Schistz, P.O. (Paediatric Department TG, Rigshospitalet, Copenhagen, Denmark). Systemic and mucosal immunity and non specific defense mechanisms in cystic fibrosis patients. Acta Paediatr Scand 1982; suppl 301: 55-62. -A review is given of the different immunological defense mechanisms in cystic fibrosis that may explain the increased susceptibility to pulmonary infections in these patients. It is concluded that no specific primary defect has been demonstrated so far.