Case 179. Protothecosis (66 y-o M)

       
  Biopsy from an irregular infiltrative nodule on the dorsum of the hand of a farmer who cultivates Japanese oranges  
       

 

  Protothecosis is a rare infection by achlorophilic algae, resulting from traumatic innoculation. Epithelioid granulomas with central necrosis are formed in the dermis (HE).