Differential Diagnosis
The patient's symptoms have progressed from fever and headache to include neck stiffness, photophobia, haematemesis, haematuria, pallor, and scleral icterus. This progression suggests a severe and potentially life-threatening condition. Here's a categorized differential diagnosis:
Single most likely diagnosis
- Malaria with complications (cerebral malaria and severe anemia): The initial symptoms of fever and headache, followed by the use of malaria medication, suggest that malaria could be the primary diagnosis. The worsening of symptoms, including neck stiffness and photophobia, could indicate cerebral involvement, a known complication of malaria. Haematemesis and haematuria could be due to severe thrombocytopenia or disseminated intravascular coagulation (DIC), both of which can occur in severe malaria. Pallor and scleral icterus suggest severe anemia and jaundice, respectively, which are also consistent with severe malaria.
Other Likely diagnoses
- Viral hemorrhagic fever (e.g., Lassa fever, Ebola): These diseases can present with fever, headache, and progression to hemorrhagic symptoms like haematemesis and haematuria. The presence of neck stiffness and photophobia could indicate meningitis, which can be a complication of some viral hemorrhagic fevers.
- Meningitis (bacterial or viral): The symptoms of neck stiffness, photophobia, and worsening headache are classic for meningitis. However, the presence of haematemesis, haematuria, pallor, and scleral icterus suggests a more complex or severe disease process.
- Sepsis with DIC: Sepsis can cause a wide range of symptoms, including fever, headache, and hemorrhagic manifestations due to DIC. The progression of symptoms and the presence of pallor and scleral icterus could be consistent with septic shock and multi-organ failure.
Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Thrombotic thrombocytopenic purpura (TTP): Although less common, TTP can present with thrombocytopenia, microangiopathic hemolytic anemia (which could explain the pallor and scleral icterus), and can involve neurological symptoms. It's a medical emergency requiring prompt treatment.
- Hemorrhagic stroke: The sudden onset of headache, neck stiffness, and photophobia could indicate a hemorrhagic stroke, especially if there's a history of hypertension or other risk factors. The presence of haematemesis and haematuria might be due to a separate cause but warrants consideration of a catastrophic intracranial event.
Rare diagnoses
- Leptospirosis: This zoonotic infection can cause a wide range of symptoms, including fever, headache, and in severe cases, hemorrhagic manifestations and jaundice (Weil's disease). It's less common but should be considered in individuals with exposure to contaminated water.
- Hantavirus infection: Certain strains of hantavirus can cause hemorrhagic fever with renal syndrome (HFRS) or hantavirus pulmonary syndrome (HPS), both of which can present with severe symptoms including hemorrhage and renal failure. However, these are relatively rare and typically associated with specific geographic exposures.