Facial Paralysis as Initial Manifestation of Light-chain Amyloidosis

Light-chain (AL) amyloidosis is a systemic disease capable of damaging virtually all body tissues. Neurologic involvement is commonly manifested by dysautonomia and peripheral nervous system affection. However, from 1970 to 2018, only 12 cases of cranial nerve injury associated with AL amyloidosis were identified. Eight months before hospital admission, a previously healthy 61-year-old man complained to his general practitioner of episodes of lipotimia while walking and, three months later, he developed a left facial nerve paralysis assumed, at that time, to be idiopathic. After two months, he started complaining of dyspnea and lower limb edema. Physical examination at admission revealed hypotension, exuberant peripheral edema, jugular venous distention, periorbital purpura and left peripheral facial paralysis. He had elevated troponin and brain natriuretic peptide, mild proteinuria and a monoclonal gammopathy IgG/lambda. Bone marrow biopsy revealed 20% plasmocytes and cardiac ultrasound showed diffuse hypokinesia and restrictive filling pattern. AL amyloidosis with major cardiac involvement was considered and a rectal biopsy revealed amyloid protein. Chemotherapy protocol to AL amyloidosis was initiated but cardiac disease progressed leading to death. Persistent facial nerve paralysis should be considered as a rare initial manifestation of AL amyloidosis allowing an earlier diagnosis.