PPS Tb Guidelines Flashcards
MDR-Tb
Resistant to at least isoniazid and rifampin
XDR-Tb
Resistant to HR + Fluoroquinolone + at least 1 second-line injectable agent (amikacin, kanamycin, and/or capreomycin)
Primary mode of transmission of Tb bacilli
Airborne droplet nuclei
Tb transmission from children aged less than ___ is rare, since most children cannot expectorate sputum
10
Associated with virulence of Tb bacilli
1) Trehalose dimycolate (cord factor) 2) Sulfatides
Responsible for morphologic appearance of cell serpentine cords of Tb bacilli in close, parallel arrangements
Cord factor
Peripherally located glycolipids that inhibit fusion secondary lysosomes with Tb bacilli-containing phagosomes within a macrophage, possibly promoting INTRACELLULAR SURVIVAL of the organisms
Sulfatides
Gold standard for diagnosis of Tb
Demonstration/isolation of the organism by culture
Doubling time of Tb bacilli
18-24 hours
Cells responsible for containment of Tb bacilli as local pulmonary infiltrates and hilarity adenopathy
Th1 cells
Progression from Tb infection to Tb disease occurs in ___% of affected individuals
10
Key risk factors for Tb (4)
1) Household contact with a newly diagnosed smear (+) case 2) Age less than 5 years 3) HIV infection 4) Immunocompromised state
Size of the infective droplet nucleus of Tb
5 micra
5 stages of pulmonary pathology of Tb
1) Scavenging non activated alveolar macrophages digest tb bacillus 2) (Symbiosis) Macrophage fails to destroy the bacillus undergoing replication destroying the macrophage; other macrophages are attracted leading to development of GRANULOMA 3) Increase in number of tubercle bacilli inhibited by development of CELL-MEDIATED IMMUNITY and DELAYED-TYPE HYPERSENSITIVITY 4a) Enlargement of tubercle and its caseous center with hematogenous spread in weak immunity 4b) Stabilization or regression of tubercle in hosts with strong immunity 5) CASEOUS CENTER LIQUEFACTION, extracellular bacillary growth, cavity formation, and bronchial dissemination
Lung lesion of primary Tb
Ghon focus
Most frequent site of scrofula
Nodes in the ANTERIOR TRIANGLE of the neck
MCC of mortality from Tb in children below 3 years of age
Tb meningitis
T/F Tb men is ALWAYS secondary to a tuberculous process elsewhere in the body
T
Tb of the long bones usually start as
Area of endarteritis in the metaphysis of the long bone
Pott’s disease has a predilection for
Lower thoracic, upper lumbar and lumbosacral vertebrae
Tb of the joints is rare in children; it has a predilection for
Joints of the upper extremities with monoarticular involvement
Initial radiographic picture of primary tb
Parenchymal infiltration accompanied by ipsilateral LN enlargement
LN in this area appear to be the ones most often affected in Tb lymphadenopathy
Right upper paratracheal area
Why the right upper paratracheal LN are most often affected in Tb lymphadenopathy
Lymphatic drainage of the lungs occurs predominantly from left to right
Radiologic finding that clearly differentiates primary from post primary/reactivation tb
Hilar or paratracheal LN enlargement
MC radiographic manifestation of reactivation pTB
Focal or patchy heterogeneous calcification in the apical and posterior segments of the upper lobes and superior segments of the lower lobes
Radiologic hallmark of reactivation TB
Cavities
Phemister triad
1) Juxtaarticular osteoporosis 2) Peripherally located osseous erosions 3) Gradual narrowing of interosseous space
What is the Phemister triad
Characteristic radiologic finding in tuberculous arthritis
Most specific finding in diagnosis of CNS Tb
Basal cistern hyperdensity
MC complication of TB meningitis
Communicating hcp
Vaccine category that may suppress tuberculin reaction
Live virus vaccine
DOH HTP recommends that TST be delayed for ___ after a bout of measles, mumps, chicken pox, or whooping cough
2 months
An induration of ___ is considered a (+) TST
≥10 mm
An induration ≥5mm is considered a positive TST in the presence of
1) History of close contact with a known or suspected infectious case of TB 2) Clinical findings suggestive of Tb 3) CXR suggestive of TB 4) Immunocompromised condition
Clinical manifestations which, when taken together, are most suggestive of childhood Tb disease
History of recent weight loss or failure to gain weight
Spectrum of TB
1) Exposure 2) Infection 3) Disease
Spectrum of TB: Exposed but no signs/symptoms, negative TST CXR sputum AFB and other diagnostics
Exposure or Class I
Spectrum of TB: Only one with signs and symptoms
Disease or Class III
Spectrum of TB: TST may be positive but negative in most children
Infection or Class II
Anti Tb drugs: Bactericidal
H, R, Z (weakly), S
Anti Tb drugs: Bacteriostatic
Ethambutol
Anti Tb drugs: Inhibits nucleic acid synthesis
H, R
Anti Tb drugs: Potent sterilizing activity within macrophages
Z
Anti Tb drugs: Dose
HRZES in order: 10-15mg/kg, 10-20, 20-40, 15-25, 20-40
Anti Tb drugs: Max dose
HRZES in order: 300mg, 600, 2g, 1.2g, 1g
D/C INH if transaminase levels is ___ from normal or with hepatitis
> 3.5x
Adverse reactions to Streptomycin
1) Sterile abscess 2) Auditory function impairment
Algorithm for Preventive Therapy of Childhood TB: TB exposure, less than 5 years old
INH x 3 months
Algorithm for Preventive Therapy of Childhood TB: TB exposure ≥ 5 years old
Mantoux test, if (+) with radiologic findings plus signs and symptoms, treat as TB disease; if (+) with no radiologic findings, signs or symptoms, treat as latent TB infection; if (-) with no BCG scar, give BCG after 2 weeks
After 3 months INH for TB exposure less than 5 years old
Repeat Mantoux test, if (-) with no BCG scar, give BCG after 2 weeks; if (+) with radiologic findings plus signs and symptoms, treat as TB disease; if (+) with no radiologic findings, signs or symptoms, treat as latent TB infection
Treatment for latent TB infection
9-12 months INH including 3 months initially given for exposure
Standard treatment for TB in pregnant women
HRZE
Can a woman breastfeed while treating for TB
Breastfeeding is encouraged because only minimal amounts of the drug are excreted in breastmilk
Treatment for mothers with latent TB infection
INH IMMEDIATELY WITHOUT DELAY
T/F The mother who has current TB disease but has undergone treatment for 2 weeks or more is presumed to be no longer contagious at the time of delivery
T
Management of newborn of mother with TB disease
Give INH for 3 months then TST; if TST (-) D/C INH and give BCG; if TST (+) with no radiographic findings, signs, and symptoms, complete 9 months of INH
Recommended for infants whose mothers have TB disease and has not yet undergone treatment
1) Separation from mother 2) Give INH or rifampicin if INH-resistant for 3 months 3) Do TST, if (+) but CXR (-) complete 9 months of INH or RIF; if (-), repeat after 3 months
Recommended for infants if CXR and TST of mother are negative and has completed treatment
Give BCG and D/C INH
Treatment for congenital TB
2 HRZS, 4-7 HR
