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Published on: February 14, 2018
Paradoxical echinocandin activity: a limited in vitro phenomenon?
1University of Texas at Austin College of Pharmacy, Austin, Texas 78229, USA. wiederholdn@uthscsa.edu
Medical Mycology
|March 4, 2009
Summary
Echinocandins show reduced effectiveness at high doses, a paradoxical effect seen in vitro against fungal infections. Clinical significance remains unknown, but understanding it may improve antifungal treatments.
Area of Science:
- Mycology
- Pharmacology
- Infectious Diseases
Background:
- Echinocandins are vital for invasive fungal infections, offering a good safety profile.
- A paradoxical effect, where echinocandin activity decreases at higher concentrations, has been observed.
- This effect varies by fungal species and echinocandin drug.
Purpose of the Study:
- To investigate the paradoxical effect of echinocandins on fungal infections.
- To explore potential mechanisms and clinical implications of this phenomenon.
Main Methods:
- In vitro studies examining echinocandin activity against Candida and Aspergillus species.
- Analysis of potential cellular pathways and markers involved in the paradoxical effect.
Main Results:
- The paradoxical effect has been reported in vitro against Candida and Aspergillus.
- Potential mechanisms involve the protein kinase C pathway and increased cell wall chitin.
- Increased galactomannan has been observed, but in vivo findings on fungal burden are inconsistent.
- The paradoxical effect has not been clinically demonstrated.
Conclusions:
- The clinical relevance of the paradoxical echinocandin effect is currently unknown.
- Further research is needed to understand fungal responses to echinocandin-induced cell wall damage.
- Understanding this effect could lead to improved antifungal treatment strategies.
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