g. Cough (which has no specific characteristics).
h. Hemoptysis (blood in the sputum).
i. Pleuritic chest pain (pain in the pleural chest cavity).
6-4.
TYPES OF TESTS
a. Chest X-ray. In almost all cases, a chest x-ray will show the disease. A
single chest x-ray is not usually enough to diagnose tuberculosis. This is because
tuberculosis lesions behind ribs, cardiovascular structures, and the diaphragm will not
show up on a chest x-ray for tuberculosis. Several chest x-rays, therefore, are needed
to establish the activity of the bacilli and to select and determine the appropriate
treatment.
b. Tuberculin Skin Testing. The basis of tuberculin skin tests is that the skin is
hypersensitive to a specific bacterial protein antigen. Administer the antigen and
examine the induration (hardening of the area on which the antigen was placed). A
positive reaction (induration 10 mm or more in diameter) indicates only exposure to
tuberculosis; it does not necessarily mean that the person has tuberculosis. To find out
whether the person has tuberculosis now, use x-ray or bacteriological methods. People
who have a negative tuberculin reaction include the following: those who have never
been infected; those who are in the preallergic early stage of first infection, and,
strangely enough, those with advanced terminal tuberculosis.
(1) Tine test. The tine test uses dried, old tuberculin (OT) on multiple metal
tines (sharp, pointed prongs like a fork) which are in a round, plastic head. When the
tines are pressed against an individual's skin, the antigen is forced between layers of
the skin in the same manner as an injection. This method of testing is safe and
convenient for mass surveys. The site where the test was done should be read
between 48 and 72 hours after the test was performed. What the site looks like
determines whether the test resulted in a positive take, a doubtful take, or a negative
take as noted below:
(a) Positive take--induration but no erythema (abnormal) skin
redness.
(b) Doubtful take--2 mm induration.
(c)
Negative take--less than 2 mm induration.
(2) Mantoux test. This test, used for adult testing, must be used if the tine
test is doubtful or positive. The test requires intradermal injection of antigen 0.1 ml (1
I.U.) of purified protein derivative (PPD). If a fairly high level of susceptibility is
expected, 0.1 ml (0.5 I.U.) of PPD may be used. Read from 48 to 72 hours. Note the
following information:
MD0568
6-4