PERIOPERATIVE CHANGES OF CELLULAR AND HUMORAL COMPONENTS OF IMMUNITY WITH BRAIN-TUMOR SURGERY

Nosocoomial infections, which are not uncommon in neurosurgical intens ive care medicine, may possibly be favoured by an impairment of immuno logical competence of the patient. In a prospective observational tria l, we investigated several parameters of cellular and humoral immunity in 32 patients before and after resection of an intracranial tumour. We quantified the effects of operative procedure, dexamethasone pretre atment, and tumour type. Dexamethasone alone causes an increase of neu trophilic granulocyte count and monocytes, whereas IgG and eosinophili c granulocytes decrease as well as lymphocytes. CD4+ T lymphocytes (T helper cells) and CD8+ T lymphocytes (T cytotoxic/suppressor cells) we re more severely affected than B lymphocytes. Dexamethasone and operat ion in combination act synergistically on T lymphocytes and IgG, while no synergism is obvious in other clinical test parameters. The skin s ensitivity reaction was depressed accordingly. With intracerebral tumo urs (gliomas WHO grades II to IV), levels of T helper cells and eosino philic granulocytes were lower, and levels of IgM and neutrophilic gra nulocytes were higher than with benign extracerebral neoplasms. Postop erative nosocomial infections of the lower respiratory tract occurred almost exclusively in patients subject to severe depression of T helpe r cells.