6TB History1020 – Ibn Sina [ Avicena ] described in first as contagious diseaseSenabsin - name Tuberculosis1859 – First sanatorium in Germany1882 – R.Koch found bacilli1905 – Nobel Price1906 – A. Galmette and Camele Gurien – first immunisation
7TB History 1907 – National TB Association founded in US and Canada – First human vaccination used in France– Streptomycin was developed80’s – Drug resistance appearedThe 20th _ TB kill’s more than 100 million people
8Incidence 8,8 million new cases and 1,4 million died in 2010. 19-43% of the world`s population areinfected by M.Tuberculosis.>95% of cases occur in developingcountries.
46TB in ChildrenUnder 5year triad of close contact, positive TST, suggestive findings on the x-ray [ primary complex, opacification with hilar or subcarinal lymphadenopathy ] or physical examination are useful for diagnosis for active TBGastric aspiration
52Tuberculin test (Mantoux) Intradermal injection of 5 TU (tuberculin units) of purified protein derivative (PPD).Induration measured after hours.Booster [ two step testing ]Conversion: an increase of 6-10mm to >10mm.
53Booster Response, Conversion Booster – 10mm or more and has increased by 6mm since the previous in the absence of exposure. Lover risk than initial positive TSTConversion – 10mm or more and has increased by 6mm since the previous up to 8weks after initial negative TST in the setting of recent exposureReaction 10 and more mm should be referred for medical evaluation to exclude active TB
60Potential causes of false negative Tuberculin test : Technical - correctible Tuberculin material : improper storage [ exposure to light, heat ], contamination, improper dilution, chemical denaturationAdministration: injection of too little tuberculin, or too deeply, or more than 20 minutes after drawing up into the syringeReading: inexperienced or biased reader, error in recording
61Potential causes of false negative tuberculin tests: Biologic – not correctible Infections: Active TB [ especially if advanced ], bacterial infections[ typhoid fever, brucellosis, typhus, leprosy, pertussis ]. HIV inf[ especially if CD count less than 200 ], viral infection [ measles, mumps, varicella ], fungal infection [ blastomycosis ]Live virus vaccination : measles, mumps, polioImmunosuppressive drugs : corticosteroids, TNF inhibit, othersMetabolic disease: CRF, severe malnutrition, stress [ surgery, burns ]Diseases of lymphoid organs: Lymphoma, CLL, SarcoidosisAge under 6 months, elderly
63LTI Diagnosis IGRAs Specificity 95%, Sensitivity 80-90% TST - Specificity 97% in non BCG, and 60% in BCG administered, Sensitivity -80%IGRAs sensitivity is diminished in HIV with lower CD4 [ TSPOT is less affected ]M.Kansasii, M.Marinum affect
64LTI Diagnosis USA – IGRAs used, but not in addition to TST Canada – IGRAs is appropriated in the setting of negative TSTUK – TST is the first-line test. If positive – may be considered IGRA depending of BCG status