Nocardia species

Background

Microbiology

• Beaded Gram-positive partially acid-fast bacillus
• Appearance similar to Actinomyces, differentiated by acid fast staining (Actinomyces is not acid fast)

Management

• Mild to moderate: TMP-SMX
  • Immunocompetent: 5-10 mg/kg split tid to qid
  • Immunocompromised: 15 mg/kg split tid to qid
• Severe: TMP-SMX plus either amikacin or imipenem
• Other antimicrobials include ceftriaxone, minocycline, and linezolid

Duration

• Isolated cutaneous infection in immunocompetent host: 3 to 6 months
• Isolated cutaneous infection in immunocompromised host: 6 to 12 months
• Serious pulmonary infection: 6 to 12 months or longer
• Any non-cutaneous disease in immunocompromised host: at least 12 months, and possibly lifelong suppression