Patients often complain of diplopia, but rarely have complete ophthalmoplegia. There is usually limb weakness as well. Tensilon and EMG testing were not compatible with this diagnosis. Carcinomatous meningitis may present with multiple cranial nerve involvement. As this patient had no lymphadenopathy, no white blood cells, and a normal protein in the initial spinal fluid, this diagnosis was unlikely.
Sarcoidosis can cause bilateral facial weakness.
With the rapid onset of the cranial nerves involved, CXR not showing lymphadenopathy, a normal spinal fluid, and normal ACE level, this was unlikely. Lyme disease also can cause bilateral facial weakness. She had not been in an endemic area , had an initial normal spinal fluid, and negative Lyme titers. This diagnosis was unlikely. Acute intermittent porphyria can be confused with Guillain-Barre syndrome as it tends to cause a motor neuropathy.