Primary Pulmonary Tuberculosis
lobes affected slightly more than lower
Cavitation is rare
pneumonia is almost always associated with lymphadenopathy—therefore,
lobar pneumonia associated with hilar or mediastinal
adenopathy at any age should strongly suggest TB
unilateral hilar and/or paratracheal, usually right sided, rarely
Differentiates primary from postprimary TB—it does not occur in
Much more common in children
Atelectasis classically affects the anterior segments of the upper
lobes or the medial segment of the RML
effusion as a manifestation of primary TB occurs more often in
adults than children
appropriate treatment, it carries the best prognosis of all patterns
of TB and is the least likely to develop complications
accumulates slowly and painlessly—therefore, patients with TB
are seldom seen with a small amount of pleural fluid
Parenchymal disease will almost never be present with a pleural
effusion although lymphadenopathy may
pleural scarring is rarely tuberculous in origin
Postprimary Tuberculosis (“Reactivation TB”)
always affect the apical or posterior segments of the upper lobes or
the superior segments of the lower lobes—bilateral upper lobe
disease is very common
present as pneumonia
may result: the cavity is usually thin-walled, smooth on the inner
margin with no air-fluid level
may occur—from one
upper lobe to opposite lower or to another lobe
Miliary spread (below)
Bronchostenosis due to fibrosis and stricture: fibrosis may
cause distortion of a bronchus and atelectasis many years after the
initial infection—“middle lobe syndrome”
pulmonary nodule—the tuberculoma—may occur in either primary
or postprimary disease; round or oval lesions with small, discrete
shadows in the immediate vicinity of the lesion—the “satellite”
Formation of a pleural effusion in postprimary TB almost always
means direct spread of the disease into the pleural cavity and
should be regarded as an empyema—this carries a graver
prognosis than the pleural effusion of the primary form
Direct extension into the ribs or sternoclavicular joints is
men, Blacks and pregnant women are susceptible
Fever, chills, night sweats are common
weeks between the time of dissemination and the radiographic
appearance of disease
Considered to be a manifestation of primary TB–although clinical
appearance of miliary TB may not occur for many years after
first visible, they measure about 1 mm in size; they can grow to
2-3mm if left untreated
treated, clearing is rapid—miliary TB seldom, if ever, produces
is an association between TB and silicosis, TB and HIV
may be an association between TB and sarcoid
is no association between TB and bronchogenic carcinoma
matter what form of TB the patient has, it tends to look like 1°
and mediastinal adenopathy are common
Cavitation is less common
is no predilection for the apices
(mycobacterium avium-intracellulare) is more common in HIV than TB
the advent of effective chemotherapy for tuberculosis (TB),
treatment strategies included bed rest, improved nutrition, lung
collapse, surgical excision of diseased lung, and isolation. These
methods reduced the incidence but not the mortality of TB (1). The
first effective drug against TB, para-aminosalicylic acid, was
identified in 1944. In the subsequent four decades, additional
anti-TB agents were introduced that have become the foundation of
therapy: streptomycin sulfate, isoniazid (Laniazid), ethambutol
hydrochloride (Myambutol), rifampin (Rifadin, Rimactane), and
pyrazinamide. At present, with the emergence of drug resistance, a
four-drug initial regimen using directly observed therapy is
recommended as standard care (2,3).
An effective anti-TB regimen must contain multiple drugs to which
the organism is susceptible and must be continued for a sufficient
period of time. The American Thoracic Society and US Centers for
Diseases Control and Prevention have established guidelines for
treatment of TB
- Perform drug-susceptibility studies on all isolates of
- Select drugs and treatment duration on the basis of results of
- Repeat susceptibility testing whenever clinical worsening
occurs or new drug resistance is suspected.
- Never add a single drug to a failing regimen.
- Isolate all patients with suspected or proven active TB until
the disease is excluded or effective therapy has been initiated.
- Initiate directly observed therapy in all cases of active TB.
- Perform HIV testing in all newly diagnosed cases of active TB.
- Monitor patients for adverse drug effects and drug
- Consult a specialist early, especially in cases of multidrug-resistant
(MDR) TB, pregnancy, and HIV infection.
- Promptly report all cases of confirmed active TB, as well as
the patient's HIV status, to the state department of health.
Department of health clinics can provide both consultative and
ongoing care through a team of physicians, nurses, social workers,
and outreach specialists free of charge.
In selecting an effective regimen, physicians should take into
account any coexisting conditions (eg, diabetes, renal disease,
hepatic disease, seizure disorder, alcoholism, substance abuse) and
concurrent medication needs. In a patient with previous episodes of
TB, thorough history taking regarding treatment and
susceptibility-testing results is critical to the assessment of
potential drug resistance. Often, initial treatment is started
before findings of drug-susceptibility studies are available.
Therefore, all regimens should be reviewed when these results have
been obtained (2).
|Typical Drug treatment of
|None; cultures pending
||Do not use pyrazinamide in pregnancy
MDR TB refers to M tuberculosis that is resistant to at least
two drugs, usually isoniazid and rifampin. Although the incidence of
MDR TB in the United States has been declining in the last 5 years,
there has been an increase worldwide. In the United States, MDR TB
has been noted mainly among immigrants from countries with high MDR-TB
rates, HIV-infected patients, the homeless, and injecting drug
users. Healthcare workers were found to be at high risk because of
delays in diagnosis and inadequate respiratory isolation procedures.
The most common cause of emergence of drug resistance is previous
inadequate or incomplete treatment (6,7).
The principles of treatment for MDR TB are similar to those
listed for susceptible organisms. Treatment regimens should contain
multiple bactericidal drugs not previously used and to which the
organism is sensitive. Bacteriostatic drugs can also be used (7,8).
Susceptibility testing allows determination of effective regimens,
Duration of treatment for MDR TB depends on the response. In
general, treatment with at least three effective drugs should be
continued until the culture becomes negative, and then a regimen of
at least two drugs should be continued for 12 to 24 months (2,7,8).
Consultation with an experienced specialist should be considered for
management of all cases of MDR TB.
An earlier report by Goble and associates (9) showed a
treatment-failure rate of 44% and a TB-associated mortality rate of
22% among 171 patients with MDR TB between 1973 and 1983.
Fortunately, a more recent study by Telzak and colleagues (10)
reported better results, with a 96% clinical response rate among 25
HIV-negative patients between 1991 and 1994.
Evaluating response to treatment
The efficacy of a
regimen is determined by the rate of bacteriologic conversion during
therapy and the rate of relapse during or after completion of
therapy. Patients should be closely observed during therapy and for
the first 12 to 24 months after its completion
Monitoring should consist of sputum smears and cultures at
biweekly or monthly intervals until cultures become negative or
therapy is completed. A follow-up chest film is indicated if sputum
smears remain positive after 2 months of therapy or if new symptoms
develop. Chest films at regular intervals are not necessary if there
is bacteriologic improvement, but one should be obtained on
completion of therapy.
In treatment of drug-resistant TB, frequent follow-up with sputum
studies and chest films is indicated. In the case of MDR TB, sputum
smears and cultures should be checked quarterly after conversion, to
monitor for relapse.
A finding on acid-fast smear or culture of the sputum after 5 months
of treatment is considered a treatment failure. Failure can result
from prescription of an inappropriate dosage or inadequate number of
drugs, patient noncompliance, malabsorption, or organism resistance
Occasionally, active TB develops within the first 2 years after
successful completion of therapy. In such cases of relapse, the
organism often has a susceptibility pattern that is similar to that
of the initial infection. The possibility of a new infection with
M tuberculosis should also be considered (2,15).
Role of surgery in active TB
In general, M tuberculosis thrives best in a
high-oxygen-level environment. Surgical techniques in the early 20th
century included artificial pneumothorax, plombage (ie, placing
lucite balls or paraffin in pleural spaces),
and pneumoplasty to
collapse the upper lobes and minimize oxygen availability. Advances
in thoracic surgery led to lobar resection or pneumonectomy in some
With the availability of effective drugs, surgery is rarely
used today. However, in carefully selected patients with MDR TB who
have a poor response or an unfavorable prognosis with use of medical
therapy alone, surgical therapy has had cure rates exceeding 90%
(16). Antibiotic activity should be adequate to permit healing of
the bronchial stump and prevent development of bronchopleural
TB and pregnancy
No increase in morbidity or mortality from TB has been noted
during pregnancy if treatment is adequate (2,17). In the United
States, pyrazinamide is not recommended for use in pregnant women;
however, it has been used outside the United States for MDR TB
during pregnancy. The aminoglycosides and all of the second-line
anti-TB medications except para-aminosalicylic acid should be
avoided during pregnancy (2,17). Breast-feeding is safe during
anti-TB therapy. Consultation with a specialist in TB is strongly
recommended when initiating treatment in pregnant women, especially
those with MDR TB. After initial radiographic imaging, follow-up
x-ray monitoring during pregnancy, with proper shielding, is
recommended only if no clinical improvement is noted.
Dissemination of tuberculosis outside of lungs can lead to the
appearance of a number of uncommon findings with characteristic
- Skeletal Tuberculosis: Tuberculous
osteomyelitis involves mainly the thoracic and lumbar vertebrae
(known as Pott's disease) followed by knee and hip. There is
extensive necrosis and bony destruction with compressed fractures
(with kyphosis) and extension to soft tissues, including psoas
- Genital Tract Tuberculosis: Tuberculous
salpingitis and endometritis result from dissemination of
tuberculosis to the fallopian tube that leads to granulomatous
salpingitis, which can drain into the endometrial cavity and cause
a granulomatous endometritis with irregular menstrual bleeding and
infertility. In the male, tuberculosis involves prostate and
epididymis most often with non-tender induration and infertility.
- Urinary Tract Tuberculosis: A "sterile pyuria"
with WBC's present in urine but a negative routine bacterial
culture may suggest the diagnosis of renal tuberculosis.
Progressive destruction of renal parenchyma occurs if not treated.
Drainage to the ureters can lead to inflammation with ureteral
- CNS Tuberculosis: A meningeal pattern of
spread can occur, and the cerebrospinal fluid typically shows a
high protein, low glucose, and lymphocytosis. The base of the
brain is often involved, so that various cranial nerve signs may
be present. Rarely, a solitary granuloma, or "tuberculoma", may
form and manifest with seizures.
- Gastrointestinal Tuberculosis: This is
uncommon today because routine pasteurization of milk has
eliminated Mycobacterium bovis infections. However, M.
tuberculosis organisms coughed up in sputum may be swallowed into
the GI tract. The classic lesions are circumferential ulcerations
with stricture of the small intestine. There is a predilection for
ileocecal involvement because of the abundant lymphoid tissue and
slower rate of passage of lumenal contents.
- Adrenal Tuberculosis: Spread of tuberculosis
to adrenals is usually bilateral, so that both adrenals are
markedly enlarged. Destruction of cortex leads to Addison's
- Scrofula: Tuberculous lymphadenitis of the
cervical nodes may produce a mass of firm, matted nodes just under
the mandible. There can be chronic draining fistulous tracts to
overlying skin. This complication may appear in children, and
Mycobacterium scrofulaceum may be cultured.
- Cardiac Tuberculosis: The pericardium is the
usual site for tuberculous infection of heart. The result is a
granulomatous pericarditis that can be hemorrhagic. If extensive
and chronic, there can be fibrosis with calcification, leading to
a constrictive pericarditis.
The incidence of extrapulmonary TB is about 10% to 14% of newly
diagnosed cases of TB in non-HIV-infected patients and up to 50% in
HIV-infected patients. Occurrences most commonly are pleural
(26.5%), genitourinary (17.9%), miliary (10.6%), bones or joint
(8.8%), central nervous system (4.7%), abdominal (3.8%), or
The treatment regimen for extrapulmonary TB is similar to that
for pulmonary TB. In selected cases (eg, bone or joint TB,
tuberculous meningitis, children with miliary TB), the recommended
duration of treatment is 12 months. Use of adjunctive methods (eg,
addition of corticosteroids in initial management, surgery) has
proved to be beneficial in decreasing morbidity and mortality
Recent treatment advances
Several established drugs not listed in the tables are being
evaluated as possible second-line agents for TB. These include
isoniazid given in high doses (16 to 20 mg/kg), clarithromycin (Biaxin),
clofazimine (Lamprene), metronidazole (Flagyl, Metric 21, Protostat),
and amoxicillin-clavulanate potassium (Augmentin). Use of
fluoroquinolones has increased in treatment of MDR TB. Although some
fluoroquinolones may be as potent as the first-line drugs, they are
still considered second-line agents (2,3,8).
Studies of alternative therapies are under way, including gene
therapy and immunotherapy with aerosolized interferon-gamma or
Mycobacterium vaccae at initiation of treatment. The benefits of
these approaches are not yet established, but such research gives
hope for future development of more effective treatment strategies.
Management of active TB requires a team approach. All patients
newly diagnosed with TB should be tested for HIV infection.
Currently available anti-TB drug regimens are well tolerated and
highly effective. Directly observed therapy has shown improved
survival and decline in the rate of new cases of active TB. In
suspected or proven drug-resistant TB, the regimen should be
individualized in consultation with a specialist experienced in MDR
TB. Primary care physicians play a pivotal role in reducing
morbidity and emergence of drug resistance through early diagnosis
and prompt initiation of an effective regimen under directly
Mass mini Tb screening result card 1976