Therapeutic bronchoalveolar lavages of either the right or left lung were performed under general anaesthesia and paralysis. From age 2 1/2 to 6 years we used a technique that isolated one lung with the help of a balloon catheter (5-7 Fr, Arrow, Reading, USA) placed into one Figure 2 Long term clinical course and treatments. Lactate dehydrogenase (LDH), height, weight for height (WfH) expressed as the current weight of the child as a percentage of the normal weight for a given height, capillary CO2 pressure, and carcino embryonic antigen, CEA in serum ( Figure. main stem bronchus through the cuffed endotracheal tube (ID 4.0-5.0) and blocked there (see also Figure 3A ). The position and fitting of the catheter was permanently monitored via an Olympus bronchoscope (BFN20, O.D. 1.8 mm), as described in detail [14] . From age 7 onward the size of the main bronchus was sufficient to allow double lumen tube and lavage of one lung, while ventilating the other. Sterile 0.9% NaCl warmed to body temperature was used as lavage fluid. The lavage was done by manual injection and withdrawal of saline from a 50 ml syringe, starting with smaller volumes of 4 ml/kg body weight (used for diagnostic purposes) and increasing to about 11 to 15 ml/kg under continuous control of the correct position and tightness of the balloon. The recovered fluid was collected via a 2-way cock stop into 500 ml bottles to allow judgement of turbidity and to follow the process of lavage [15] . In 2003, at age 5 y, we tried to increase the yield of lipo-proteins recovered from the lungs with the help of perfluorocarbons (PFC) [16, 17] . A total of 100 ml of Perfourodecalin (Pharmpur, Augsburg, Germany) was instilled in 3 aliquots after the 6th, 7th, or 8th 500 ml wash during three consecutive WLL sessions. This approach did neither improve the yield of phospholipids washed out ( Figure 4A , B) nor that of total protein (not shown).