• ubiquitous worldwide distribution
• organisms acquired by:
  • inhalation
  • cutaneous inoculation
• infection can cause necrosis and abscess formation

• strict aerobic bacilli with branched filaments
• gram pos., but stain poorly
• cell wall has mycolic acids
• partially acid fast
• produces catalase
• growth may require one week

• opportunistic infections among patients w/
  • leukemia
  • solid organ transplant
  • corticosteroids
  • AIDS

• pulm disease (usually by N asteroides)
• CNS infection
• skin infections
• ocular infections

• single or multiple brain abscesses
• CNS disease may be initial or sole presentation of a late complication of pulmonary infection

• mycetoma
• lymphocutaneous subQ abscess
• cellulitis
• hematogenous spread

Sinus tract formation can occur with chronic infections

• N. brasiliensis
• N. otitidiscavarium

• gram positive stain (but stain poorly)
• partially acid fast
• grow on most lab media with 5-10% CO₂
• selective media: buffered charcoal yeast extract agar
• may need about a week to culture on medium

• antibiotics- remember N. farcinica resistant to sulfa agents
• surgical debridement

• part of normal colonization of:
  • upper resp. tract
  • GI tract
  • female genital tract
• low virulence potential but can cause disease when mucosal barriers are disrupted

• infection usually endogenous
• no evidence for disease from person to person spread or acquisition from external soruce (soil, water)

• non spore forming gram positive bacilli
• form branching filaments
• facultative and strict anaerobes
• not acid fast
• grow slowly in culture

Those in bold differentiate them from Nocardia

• A. israelli
• A. naeslundii
• A viscosus
• A odontolyticus
• A pyogenes
• A meyeri

• cervicofacial aka lumpy jaw
  • extension of organisms through the mouth and out to the cheek
  • can cause prominent or subtle swelling
  • if you push it out, you could get sulfur granule
• lung- aspirate flora and cause lung infection
• abdominal
• pelvic (ex: rectal abscess)
• CNS

• sulfur granules (seen on washings with Papinicolau stain, Brown and Hopps stain, methenamine silver stain, Splendore Hoeppli stain)
• thin, gram positive branching bacilli
• fastidious and grows slowly under anaerobic conditions
• may take more than two weeks for culture growth
• molar colony appearance on agar

• characterized by multiple abscesses connected by sinus tracts with macroscopic sulfur granules
• suppurative areas are surrounded by fibrosing granulation, causing hard or woody induration

• tx- penicillin
• surgical debridement