A Case of Simultaneous Bilateral Idiopathic Facial Nerve Paralysis Developing during Treatment of Malignant Lymphoma

Facial nerve paralysis is unilateral in most cases, and cases of bilateral facial nerve paralysis are rare. In particular, simultaneous bilateral facial nerve paralysis is very rare. We encountered a patient with malignant lymphoma who developed bilateral simultaneous facial nerve paralysis during chemotherapy. A 72-year-old man diagnosed as having Hodgkin’s disease was hospitalized during the second course of AVD therapy with suspected febrile neutropenia, 5 days before our first examination. He complained of difficulty in moving his lips, and was referred to our department the following day. Examination at our department revealed scarce facial movements on either side. A head MRI, and blood and cerebrospinal fluid examinations revealed no remarkable findings. Considering that the patient was in an immunocompromised state, we started the patient on steroid therapy (administered for 10 days) two days after our first examination. Even though cerebrospinal fluid examination was performed three times, only a mild increase in cell number and protein level was observed; all other laboratory data were also negative, and we diagnosed the patient as a case of simultaneous bilateral idiopathic facial nerve paralysis. The facial movements improved gradually, with complete recovery achieved at one year four days after our first examination. Bilateral facial nerve palsy is often a symptom of systemic disease. Since various tests to identify the cause were negative in this case, we considered the condition as idiopathic in origin; however, since cerebrospinal fluid examination revealed an increase in both the cell number and protein level, the patient may have had mild viral meningitis. ENoG monitoring may allow evaluation in cases of bilateral paralysis.