Waterhouse-Friderichsen syndrome is massive, usually bilateral, hemorrhage into the adrenal glands caused by fulminant meningococcemia. more...
Meningococcus is another term for the species Neisseria meningitidis, which is a cause of the type of meningitis which usually underlies this syndrome. This type of meningitis occurs most commonly in children and young adults, and can occur in epidemics. In the United States it is the cause of about 20% of meningitis cases. At one time it was common among military recruits, but administration of the preventive meningococcal vaccine has greatly reduced this number. Freshman college students living in dormitory housing who have not been vaccinated are another risk group.
Routine vaccination against meningococcus is recommended for people who have poor splenic function (who, for example, have had their spleen removed or who have sickle-cell anemia which damages the spleen), or who have certain immune disorders, such as complement deficiency.
It is sometimes said that the hemorrhage in Waterhouse-Friderichsen syndrome causes an acute adrenal insufficiency, but this is inaccurate, since blood cortisol levels are not decreased. The shock, purpura and intravascular clotting are probably the result of an endotoxin mediated immune reaction caused by sepsis.
The syndrome is named for Rupert Waterhouse (1873-1958), an English physician, and Carl Friderichsen (1886-1979), a Danish physician, who wrote papers on the syndrome, which had been previously described.
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