A Patient with Limbic Encephalitis, Ear Perichondritis, and Episcleritis - An Unusual Presentation of Relapsing Polychondritis.

Relapsing polychondritis (RPC) is a rare autoimmune disease that is characterized by recurrent inflammation and destruction of cartilaginous tissues. Limbic encephalitis is a rare central nervous system manifestation of RPC that has been mentioned in case reports. Recognition of this association, and reliable methods of diagnosis, including the utility of neuroimaging modalities such as positron emission tomography/computed tomography (PET/CT) can be useful in the evaluation of this diagnostic challenge. We report a patient with limbic encephalitis associated with RPC, where PET/CT was effectively used in the diagnosis, and monitoring of response to treatment. We also demonstrate that it can be a useful modality in certain situations when brain magnetic resonance imaging cannot be done.