Acute sensorimotor polyneuropathy as an early sign of polyarteritis nodosa. A case report

We examined a patient aged 31 who had a sudden burning paraesthesia, pain and numbness in the lower legs together with an increased temperature of 39°C. Clinical examination showed asymmetrical sensory polyneuropathy more clearly seen in the lower legs and the left wrist, with high ESR (up to 44 mm/h), leukocytosis, slight anemia and proteinuria. CSF was normal. After three weeks the temperature suddenly increased again up to 39°C and severe flaccid distal tetraparesis was seen more clearly with foot drop in the left lower leg and dense oedema in the left wrist, purple cyanosis and haemorrhagic foci appeared on the skin of the toes, feet, lower legs and left wrist. ESP increased up to 65 mm/h, CK was 200 IU (normal ≤ 190 IU) and hypergammaglobulinaemia developed. An EMG study showed sensorimotor, mainly axonal, polyneuropathy with different degrees of involvement of some nerves and with conduction block in the left ulnar nerve. Muscle biopsy revealed findings of inflammatory vasculitis that resembled polyartheritis nodosa with secondary denervation atrophy and non-specific myositis. The patient was treated with high doses of prednisolone, dexamethasone and cyclophosphamide with plasmapheresis. Motor disturbances and pain decreased and the patient began walking with a stick. However, the necrosis of the toes gradually progressed to dry gangrene and amputations of the toes were carried out three months after the disease began. At that time the patient had the clinical features of multisystem disease with progressive heart, lung, liver and kidney failure. The patient died suddenly of pulmonary artery thrombo-embolism a year after the onset of the disease. An autopsy confirmed the diagnosis of polyarteritis nodosa (PN). Thus, in this patient the asymmetrical sensory polyneuropathy progressed rapidly in symmetrical sensorimotor peripheral polyneuropathy which preceded the clinical multisystem involvement in polyarteritis nodosa.