Gram-ghost bacilli

J Gen Fam Med. 2018 Oct 5;20(1):31-32. doi: 10.1002/jgf2.212. eCollection 2019 Jan.


A 76-year-old man presented with a 3-day history of a productive cough and right chest pain on inspiration. The Gram stain of the sputum showed unstained bacilli and polynuclear leukocytes, suggesting a diagnosis of pulmonary acid-fast bacillus infection. Mycobacteria can be identified by Gram staining and are reported to be Gram-neutral or Gram-ghost, and recognition of Gram-ghost bacilli in the initial specimen may assist in distinguishing mycobacterial infection from community-acquired pneumonia.