COVID-19-Associated Candidiasis: Possible Patho-Mechanism, Predisposing Factors, and Prevention Strategies

Abstract

The coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is threatening public health. A large number of affected people need to be hospitalized. Immunocompromised patients and ICU-admitted patients are predisposed to further bacterial and fungal infections, making patient outcomes more critical. Among them, COVID-19-associated candidiasis is becoming more widely recognized as a part of severe COVID-19 sequelae. While the molecular pathophysiology is not fully understood, some factors, including a compromised immune system, iron and zinc deficiencies, and nosocomial and iatrogenic transmissions, predispose COVID-19 patients to candidiasis. In this review, we discuss the existing knowledge of the virulence characteristics of Candida spp. and summarize the key concepts in the possible molecular pathogenesis. We analyze the predisposing factors that make COVID-19 patients more susceptible to candidiasis and the preventive measures which will provide valuable insights to guide the effective prevention of candidiasis in COVID-19 patients.

COVID-19-associated fungal infections in Iran: A systematic review

“…The SARS-CoV-2 infection can cause lymphopenia and consequent impairment of immune defense against fungal agents including Candida spp. [ 41 , 42 ]. Severe COVID-19 is associated with elevation of blood lactate and acidosis [ 43 , 44 ], which enables Candida to restructure its cell wall to mask β-glucans and escape the recognition by the host immune system [ 45 ].…”

“…Severe COVID-19 is associated with elevation of blood lactate and acidosis [ 43 , 44 ], which enables Candida to restructure its cell wall to mask β-glucans and escape the recognition by the host immune system [ 45 ]. Moreover, an important virulence factor of Candida that helps it evade phagocytosis is the ability to form biofilms, which can be triggered by COVID-19 through increasing oxidative stress and pH imbalance [ 41 ].…”

“…On the other hand, COVID-19 patients are at an increased risk of contracting candidiasis because of the treatments they receive. Consumption of corticosteroids, antibiotics, and TNF-α inhibitors, as well as undergoing mechanical ventilation, central venous catheterization, and extracorporeal membrane oxygenation (ECMO) are risk factors for developing candidiasis [ 41 , 46 – 48 ]. Concordant to previous studies, a significant proportion of the patients in our review were exposed to antibiotic consumption, corticosteroid use, mechanical ventilation, and central venous catheterization.…”

“…Another predictor of developing CAC is admission to ICU, which is often accompanied by interventions such as mechanical ventilation and central venous catheterization and can raise the risk of nosocomial Candida infections [ 41 ]. In our study, 55% of the CAC cases (100% of patients with candidemia) stayed in ICU, emphasizing the need for more attention to ICU patients in terms of prompt diagnosis of candidiasis.…”

Effect of Indoor Bioaerosols (Fungal) Exposure on the Health of Post-COVID-19 Patients and Possible Mitigation Strategies

“…There is more concern regarding Candida auris meningitis cases, because the number of cases with Cauris meningitis has continuously been increasing in the United Kingdom, India, and Iran [43]. Some factors, such as a compromised immune system, deficiency of iron and zinc, and nosocomial and iatrogenic transmissions, result in patients being prone to infection from candidiasis during COVID-19 treatment [44]. One of the significant findings was that all of the patient samples were resistant to amphotericin B [10].…”