Tuesday Case Conference

1. Tuesday Case Conference

2. History 67 yr old man, former smoker, with h/o stage I poorly differentiated NSCLC s/p RML resection in 1996. He is followed with annual surveillance chest CT�s which have all been negative. However, in May 2002 he has an abnormal CT. Denies cough, CP, SOB, F, C, NS or wt loss

3. PMHx: CAD s/p PTCA with stent Pneumonia in 2/2002 Hyperlipidemia HTN Medications: ASA Prinivil Pravachol Metoprolol

4. Labs: 13.7 52% PMNs 4.3 293 41.4 139 102 14 4.3 25 0.9 LFTs normal Coags normal Exam: T98.7 BP167/78 P65 RR16 100% on RA 71 kg Gen: NAD A+Ox3 HEENT: WNL No palpable LN CV: RRR no M/G/R Lungs: CTA bilat Abd: SNTND, nl BS Ext: No CCE Neuro: WNL

7. CT report: Precarinal lymph node, enlarged since prior study, measuring 1.9 x 2.4 cm.

8. CT report: Precarinal lymph node, enlarged since prior study, measuring 1.9 x 2.4 cm. Differential Diagnosis? Next step?

10. CT report: Slight interval increase in size of precarinal lymph node, now measuring 2.2 x 2.7 cm. No new mediastinal or hilar adenopathy is identified.

11. CT report: Slight interval increase in size of precarinal lymph node, now measuring 2.2 x 2.7 cm. No new mediastinal or hilar adenopathy is identified. PET: Fairly intense uptake is identified within the known precarinal lymph node, otherwise negative.

17. Pulmonary Nocardiosis

18. Nocardia: Microbiology

19. Actinomycetes Anaerobic Aerobic Actinomyces Nocardia Arachnia Gordona Rothia Streptomyces Bifidobacterium Mycobacterium Rhodococcus Corynebacterium Actinomadura Dermatophilus

20. Nocardia: Species N. asteroides (80% of human infection) N. brasiliensis N. farcinia N. nova N. otitidiscaviarum N. transvalensis

21. Nocardia: Epidemiology Nocardia is a ubiquitous soil bacteria. Nocardiosis is rare. It is estimated that there are 500 to 1000 new cases per year in the U.S. There are several predisposing conditions, although 36% of cases had no predisposing in one series.

22. Extrapulmonary Nocardiosis

23. Pulmonary Nocardia: Clinical Presentation Symptoms are can be progress over several weeks. Low grade fever Weight loss Productive cough Hemoptysis Fatigue Pleuritic chest pain

24. Radiographic appearance is variable

25. Nocardia Diagnosis Several factors can make the diagnosis difficult: Slow growth (up to 2 to 3 weeks) Over growth of other contaminating organisms Lack of specific clinical or radiographic characteristics In one series 44% of patients with pulmonary nocardia required an invasive procedure to make the diagnosis (bronchoscopy, thoracentesis, thoracotomy, autopsy). Sensitivity of invasive sample estimated at 90%. Clinically insignificant colonization of nocardia has been reported.

26. Nocardia Treatment Lack of clinical trials makes optimal treatment unclear. Sulfonamides, especially TMP-SMZ, considered to be the drug of choice. Optimal dose unclear, most recommend 2.5-10 mg/kg of TMP and 12.5-50 mg/kg of SMZ (1 to 4 DS tabs per day). Duration of therapy also not known. Most recommend 2 to 12 months.

27. Nocardia Treatment Alternative treatments bases on in vitro activity and anecdotal success. Informal poll of IDSA members suggests: Severely ill: IV amikacin, imipenem or 3rd gen cephalosporins. Less ill: Oral minocycline

28. Prognosis Prognosis depends on extent of disease and immune status of the patient. For disseminated nocardiosis the mortality is 7 to 44% in immunocompetent patients; mortality is >85% in immunocompromised patients.

30. Conclusions Nocardia is a rare cause of pulmonary infection Would consider in immunocompromised patient with subacute or chronic symptoms CXR often shows bilateral nodules, but can present in different patterns Optimal treatment not known, TMP-SMZ most commonly used