The authors report a case of a 52-year old female previously followed at the Outpatient Rheumatology Clinic with the diagnosis of Fibromyalgia (FM). Approximately 2 years after this diagnosis, she presents with a 2nd degree burn in a hand, as a result of thermal hypoesthesia. The patient described hipostesia of the distal upper and lower limbs, incontinence of the anal sphincter and chronic diarrhoea with progressive worsening. The electromiography showed sensory-motor axonal polyneuropathy, chronic, moderate to severe. The muscle and nerve biopsy showed deposition of amyloid substance. The search for TTR Met 30 was positive, confirming the diagnosis of familial amyloidotic polyneuropathy. This is the first reported case of familial amyloidotic polyneuropathy as part of the differential diagnosis of fibromyalgia.