Quick answer
What is tuberculosis?
Tuberculosis (TB) is a bacterial infection usually affecting the lungs — causing persistent cough, weight loss, night sweats, and fever. It spreads through close prolonged contact via cough droplets. Latent TB has no symptoms but can reactivate — treated to prevent active disease. Active TB needs months of antibiotics — usually 6 months combination therapy on the NHS. See a GP if you have cough over 3 weeks with weight loss or night sweats, or if you were born in or travelled to high-TB countries.
Tuberculosis (TB) — still present in the UK
Tuberculosis is infection with Mycobacterium tuberculosis — most often lungs (pulmonary TB) but can affect any organ (extrapulmonary TB).
UK incidence is low compared globally but concentrated in urban areas and migrant communities from high-prevalence countries. Drug-sensitive TB is curable — treatment requires months of antibiotics and public health support.
Pulmonary TB symptoms
Classic triad:
- persistent cough >3 weeks
- weight loss
- night sweats
Also:
- haemoptysis — blood in sputum
- fever, fatigue
- chest pain, breathlessness
Insidious onset — weeks to months — not sudden like pneumonia.
Extrapulmonary TB
| Site | Features |
|---|---|
| Lymph nodes | Painless neck swelling — scrofula |
| Spine (Pott disease) | Back pain, deformity |
| Brain (TB meningitis) | Headache, meningism — emergency |
| Abdominal | Pain, weight loss |
| Genitourinary | Sterile pyuria |
HIV co-infection — atypical presentation, faster progression — see HIV guide.
Latent vs active
Latent TB infection (LTBI):
- positive IGRA/Mantoux blood or skin test
- normal chest X-ray
- no symptoms
- not infectious
- treatment offered if high reactivation risk — immunosuppression, recent conversion
Active TB:
- symptoms + microbiology (culture, PCR) or strong clinical/radiological evidence
- notifiable — contact tracing
- chest X-ray — upper lobe cavitation classic
Diagnosis
- chest X-ray
- sputum — auramine stain, culture, GeneXpert MTB/RIF — rapid resistance detection
- IGRA blood test (interferon-gamma release assay) — latent screening
- HIV test — all TB patients
Treatment
Standard active pulmonary TB ( drug-sensitive):
- 6 months combined antibiotics
- initial 2 months: RIPE — rifampicin, isoniazid, pyrazinamide, ethambutol
- continuation 4 months: rifampicin + isoniazid
Directly Observed Therapy (DOT) — nurse watches doses — ensures completion.
Side effects:
- liver toxicity — monitor LFTs
- orange body fluids — rifampicin
- neuropathy — isoniazid — pyridoxine co-prescribed
MDR-TB — resistant to rifampicin/isoniazid — specialist centre, longer regimens.
Never stop early — breeds resistance.
Prevention
- BCG — selected infants/high-risk
- screening new entrants from high-prevalence countries
- treat latent TB in immunosuppressed before biologics
- ventilation in high-risk settings
When urgent
- massive haemoptysis
- respiratory failure
- TB meningitis suspicion — 999
- MDR-TB — isolation, specialist
TB is slow, treatable, and stigmatised — 3-week cough with weight loss in at-risk groups deserves chest X-ray and sputum, not repeated antibiotics alone.
Common questions
- What are the symptoms of tuberculosis?
- Persistent cough over 3 weeks — sometimes blood-streaked sputum, night sweats, weight loss, loss of appetite, fever, fatigue, chest pain. Extrapulmonary TB affects lymph nodes, spine, brain, kidneys — symptoms vary by site. Many latent cases have no symptoms.
- How do you catch tuberculosis?
- Inhaled droplets from cough or sneeze of person with active pulmonary TB — usually requires prolonged close contact in enclosed spaces — household, prison, some workplaces. Not spread by brief casual contact, plates, or toilet seats. Latent TB is not contagious.
- What is the difference between latent and active TB?
- Latent — bacteria dormant, no symptoms, not infectious, positive skin or blood test. Active — bacteria multiplying, symptoms, infectious — needs treatment and public health contact tracing. Latent can reactivate to active — especially if immunosuppressed.
- How is tuberculosis treated?
- Active pulmonary TB — typically 6 months antibiotics — isoniazid, rifampicin, ethambutol, pyrazinamide combination initially, then continuation phase. Directly observed therapy ensures adherence. Latent TB — shorter regimens (e.g. 3 months isoniazid/rifapentine) for those at high reactivation risk.
- Is there a vaccine for TB?
- BCG vaccine given at birth in areas with high TB rates or to at-risk babies — partial protection against severe childhood TB — not fully protective against adult pulmonary TB. Not part of routine UK schedule in low-incidence areas.
- Can TB come back after treatment?
- Relapse uncommon if full course completed correctly. Reinfection possible in high-exposure settings. Drug-resistant TB harder to treat — emphasises completing standard treatment first time.