December 2002, Volume 32 Number 12 , p 70 - 70
Outline Signs, symptoms, and tests
Treatments and safeguards
Collecting sputum samples
TRUE, THE NUMBER of pulmonary tuberculosis (TB) cases in the United States has been declining, yet more than 16,000 cases were reported in 2000. Teach anyone with suspected or active TB to closely adhere to prescribed therapy and to take precautions to prevent this contagious disease from spreading.
Caused by the bacillus Mycobacterium tuberculosis , TB is spread in droplets when an infected person coughs, sings, speaks, or breathes. Most healthy people who are exposed resist infection, but repeated exposure increases the risk, especially in people whose immune systems are compromised. The bacillus can also enter the lungs and remain dormant for years, causing disease later if the immune system weakens. Someone harboring the dormant bacillus can't spread disease.
Signs, symptoms, and tests
Early signs and symptoms of active TB include persistent cough, fatigue, malaise, weakness, and unexplained weight loss. As the infection progresses, the patient may develop fevers and night sweats and a cough that eventually produces white, frothy sputum. Hemoptysis is a late sign.
The diagnosis of TB is based on a high index of suspicion and results of a skin test, chest X-ray, sputum smear and culture, and possibly a sputum DNA probe.
* The skin test is an intradermal injection of purified protein derivative (PPD) in the forearm. (For the technique, see The Hard Truth about the PPD Skin Test in the June issue of Nursing2001.) Induration (not redness) at the injection site 48 to 72 hours later means the patient has been exposed to TB and developed antibodies, but doesn't necessarily indicate active infection. Anyone who's had a positive response shouldn't be tested again because it always remains positive.
* Chest X-ray ...