nocardia and actinomyces

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nocardia is weakly acid fast, aerobic
actinomyces is not acid fast, anaerobic
nocardia nova complex: asteroids
skin lesions, lung lesions
now with PCR techniques and MALDI-TOF to identify
may be resistant to bactrim
For mild-to-moderate pulmonary nocardiosis in the immunocompetent host, TMP-SMX is usually the drug of choice. In the case of severe infection, and/or if there is CNS involvement, initial treatment should include 2 to 3 intravenous agents while susceptibility testing is pending, TMP-SMX plus amikacin or with the addition of imipenem for CNS disease.
if CNS involvement use bactrim + meropenem + amikacin
After 3 to 6 weeks of IV therapy and, depending on the response, sensitivity results, treatment can be switched to oral therapy, usually high-dose TMP-SMX. Treatment should be continued for 6 to 12 months (12 months in the immunocompromised). In patients with chronic immunosuppression, lifelong indefinite secondary prophylaxis is usually indicated. If a sulfa allergy exists, desensitization is recommended.

anaerobic, beaded, branching gram positive bacteria
immunocompentent as opposed to immunocompromised with nocardia
can be fatal if not treated
sulfur granule pathognomonic¹
branching and filamentous gram-positive rod that does not grow aerobically on blood or Sabouraud agar and is not acid fast with routine or modified staining
identical gram stain to Nocardia but will not grow aerobically and not acid fast staining²