Differential Diagnosis for Flu-like Symptoms
The following differential diagnosis is organized into categories to help guide the thought process:
- Single Most Likely Diagnosis
- Influenza: This is the most likely diagnosis due to the similarity in symptoms such as fever, cough, sore throat, and body aches, which are commonly associated with the flu.
- Other Likely Diagnoses
- Common Cold: Although symptoms can be milder, the common cold can present with similar symptoms such as cough, sore throat, and fatigue.
- Respiratory Syncytial Virus (RSV) Infection: Especially in older adults or young children, RSV can cause flu-like symptoms.
- Coronavirus Infection: Including COVID-19, which can present with a range of symptoms from mild to severe, similar to the flu.
- Mononucleosis: Caused by Epstein-Barr virus, it can present with fever, sore throat, and fatigue, although it typically includes lymphadenopathy and hepatosplenomegaly.
- Do Not Miss Diagnoses
- Pneumonia: Bacterial or viral, which can present with flu-like symptoms but requires prompt antibiotic treatment to prevent severe complications.
- Sepsis: A life-threatening condition that can arise from an infection, presenting with fever, tachycardia, and tachypnea, among other symptoms.
- Meningitis: An infection of the meninges that can present with fever, headache, and stiff neck, requiring immediate medical attention.
- Pulmonary Embolism: Although less common, it can present with sudden onset of symptoms like shortness of breath and chest pain, and is life-threatening if not treated promptly.
- Rare Diagnoses
- Adenovirus Infection: Can cause a range of symptoms including flu-like illness, but is less common.
- Cytomegalovirus (CMV) Infection: Typically affects immunocompromised individuals and can cause a mononucleosis-like syndrome.
- Hantavirus Pulmonary Syndrome: A rare but potentially deadly viral infection that can present with flu-like symptoms before progressing to respiratory failure.
- Lymphoma: Certain types can present with systemic symptoms like fever and fatigue, although this would be an uncommon initial presentation.