Differential Diagnosis
- Single most likely diagnosis
- Dengue fever: The patient's symptoms, including high fever, severe headache, vomiting, diarrhea, and an erythematous macular rash covering the entire body, are consistent with dengue fever. The patient's recent travel to Southeast Asia, a region where dengue fever is endemic, further supports this diagnosis.
- Other Likely diagnoses
- Chikungunya: Similar to dengue fever, chikungunya is a viral illness that can cause fever, headache, and rash, and is also prevalent in Southeast Asia.
- Typhoid fever: The patient's symptoms, including fever, headache, and rash, could be consistent with typhoid fever, which is common in Southeast Asia.
- Influenza: Although less likely given the patient's travel history and specific symptoms, influenza could still be a consideration, especially given the patient's recent plane travel and airport layovers.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Meningitis: Although the patient does not have nuchal rigidity, meningitis is a potentially life-threatening condition that must be considered in any patient with fever, headache, and altered mental status.
- Septic shock: The patient's hypotension, tachycardia, and diaphoresis suggest septic shock, which could be caused by a variety of bacterial or viral infections.
- Hemorrhagic fever (e.g. Ebola, Lassa fever): Although less likely given the patient's travel history and symptoms, hemorrhagic fever is a potentially deadly condition that must be considered in any patient with fever, headache, and rash.
- Rare diagnoses
- Zika virus: Although less likely given the patient's symptoms and travel history, Zika virus is a rare but potential consideration, especially given the patient's recent travel to Southeast Asia.
- Leptospirosis: This bacterial infection is rare but can cause fever, headache, and rash, and is more common in certain regions of Southeast Asia.
- Rickettsial infections (e.g. scrub typhus): These infections are rare but can cause fever, headache, and rash, and are more common in certain regions of Southeast Asia.