Differential Diagnosis
- Single most likely diagnosis
- Influenza: The patient's symptoms, including a non-productive cough, sore throat, laryngitis, severe nasal congestion, conjunctivitis, high fever, and diarrhea, are consistent with a viral respiratory infection. The recent travel to northern Vietnam and the sudden onset of symptoms also support this diagnosis.
- Other Likely diagnoses
- Common cold: Although the symptoms are more severe, the common cold is a possibility, especially given the productive cough and nasal congestion.
- Respiratory syncytial virus (RSV) infection: RSV can cause severe respiratory symptoms, including cough, sore throat, and conjunctivitis, especially in adults who have been exposed to the virus while traveling.
- Adenovirus infection: Adenovirus can cause a range of symptoms, including respiratory symptoms, conjunctivitis, and fever, which are consistent with the patient's presentation.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- SARS-CoV-2 (COVID-19): Although the patient has recently traveled to northern Vietnam, COVID-19 is still a possibility, especially given the respiratory symptoms and fever.
- Avian influenza (H5N1 or H7N9): The patient's recent travel to northern Vietnam, a region with reported cases of avian influenza, and the severity of symptoms, including high fever and respiratory symptoms, make this a "do not miss" diagnosis.
- Meningococcal infection: Although less likely, meningococcal infection can present with fever, sore throat, and conjunctivitis, and can be deadly if not promptly treated.
- Rare diagnoses
- Hantavirus infection: The patient's recent travel to northern Vietnam and the symptoms of fever, cough, and diarrhea could be consistent with hantavirus infection, although this is a rare diagnosis.
- Leptospirosis: The patient's symptoms, including fever, cough, and diarrhea, could be consistent with leptospirosis, although this is a rare diagnosis and would require exposure to contaminated water or soil.