INVASIVE HAEMOPHILUS-INFLUENZAE INFECTIONS IN OLDER CHILDREN AND ADULTS IN SEATTLE

We recently saw two unusual manifestations of Haemophilus influenzae i nfection in adults in the Seattle area: fulminant sepsis in an otherwi se-healthy man and three episodes of bacteremia in a woman with chroni c liver disease. We retrospectively identified 79 bacteremic and 40 no n-bacteremic cases of invasive H. influenzae infection developing in p atients greater-than-or-equal-to 9 years of age between 1 January 1980 and 31 December 1990. The most common clinical presentations among pa tients with bacteremia included pneumonia (52%), septicemia (27%), men ingitis (8%), gynecologic infection (5%), and epiglottitis (5%). Under lying illnesses were common in these patients, and overall mortality w as 35.5%. Factors associated with mortality included underlying neurol ogical disease, polymicrobial bacteremia, and advanced age. The clinic al presentations of the 40 patients without bacteremia included soft-t issue abscesses (45%), lung abscesses (18%), peritonitis (13%), mening itis (8%), gynecologic infection (8%), epididymitis (5%), mastoiditis (3%), and osteomyelitis (3%). Thus H. influenzae disease has a variety of presentations and is associated with significant mortality in olde r children and adults. Further study is required to determine whether widespread administration of H. influenzae type b conjugate vaccine to infants will alter the development of subsequent disease in later lif e.