3 EPIDEMIOLOGYSusceptibility to infection with M. tuberclosis disease depends on exposure and person's immune systemWithout treatment, tuberculosis disease develops in 5% to 10% of immunologically normal adults with tuberculosis infection at some time during their livesAn 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 dieeach year of tuberculosisMost 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 withinseveral days.
7 Primary pulmonary tuberculosis in older infants and children is usually an asymptomatic infectionpositive TST with minimal abnormalities on the chest radiograph, such as an infiltrate with hilar lymphadenopathy or Ghon complexMalaise, low-grade fever, erythema nodosum,or symptoms resulting from lymph node enlargementmay occur after the development of delayedhypersensitivity,
8 Progressive primary disease is characterized by a primary pneumonia that develops shortly after initial infectionProgression of the primary complex to pulmonarydisease or disseminated miliary disease orprogression 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 organismsPleurocentesis reveals lymphocytes and an increased protein levelpleural biopsy may be necessary
10 Reactivation pulmonary tuberculosis Common in adolescents and typical in adults with tuberculosisusually 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 hypersensitivityThis 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 tuberculosiswidespread hematogenous dissemination with infection of multiple organscharacterized by fever, general malaise,weight loss, lymphadenopathy, night sweats, andhepatosplenomegalyDiffuse bilateral pneumonitis is common, and meningitis may be presentThe 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 infarctionsCSF 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 meningitisgenerally 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 diagnosisTuberculosis 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 tuberculosisTuberculous pericarditis
20 LABORATORY AND IMAGING STUDIES Tuberculin Skin TestOnly persons at high risk should be offered aMantoux testCulture
21 Induration ≤5 mmChildren in dose contact with known or suspectedcontagious cases of tuberculosis diseaseChildren suspected to have tuberculosis diseaseFindings on chest radiograph consistent with active or previously active tuberculosisClinical evidence of tuberculosis disease*Children receiving immunosuppressive therapy orimmunosuppressive conditions, including HIVinfection
22 Induration ≤l O mmChildren at increased risk of disseminated diseaseChildren <4 years oldChildren with other medical conditions, includingHodgkin disease, lymphoma, diabetes mellitus, ihronlrenal failure, or malnutritionChildren with increased exposure to tuberculosis diseaseChildren born, or whose parents were born, in highprevalence regions of the worldChildren frequently exposed to adults who are Hivinfected, homeless, users of illicit drugs, residents ofnursing homes, incarcerated or institutionalized, ormigrant farm workersChildren who travel to high-prevalence region of theworld
23 Induration ≤ 15 mmChildren ≤ 4 years old without any risk factors
24 Diagnostic ImagingThe 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).
28 tuberculous spineusually 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 TREATMENTFor patients with large populations of bacilli, such as adults with cavities or extensive infiltrates, at least two antituberculous drugs must be givenFor 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 bacteriostaticA 9-month regimen of isoniazid and refampin cures more than 98% of cases of drug-susceptible pulmonaryThe 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 COMPLICATIONSTuberculosis of the spine may result in angulation or gibbus formation that requires surgical correction after the infection is curedWith extrapulmonary tuberculosis, the major problem is often delayed recognition of the cause of disease and delayed