Cryptococcal Meningitis Misdiagnosed as Leptomeningeal Disease (LMD): A Case Series
Rutu Patel1, Catherine Joseph2, Merry Chen3
1MD Anderson, 2Neuro-Oncology, MD Anderson Cancer Center, 3MD Anderson Cancer Center
Objective:
To highlight the similarities in the clinical and radiographic presentations of leptomeningeal disease (LMD) and cryptococcal meningitis and emphasize the importance of cerebrospinal fluid (CSF) studies to confirm the diagnosis. 
Background:
Cryptococcal meningitis is an opportunistic fungal infection that affects immunocompromised individuals. LMD occurs when cancer has spread to the CSF. The signs and symptoms of both include headaches, nausea, vomiting, seizures, confusion, and focal weakness. Diagnosis can be challenging in immunocompromised patients with advanced cancer given their similar signs and symptoms.  
Design/Methods:
N/A 
Results:

We present two case reports of cryptococcal meningitis, initially reported as LMD on imaging. 

Case 1: A 58-year-old woman with metastatic lung adenocarcinoma presented with new-onset headache and simple partial seizure; she was initially diagnosed with a stroke based on brain MRI findings. One month later, she developed dizziness, vertigo, intractable nausea, vomiting, and diplopia. A repeat MRI showed nodular leptomeningeal and perivascular enhancement concerning for LMD given her cancer history. CSF studies were positive for cryptococcal antigen. She was treated with Amphotericin B and Flucytosine for 2 weeks. Her symptoms improved, and subsequent brain MRI showed improvement in leptomeningeal enhancement.  

Case 2: A 73-year-old woman with multiple myeloma status post stem cell transplant on maintenance Revlimid presented with headache, confusion, neck pain, nausea, and vomiting. She was diagnosed with cryptococcal meningitis based on CSF results. Brain MRI showed abnormal sulcal contrast enhancement supratentorially and infratentorially, reportedly compatible with LMD. Upon re-review, the findings were most likely related to cryptococcal meningitis given LP results. 

Conclusions:
Leptomeningeal enhancement on brain MRI in cancer patients is typically concerning for LMD. However, it is important to rule out alternative causes. We reported two patients who were initially diagnosed with LMD but later found to have cryptococcal meningitis.  
10.1212/WNL.0000000000205671