Invasive Haemophilus influenzae disease in adults in Taiwan.
OBJECTIVE
Haemophilus influenzae is an important cause of invasive infection in infants and children, but it has been considered an uncommon cause of invasive disease in adults. We conducted a retrospective survey of invasive H. influenzae disease in adults in order to better understand the characteristics of clinical presentation and microbiology.


METHODS
Patients older than 18 years with H. influenzae isolated from normally sterile sites, between July 1999 and June 2002 in a teaching hospital for adult patients were retrospectively analyzed. Data on demographics, clinical presentation, serotype, antibiotic susceptibility, and beta-lactamase production of H. influenzae isolates were analyzed.


RESULTS
Fifteen patients were enrolled. The infectious diagnosis of invasive diseases comprised: pneumonia (5 patients), empyema (2), pelvic inflammatory disease (2), peritonitis (2), periorbital cellulitis with abscess formation (2), endophthalmitis (1) and primary bacteremia (1). Most patients were elderly with underlying illness. Of ten H. influenzae isolates available for analysis, two were serotype b and eight were nontypeable. Beta-lactamase production and ampicillin resistance were found in 6 H. influenzae isolates (5 nontypeable, and 1 type b).


CONCLUSIONS
These data show H. influenzae disease in adults to be rare in Taiwan. Our limited number of cases suggest that nontypeable strains predominate in patients with invasive infection due to H. influenzae. Most patients had respiratory tract infections. Ampicillin resistance was found in more than one-half of H. influenzae isolates, and should be taken into consideration when antibiotics are prescribed on an empirical basis.
Wang
Chien-Chun
CC
Division of Infectious Diseases, Department of Medicine, Taipei Veterans General Hospital, and National Yang-Ming University, Taipei, Taiwan.
Kuo
Han-Yueh
HY
Chiang
Dung-Hung
DH
Tsai
Chen-Chi
CC
Lin
Mei-Lin
ML
Chan
Yu-Jiun
YJ
Yang
Su-Pen
SP
Liu
Cheng-Yi
CY
D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000668:Ampicillin Resistance; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D015373:Bacterial Typing Techniques; D005260:Female; D006192:Haemophilus Infections / Q000453:epidemiology / Q000382:microbiology* / Q000503:physiopathology; D006193:Haemophilus influenzae / Q000145:classification / Q000187:drug effects / Q000201:enzymology / Q000302:isolation & purification*; D006784:Hospitals, Teaching; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D012189:Retrospective Studies; D012703:Serotyping; D013624:Taiwan / Q000453:epidemiology; D001618:beta-Lactamases / Q000096:biosynthesis
D000900:Anti-Bacterial Agents; D001618:beta-Lactamases