Purpose. The objectives of this study were to examine environmental (hydrocarbon degrading) Pseudomonas aeruginosa isolates with Multilocus Sequence Typing (MLST) and to determine their relevant features, such as serotype, virulence genes, biofilm forming ability and hydrocarbon degrading capacity.
Methodology. The diversity of environmental isolates was assessed with an MLST scheme. Investigation of virulence determinants included serotyping, hemolytic activity test and the detection of virulence genes exoS, exoY, exoT, exoU, exoA. Biofilm forming ability was examined in a modified microtiter assay, hydrocarbon degrading capacity was determined with gravimetric methods.
Results. The majority of environmental isolates shared the same MLST profiles with isolates of cystic fibrosis (CF). Virulence patterns and serotypes were slightly connected to the phylogenetic localization, but further clinically important features such as antibiotic resistance were not. At least one of the examined environmental isolates was multidrug-resistant, virulent and had biofilm forming ability such as nosocomial P. aeruginosa and retained its hydrocarbon degradation ability.
Conclusion. The current theses that distinguish isolates originating from different sources are questionable; environmental P. aeruginosa can be a potential risk to public health and cannot be excluded as an external (non-nosocomial) source of infections, especially in patients with CF. Further studies such as pulsed-field gel electrophoresis (PFGE) and the determination of other clinically important virulence factors are needed to confirm these findings.
Bird fancier’s lung (BFL) is a pulmonary disease caused by inhalation of avian proteins. The involvement of the microorganisms of droppings has been assumed in the past and this idea still persists today. Our study aimed to compare by immunoprecipitation assay the detection of antibodies against both droppings and microorganisms in the sera of patients (n=15) and asymptomatic exposed controls (n=18). We found that 14/15 BFL patients had negative serological results for isolated microorganisms of the droppings, only one positive against Enterobacter sakasakii. Serological arguments were in accordance with diagnosis in 87 % of cases by testing à la carte antigens from each bird dropping versus 20 % using the standard antigenic panel. Otherwise, the microorganisms antigens issued from dropping flora were negative in 93 % of cases. Consequently, it’s preferable to use the total extract from the patient’s bird droppings to establish the serodiagnosis of the disease.
One of the crucial determinants for successful administration of lactobacilli to the vaginal niche is the use of appropriate Lactobacillus species. In this cross-sectional study 54 human immunodeficiency virus (HIV)-negative and 76 HIV-positive antiretroviral treatment-naïve women were evaluated for culturable vaginal lactobacilli and their association with genital HIV-1 shedding. Lactobacillus species were identified by 16S rDNA sequencing while cervical and plasma HIV-1 viral load was determined by Abbott real-time PCR. Lactobacilli were isolated in 77.8 % HIV-negative and 73.7 % HIV-positive women. The mean log10 plasma and cervical HIV-1 viral loads (RNA copies ml−1) were 3.73±1.02 and 2.85±0.32 respectively. We observed that presence of L. crispatus, L. gasseri or L. jensenii species was associated with undetectable cervical HIV-1 (P=0.046) and reduced genital HIV-1 shedding (P=0.048) compared to other species. Our findings endorse using Lactobacillus-based strategies to aid the prevention of HIV-1 transmission among Indian women, however confirmation by future prospective studies is indeed warranted.