Differential Diagnosis for the 8-year-old Girl
The patient's presentation with lethargy, fever, intermittent cough, headache, and recent travel to rural Ecuador, along with the findings of papilledema, decreased breath sounds, and the results of the lumbar puncture, suggests a complex and potentially severe infection. The differential diagnoses can be categorized as follows:
- Single most likely diagnosis
- Tuberculous Meningitis (TBM): Given the patient's travel history to rural Ecuador, a region with a higher prevalence of tuberculosis, combined with symptoms of chronic infection (intermittent cough, fever, headache for 3 weeks), lethargy, papilledema indicating increased intracranial pressure, and cerebrospinal fluid (CSF) findings (low glucose, high protein, and a lymphocytic predominance), TBM is a strong consideration. The presence of pulmonary findings (decreased breath sounds and crackles) further supports this diagnosis, as tuberculosis can affect both the lungs and the central nervous system.
- Other Likely diagnoses
- Bacterial Meningitis: Although the CSF profile (lymphocytic predominance) is more suggestive of a viral or tuberculous etiology, bacterial meningitis cannot be ruled out without further testing, especially given the acute presentation with fever and lethargy. The presence of neutrophils in the CSF could indicate a bacterial infection, particularly if the patient was in the early stages of the disease.
- Viral Meningitis: The lymphocytic predominance in the CSF is consistent with viral meningitis. However, the severity of the presentation (lethargy, papilledema) and the travel history make this less likely than TBM but still a consideration.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Brain Abscess: Given the patient's symptoms of increased intracranial pressure (papilledema, lethargy) and the history of fever, a brain abscess is a critical diagnosis not to miss. It could be a complication of a bacterial infection, including those acquired during travel.
- Rickettsial Infections: Although less common, rickettsial infections (such as those causing typhus or spotted fever) can present with severe headache, fever, and altered mental status. The travel history to Ecuador, where these diseases can be endemic, makes this a diagnosis that should not be overlooked.
- Rare diagnoses
- Cysticercosis: Given the travel history to a region where cysticercosis is endemic, this parasitic infection could be considered, especially if there are neurological symptoms. However, the acute presentation with meningitis-like symptoms makes this a less likely diagnosis.
- Histoplasmosis: This fungal infection can cause meningitis, particularly in immunocompromised individuals or those exposed to the fungus during travel. The symptoms and CSF findings could be consistent with histoplasmosis, but it would be considered rare in an otherwise healthy child without specific exposure history.