Prevalence of H.influenzae biotypes and their clinical significance in a University Hospital.
OBJECTIVE
Hemophilus influenzae is an important pathogen that is responsible for invasive and non-invasive infections in both children and adults. This study aims to assess the relationship of biotypes to the sites of infection, serotypes, antimicrobial susceptibility, beta-lactamase production and age.


METHODS
A total of 200 isolates of H.influenzae were obtained from clinical specimens over a period of 12 months from January 2001 through to January 2002 from King Abdul-Aziz University Hospital, Riyadh, Kingdom of Saudi Arabia.


RESULTS
Most of the strains were non-typable and were isolated from patients with non-invasive infections. The typable isolates from invasive infections mostly serotype b were isolated from blood, cerebrospinal fluid and hip joint aspirate. Biotype II accounted for 37% of the isolates followed by biotypes III and I (29.5% and 23%). The remaining 10.5% were made up of biotypes IV, V, VI and VII. A significantly high resistance to cotrimoxazole (33.5%) and ampicillin (19%) was observed. Two point five percent of the isolates were resistant to chloramphenicol. All the isolates resistant to ampicillin were beta-lactamase producers and susceptible to cefuroxime, ceftriaxone, ciprofloxacin and rifampicin.


CONCLUSIONS
This study revealed that biotypes II and III are the predominant biotypes of H.influenzae found in non-invasive infections. There is an apparent relationship between biotype and site of infection which could be useful as an epidemiological marker.
Begum
Nurum N
NN
Department of Pathology/Microbiology, King Saud University, College of Medicine, Riyadh, Kingdom of Saudi Arabia. nbijom@ksu.edu.sa
Al-Khattaf
Abdul-Aziz S
AA
Kambal
Abdelmageed M
AM
Yeboah
Edward A
EA
D000293:Adolescent; D000328:Adult; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002648:Child; D002675:Child, Preschool; D024881:Drug Resistance, Bacterial; D005260:Female; D006192:Haemophilus Infections / Q000188:drug therapy / Q000453:epidemiology; D006193:Haemophilus influenzae / Q000187:drug effects* / Q000201:enzymology / Q000302:isolation & purification*; D006785:Hospitals, University; D006801:Humans; D007223:Infant; D008297:Male; D008826:Microbial Sensitivity Tests; D012494:Sampling Studies; D012529:Saudi Arabia / Q000453:epidemiology; D016036:Seroepidemiologic Studies; D001618:beta-Lactamases / Q000378:metabolism*
D000900:Anti-Bacterial Agents; D001618:beta-Lactamases