• granulocyte-macrophage colony stimulating factor
• pulmonary alveolar proteinosis

Treatment with granulocyte-macrophage colony stimulating factor (GM-CSF) has been shown to benefit a subset of patients with adult pulmonary alveolar proteinosis (PAP). A 47 year old woman with PAP, confirmed by lung biopsy, and severe physiological and symptomatic disturbances was not improved by repeated unilateral whole lung lavages. Six months after the last lavage we started treatment with daily subcutaneous GM-CSF in increasing doses beginning at 3 μg/kg. When a daily dose of 6 μg/kg was reached a haematological response was detected and dose escalation ceased. After 4 weeks at this dose the patient began to improve. By week 11 at a dose of 6 μg/kg/day the treatment was stopped and after a further 3 weeks without treatment she attained maximal clinical, radiological, and physiological improvement (from arterial oxygen tension (Pao₂) 6.1 kPa, alveolar–arterial oxygen gradient ((A–a)o₂) 8.2 kPa, total lung capacity (TLC) 63.3%, and carbon monoxide transfer factor (Tlco) 58.7% at diagnosis to 10.9 kPa, 2.6 kPa, 99%, and 101.1%, respectively). At that point, as the haematological parameters were normal, we decided empirically to restart treatment at a maintenance dose of 3 μg/kg/day twice a week to avoid relapse. Five months later, with no evidence of clinical deterioration or haematological response, treatment was stopped and after a further 18 months the patient remains symptom free.

The successful remission of our patient, the seven published cases of GM-CSF in the treatment of PAP,^1–3 and the low incidence of side effects compared with the whole lung lavage technique prompt us to recommend GM-CSF as a first line treatment option in these patients.