Tuberculosis (tb) Part 5

losis (TB) is the number one infections disease killerNew York to Los Angeles). The chest radiograph
worldwide. The World Health Care Organizationshould not be delayed during the first 3 months of
estimates that 2 billion people have latent TB, whilepregnancy if the patient has symptoms.o Treatment
another 3 million people worldwide die each year duefor active TB should be initiated even during the first
to TB.3 months of pregnancy. INH, rifampin, and ethambutol
On average, the isoniazid (INH) resistance rate ismay be used. Pyrazinamide should be used only in
approximately 10% and the rifampin resistance rate iswomen infected with HIV who are suspected of
approximately 1%, with lower numbers in countrieshaving MDR-TB.o In most pregnant women,
with good TB programs and higher numbers in thepreventive treatment should be delayed until 2-3
countries with poor TB programs.months after delivery, even through no harmful
Humans are the only known reservoir foreffects of INH on the fetus have been documented.
Mycobacterium tuberculosis. TB is transmitted byConsider preventive treatment during pregnancy in
airborne droplet nuclei, which may contain fewer thanthe following situations.
10 bacilli. Exposure to TB occurs by sharing common" Pregnant women with a positive tuberculin skin test
airspace with a patient who is infectious. Whenwho are HIV seropositive or who have behavioral
inhaled, droplet nuclei are deposited within therisk factors for HIV infection but decline HIV testing.
terminal airspaces of the lung. Upon encountering the" Pregnant women with a positive tuberculin skin test
bacilli, macrophages ingest and transport the bacteriawho have in close contact with a patient who is
to regional lymph nodes.smear-positive for pulmonary TB.
Special Concerns:" Pregnant women who have had a documented
" Pregnancyo Pregnancy provides an opportunity totuberculin skin test conversion in the past 2 years.o
screen for TB; all pregnant mothers can haveTo reduce the risk of peripartum hepatitis,
tuberculin skin testing performed. If skin testingpreventive treatment should not be given for the
results are positive, a chest radiograph can beintial 2-3 months after delivery. Breastfeeding can be
obtained with lead shielding (the amount of radiationcontinued while on preventive therapy. Whether the
exposure of a single chest radiograph has beenbreastfeed infant should receive pyridoxine is
compared to that incurred on a regular flight fromcontroversial.