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Virulence Factors Detection in Aspergillus Isolates from Clinical and Environmental Samples
Raksha1, Gurjeet Singh1, A D Urhekar2
1Assistant Professor, Department of Microbiology, N. C. Medical College and Hospital, Panipat, Haryana, India.
Introduction:
Pathogenesis of aspergillosis is dependent on various factors of the host (immune status) and virulence factors of the pathogen which could play a significant role in the pathogenesis of invasive aspergillosis.
Aim:
To study the virulence factors of Aspergillus species isolated from patient samples and environmental samples.
Materials And Methods:
This prospective and experimental study was carried out at Department of Microbiology, MGM Medical College and Hospital, Mumbai, Maharashtra, India, from July 2014 to June 2015. For detection of virulence factors of Aspergillus species, total 750 samples were included in this study (350 from patients and 400 samples from environment). Patient samples and hospital environment samples were subjected to standard methods for screening of Biofilm, Lipase, α-amylase, proteinase, haemolysin, phospholipase and pectinase. Statistical analysis was done using Chi-square test and SPSS (Version 17.0).
Results:
American Type Culture Collection (ATCC) control of Aspergillus oryzae, Aspergillus niger and Aspergillus brasiliensis showed production of all virulence factors. In patient samples maximum virulence factor was produced i.e., α-amylase activity (89.74%) followed by proteinase activity (87.17%), biofilm production was (82.05%) haemolysin activity (79.48%), lipase activity (66.66%), pectinase activity and phospholipase activity (61.53%). In environment samples maximum virulence factor was produced i.e., proteinase activity (41.02%) followed by biofilm production was (38.46%), α-amylase activity (35.89%), haemolysin activity (33.33%), lipase activity (28.20%), phospholipase (25.64%) and pectinase activity (23.07%). The differences in patient and environment virulence factors were statistically significant (p-value <0.05).
Conclusion:
Overall the presence of virulence factors was found more in Aspergillus species isolated from patient samples then environmental samples. This could be due to invasiveness nature of Aspergilli. Aspergillusniger was common isolates from both patient and environmental samples. Our study highlights the possible transmission of Aspergilli from environment to patient. Detection of virulence factors of Aspergillus species help to differentiate between pathogenic and non-pathogenic Aspergilli. Presence of virulence factors confirmed pathogenicity of the isolates. It also helps the physicians to treat the patient when appropriate treatment is needed.
Insights
Virulence factors like biofilm and enzymes were more prevalent in Aspergillus species from patients than the environment. This suggests environmental transmission and aids in identifying pathogenic strains for better patient treatment.
Area of Science:
- Medical Microbiology
- Mycology
- Infectious Diseases
Background:
- Aspergillosis pathogenesis is influenced by host immune status and pathogen virulence factors.
- Understanding virulence factors is crucial for managing invasive aspergillosis.
- Aspergillus species are opportunistic fungal pathogens with diverse virulence mechanisms.
Purpose of the Study:
- To investigate and compare the prevalence of key virulence factors in Aspergillus species.
- To analyze isolates from both clinical patient samples and the hospital environment.
- To assess the role of specific enzymes and biofilm formation in Aspergillus pathogenicity.
Main Methods:
- A prospective experimental study involving 750 samples (350 patient, 400 environmental).
- Screening for biofilm, lipase, α-amylase, proteinase, haemolysin, phospholipase, and pectinase using standard microbiological methods.
- Statistical analysis performed using Chi-square test and SPSS software.
Main Results:
- All tested virulence factors were produced by reference strains (ATCC controls).
- Patient isolates showed higher prevalence of α-amylase (89.74%), proteinase (87.17%), and biofilm (82.05%) compared to environmental isolates.
- Statistically significant differences (p<0.05) in virulence factor distribution were observed between patient and environmental samples.
Conclusions:
- Aspergillus species from patients exhibit a greater presence of virulence factors than those from the environment.
- Findings suggest potential transmission of Aspergillus from the environment to patients.
- Detection of virulence factors aids in differentiating pathogenic from non-pathogenic strains, guiding clinical treatment decisions.
