Bacteremia caused by a beta-lactamase producing Haemophilus parainfluenzae strain of a new biotype. A case report

Haemophilus parainfluenzae as a marker of the upper respiratory tract microbiota changes under the influence of preoperative prophylaxis with or without postoperative treatment in patients with lung cancer

Background

Haemophili are representative microbiota of the upper respiratory tract. The aim of this study was to assess the effects of perioperative antimicrobial prophylaxis and/or postoperative treatment on Haemophilus parainfluenzae prevalence, and antimicrobial sensitivity in short-term hospitalized patients with lung cancer who underwent surgery.

Results

Samples were collected from 30 short-term hospitalized patients with lung cancer and from 65 healthy people. The nasal and throat specimens were taken twice from each patient: before (EI, Examination I), on the fourth/fifth day (EII, Examination II) after surgery, and once from healthy people. The isolates identification and antimicrobial susceptibility were detected by routine diagnostic methods. H. parainfluenzae was found in throat specimens of 42/65 (64.6 %) healthy people, while in 19/30 (63.3 %) lung cancer patients in EI (p = 0.6203) and in 13/30 (43.3 %) ones in EII (p = 0.0106). Neither the disease itself nor short-term hospitalization with perioperative prophylaxis alone affected H. parainfluenzae prevalence in EII, while perioperative prophylaxis with postoperative treatment significantly decreased its colonization in EII. The differences in the number of patients colonized by Candida spp. in EI and in EII were observed (p = 0.0082).Totally, 23/58 (39.7 %) of H. parainfluenzae isolates were resistant mainly to beta-lactams; among 11 ampicillin-resistant isolates only 3 were beta-lactamase positive.

Conclusions

The antimicrobial perioperative prophylaxis together with postoperative treatment may disturb the composition of the airways microbiota represented by H. parainfluenzae, in addition to selecting the resistant strains of bacteria and promoting yeasts colonization in lung cancer patients undergoing surgery.

Immune response to Haemophilus parainfluenzae in patients with chronic obstructive lung disease

Haemophilus parainfluenzae is often isolated from the sputa of patients with chronic obstructive lung disease. We have investigated the immune response to this organism in patients with chronic bronchitis (n = 3) and bronchiectasis (n = 10) and in healthy controls (n = 9). Outer membrane proteins (OMPs) of H. parainfluenzae were purified for use in enzyme-linked immunosorbent and immunoblot assays. Whole-cell H. parainfluenzae preparations were used to adsorb antibodies from serum samples, which were subsequently immunoblot assayed to investigate the antibody response to surface-exposed epitopes. Levels of H. parainfluenzae-specific immunoglobulin G (IgG), but not IgA or IgM, were increased in the sera of patients with chronic obstructive lung disease compared to levels in control subjects. The species specificity of the antibody response was confirmed, although a degree of cross-reactivity with H. influenzae antigens was observed. IgA and IgG specific for OMPs of H. parainfluenzae were demonstrated to be present in the sputa and sera of five patients with chronic obstructive lung disease. Variation in the pattern and intensity of antigen recognition was observed among patients and among immunoglobulin classes. OMPs of approximately 36, 22, and 15 kDa were confirmed to possess epitopes exposed on the surface of intact H. parainfluenzae. We have demonstrated the presence of a species-specific systemic immune response to H. parainfluenzae in colonized patients. A specific antibody response was also observed in sputum, and the antigen specificity of these responses in patients with chronic obstructive lung disease was investigated for the first time. The presence of a specific immune response suggests that H. parainfluenzae may have a pathogenic role in patients with chronic obstructive lung disease.