Tuberculosis: symptoms, testing and treatment

Tuberculosis is a bacterial infection that commonly affects the lungs and needs prompt medical assessment and a full course of prescribed treatment.

It can also involve lymph nodes, bones, the brain, or other parts of the body. Active tuberculosis can spread through the air when a person with infection in the lungs or throat coughs, speaks, or sings. Latent infection is different: bacteria are present but inactive, and there are no symptoms or spread to others.

A persistent cough, fever, night sweats, reduced appetite, tiredness, and unintentional weight loss can occur with active disease. Cough, fever and swollen glands are common presentations; coughing up blood, night sweats and unintentional weight loss are also very common presentations of tuberculosis. Symptoms can build gradually, and disease outside the lungs may cause symptoms in the affected area.

Seek urgent medical care for coughing up blood, severe breathlessness, confusion, severe headache with neck stiffness, or a marked decline in general condition.

Tuberculosis is caused by Mycobacterium tuberculosis. It spreads mainly after shared indoor air exposure to someone with infectious lung or throat disease; it is not usually spread by sharing dishes, clothing, or a brief touch. Whether exposure leads to infection depends on the setting, duration of contact, ventilation, and individual immune response.

After exposure, some people develop active illness while others develop latent tuberculosis infection. Latent infection can become active later if immune defences are weakened. Active disease may remain in the lungs or affect other organs, which is why new symptoms during or after a relevant exposure should be assessed rather than monitored indefinitely.

Closer or prolonged contact with infectious tuberculosis raises exposure risk. Immune suppression, including HIV infection or medicines that suppress immunity, can make active disease more likely after infection. Crowded or poorly ventilated living or working environments can also increase opportunity for airborne spread.

Clinicians combine your symptoms, exposure history, examination, and tests. These may include a chest X-ray, sputum samples to look for the bacteria, and testing for infection when symptoms are absent. Samples can also help identify which medicines are likely to work. Tell the clinician about previous tuberculosis treatment, pregnancy, other medicines, and immune conditions.

Active tuberculosis is treated with a planned combination of antibiotics chosen by a specialist team. Treatment takes time because the bacteria can be slow-growing, and the exact medicines depend on the site of disease, test results, and previous treatment. Do not stop or change medicines without the treating team: missed doses can make treatment less effective and may allow resistant bacteria to develop.

Take medicines exactly as prescribed and keep follow-up appointments so the team can check recovery and side effects. Share any nausea, rash, vision changes, tingling, jaundice, or new symptoms promptly. Your team can explain any temporary precautions for close contact, work, school, or travel while infectiousness is being assessed.

Without treatment, tuberculosis can damage lung tissue and can spread to other organs. Illness outside the lungs may cause complications specific to the affected site, such as neurological symptoms when the tissues around the brain are involved. Early assessment and ongoing follow-up help clinicians respond to complications and medicine side effects.

Good ventilation, prompt assessment of a persistent cough, and following public-health advice after a close exposure help reduce spread. People diagnosed with latent infection may be offered treatment to reduce the chance that it becomes active. If someone in your household is being assessed, ask the clinical team which contacts should be screened.

Start with a GP or urgent care service if you have concerning symptoms or a known exposure. Infectious-disease, respiratory, or public-health teams may support diagnosis and treatment, particularly for disease outside the lungs, medicine resistance, pregnancy, or immune suppression.