Case 178. Alternariosis (48 y-o F)

　 　 　 　
　 Biopsy from an infiltrative and ulcerative, nodular skin lesion on the knee, lasting for 13 years 　
　 　 　 　

　

 　 Immunostaining using a 1:500 diluted patient's own serum discloses a positively labeled round pathogen in the abscess cavity (indirect immunoperoxidase).