Pulm. UW mainly + Mehlm: TBC 03-11 (3) Flashcards
UW. table. What about risk in CKD?
These patients are at increased risk due to impaired cellular mediated immunity
Same reason why they get TST anergy (false negative)
UW. table. Risk factors? 4
Immunosupression
Travel from endemic area
Exposure to infected household contact
Resident/employee of prison, homeless shelter, health care facility
UW. table. Risk factor, what is the most common behavioral?
Substance abuse
UW. table. Clinical?
Chronic cough, prolonged fever, weight loss, failure to thrive
UW. table. Diagnosis. tests. 2
Positive screening PPD OR interferon gama release assay
UW. table. diagnosis. what is seen xray?
Hilar adenopathy, effusion, consolidation, cavitation
UW. table. diagnosis. culture?
Positive AFB (acid-fast bacilli) and mycobacterial culture
UW. Primary. what pneumonia? granulomas?
Lobar pneumonia with cavitation
Caseating granulomas
UW. Primary. xray?
Ghon focus
UW. Primary. what symptoms in older?
nonspecific.
anorexia, muscle waisting, weight loss
UW. Primary. chronic cough definition?
chronic cough > 8 weeks in adult
>4 weeks in children
UW. Primary. Labs?
Anemia (of chronic disease)
Monocytosis
Hypergammaglobulinemia (incr. total protein)
Hypoalbuminemia (inflammatory cytokines stimulate production of acute phase reactants at the expense of albumin)
UW. Primary. what patients are at risk of progressive primary TB?
renal disease, DM, HIV, advanced aged, immunosuppressive medications
UW. Latent. what diagnostic tests?
Positive IGRA and TST and negative CXR and absence of symptoms.
UW. Latent. treatment options.
UW. Latent. treatment options. If 3 months?
ISONIAZID and RIFAPENTINE weekly for 3 months under direct observation
UW. Latent. treatment options. what therapy is not recomended in HIV patients?
ISONIAZID and RIFAMPICINE weekly for 3 month
UW. Latent. treatment options. what option for 6-9 months?
Isoniazid
UW. Latent. treatment options. what option for 4 months?
Rifampin
UW. Reactivated TB. clinical?
fever, night sweats, weight loss, cough with blood
UW. Reactivated TB. what 2 epidemiologic facts?
Emigration from endemic areas.
Risk is highest for those who lived in the USA for 5 years or less
UW. Reactivated TB. can be colonized by what?
Can be colonized by aspergillus species creating an aspergilloma.
UW. Reactivated TB. diagnosis xray?
CXR: apical cavitary lesion.
Due to higher oxygen tension and slower lymphatic elimination.
UW. Reactivated TB. treatment. first step?
stabilize the patient
UW. Reactivated TB. treatment. isolation?
respiratory isolation (airborn precaution)
UW. Reactivated TB. treatment. RIPE?
2 months of RIPE and 4 months of rifampin and isoniazid.
Rifampicin
Isoniazid
Pyrazinamide
Ethambutol
UW. Reactivated TB. treatment. Rifampin adverse?1
Rifampin: orange discoloration of secretions.
UW. Reactivated TB. treatment. Isoniazid adverse? 3
Isoniazid: peripheral neuropathy (stock and glove numbness and tingling), vitamin b6 deficiency causing vitamin b3 deficiency, and hepatotoxicity
UW. Reactivated TB. treatment. what patients population is at highest risk for vit B6 deficiency?
Patients with malnourishment, pregnancy, or certain
comorbid illnesses (DM) are at a high risk of vitamin B6
deficiency –> prophylactic supplementation.
UW. Miliary TB. spread?
Lymphohematogenous spread of mycobacterium tuberculosis.
UW. Miliary TB. may arise with..? 2
May arise with primary infection or reactivation.
UW. Miliary TB. what symptoms?
Subacute or chronic symptoms are common.
UW. Miliary TB. what extrapulmonary symptoms? 4
LNs, liver, bones, and CNS.
UW. Miliary TB. diagnosis? xray
diffuse reticulonodular pattern (“millet-seed”).
UW. Miliary TB. diagnosis. what ,,lab” testing? 2
They’re often immunocompromised so interferon-based testing (IGRA
and tuberculin skin testing).
UW. Miliary TB. diagnosis. biopsy what parts?
Lungs, blood, or tissue biopsy.
UW. TBC. Asymptomatic screening. In what all patients?
All newly diagnosed HIV should be screened for TB.
UW. TBC. Asymptomatic screening. PPD results based on induration. >/= 5 mm? in what patients?
HIV/AIDS, chemo, transplant, close contacts, or anergy
UW. TBC. Asymptomatic screening. PPD results based on induration. >/= 10 mm? in what patients?
healthcare providers, prison, homeless, or travel
UW. TBC. Asymptomatic screening. PPD results based on induration. >/= 15 mm? in what patients?
soccer mom
UW. TBC. Asymptomatic screening. IGRA can be done instead of PPD. what result eg in BCG vaccine?
IGRA does not give a false positive with BCG.
UW. TBC. Asymptomatic screening. IGRA can be done instead of PPD. minimal response in what conditions?
A minimal response to control antigens is most often seen with lymphocyte immunosuppression due to HIV or the use of the
immunomodulatory medications (discontinue them a couple of weeks before doing the test).
UW. TBC. Asymptomatic screening. Positive PPD. whats next?
xray
UW. TBC. Asymptomatic screening. Negative PPD. whats next?
annual screen or 2-tier test.
UW. TBC. Asymptomatic screening.
Patients with CKD will have a negative TST cannot rule out active TB infection.
.
UW. TBC. Asymptomatic screening.
Both interferon-based testing and tuberculin skin testing can be falsen negative.
.
UW. TBC. Asymptomatic screening. negative xray?
Negative –> latent TB.
● Treatment: isoniazid and vitamin b6 for 9 months.
● Rescreen yearly with CXR.
UW. TBC. Asymptomatic screening. positive xray?
AFB smear.
UW. TBC. Asymptomatic screening. AFB smear. how is performed?
AFB smear: 3 early morning samples 24 hours apart.
UW. TBC. Asymptomatic screening. AFB smear - negative?
latent
UW. TBC. Asymptomatic screening. AFB smear - positive?
active TB
—> treatment RIPE
UW. TBC. Asymptomatic screening. AFB smear.
TB cannot be ruled out from a single negative AFB result.
.
UW. TBC. SYMPTOMATIC screening. what first steps?
start with CXR and confirm with AFB.
UW. TBC. SYMPTOMATIC screening. positive xray –>?
confirm with AFB.
airborne precaution and RIPE.
UW. TBC. SYMPTOMATIC screening. Positive xray –> negative AFB –>?
latent TB –> isoniazid and B6 for 9 months.
UW. TBC. SYMPTOMATIC screening. Negative xray –> AFB negative–>?
something else, not TBC
UW. TBC. SYMPTOMATIC screening. Negative xray –> AFB positive on culture –>?
nontubercular mycobacteria.
UW. TBC. SYMPTOMATIC screening. what perform if pleural effusions present?
thoracentesis –> adenosine deaminase positive.
UW. TBC. SYMPTOMATIC screening. what is the last resort of diagnostic?
NAAT PCR is a very last resort to ELIMINATE TB as a possibility.
UW. TBC. SYMPTOMATIC screening. how to take sample from children?
Children who cannot generate sputum –> do gastric lavage which recover M. tuberculosis from the swallowed secretions.
UW. Diagnostic tests table. AFB smear microscopy. price, sensitivity?
Low cost and rapid (minutes to hours)
Low sensitivity because high burden of mo/s required in sample (>10 000/ml).
UW. Diagnostic tests table. AFB smear microscopy. what can/cannot differentiate?
CANNOT differentiate TB from non-TB mycobacteria
UW. Diagnostic tests table. Nucleic acid amplification testing. cost, sensitivity?
Higher cost, slightly less rapid (1-2days)
Higher sensitivity (only 10 bacilli/ml required for positive test)
UW. Diagnostic tests table. Nucleic acid amplification testing. how about differentiation?
CAN differentiate TB from non-TB mycobacteria
UW. Diagnostic tests table. Sputum culture. in general?
GOLD STANDARD
Quantitative and allows for drug sensitivity testing
Slow - takes 3-8 weeks.
UW. Diagnostic tests table. what is gold standard?
Sputum culture.
UW. Diagnostic tests table. what allows for drug sensitivity?
Sputum culture.
UW. Diagnostic tests table. which CAN differentiates TB and nonTB mycobacteria?
Nucleic acid amplification testing.
UW. Diagnostic tests table. which CANNOT differentiate TB and nonTB mycobacteria?
AFB smear microscopy
UW table. PPD/TST induration table. >=5 mm. what patients to treat?
HIV-positive patients
Recent contact of known TB case
Nodular or fibrotic changes on xray consistent with previously healed TB
Organ transplant recipients and other immunosuppressed patients
UW table. PPD/TST induration table. >=10 mm. what patients to treat?
Recent immigrants (<5years) from TB endemic areas
Injection drug users
Residents and employess of high-risk settings (prisons, nursing homes, hospitals, homeless shelter)
Mycobacteriology lab personnel
High risk for reactivation TB (DM, prolonged corticosteroid therapy, leukemia, ESRD, chronic malabsorption syndromes)
Children < 4y/o, or those exposed to adults in high-risk categories
UW table. PPD/TST induration table. >=15 mm. what patients to treat?
All of above plus healthy individuals
Ghon focus?
granuloma
Ghon complex?
Ghon focus + lymphadenopathy
Latent infection?
Dormant bacteria contained within walled-off foci
LATENT infection –> reactivated bacteria spread bronchogenically and cause extensive cavitation (IT IS CALLED SECONDARY TBC) ———–> spread to other organs (hematologic dissemination)
.
RESOLUTION?
Bacterial clearance and scar formation
PROGRESSIVE PRIMARY TBC = Failed immune response results in progressive lung consolidation and necrosis –> milliary TBC –> spread extrapulmonary (hematologic dissemination)
.
M. first Dx test?
PPD
M. first Dx test if Hx of BCG vaccine?
IGRA
M. PPD/IGRA positive –> next best step?
chest x ray
M. xray positive –> next best step?
Tx of active TB
M. PPD/IGRA positive –> x ray negative -> next best step?
Tx of latent Tb/prophylaxis of TB
M. what need to add if isoniazid is used for Tx?
pyridodine (vit B) - to prevent neuropathy
M. when after exposure, culture is positive?
2-5 weeks
M. >-5 mm one more population not mentioned before?
Use prednisone (1,5 mg day for 1 month); also anti-TNF alfa use
M. Disseminated (miliary), what organs?
PSOAS abscess, POTT disease (TB in vertebral), adrenal insuff, meningitis, arthritis, osteomyelitis