Differential Diagnosis for Chills, No Fever, and URI Symptoms
- Single Most Likely Diagnosis
- Viral upper respiratory infection (URI): This is the most likely diagnosis, as chills and URI symptoms such as cough, sore throat, and runny nose are common presentations of viral infections like the common cold or influenza, even in the absence of fever.
- Other Likely Diagnoses
- Allergic rhinitis: This condition can cause URI symptoms like sneezing, runny nose, and congestion, and may be accompanied by chills, especially if the allergies are severe.
- Sinusitis: An infection or inflammation of the sinuses can cause URI symptoms, facial pain, and chills, even without fever.
- Influenza (early stages): In the initial stages of influenza, patients may experience chills and URI symptoms before the onset of fever.
- Do Not Miss Diagnoses
- Pneumonia: Although less likely without fever, pneumonia can present with chills, cough, and other URI symptoms, especially in vulnerable populations like the elderly or those with compromised immune systems.
- Pulmonary embolism: This is a life-threatening condition that can cause sudden onset of chills, along with respiratory symptoms like cough and shortness of breath, even in the absence of fever.
- Sepsis (early stages): Sepsis, particularly if caused by a viral or atypical bacterial pathogen, might initially present with chills and URI symptoms before progressing to more severe symptoms, including fever.
- Rare Diagnoses
- Tuberculosis (TB): Although rare, TB can cause chronic URI symptoms, including cough and chills, without fever, especially in its early or extrapulmonary forms.
- Histoplasmosis or other fungal infections: These can cause respiratory symptoms, including chills, and might not always be accompanied by fever, especially in immunocompromised patients.
- Connective tissue diseases (e.g., lupus, rheumatoid arthritis): These conditions can have a wide range of symptoms, including URI-like symptoms and chills, due to autoimmune or inflammatory processes.