Polymer Fume Fever

Polymer fume fever is a self-limiting influenza like illness caused by inhaling fumes from heated fluorinated polymers, chiefly polytetrafluoroethylene. Fumes arise when the polymer is heated to over 300 degrees Celsius.

Exposure. Welding or cutting near coated surfaces, machining and moulding of fluoropolymers, overheating non-stick coatings, and smoking cigarettes contaminated with polymer on the hands.

Epidemiology. Underdiagnosed because the illness is brief and resembles viral infection. Repeated episodes are common in the same worker.

Course. Symptoms start 4 to 8 hours after exposure and resolve in 12 to 48 hours. Tolerance does not develop.

Severe disease. Heavy exposure, for example in confined spaces or house fires with coated cookware, can cause chemical pneumonitis and pulmonary oedema.

Pathophysiology.

Pyrolysis produces ultrafine particles and toxic gases such as perfluoroisobutylene and hydrogen fluoride. These injure the alveolar epithelium and release inflammatory cytokines including interleukin-6 and tumour necrosis factor.

The systemic response explains fever, malaise and leucocytosis. Pulmonary oedema follows from capillary leak in severe cases.

• Fever, chills, myalgia, headache and malaise, with cough, chest tightness and a metallic taste.
• Mild dyspnoea and throat irritation.
• Examination is often normal; mild crackles or wheeze occasionally.

Red flags.

• Worsening dyspnoea, hypoxaemia or frothy sputum after the first day (delayed pulmonary oedema, within about 24 hours).
• Persistent fever beyond 48 hours.

• Exposure history: polymer type, heating, ventilation and cigarette contamination.
• Chest radiograph: usually normal; consider after heavy exposure or any respiratory signs.
• Blood count: leucocytosis, usually neutrophilic, peaking within 12 to 24 hours.
• Oxygen saturation and arterial blood gas when dyspnoeic.
• Investigate for infection when fever persists.

Differential diagnosis. Metal fume fever, viral influenza, organic dust toxic syndrome, hypersensitivity pneumonitis, acute chemical pneumonitis, pneumonia, carbon monoxide poisoning.

• Remove from exposure; rest and fluids. Recovery is spontaneous.
• Paracetamol 1 g orally every 6 hours as needed, maximum 4 g in 24 hours (3 g if under 50 kg, chronic alcohol excess or liver disease), for 1 to 3 days. Reduce in hepatic impairment; extend interval when eGFR is under 30.
• Supplemental oxygen to keep saturation at 94 to 98%.
• Salbutamol 100 microgram metered dose through a spacer, 4 to 10 puffs for bronchospasm, repeated every 20 minutes for the first hour, then every 4 hours as needed. Maximum 10 puffs each dose. Monitor heart rate, potassium and oxygen saturation. Caution in arrhythmia and hyperthyroidism.
• Observe for 24 hours when exposure was heavy or in a confined space, because pulmonary oedema can appear late. Admit for hypoxaemia, abnormal radiograph or respiratory distress; manage pulmonary oedema with oxygen and ventilatory support as needed.
• Corticosteroids have no proven benefit in mild disease.

Monitoring. Observe saturation and respiratory rate; review at 48 hours if discharged.

Referral and escalation. Admit for any respiratory compromise; occupational physician for workplace assessment and removal of contaminated cigarettes and heat sources; notification where required.

Special groups. Pregnancy: treat in hospital if respiratory compromise. Cage birds are very sensitive to fumes and may die first.