What are the signs and symptoms of tuberculosis (TB)?

Signs and Symptoms of Tuberculosis

The most common symptom of pulmonary TB is persistent cough lasting more than 2-3 weeks, with or without sputum production, often accompanied by fever, night sweats, and weight loss. 1

Pulmonary TB Presentation

Primary Respiratory Symptoms

• Persistent cough for ≥2-3 weeks is the hallmark symptom and should trigger TB evaluation 1, 2, 3
• Sputum production may or may not be present; when present, it can be bloody (hemoptysis), though hemoptysis is less common 1, 4
• Chest pain and shortness of breath may occur 2

Constitutional Symptoms (WHO-Endorsed Symptoms)

• Fever - present in the majority of cases 1, 2
• Night sweats - a classic symptom that helps distinguish TB from other respiratory conditions 1, 2
• Weight loss - unintentional and progressive 1, 2
• Fatigue and anorexia - commonly reported 1, 2

The combination of any WHO-endorsed symptom (cough, fever, night sweats, weight loss) is more sensitive for detecting TB than cough alone, with sensitivity of 98% when any one symptom is present 1

Important Clinical Context

Symptom Variability

• TB is not always the leading cause of persistent cough in EU/low-prevalence settings, and cough is not necessarily the most common presenting symptom 1
• Respiratory symptoms overlap significantly with acute respiratory infections and COPD exacerbations 1
• Individuals may have TB without specific signs or symptoms, especially when immunosuppressed 1, 2

Special Population Considerations

HIV-Positive Patients:

• May present with atypical or minimal symptoms 2
• Less specific symptom patterns 2
• Symptom screening sensitivity varies: 91% in those not on antiretroviral therapy vs. 52% in those receiving ART 1

Elderly Patients:

• Less likely to present with fever, sweating, and hemoptysis 2
• More likely to have lower lung involvement rather than classic upper lobe disease 2

Immunocompromised Patients:

• May have minimal or atypical symptoms 2
• The strength of immune response directly affects symptom manifestation 2

Extrapulmonary TB

• Organ-specific signs and symptoms occur depending on the site of infection 1
• Can present with the classic triad of weight loss, fever, and night sweats without pulmonary symptoms 5
• Requires high index of suspicion as presentation is often insidious and nonspecific 5

Critical Risk Factors to Elicit

• History of TB exposure or previous TB diagnosis/treatment 1
• Family history of TB 1
• Conditions causing immunosuppression (HIV, diabetes, malnutrition, smoking, alcohol use) 1, 6
• Immigration from high-prevalence areas 2
• Homelessness or history of incarceration 2

TB in a child is always a sentinel event indicating recent transmission and a likely source case in the family or close contacts 1

Clinical Pitfalls to Avoid

• Do not dismiss persistent cough lasting >2-3 weeks, even if other causes seem more likely 1, 2, 3
• Maintain high suspicion in high-risk populations even with atypical presentations 2
• Consider TB when diagnostic tests for other respiratory infections (including SARS-CoV-2) are negative 3
• Remember that absence of classic symptoms does not exclude TB, particularly in immunosuppressed patients 1, 2