References:
- Global Infectious Diseases and Epidemiology Online Network: Infectious Diseases of the Philippines, 2013 eBook Edition, ISBN 978-1-61755-582-4, by Stephen Berger. Accessed here.
Also Read
| Agent | BACTERIUM. Actinomycetes, Mycobacterium tuberculosis An aerobic acid-fast bacillus |
| Reservoir | Human Cattle |
| Vector | None |
| Vehicle | Air Dairy products |
| Incubation Period | 4 to 12 weeks (primary infection) |
| Diagnostic Tests | Microscopy Culture Nucleic acid amplification Inform laboratory when this diagnosis is suspected |
| Typical Adult Therapy | Respiratory isolation. Typical pulmonary infection is treated with 6 months of Isoniazid, Rifampin, Pyrazinamide, and Ethambutol. |
| Typical Pediatric Therapy | As for adult |
| Vaccines | BCG |
| Clinical Hints | Cough, “night sweats” and weight loss; often presents as prolonged fever (FUO) or infection of bone, meninges, kidneys or other organs; most infections represent reactivation of old foci in lungs, brain, bone, kidneys etc. |
| Synonyms | Consumption, Mycobacterium africanum, Mycobacterium bovis, Mycobacterium caprae, Mycobacterium orygis, Mycobacterium tuberculosis, Oryx bacillus, Phthisis, TB, TB meningitis, Tuberculose, Tuberculose miliar, Tuberculosi, Tuberculous meningitis, Tuberkulose, White plague |
WHO Case Definition for Surveillance
- Pulmonary tuberculosis, sputum smear positive (PTB+)
- Tuberculosis in a patient with at least two initial sputum smear examinations (direct smear microscopy) positive for Acid-Fast Bacilli (AFB), or
- Tuberculosis in a patient with one sputum examination positive for acid fast bacilli and radiographic abnormalities consistent with active pulmonary tuberculosis as determined by the treating medical officer, or
- Tuberculosis in a patient with one sputum specimen positive for acid-fast bacilli and at least one sputum that is culture positive for acid-fast bacilli.
- Pulmonary tuberculosis, sputum smear negative (PTB-)
- Tuberculosis in a patient with symptoms suggestive of tuberculosis and having one of the following:
- Three sputum specimens negative for acid-fast bacilli
- Radiographic abnormalities consistent with pulmonary tuberculosis and a lack of clinical response to one week of a broad-spectrum antibiotic
- Decision by a physician to treat with a full curative course of antituberculous chemotherapy
- Pulmonary tuberculosis, sputum smear negative, culture positive
- Tuberculosis in a patient with symptoms suggestive of tuberculosis and having sputum smear negative for acid-fast bacilli and at least one sputum that is culture positive for M. tuberculosis complex
- Extra-pulmonary tuberculosis
- Tuberculosis of organs other than lungs: pleura, lymph nodes, abdomen, genito-urinary tract, skin, joints and bones, tuberculous meningitis, etc.
- Diagnosis should be based on one culture positive specimen from an extra-pulmonary site, or histological or strong clinical evidence consistent with active extra-pulmonary tuberculosis, followed by a decision by a medical officer to treat with a full course of anti-tuberculous therapy.
- Any patient diagnosed with both pulmonary and extra-pulmonary tuberculosis should be classified as a case of pulmonary tuberculosis
The clinical features of tuberculosis are protean, and largely determined by the site of infection and clinical substrate.
- Most infections represent reactivation of a dormant focus in a lung, with resultant chronic fever, weight loss, nocturnal diaphoresis, productive cough and typical roentgenographic findings.
- Reactivation of an extrapulmonary focus (kidney, bone, central nervous system, skin, gastrointestinal and hepatobiliary system, eyes, skeletal muscle, reproductive tract, breast, etc.) will result in signs referable to the infected organ.
- The extent and severity of disease are influenced by patient age, nutrition, immune function, and many other factors which are beyond the scope of this module.
- Nocardiosis may mimic tuberculosis, particularly in the setting of HIV infection.
- The appearance of a military infiltrates in tropical pulmonary eosinophilia or Chlamydophila pneumoniae infection may suggest a diagnosis of tuberculosis.
- Spinal histoplasmosis may mimic tuberculosis spondylodiscitis; and gastrointestinal histoplasmosis may mimic abdominal tuberculosis.
- The clinical features of melioidosis are similar to those of tuberculosis: prolonged fever, weight loss, latency with reactivation, upper-lobe infiltrates, etc.
- Tularemia and leprosy may manifest as lymphadenopathy mimicking tuberculosis.