Clinical and molecular epidemiology of haemophilus influenzae causing invasive disease in adult patients.
OBJECTIVE
The epidemiology of invasive Haemophilus influenzae (Hi) has changed since the introduction of the Hi type b (Hib) vaccine. The aim of this study was to analyze the clinical and molecular epidemiology of Hi invasive disease in adults.


METHODS
Clinical data of the 82 patients with Hi invasive infections were analyzed. Antimicrobial susceptibility, serotyping, and genotyping were studied (2008-2013).


RESULTS
Men accounted for 63.4% of patients (whose mean age was 64.3 years). The most frequent comorbidities were immunosuppressive therapy (34.1%), malignancy (31.7%), diabetes, and COPD (both 22%). The 30-day mortality rate was 20.7%. The majority of the strains (84.3%) were nontypeable (NTHi) and serotype f was the most prevalent serotype in the capsulated strains. The highest antimicrobial resistance was for cotrimoxazole (27.1%) and ampicillin (14.3%). Twenty-three isolates (32.9%) had amino acid changes in the PBP3 involved in resistance. Capsulated strains were clonal and belonged to clonal complexes 6 (serotype b), 124 (serotype f), and 18 (serotype e), whereas NTHi were genetically diverse.


CONCLUSIONS
Invasive Hi disease occurred mainly in elderly and those with underlying conditions, and it was associated with a high mortality rate. NTHi were the most common cause of invasive disease and showed high genetic diversity.
Department of Microbiology, Hospital Universitari de Bellvitge, Universitat de Barcelona-IDIBELL, Barcelona, Spain; CIBER de Enfermedades Respiratorias (CIBERes), ISCIII, Madrid, Spain.
Carmen
C
Puig
Department of Infectious Diseases, Hospital Universitari de Bellvitge, Universitat de Barcelona-IDIBELL, Barcelona, Spain; CIBER de Enfermedades Respiratorias (CIBERes), ISCIII, Madrid, Spain.
Imma
I
Grau
Department of Microbiology, Hospital Universitari de Bellvitge, Universitat de Barcelona-IDIBELL, Barcelona, Spain; CIBER de Enfermedades Respiratorias (CIBERes), ISCIII, Madrid, Spain.
Sara
S
Marti
Department of Microbiology, Hospital Universitari de Bellvitge, Universitat de Barcelona-IDIBELL, Barcelona, Spain; CIBER de Enfermedades Respiratorias (CIBERes), ISCIII, Madrid, Spain.
Fe
F
Tubau
Department of Microbiology, Hospital Universitari de Bellvitge, Universitat de Barcelona-IDIBELL, Barcelona, Spain; CIBER de Enfermedades Respiratorias (CIBERes), ISCIII, Madrid, Spain.
Laura
L
Calatayud
Department of Infectious Diseases, Hospital Universitari de Bellvitge, Universitat de Barcelona-IDIBELL, Barcelona, Spain; CIBER de Enfermedades Respiratorias (CIBERes), ISCIII, Madrid, Spain.
Roman
R
Pallares
Department of Microbiology, Hospital Universitari de Bellvitge, Universitat de Barcelona-IDIBELL, Barcelona, Spain; CIBER de Enfermedades Respiratorias (CIBERes), ISCIII, Madrid, Spain.
Josefina
J
Liñares
Department of Microbiology, Hospital Universitari de Bellvitge, Universitat de Barcelona-IDIBELL, Barcelona, Spain; CIBER de Enfermedades Respiratorias (CIBERes), ISCIII, Madrid, Spain.
Carmen
C
Ardanuy
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D015897:Comorbidity; D003920:Diabetes Mellitus / Q000453:epidemiology*; D005260:Female; D005838:Genotype; D006192:Haemophilus Infections / Q000453:epidemiology* / Q000382:microbiology; D006193:Haemophilus influenzae / Q000145:classification / Q000187:drug effects / Q000235:genetics*; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D017720:Molecular Epidemiology; D058889:Molecular Typing / Q000379:methods; D029424:Pulmonary Disease, Chronic Obstructive / Q000453:epidemiology*; D012703:Serotyping / Q000379:methods; D013030:Spain / Q000453:epidemiology; D055815:Young Adult
D000900:Anti-Bacterial Agents