1. Tuberculosis

2. Etiology Mycobacterium tuberculosis Aerobic
Slow-Growing(24-36 hr. Doubling time)
Complex cell wall
Acid fast
Resistant to drying

3. EPIDEMIOLOGY
Susceptibility to infection with M. tuberclosis disease depends on exposure and person's immune system
Without treatment, tuberculosis disease develops in 5% to 10% of immunologically normal adults with tuberculosis infection at some time during their lives
An estimated 8 million new cases of tuberculosis occur each year among adults, and 3 million deaths are attributedto the disease annually.

4. In developing countries, 1
In developing countries, 1.3 million new cases of the disease occur in children younger than 15 years of age, and 450,000 children die
each year of tuberculosis
Most children with tubercolusis infection and disease acquire M. tuberculosis from an adult with tuberculosis.
Transmission:person to person

5. Children with primary pulmonary tuberculosis disease rarely, if ever, infect other children or adults.
Most initially infectious patients become noninfectious within 2 weeks of starting effective treatment, and many become noninfectious within
several days.

6. CLINICAL MANIFESTATIONS
Tuberculosis infection (latent tuberculosis)
Tuberculosis disease(tuberculosis)

7. Primary pulmonary tuberculosis
in older infants and children is usually an asymptomatic infection
positive TST with minimal abnormalities on the chest radiograph, such as an infiltrate with hilar lymphadenopathy or Ghon complex
Malaise, low-grade fever, erythema nodosum,or symptoms resulting from lymph node enlargement
may occur after the development of delayed
hypersensitivity,

8. Progressive primary disease
is characterized by a primary pneumonia that develops shortly after initial infection
Progression of the primary complex to pulmonary
disease or disseminated miliary disease or
progression of CNS granulomas to meningitis occurs most commonly in the first year of life

9. Tuberculous pleural effusion
accompany primary infection, generally represents the immune response to the organisms
Pleurocentesis reveals lymphocytes and an increased protein level
pleural biopsy may be necessary

10. Reactivation pulmonary tuberculosis
Common in adolescents and typical in adults with tuberculosis
usually is confined to apical segments of upper lobes or superior segments of lower lobes.
There is usually little lymphadenopathy and no extrathoracic infection as a result of established hypersensitivity
This is a manifestation of a secondary expansion of infection at a site seeded years previously during primary infection

11. Advanced disease is associated with cavitation and
endobronchial spread of bacilli.
Symptoms include fever, night sweats, malaise, and weight loss.
A productive cough and hemoptysis often herald cavitation and bronchial erosion.

12. Lymphadenopathy is common in primary pulmonary disease
The most common extrathoracic sites of lymphadenitis are the cervical, supraclavicular, and submandibular areas (scrofula)
Enlargement may cause compression of adjacent structures.

13. Miliary tuberculosis
widespread hematogenous dissemination with infection of multiple organs
characterized by fever, general malaise,weight loss, lymphadenopathy, night sweats, and
hepatosplenomegaly
Diffuse bilateral pneumonitis is common, and meningitis may be present
The chest radiograph reveals bilateral miliary infiltrates, showing overwhelming infection

14. The TST may be nonreactive as a result of anergy
Liver or bone marrow biopsy is useful for the dagnosis.

15. Tuberculous meningitis
most commonly occurs in children younger than 5 years old and often within 6 months of primary infection.
Tubercle bacilli that seed the meninges during the primary infection replicate,triggering an inflammatory response.
This condition may have an insidious onset, initially characterized by low-grade fever, headache, and subtle personality change.

16. Progression of the infection results in basilar meningitis with impingement of the cranial nerves and is manifested by meningeal irritation and eventually increased intracranial pressure, deterioration of mental status, and coma.
CT scans show hydrocephalus, edema, periventricular lucencies, and infarctions
CSF analysis reveals increased cell number (50 to 500/mm3 leukocytes), which early in the course of disease may be either lymphocytes or polymorphonuclear leukocytes

17. Glucose is low, and protein is significantly elevated
Acid-fast bacilli are not detected frequently in the CSF by either routine or fluorescent staining procedures.
Although culture is the gold standard for dagnosis, PCR for M. tuberculosis is useful to make this diagnosis.
Treatment regimens for tuberculous meningitis
generally include four antituberculous drugs and corticosteroids.

18. Skeletal tuberculosis
from either hematogenous seeding or direct extension from a caseous lymph node.
Radiographs reveal cortical destruction; biopsy and culture are essential for proper diagnosis
Tuberculosis of the spine, Pott disease, is the most common skeletal site, followed by the hip and the fingers and toes (dactylitis).

19. Other forms Abdominal tuberculosis Tuberculous peritonitis
Urogenital tuberculosis
Tuberculous pericarditis

20. LABORATORY AND IMAGING STUDIES
Tuberculin Skin Test
Only persons at high risk should be offered a
Mantoux test
Culture

21. Induration ≤5 mm
Children in dose contact with known or suspected
contagious cases of tuberculosis disease
Children suspected to have tuberculosis disease
Findings on chest radiograph consistent with active or previously active tuberculosis
Clinical evidence of tuberculosis disease*
Children receiving immunosuppressive therapy or
immunosuppressive conditions, including HIV
infection

22. Induration ≤l O mm
Children at increased risk of disseminated disease
Children <4 years old
Children with other medical conditions, including
Hodgkin disease, lymphoma, diabetes mellitus, ihronl
renal failure, or malnutrition
Children with increased exposure to tuberculosis disease
Children born, or whose parents were born, in high
prevalence regions of the world
Children frequently exposed to adults who are Hiv
infected, homeless, users of illicit drugs, residents of
nursing homes, incarcerated or institutionalized, or
migrant farm workers
Children who travel to high-prevalence region of the
world

23. Induration ≤ 15 mm
Children ≤ 4 years old without any risk factors

24. Diagnostic Imaging
The initial parenchymal inflammation that follows deposition of infected droplet nuclei in the alveoli of the lung usually is not visible radiographically.
A localized, nonspecific infiltrate with an overlying pleural reaction may be seen, however. This lesion usually resolves within 1 to 2 weeks.

25. All lobar segments of the lung are at equal risk of being the focus of the initial infection.
In 25% of cases, two or more lobes of the lungs are involved, although disease usually occurs at only one site.
Spread of infection to regional lymph nodes occurs early.

26. The hallmark of childhood pulmonary tuberculosis is the relatively large size and importance of the hilar lymphadenitis compared with the less significant size of the initial parenchymal focus, together historically referred to as the Ghon complex (with or without calcification of the lymph nodes).

27. Diagnostic Imaging Hilar lymphadenopathy
Partial bronchial obstruction(air trapping, hyperinflation, and lobar emphysema)
lobar pneumonia without impressive hilar lymphadenopathy.
thin-walled primary tuberculous cavity

28. tuberculous spine
usually show collapse and destruction of the vertebral body with narrowing of the involved disc spaces.
Radiographic findings in bone and joint tuberculosis range from mild joint effusions and small lytic lesions to massive destruction of the bone.

29. DIFFERENTIAL DIAGNOSIS
in early disease the symptoms and signs may be nonspecific.
In pulmonary disease, tuberculosis may appear similar to pneumonia, malignancy, and any systemic disease in which generalized lymphadenopathy occurs.
The diagnosis of tuberculosis should be suspected if the TST is positive or if there is history of tuberculosis in a contact.

30. The differential diagnosis of tuberculous lymphadenopathy includes infections caused by:
atypical mycobacteria,
catscratch disease,
fungal infection,
viral or bacterial disease,
toxoplasmosis,
sarcoidosis,
drug reactions,
and malignancy.

31. TREATMENT
For patients with large populations of bacilli, such as adults with cavities or extensive infiltrates, at least two antituberculous drugs must be given
For patients with tuberculosis infection but no disease, the bacterial population is small, and a single drug, such as isoniazid, can be given

32. Isoniazid and rifampin are bactericidal Along with pyrazinamide
Ethambutol, ethionamide, streptomycin,
and cycloserine are bacteriostatic
A 9-month regimen of isoniazid and refampin cures more than 98% of cases of drug-susceptible pulmonary
The addition of pyrazinamide and another drug (ethambutol or an aminoglycoside at the beginning of the regimen reduces the duration of necessary treatment to 6 months.

33. Meningitis, bone/joint:2 mo of isoniazid, rifampin,pyrazinamide, and an aminoglycoside or ethionamide,once a day, followed by 7-10 mo of isoniazid and rifampin, once a day or twice a week (9-12 mo total)

34. Pulmonary and extrapulmonary(except meningitis
and bone joint) :2 mo of isoniazid, rifampin, and pyrazinamide daily, followed by 4 mo of isoniazid and rifampin twice weekly under DOT

35. COMPLICATIONS
Tuberculosis of the spine may result in angulation or gibbus formation that requires surgical correction after the infection is cured
With extrapulmonary tuberculosis, the major problem is often delayed recognition of the cause of disease and delayed