Presentation on theme: "W. J. Fenton MD, FRCPC, FACP Clinical Professor of Medicine, U of S TB 101 for Primary Care Providers."— Presentation transcript:
W. J. Fenton MD, FRCPC, FACP Clinical Professor of Medicine, U of S TB 101 for Primary Care Providers
TBC & partners have always put the patient first: Mobile clinics Try to be flexible concerning drug delivery Incentives if need be In all we do collectively, we constantly should strive to make the patient first in our thinking and our actions.
While you are thinking ….
If you are dealing with TB – THINK HIV TBC tests for HIV in those we see with a positive TST age 14 and up If you are dealing with HIV – THINK TB
Look for Early TB
Cough 4/52 or more (If a smoker look for persistent change in cough of 4/52) Unexplained fever of > 1/52 Antibiotic resistant pneumonia (on CXR) May not be TB but check for it: sputum CXR
Specimens help to: – Confirm/exclude diagnosis Without a + culture the diagnosis remains presumptive – Identify the organism – Identify drug sensitivities
Get Specimens “If they are coughing get sputum” – do it now while they are in clinic – but also try to get some morning sputa 3 AM sputa maximizes yield Consider inducing the sputum if necessary With Miliary TB may also consider urine, bone marrow With very low CD4 count consider blood culture for TB
Understand the Limitations of Radiology
CXR & CT are crucial parts of TB evaluation BUT
Understand the Limitations of Radiology CXR & CT finding may suggest TB but do not prove it – e.g. recent case Normal CXR does not exclude active TB – (Marciniuk Chest 1999;115: ) TB has typical patterns but can look like anything on CXR
Look at the Whole Picture
As with any illness, look at the whole picture don’t just treat a test. history physical tests, CXR’s environment
Focus of Contact Tracing
Primary TB – looking for someone who is coughing (looking for source) - age 15 & up Active smear + (culture +) TB – looking for spread - age <5 - HIV+, other immunosupression
Never Monotherapy Monotherapy will inevitably lead to drug resistance
Why two drugs? The organisms in a large active population e.g. cavity, will innately have some organism resistant to a drug. The chance of an organism being resistant to two drugs is so small as to be non-existent. When starting active treatment, want two drugs that the person has not been previously exposed to
How treatment failure can occur
Treatment Failure Non-compliance No drugs work if you don ’ t take them Large rapidly growing population - selection of resistant organisms Must have at least two drugs the organisms are sensitive to Prescription error Patient decides to delete one drug Slow growing population - persistent organisms Drugs not continued long enough Long enough but not enough doses in the alotted time
Where TB organisms live
Location Vs Drug Effectiveness Activity on organisms CavityMacrophCaseum SM+++00 INH+++0 RMP++++ EMB+/-+/-0 PZA0++0
Activity of First-Line Drugs
Cochrane Review trashed it!
407 cases of SAT, then switched to 581 of DOT, results are despite higher IV drug use, more homelessness and rising TB rates Weis et al NEJM 1994;330: DOT Identifies compliance issues quickly (audit) Ensures drugs are taken together
Active Disease Risks 20-30%2-5x20-30x 100+x Granuloma on CXR(2)fibronodular on CXR (6-19) HIV infection (50-110) Smoke 1 ppd(2-3)TB infection within 2 yrs (!%) AIDS ( ) infected age 0-4 (2.2-5)CA head & neck (16) <90% ideal wt (2-3)CRF on hemodialysis (10-25) DM (2-3.6)silicosis (30) TNF inhibitors (1.5-4)Transplantation (20-74) CS Rx (4.9) Untreated TB infection Compared with infected person with No risk factors & normal CXR
Active TB Risk Factors
Infection Risks Can Stds P 65
TST Screening & BCG status Saskatchewan study comparing young kids who had or did not have neonatal BCG vaccination: At age 4 – no difference – TST 10 mm valid < age 4 -TST 15 mm valid TST < 15 “grey area” consider community & age risk Reid et al: Chest 2007;131;
Can doctors or nurses predict which patient will be compliant with medications use?
What is this?
6 months earlier
* usually resolves spontaneously * active TB will develop in up to 60% * usually unilateral *more common in young men * DTH reaction to a few bacilli * smear negative fluid, culture positive in only 1/3 *pleural biopsy for diagnosis * Induced sputum may be positive Tuberculous Pleural Effusion
How does HIV change TB Management
Test for HIV – All active TB cases – Contacts if at risk for HIV – Contacts if index cases is HIV-TB co-infection TST – 5 mm is positive IN HIV+ PATIENT – Sensitivity decreases as CD4 count decreases
How does HIV change TB Management Active TB in HIV+ – May lack typical clinical & CXR features More LN, pleural, meningeal, pericardial involvement CXR may be normal – Aggressive sampling Sputums even if CXR normal Blood culture if CD4 < – If negative TST, consider repeat after ART & immune reconstitution
How does HIV change TB Management LTBI in HIV+ – Treat unless well documented previous treatment – ? Benefit of Rx in TST- or anergic HIV+ – HIV+ with recent infectious TB exposure – treat for LTBI regardless of TST status High re-infection risk in HIV+ – Consider LTBI Rx for HIV+ TST-: High epidemiologic risk CXR features suggest past TB – Treat LTBI in pregnancy
How does HIV change TB Management Tx of TB in HIV+ – The good news – for fully sensitive TB the following are the same as in HIV- cases: Cure rates Clinical response rate Culture conversion time Relapse rates
How does HIV change TB Management Tx of TB in HIV+ – RMP (rifamycins) very important – BUT.. RMP interferes with some AR drugs TB & HIV docs need to connect – Rx for 9/12 may be wiser than shorter courses – If CD4 <100 do not use RMP less than 3x/wk Increased RMP resistance – ? Reduced absorption of RMP & EMB in HIV+ – DOT is standard – HIV+ may be more prone to INH neuropathy B6 25 mg – Initiate ART early
If you want things to happen (want service)
Phone Don’t just send a letter or requisition e.g. x-ray req’n