TB Classification (ATS/CDC)

Transcription

1 bits and pieces Lisa Chen, MD UCSF Pulmonary/Critical Care Curry International Tuberculosis Center 10/2017 TB Classification (ATS/CDC) TB0 No tuberculosis exposure, not infected TB1 Tuberculosis exposure, no evidence of infection TB2 Latent tuberculosis infection, no disease TB3 Tuberculosis, clinically active TB4 Tuberculosis, not clinically active ( abnormal CXR ) TB5 Tuberculosis suspect (diagnosis pending)

2 Can this be TB? Old/healed TB Ca+ granuloma - Ghon lesion Ca+ granuloma and hilar node calcification - Ranke complex Apical pleural thickening Fibrosis and volume loss Case 2: Patient A 42 yo male, recent immigrant from Philippines No PMX, HIV neg, +tobacco, no symptoms No hx prior TB, BCG unknown to pt. Immigration CXR Next? TB 5 (low), PPD 14mm, smear neg x3 No rx

3 Case 2: Patient B 76 yo male from China (in US since 1979) Cough x two weeks, 60 pk/yrs tobacco Hx treated TB in China 1953 No other medical risks CXR Next? TB 5 (low), QFT+, smear neg x3 No rx Case 2: Patient C 63 yo male, recent immigrant from China B2 class, treated TB 1965 in Taiwan, No PMHX, 50 pk/yr tobacco No symptoms Immigration CXR Next? TB 5 (low), QFT+, smear neg x3 No rx

4 Case 2: Any positive culture results? A Yes, TB 3 pansensitive B No, TB 4 C Yes, TB 3 pansensitive Check sputums! Case 2: Are you done? B No, TB 4

5 LTBI Treatment : Abnormal CXR (TB4) TB suspect/ppd+ Abnormal CXR Smear neg x3 Low suspect No rx (CXR unchanged) = TB4 CXR / sx improved (INH)RIF x 4 mo INH x 9 mo High suspect Rx: I/R/P/E CXR unchanged = TB4 Treatment done Months: At 2 mo the cultures are negative New 2007 Technical Instruction for Immigration TB screening

6 Division of Global Migration and Quarantine 2007 Immigration TI Classification Normal screen no classification Class A TB disease, no immigration w/o rx (some waiver / exceptions) Class B1 TB, Pulmonary: No treatment hx/sx/hiv/ or CXR suggestive, but smear and culture neg Completed TB treatment Class B1 TB, Extrapulmonary Class B2 TB: LTBI eval.(ppd >10) no active TB) Class B3 TB: Contact eval Treatment All pulmonary/laryngeal TB must be treated prior to arrival (use ATS/CDC/IDSA guidelines) Contacts should be evaluated for active TB (start LTBI overseas only in <5yo and HIV)

7 Case 1: TB or Not TB? 39 yo woman Recently from China - PPD 12 mm - No symptoms Offer INH? Check sputums? Smear/culture neg x3 Classified TB4 Refuses rx

8 Case 1: TB or Not TB? One year later, with symptoms In high-risk groups, even the small stuff can matter. Targeted testing of Documented Immigrants Old Technical Instructions: CDC classification system for TB status before immigration hx/exam/sx/cxr Suspicious CXR = three sputum smears Class A Active case of TB (smear positive), contagious, not cleared for further travel Class B1 CXR suspicious for active TB, not infectious (smear negative) Class B2 CXR suggests inactive TB, not infectious (no smears done)

9 Targeted testing of Documented Immigrants Old TB classification for immigration was determined by x-ray and sputum smears only, (not cultures) Class B1 and B2 immigrants are allowed to enter the country, but they must report to a state-designated health officer within 1 month of arrival in the U.S. (NOT MANDATORY) A high rate of active TB is found in Class B pts. (higher yield than contact investigation!) TB immigration classification San Francisco Program Data ( 95-97) Class B-1: clinically active not infectious n= % Class B-2: not clinically active, not infectious n= % Final TB Classification Final TB Classification TB 0 n= % TB 2 n= % TB 3 n=24 8.0% TB 4 n= % TB 0 n= % TB 2 n= % TB 3 n=5 0.8% TB 4 n= %

10 Case 3: TB or Not TB? 30 yo woman, moved to US from India 4 yrs ago Needs clearance to work in school TST 12 mm No symptoms What would you do next? A. Collect three sputum for AFB/ culture? B. Begin treatment for LTBI with INH? C. Repeat the skin test? D. Repeat the CXR in 6 months? Anything else?

11 After two months of INH/RIF/PZA/EMB: Sputum smears/cultures for AFB are negative What would you do next? A. Obtain a CT scan B. Repeat CXR C. FNA the nodule D. Bronchoscopy for better samples Now what? Treatment of Culture-negative TB Low suspect No rx CXR unchanged = TB4 (INH)/RIF x 4 mo TB suspect/ppd+ Abnormal CXR Smear neg x3 INH x 9 mo CXR / sx improved = Culture neg. case TB INH/RIF x 2 more mo** High suspect Rx: I/R/P/E CXR unchanged = TB4 Treatment done Months: At 2 mo the cultures are negative **Guidelines, but.