Mucormycosis: A deadly black fungus infection among COVID-19 patients in India

Retrospective study of patient characteristics and treatment for mucormycosis in post COVID-19 population in a tertiary care hospital

OBJECTIVES

Along with the COVID-19 pandemic, another illness wreaking havoc in India is mucormycosis, also known as black fungus. Mucormycosis was previously known as zygomycotic infection, which is a consequential type of infection caused by several mildews known as Mucoromycetes. It is an invasive type of disease which occurs more commonly in individuals with low and weakened immunity. The main objective of this study was to identify the mucormycosis cases post COVID-19 and to determine the risk factors and treatment for positive cases.

METHODS

Thirty-three patients (61% men, 39% women; mean age 55 years) with mucormycosis were identified in the Department of Oral and Maxillofacial Surgery.

RESULTS

People who received COVID-19 vaccines had a lower rate of infection with the fungus than non-vaccinated people. In steroid users the risk was very high compared with those not taking steroids.

CONCLUSION

The majority of non vaccinated patients with preexisting co-morbidity conditions like diabetes, chronic illnesses and irregular use of steroids during COVID-19, might have greater risks of getting mucormycosis rather than normal COVID-19 positive cases.

Trans-kingdom fungal pathogens infecting both plants and humans, and the problem of azole fungicide resistance

Azole antifungals are abundantly used in the environment and play an important role in managing fungal diseases in clinics. Due to the widespread use, azole resistance is an emerging global problem for all applications in several fungal species, including trans-kingdom pathogens, capable of infecting plants and humans. Azoles used in agriculture and clinics share the mode of action and facilitating cross-resistance development. The extensive use of azoles in the environment, e.g., for plant protection and wood preservation, contributes to the spread of resistant populations and challenges using these antifungals in medical treatments. The target of azoles is the cytochrome p450 lanosterol 14-α demethylase encoded by the CYP51 (called also as ERG11 in the case of yeasts) gene. Resistance mechanisms involve mainly the mutations in the coding region in the CYP51 gene, resulting in the inadequate binding of azoles to the encoded Cyp51 protein, or mutations in the promoter region causing overexpression of the protein. The World Health Organization (WHO) has issued the first fungal priority pathogens list (FPPL) to raise awareness of the risk of fungal infections and the increasingly rapid spread of antifungal resistance. Here, we review the main issues about the azole antifungal resistance of trans-kingdom pathogenic fungi with the ability to cause serious human infections and included in the WHO FPPL. Methods for the identification of these species and detection of resistance are summarized, highlighting the importance of these issues to apply the proper treatment.

A Systematic Review of the Therapeutic Outcome of Mucormycosis

Background

Mucormycosis is a potentially lethal mycosis. We reviewed peer-reviewed publications on mucormycosis to assess therapeutic outcomes.

Methods

A systematic literature search using the Ovid MEDLINE and EMBASE databases identified manuscripts describing human mucormycosis diagnosed according to European Organization for Research and Treatment of Cancer and the Mycoses Study Group criteria with therapeutic outcomes published from 2000 to 2022.

Results

In 126 articles, 10 335 patients were described, most from Asia (n = 6632, 66%). Diabetes was the most frequent underlying disease (n = 6188, 60%); 222 (2.1%) patients had no underlying diseases. The dominant clinical form was rhino-orbitocerebral (n = 7159, 69.3%), followed by pulmonary (n = 1062, 10.3%). Of 5364 patients with outcome data, amphotericin B monotherapy (n = 3749, mortality 31.5%) was most frequent, followed by amphotericin B + azole (n = 843, mortality 6.6%; P < .0001), amphotericin B followed by azole (n = 357, mortality 13.7%; P < .0001), posaconazole only (n = 250, mortality 17.2%; P < .0001), and isavuconazole only (n = 65, mortality 24.6%; P = .24). Duration and dose of antifungals varied widely. Documented outcomes from surgical resections in 149 patients found that 47 of 125 died (37.6%), compared with 16 of 24 (66.7%) patients who did not undergo surgery (P = .008).

Conclusions

Mucormycosis is more frequently reported in Asia than in Europe and is often linked to diabetes. Antifungal therapy, usually with surgery, is frequently effective for mucormycosis.

Green Chemistry and In silico Techniques for Synthesis of Novel Pyranopyrazole and Pyrazolo-pyrano-pyrimidine Derivatives as Promising Antifungal Agents

BACKGROUND

Every year Invasive Fungal Infections (IFI) are globally affecting millions of people. Candida albicans and Aspergillus niger have been reported as the most infectious and mortality-inducing fungal strains among all pathogenic fungi.

AIMS & OBJECTIVES

To tackle this problem in the current study Pyranopyrazoles and Pyrazolopyrano- pyrimidine derivatives were developed using molecular hybridization, green chemistry and one-pot multicomponent reaction.

MATERIALS AND METHODS

In the present work, New Chemical entities (NCE's) were developed on the basis of Structure activity relationship. All designed NCE's were screened for ADMET studies using the QikProp module of Schrodinger software. NCE's with zero violations were further docked on the crystal structure of 14α demethylase, cytochrome P450 and thymidine synthase (PDB ID: 5V5Z, 7SHI, 1BID). Selected molecules were synthesized using green chemistry techniques and evaluated for in vitro antifungal activity against Candida albicans and Aspergillus niger.

RESULTS AND DISCUSSION

Designed NCE's (B1-12 and C1-11) showed favorable results in ADMET studies. In the docking study six compounds from series-B and five molecules from series- C showed good dock score and binding interaction when compared with the standard drugs. Compounds B-3 and C-4 showed the highest zone of inhibition activity against Candida albicans, where as B-1 and C-3 had shown highest zone of inhibition activity against Aspergillus niger.

CONCLUSION

Bicyclic ring (series B) showed better activity as compare to fused tricyclic ring (series C).

Network pharmacology, molecular docking-driven, Qbd-Engineered antifungal in-situ gel loaded with voriconazole nanostructured lipid carriers

Fungal infections (FIs) affect majority of the population, but the current treatments face challenges in terms of their effectiveness. This study focused on specific fungal targets, including dihydrofolate reductase (DHFR), acetohydroxy-acid synthase (AHAS), farnesyltransferase and endoglucanase. The docking studies were conducted with the drug voriconazole (VCZ), comparing it with Fluconazole (FCZ) and Amphotericin B (ATB) against 11 protein data bank (PDB) IDs (IDYR, 3NZB, 6DEQ, 1KS5, 7T0C, 1FY4, 5AJH, 7R79, 6TZ6 and 6IDY). Molecular dynamics (MD) analysis, including RMSD, RMSF, PCA and FEL, confirmed the stability of VCZ. The solubility of VCZ was a problem, so nanostructured lipid carriers (NLCs) were developed to improve ocular penetration. VCF5 was the optimized formulation by using 32 full factorial design. VCZF5-NLCs were the best in terms of nanoparticle size (126.6 nm), Zeta potential (33.5 mV), drug content (DC; 97.38 ± 0.210), encapsulation efficiency (EE; 88.01 ± 0.272) and extended drug release. The results of the ex-vivo corneal diffusion study indicate that VCZ-NLC-loaded in-situ gel (VCZ-NLC-IG3) exhibited DC of 88.25% and drug entrapment (DE) of 74.2%. The results of the zone of inhibition indicated that VCZ-NLC-IG3 had superior efficacy compared to ATB. Network pharmacology showed VCZ interacts with the genes which are responsible for fungus ergosterol biosynthesis, including lanosterol 14-alpha demethylase inhibitors (ERG11), ergosterol biosynthesis protein 5 (ERG5), dimethylallyltransferase 2 (DIT2), ketosynthase (KCN), methylsterol monooxygenase (MSMO1), lamin B receptor (LBR), squalene epoxidase (SQLE), 3-hydroxy-3-methylglutaryl-coenzyme A Reductase (MGCR), 3-hydroxy-3-methylglutaryl-coenzyme A Synthase (HMGCS) and 3-keto-steroid reductase (HSD17B7). In conclusion, the optimized VCZ-loaded NLCs present a promising approach to treat ocular FIs.Communicated by Ramaswamy H. Sarma.

Coronavirus disease (COVID-19)-associated mucormycosis (CAM): The unholy triad of COVID-19, diabetes mellitus, and corticosteroid therapy

The whole world has battled with multiple waves of coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 virus. However, the second wave of COVID-19 had caused a worldwide havoc in terms of disease transmissibility, severity, and mortality. India has been among the worst hit countries during the second wave, which substantially overburdened and overwhelmed the Indian health care system. While secondary infections and co-infections among COVID-19 patients were increasingly being reported, COVID-19-associated mucormycosis (CAM) emerged as a new challenge particularly from India and became a matter of immediate concern. The most common causes attributed to the rise of CAM were undiagnosed/uncontrolled diabetes mellitus, excessive use of corticosteroids, and prolonged hospital stay, all of which create a perfect environment for mucormycosis infection to set in.

The Study of Clinical Profile of Patients With Mucormycosis During COVID-19 Pandemic in Tertiary Care Hospital

INTRODUCTION

Mucormycosis has gained a huge number of cases in the second wave of post COVID-19 infection, which may be attributed to increased awareness, advancement in diagnostic techniques, and an increase in the prevalence of predisposing factors. This study evaluated the pattern, risk factors, and clinical profile of patients with mucormycosis during the second wave of the COVID-19 pandemic.

METHODS

A prospective observational study was conducted in the Department of Emergency Medicine of a dedicated tertiary care hospital for COVID-19. The Institutional Ethics Committee approved the study. One hundred five patients diagnosed with mucormycosis were included from June 2021 to December 2021. Informed consent was obtained from the patients. Data on demography, clinical features, predisposing factors, co-morbid conditions, and microbiological samples were obtained and analyzed.

RESULTS

 Out of 105 patients, 71 were male, and 34 were female. The patient presented with mucormycosis between the 2nd and 3rd week of post COVID-19 infection. Incidence was mainly seen in patients in their fifties, mostly associated with diabetes mellitus (DM) (53.30%), oxygen administration (80%), and previous use of steroids (45.71%). Predominantly, males were more affected. The most common presentation was headache (50.47%), orbital pain with restricted ocular movement (47.67%), proptosis (42.85%), and diminished vision (41.90%). Rhino-orbital-cerebral mucormycosis (ROCM) was the most common presentation of mucormycosis, while only five cases of pulmonary mucormycosis were found.

CONCLUSION

ROCM was the most common presentation of mucormycosis between the second and third week of post COVID-19 infection. Diabetes mellitus and inadvertent use of steroids were major predisposing factors. Therefore, a high degree of suspicion and early diagnosis with initiation of treatment is warranted in cases of mucormycosis in post COVID-19 infection.

Transcriptome analysis reveals increased abundance and diversity of opportunistic fungal pathogens in nasopharyngeal tract of COVID-19 patients

We previously reported that SARS-CoV-2 infection reduces human nasopharyngeal commensal microbiomes (bacteria, archaea and commensal respiratory viruses) with inclusion of pathobionts. This study aimed to assess the possible changes in the abundance and diversity of resident mycobiome in the nasopharyngeal tract (NT) of humans due to SARS-CoV-2 infections. Twenty-two (n = 22) nasopharyngeal swab samples (including COVID-19 = 8, Recovered = 7, and Healthy = 7) were collected for RNA-sequencing followed by taxonomic profiling of mycobiome. Our analyses indicate that SARS-CoV-2 infection significantly increased (p < 0.05, Wilcoxon test) the population and diversity of fungi in the NT with inclusion of a high proportion of opportunistic pathogens. We detected 863 fungal species including 533, 445, and 188 species in COVID-19, Recovered, and Healthy individuals, respectively that indicate a distinct mycobiome dysbiosis due to the SARS-CoV-2 infection. Remarkably, 37% of the fungal species were exclusively associated with SARS-CoV-2 infection, where S. cerevisiae (88.62%) and Phaffia rhodozyma (10.30%) were two top abundant species. Likewise, Recovered humans NT samples were predominated by Aspergillus penicillioides (36.64%), A. keveii (23.36%), A. oryzae (10.05%) and A. pseudoglaucus (4.42%). Conversely, Nannochloropsis oceanica (47.93%), Saccharomyces pastorianus (34.42%), and S. cerevisiae (2.80%) were the top abundant fungal species in Healthy controls nasal swabs. Importantly, 16% commensal fungal species found in the Healthy controls were not detected in either COVID-19 patients or when they were cured from COVID-19 (Recovered). We also detected several altered metabolic pathways correlated with the dysbiosis of fungal mycobiota in COVID-19 patients. Our results suggest that SARS-CoV-2 infection causes significant dysbiosis of mycobiome and related metabolic functions possibly play a determining role in the progression of SARS-CoV-2 pathogenesis. These findings might be helpful for developing mycobiome-based diagnostics, and also devising appropriate therapeutic regimens including antifungal drugs for prevention and control of concurrent fungal coinfections in COVID-19 patients.

Infections and immunity: associations with obesity and related metabolic disorders

About one-fourth of the global population is either overweight or obese, both of which increase the risk of insulin resistance, cardiovascular diseases, and infections. In obesity, both immune cells and adipocytes produce an excess of pro-inflammatory cytokines that may play a significant role in disease progression. In the recent coronavirus disease 2019 (COVID-19) pandemic, important pathological characteristics such as involvement of the renin-angiotensin-aldosterone system, endothelial injury, and pro-inflammatory cytokine release have been shown to be connected with obesity and associated sequelae such as insulin resistance/type 2 diabetes and hypertension. This pathological connection may explain the severity of COVID-19 in patients with metabolic disorders. Many studies have also reported an association between type 2 diabetes and persistent viral infections. Similarly, diabetes favors the growth of various microorganisms including protozoal pathogens as well as opportunistic bacteria and fungi. Furthermore, diabetes is a risk factor for a number of prion-like diseases. There is also an interesting relationship between helminths and type 2 diabetes; helminthiasis may reduce the pro-inflammatory state, but is also associated with type 2 diabetes or even neoplastic processes. Several studies have also documented altered circulating levels of neutrophils, lymphocytes, and monocytes in obesity, which likely modifies vaccine effectiveness. Timely monitoring of inflammatory markers (e.g., C-reactive protein) and energy homeostasis markers (e.g., leptin) could be helpful in preventing many obesity-related diseases.

[Postcovid sino-orbital mucormycosis: a case report]

We describe a case of postcovid sino-orbital mucormycosis in a 74-year-old patient with diabetes mellitus. Orbital symptoms appeared after discharge from the covid hospital, in the third week of the disease and were represrnted by ptosis, proptosis, ophthalmoplegia, blindness and pain in the right eye, numbness of the right half of the face, edema of the periorbital region and cheek. The diagnosis of mucormycosis was confirmed by fluorescence microscopy of the discharge from the middle nasal meatus. SCT of the paranasal sinuses revealed pansinusitis with predominant destructive changes in the right maxillary, ethmoid and sphenoid sinuses. The patient underwent emergency endoscopic debridment, orbital decompression, orbitotomy; treatment with amphotericin B intravenously was started. 10 days after due to the deterioration of the patient's condition, more aggressive debridment of paranasal sinuses was performed: right maxillary sinus anterior, posterior and medial walls resection, medial orbital wall resection, necrectomy of the nasal cavity, paranasal sinuses, orbit, pterygopalatine fossa. Antifungal treatment was continued in the postoperative period. The patient was discharged on the 22nd day of stay in the ENT hospital.

Machine learning based predictive model and systems-level network of host-microbe interactions in post-COVID-19 mucormycosis

Mucormycosis, a rare infection is caused by fungi Mucorales. The affiliation of mucormycosis with Coronavirus disease (COVID-19) is a rising issue of concern in India. There have been numerous case reports of association of rhino-cerebral-orbital, angioinvasive, pulmonary, respiratory and gastrointestinal tract related mucormycosis in patients with history of COVID-19. The immune dysregulation, preposterous use of steroids, interleukin-6-directed therapies and mechanical ventilation in COVID-19 immunocompromised individuals hypothesizes and predisposes to advancement of mucormycosis. The gaps in mode of presentation, disease course, diagnosis and treatment of post-COVID-19 mucormycosis requires critical analysis in order to control its morbidity and incidence and for prevention and management of opportunistic infections in COVID-19 patients.

Our study performs machine learning, systems biology and bioinformatics analysis of post-COVID-19 mucormycosis in India incorporating multitudinous techniques. Text mining identifies candidate characteristics of post-COVID-19 mucormycosis cases including city, gender, age, symptoms, clinical parameters, microorganisms and treatment. The characteristics are incorporated in a machine learning based disease model resulting in predictive potentiality of characteristics of post-COVID-19 mucormycosis. The characteristics are used to create a host-microbe interaction disease network comprising of interactions between microorganism, host-microbe proteins, non-specific markers, symptoms and drugs resulting in candidate molecules. R1A (Replicase polyprotein 1a) and RPS6 (Ribosomal Protein S6) are yielded as potential drug target and biomarker respectively via potentiality analysis and expression in patients. The potential risk factors, drug target and biomarker can serve as prognostic, early diagnostic and therapeutic molecules in post-COVID-19 mucormycosis requiring further experimental validation and analysis on post-COVID-19 mucormycosis cases.