Download Tuberculosis in Children and Young Adults

Tuberculosis in
Children and
Young Adults
FARHAD SALEHZADEH MD.
2009 ARUMS
Transmission and Pathogenesis
TB
Primary infection •
Reactivated TB •
Progressive post primary TB •
Miliary TB •
Lymphohematogenesis TB •
Evaluation for TB
•
Medical history
•
Physical examination
•
Mantoux tuberculin skin test
•
Chest radiograph
•
Bacteriologic or histologic exam
“Clinical judgement”
Tuberculosis is one of the great imitator.
Common Sites of TB Disease
•
Lungs
•
Pleura
•
Central nervous system
•
Lymphatic system
•
Genitourinary systems
•
Bones and joints
•
Disseminated (miliary TB)
Conditions That Increase the Risk of
Progression to TB Disease
•
•
•
•
•
•
•
•
•
•
HIV infection
Substance abuse
Recent infection
Chest radiograph findings suggestive of previous
Diabetes mellitus
Immunosuppressed
End-stage renal disease
Chronic malabsorption syndromes
Low body weight (10% or more below the ideal)
Systemic Symptoms of TB
•
Fever
•
Chills
•
Night sweats
•
Appetite loss
•
Weight loss
•
Easy fatigability
Extrapulmonary TB
•
In most cases, treat with same regimens
used for pulmonary TB
Bone and Joint TB, Miliary TB,
or TB Meningitis in Children
•
Treat for a minimum of 12 months
TB in Children
WHO estimate of TB in children •
1.3 million annual cases –
450,000 deaths –
15% of TB in low-income countries •
children vs. 6% in United States
Risk of Progression to Disease
Age •
43% in infants (children < 1year) –
25% in children aged one to five years –
15% in adolescents –
10% in adults –
Recent Infection •
Malnutrition •
Immunosuppression, particularly HIV •
Miller, 1963
Childhood TB diagnosed by:
Combination of :
 Contact with infectious adult case
 Symptoms and signs
 Positive tuberculin skin test
 Suspicious CXR
 Bacteriological confirmation
 Serology
Childhood TB
Retrospective study of 43 hospitals using
National TB Data from 1998
2739 cases in children (11.9%) •
1.3% smear-positive, 21.3% smear- –
negative, 15.9% extrapulmonary
Poor outcomes •
45% completed treatment –
17% died –
13% default –
21% unknown –
Harries AD et al.
Int J Tuberc Lung Dis. 2002; 6: 424-31.
•
TB and BCG Vaccination
Efficacy for adult pulmonary TB 0- •
80% in randomized clinical trials
Best efficacy against serious •
childhood disease
64% protection against TB meningitis –
78% protection effect against –
disseminated TB
BCG important for young children, •
inadequate as single strategy
Colditz GA et al. JAMA 1994; 271: 698-702.
TB PEDIATRIC
In older children and adults the distinction between
TB infection and disease is usually clear and often
separated by a period of years before the onset of
reactivation-type disease. A major reason for making
the distinction between infection and disease is because
each is treated differently. Infection is treated
with one medication, whereas disease is treated with at
least three or more anti-TB drugs.
A diagnosis of latent TB infection (LTBI) can be
made solely on clinical grounds and a positive TST
or
INF--releasing assay (IGRA).
The IGRAs
results are unaffected by prior BCG vaccination.
IGRAs are highly
specific and correlate well with known exposure
history.
IGRAs appear to be sensitive, at least in children
over 2 years of age. It is reasonable to hold off on
treatment in a TST, IGRA asymptomatic child
who is over age 2 years and has a normal CXR.
Worldwide the most common symptoms of
pediatric
TB disease are a chronic cough for more than 21
days,
a fever 38°C for 14 days (after common causes such
as malaria and pneumonia have been excluded), and
weight loss or failure to thrive.1 Any child with any of
these symptoms for a shorter duration than described
above and a history of contact to an index case should
have a TST planted and diagnostic workup for TB,