Cladosporium species recovered from clinical samples in the United States
August 19 2015
Cladorsporium species are some of the most frequently identified fungi in the environment, having small conidia which can easily be disseminated in the air. They are frequently associated with allergic rhinitis and superficial lesions, but can sometimes cause systemic infection.
A study by Sandoval-Denis et al attempted to identify species of Cladosporium in clinical samples. C. halotolerans was the most frequently identified species (14.8% of samples), followed by C. tenuissimum (10.2%) and C. subuliforme (5.7%). Most strikingly, 39.8% of samples did not match any known taxa and represent at least 17 new Cladosporium species.
Most common anatomical sites for isolation were the respiratory tract (54.5%, mostly from bronchoalveolar lavage and nasal samples), and superficial sites (28.4%). The percentages were similar across all identified species.
Given the recent taxonomical debate surrounding Cladosporium, it is unsurprising to see new species identified and two recently described C. toxicla and C. penidiella seen for the first time in clinical samples. However, the number of new species identified from a relatively small sample size is suggestive of further research being needed. Many more species may await discovery.