Geosmithia spp

From Dog
Microscopic morphology of Geosmithia argillacea (lactophenol cotton blue stain)[1]

Geosmithia are a saprophytic, opportunistic anamorphic (mold-like) thermophilic, filamentous fungus in the Trichocomaceae family.

This fungus normally resides in rotting vegetation, causing 'thousand cankers disease' in species of walnut trees. Airway colonization by G. argillacea has recently been reported in humans and is commonly seen in patients immunocompromised with tuberculosis[1].

Microscopically, this fungus resembles Penicillium spp but is genetically dissimilar[2].

Species which are pathogenic to dogs include:

  • Geosmithia argillacea

Disseminated infections have been reported in a German Shepherd[3].

Sensitivity to amphotericin B, voriconazole, itraconazole and posaconazole have been reported.


  1. 1.0 1.1 Sohn JY et al (2013) Isolation and identification of Geosmithia argillacea from a fungal ball in the lung of a tuberculosis patient. Ann Lab Med 33(2):136-140
  2. Sigler L et al (2010) Phialosimplex, a new anamorphic genus associated with infections in dogs and having phylogenetic affinity to the Trichocomaceae. Med Mycol 48(2):335-345
  3. Grant DC et al (2009) Disseminated Geosmithia argillacea infection in a German shepherd dog. Med Mycol 47(2):221-226