A Simple and Rapid Fungal DNA Isolation Assay Based on ZnO Nanoparticles for the Diagnosis of Invasive Aspergillosis

Nanomedicine as a promising strategy for the theranostics of infectious diseases

Infectious diseases caused by bacteria, viruses, and fungi and their global spread pose a great threat to human health. The 2019 World Health Organization report predicted that infection-related mortality will be similar to cancer mortality by 2050. Particularly, the global cumulative numbers of the recent outbreak of coronavirus disease (COVID-19) have reached 110.7 million cases and over 2.4 million deaths as of February 23, 2021. Moreover, the crisis of these infectious diseases exposes the many problems of traditional diagnosis, treatment, and prevention, such as time-consuming and unselective detection methods, the emergence of drug-resistant bacteria, serious side effects, and poor drug delivery. There is an urgent need for rapid and sensitive diagnosis as well as high efficacy and low toxicity treatments. The emergence of nanomedicine has provided a promising strategy to greatly enhance detection methods and drug treatment efficacy. Owing to their unique optical, magnetic, and electrical properties, nanoparticles (NPs) have great potential for the fast and selective detection of bacteria, viruses, and fungi. NPs exhibit remarkable antibacterial activity by releasing reactive oxygen species and metal ions, exerting photothermal effects, and causing destruction of the cell membrane. Nano-based delivery systems can further improve drug permeability, reduce the side effects of drugs, and prolong systemic circulation time and drug half-life. Moreover, effective drugs against COVID-19 are still lacking. Recently, nanomedicine has shown great potential to accelerate the development of safe and novel anti-COVID-19 drugs. This article reviews the fundamental mechanisms and the latest developments in the treatment and diagnosis of bacteria, viruses, and fungi and discusses the challenges and perspectives in the application of nanomedicine.

Diagnostic performance of real-time polymerase chain reaction assay on blood for invasive aspergillosis and mucormycosis

OBJECTIVES

This study aimed to evaluate the diagnostic usefulness of real-time (RT) polymerase chain reaction (PCR) on blood samples for diagnosis of invasive aspergillosis and mucormycosis in patients with suspected invasive mould infection.

METHODS

Adult patients with suspected invasive mould infection were prospectively enrolled at a tertiary referral hospital in Seoul, South Korea between 2017 and 2020. Standard tests for diagnosis of invasive mould infection and RT-PCR for Aspergillus, Mucor and Rhizopus using blood samples were performed. We evaluated the diagnostic performance of RT-PCR tests in patients diagnosed with proven and probable invasive aspergillosis or mucormycosis infection, according to the modified definitions of the EORTC/MSG 2019.

RESULTS

A total of 102 patients with suspected invasive mould infection were enrolled. Of these patients, 46 (45%) were classified as having proven (n = 13) or probable (n = 33) invasive aspergillosis, 21 (21%) as proven (n = 17) or probable (n = 4) invasive mucormycosis and 18 (18%) as possible invasive mould infection. The remaining 13 (13%) were classified as not having invasive mould infection. Patients with possible invasive mould infection (n = 18) and coinfection of aspergillosis and mucormycosis (n = 4) were excluded from the final analysis. The sensitivity and specificity of the Aspergillus PCR were 54.3% ([25/46], 95% confidence interval [CI]: 40.2-67.9%) and 94.1% ([32/34], 95% CI: 80.9-98.4%), respectively. The sensitivity and specificity of the Mucor or Rhizopus PCR were 57.1% ([12/21], 95% CI: 36.6-75.5%) and 76.3% ([45/59], 95% CI: 64.0-85.3), respectively.

CONCLUSIONS

Our study suggests that blood PCR can be a useful adjunct test for diagnosing patients with suspected invasive mould infection.