Detection of Legionella anisa in Water from Hospital Dental Chair Units and Molecular Characterization by Whole-Genome Sequencing

This study aims to assess contamination with Legionella spp. in water from dental chair units (DCUs) of a hospital dental ward and to perform its molecular characterization by whole-genome sequencing (WGS). We collect eight water samples (250 mL) from four DCUs (sink and water-syringe). Samples are tested for the presence of Legionella spp. (CFUs/mL) by culturing according to the Nederland Norm (NEN) 6265. Three DCUs are found positive for Legionella anisa, and four isolates are cultured (sink n = 2, water-syringe n = 1; two isolates from the same chair) with 1 × 102 CFU/mL. Whole-genome multi-locus sequence typing (wgMLST) results indicate that all strains belong to the same cluster with two to four allele differences. Classical culture combined with WGS allows the identification of a unique clone of L. anisa in several DCUs in the same hospital dental ward. This may indicate a common contamination source in the dental unit waterlines, which was fixed by replacing the chairs and main pipeline of the unit. Our results reveal tap water contamination in direct contact with patients and the usefulness of WGS to investigate bacterial molecular epidemiology.

Ciprofloxacin-resistant Neisseria meningitidis in Canada: likely imported strains

The prevalence of ciprofloxacin-resistant Neisseria meningitidis in Canada was studied by testing 346 isolates received at the National Microbiology Laboratory during the calendar years 2013 to 2015. Of the 277 individual invasive and 69 noninvasive isolates tested, only 2 serogroup C (MenC) isolates were found to be resistant to ciprofloxacin. Both MenC were typed as sequence type (ST)-4821, a unique clone found mainly in China, thus suggesting both isolates might be from travel-related or imported cases. This prompted us to also examine 6 serogroup A (MenA) isolates in our collection, since MenA is not currently endemic in Canada. Three MenA from 2006 were resistant to ciprofloxacin and they were typed as ST-4789. A ciprofloxacin-resistant MenA strain of ST-4789 was responsible for a meningococcal disease outbreak in Delhi, India, in 2005 to 2006. The 2 MenC and 3 MenA ciprofloxacin-resistant N. meningitidis were from patients residing in British Columbia.

Genetic Structure and Drug Susceptibility Patterns ofMycobacterium tuberculosisComplex Strains Responsible of Human Pulmonary Tuberculosis in the Major Rearing Region in Cameroon

Background. Cameroon this last decade continues to present a low contribution ofM. africanumandM. bovisin human tuberculosis (TB), whileM. boviswas prevalent in cattle but all these pieces of information only concerned West and Center regions.Methods. We carried out the first study in Adamaoua, one of the most rearing regions of Cameroon, on the genetic structure and drug susceptibility of the MTBC strains isolated from newly diagnosed sputum smear-positive patients aged 15 years and above. For that purpose, spoligotyping, a modified 15 standard MIRU/VNTR loci typing, and the proportion method were used.Results. Four hundred and thirty-seven MTBC isolates were analyzed by spoligotyping. Of these, 423 were identified asM. tuberculosis, within the Cameroon family being dominant with 278 (65.7%) isolates; twelve (2.75%) isolates were classified asM. africanumand two asM. bovis. MIRU/VNTR typing of the most prevalent sublineage (SIT 61) suggested that this lineage is not a unique clone as thought earlier but could constitute a group of strains implicated to different pocket of TB transmission. OnlyM. tuberculosissublineages were associated with antituberculosis drug resistance.Conclusion. These results showed the weak contribution ofM. africanumandM. bovisto human active pulmonary tuberculosis in Cameroon even in the rearing region.

Lymphoma Heterogeneity: Three Different Histological Pictures and One Unique Clone

We report a patient who developed up to three different lymphomas with the same clonal IGH rearrangement. She was first diagnosed of splenic zone marginal lymphoma and relapsed for the first time with Hodgkin lymphoma histology and later with diffuse large B-cell lymphoma histology. Subsequent biopsies and analysis of clonally rearranged IGH genes helped to elucidate the clonal relationship between the three histologies and to confirm a common origin from the three tissue histologies. An integrated diagnosis should always be performed in order to achieve the most accurate diagnosis and be able to choose the best therapeutic options for our patients.

Global Dissemination of Vibrio parahaemolyticus Serotype O3:K6 and Its Serovariants

SUMMARY Vibrio parahaemolyticus is recognized as a cause of food-borne gastroenteritis, particularly in the Far East, where raw seafood consumption is high. An unusual increase in admissions of V. parahaemolyticus cases was observed at the Infectious Diseases Hospital in Calcutta, a city in the northeastern part of India, beginning February 1996. Analysis of the strains revealed that a unique serotype, O3:K6, not previously isolated during the surveillance in Calcutta accounted for 50 to 80% of the infections in the following months. After this report, O3:K6 isolates identical to those isolated in Calcutta were reported from food-borne outbreaks and from sporadic cases in Bangladesh, Chile, France, Japan, Korea, Laos, Mozambique, Peru, Russia, Spain, Taiwan, Thailand, and the United States. Other serotypes, such as O4:K68, O1:K25, and O1:KUT (untypeable), that had molecular characteristics identical to that of the O3:K6 serotype were subsequently documented. These serotypes appeared to have diverged from the O3:K6 serotype by alteration of the O:K antigens and were defined as “serovariants” of the O3:K6 isolate. O3:K6 and its serovariants have now spread into Asia, America, Africa, and Europe. This review traces the genesis, virulence features, molecular characteristics, serotype variants, environmental occurrence, and global spread of this unique clone of V. parahaemolyticus.