnosis of CAM. Eleven patients received systemic corticosteroids. Additional underlying medical conditions were reported for all but one patient, five were immunocompromised because of malignancy or organ transplantation, three were diabetic. Eleven patients developed pneumonia. Mortality was 53.8% with a median time from diagnosis of mucormycosis to death of 9 days (range 0-214 days) despite treatment with liposomal amphotericin B and/or isavuconazole in 10 of 13 cases. CAM prevalence amongst hospitalised COVID-19 patients overall (0.67% and 0.58% in two centres) and those admitted to the intensive care unit (ICU) (1.47%, 1.78% and 0.15% in three centres) was significantly higher compared to non-COVID-19 patients (P < .001 for respective comparisons).

CONCLUSION

COVID-19-associated mucormycosis is rare in Germany, mostly reported in patients with comorbidities and impaired immune system and severe COVID-19 treated in the ICU with high mortality compared to mainly rhino-orbito-cerebral CAM in patients with mild COVID-19 in India. Risk for CAM is higher in hospitalised COVID-19 patients than in other patients.