An 18-year old girl developed acute fulminating meningococcaemia with meningitis, coma, shock, coagulation disorders and extensive purpura. Measurement of intracranial pressure showed severe intracranial hypertension. After medical treatment of shock and intracranial hypertension had failed, external drainage of the cerebrospinal fluid was performed in the lumbar region, using a 16 G silicone catheter. This controlled the intracranial hypertension; also the state of shock regressed and the patient became fully conscious. The lumbar drainage was maintained for 12 days during which 3180 ml of blood-stained cerebrospinal fluid were evacuated. The fluid was sterilized by antibiotics as early as the 1st day of the disease, but it remained positive for bacterial antigen up to the 9th day. Cure was obtained without neurological sequelae, thanks to the lumber drainage which controlled intracranial hypertension and removed large amounts of microbial toxins.