Tuberculosis (TB) is a disease caused by bacteria called Mycobacterium tuberculosis. The bacteria usually attack the lungs. But TB bacteria can attack any part of the body such as the kidney, spine, and brain. If not treated properly, TB disease can be fatal.
Causes
- Transmission of bacteria Mycobacterium tuberculosis via air on coughing, sneezing
- HIV, Diabetes or other compromised immune conditions.
- Having lived in, travelled to or had visitors from parts of the world where TB is common
- Long use of corticosteroids, chemotherapy, TNF(tumour necrosis factor)
- Too young or too old
- Poor health
- Poor diet
- Alcoholism
- Poor housing with associated overcrowding
- Gastric surgery
- Silicosis
Types of Tuberculosis
Latent TB infection
The bacteria is present in an inactive form in the body and does not produce any symptoms or illness. People with latent TB infection have a positive skin test reaction, but they cannot spread the disease.
Latent TB can develop into active TB
- if treatment is not received for latent TB infection
- if immunity is weak
Active TB infection
The bacteria is present in the body in an active form. The active bacteria begin to multiply in the body and cause active TB disease.
Pulmonary tuberculosis
- Primary TB
The primary focus on the lungs, tonsil or bowel is almost invariably accompanied by caseous lesions in the regional lymph nodes
- Progressive pulmonary TB
Develops directly from a primary lesion or following reactivation of an incompletely healed primary focus
- Post-primary pulmonary TB
Formation of the tuberculous cavity
Extra-pulmonary tuberculosis
- Central nervous system TB
- Gastrointestinal TB
- Genitourinary TB
- Lymph node TB
- Skeletal TB
- Pericardium TB
Symptoms and signs
Symptoms might not begin until many years after being initially exposed to the bacteria.
Pulmonary tuberculosis
- Breathlessness
- Clubbing of the fingers or toes(in advanced stage)
- Fatigue
- Crackles(unusual breath sounds)
- Evening pyrexia
- Anorexia
- Malaise
- Persistent cough with thick phlegm( may be bloody)
- Pleural effusion
- Weight loss
- Sleep sweats
Lymph node TB
- Persistent, painless swelling of the lymph nodes(usually cervical node)
- Caseation
- Liquefaction
- Sinus formation
Skeletal TB
- Vertebral collapse
- Pyarthrosis
- Osteomyelitis
- the weakened bone that may fracture easily
- Cold abscess formation
Gastrointestinal TB
- Tuberculous ulceration of the tongue
- Malabsorption
- Intestinal obstruction
- Ascites
- Diarrhoea
Genitourinary TB
- Burning micturition
- Hematuria
- Nocturia
- Increased frequency of micturition
- Salpingitis
- Tubal abscess
- Painless craggy swelling resulting in sinus formation (epididymis)
Central nervous system
- Headaches
- Stiff neck
- Vomiting
- Disordered consciousness
- Changes in mental state(confusion)
- Blurred vision
- Fits
Pericardium TB
- Pericardial effusion
- Tamponade
- Fibrosis
- Calcification
Investigations
- Mantoux skin test (tuberculin skin test; TST or PPD test)
- Bronchoscopy
- Sputum examination and cultures
- Thoracentesis
- QuantiFERON-TB Gold test
- Chest X-ray
- CT-scan
- MRI-scan
- USG
- Blood and urine test
- Biopsy
- Lumbar puncture
Treatment
Tuberculosis of any type is completely curable with medicines. The only need is early diagnosis and time-bound follow-up.
Complications of TB
- Antibiotic-resistant tuberculosis (TB)
- Multi-drug resistance tuberculosis (MDR-TB)
- Extensive multi-drug resistance tuberculosis (XDR-TB)
- Aspergilloma
- Bloodborne dissemination
- Empyema
- Ischiorectal abscess
- Pleurisy
- Pneumothorax
- Respiratory failure
- Right ventricle failure
- Tuberculous enteritis
- Tuberculous laryngitis
Prevention
- Always cover your mouth when coughing, sneezing or laughing.
- Carefully dispose of any used tissues in a sealed plastic bag.
- Open windows when possible to ensure a good supply of fresh air.
- Stay away from work, school or college until the TB treatment team advises that it is safe to return.
- Bacillus Calmette-Guérin (BCG) vaccination provides protection against TB