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•Neoehrlichiamikurensis (NM) is responsible for flu-like illness after tick bites.•Present in eastern France, NM is underdiagnosed.•PCR targeting both Anaplasmaand NM effectively improves NM diagnosis.

La borréliose de Lyme (BL) causée par les bactéries du complexe Borrelia burgdorferi sensu lato est la maladie à transmission vectorielle la plus fréquente en France. Les travailleurs forestiers sont très exposés aux piqûres de tiques et donc particulièrement exposés aux agents pathogènes qu’elles peuvent transmettre. Estimer la séroprévalence dans cette population permet d’apprécier indirectement son niveau d’exposition, la présence d’anticorps chez un travailleur témoignant qu’il a été infecté antérieurement (parfois de nombreuses années plus tôt), avec ou plus souvent sans symptôme.

Tick-borne encephalitis virus (TBEV) is a zoonotic agent causing severe encephalitis. In 2016, in Northeastern France, we faced a TBEV infection increase, leading to a warning from the Regional Health Agency. Here, we report the confirmed TBE cases diagnosed between January 2013 and December 2016, with particular emphasis on the year 2016.

ABSTRACTThe use of matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) for staphylococcal identification is now considered routine in laboratories compared with the conventional phenotypical methods previously used. We verified its microbiological relevance for identifying the main species of coagulase-negative staphylococci (CoNS) by randomly selecting 50 isolates. From 1 January 2007 to 31 August 2008, 12,479 staphylococci were isolated with phenotypic methods, of which 4,594 were identified as Staphylococcus aureusand 7,885 were coagulase negative staphylococci. Using MALDI-TOF MS from 1 January 2011 to 31 August 2012, 14,913 staphylococci were identified, with 5,066 as S. aureusand 9,847 as CoNS. MALDI-TOF MS allowed the identification of approximately 85% of the CoNS strains, whereas only 14% of the CoNS strains were identified to the species level with phenotypic methods because they were often considered contaminants. Furthermore, the use of MALDI-TOF MS revealed the occurrence of recently characterized Staphylococcusspecies, such as S. pettenkoferi, S. condimenti, and S. piscifermentans. Microbiological relevance analysis further revealed that some species displayed a high rate of microbiological significance, i.e., 40% of the S. lugdunensisstrains included in the analysis were associated with infection risk. This retrospective microbiological study confirms the role of MALDI-TOF MS in clinical settings for the identification of staphylococci with clinical consequences. The species distribution reveals the occurrence of the recently identified species S. pettenkoferiand putative virulent species, including S. lugdunensis.

ABSTRACTA large body of evidence has convincingly shown that Toll-like receptors are necessary sensors for infections with pathogens, but their activation was also suggested to generate autoimmunity. During experimental infections, the lack of these sensors or of their signaling molecules should lead to a deficient immune response. We found out that MyD88, the major adaptor of the Toll/interleukin-1 (Toll/IL-1) receptor signaling pathway, can actually act as a negative regulator of B-cell function in some settings. MyD88-deficient mice infected by Borrelia burgdorferideveloped extreme hypergammaglobulinemia compared to wild-type animals, with high levels of immunoglobulin M (IgM) autoantibodies. In vivo, cell transfer experiments and cell blocking assays showed that this phenotype was not linked to the absence of MyD88 in B cells but rather to CD4 T-cell and likely dendritic cell dysfunctions leading to a Th1-to-Th2 cytokine switch. In addition, our results suggest a relative defect in the Ig class switch recombination process, since MyD88 knockout mice developed mostly IgM antibodies. Collectively, these data emphasize the complex role of the Toll/IL-1 receptor pathway in tuning the immune response against infection and avoiding autoimmunity.

A large body of evidence has convincingly shown that Toll-like receptors are necessary sensors for infections with pathogens, but their activation was also suggested to generate autoimmunity. During experimental infections, the lack of these sensors or of their signaling molecules should lead to a deficient immune response. We found out that MyD88, the major adaptor of the Toll/interleukin-1 (Toll/IL-1) receptor signaling pathway, can actually act as a negative regulator of B-cell function in some settings. MyD88-deficient mice infected by Borrelia burgdorferi developed extreme hypergammaglobulinemia compared to wild-type animals, with high levels of immunoglobulin M (IgM) autoantibodies. In vivo, cell transfer experiments and cell blocking assays showed that this phenotype was not linked to the absence of MyD88 in B cells but rather to CD4 T-cell and likely dendritic cell dysfunctions leading to a Th1-to-Th2 cytokine switch. In addition, our results suggest a relative defect in the Ig class switch recombination process, since MyD88 knockout mice developed mostly IgM antibodies. Collectively, these data emphasize the complex role of the Toll/IL-1 receptor pathway in tuning the immune response against infection and avoiding autoimmunity.

The distinction between primary cutaneous B-cell lymphoma and B-cell pseudolymphoma on a histologic basis may be difficult, particularly in some cases of Borrelia burgdorferi-associated lymphoid proliferations. We report two cases of B burgdorferi-associated pseudolymphoma that showed a dense infiltrate with a predominance of large atypical B cells. Because of this misleading histologic feature, a diagnosis of primary cutaneous large B-cell lymphoma was first suspected in both cases. In one case, successive recurrences led to aggressive therapies before the B burgdorferiinfection was recognized. However, a detailed review of histologic and immunohistochemical features was finally suggestive of a B burgdorferi-associated pseudolymphoma in both cases. The etiologic role of B burgdorferiwas confirmed by serology, polymerase chain reaction analysis of B burgdorferiDNA within the lesional skin, and response to antibiotic therapy. Because the distinction between B burgdorferi-associated pseudolymphoma and primary cutaneous B-cell lymphomas may be difficult and true B burgdorferi-associated B-cell lymphomas have been described, we suggest that antibiotic therapy should be considered as a first-line treatment in suspected or confirmed cases of primary cutaneous B-cell lymphoma in regions with endemic B burgdorferiinfection. (J Am Acad Dermatol 2002;47:530-4.)

In France, only one case of tick-borne human granulocytic anaplasmosis has been described in the literature (in 2003). Here, we report 5 new human cases of Anaplasma phagocytophiluminfection from north-eastern France diagnosed in our laboratory in south-eastern France by serology and molecular biology. This increase is directly related to more physician interest in this disease and the implementation of a new PCR tool.

OBJECTIVE To describe a relapse of Whipple disease revealed by isolated limbic encephalitis with no other signs of systemic involvement. DESIGN Case report. SETTING University Hospital of Strasbourg, Strasbourg, France. PATIENT A 41-year-old patient. MAIN OUTCOME MEASURES Cognitive functions and results of cerebrospinal fluid analysis and brain magnetic resonance imaging. RESULTS A 41-year-old patient was hospitalized for headache associated with anterograde amnesia and temporospatial disorientation. Whipple disease with systemic manifestations was diagnosed 4 years previously and insufficiently treated. The neuropsychological evaluation showed impaired episodic memory and executive functions. Analysis of the cerebrospinal fluid showed increased lymphocytes and a positive Tropheryma whipplei polymerase chain reaction result. Cerebral magnetic resonance imaging revealed a typical pattern of limbic encephalitis with an intense signal in the amygdalae and hippocampi. The outcome under antibiotic treatment was marked by partial improvement of the cognitive disorders, disappearance of the positive T whipplei polymerase chain reaction result in cerebrospinal fluid, and a clear decrease of inflammation on brain magnetic resonance imaging. CONCLUSIONS Whipple disease can present as limbic encephalitis. Few cases have been previously described in the literature. Such diagnosis is of importance because of the specific treatment.

ABSTRACTTo evaluate the prevalence of sulfate-reducing bacteria in septic processes, we searched for these bacteria by culture in 100 consecutive abdominal and pleural pus specimens. Twelve isolates were obtained from abdominal samples and were identified by a multiplex PCR as Desulfovibrio piger(formerly Desulfomonas pigra) (seven strains), Desulfovibrio fairfieldensis(four strains), and Desulfovibrio desulfuricans(one strain).

Fifty nymphal Ixodes ricinusticks collected in Alsace, France, identified by morphological criteria and using MALDI-TOF MS, were tested by PCR to detect tick-associated bacteria and protozoan parasites. Seventy percent (35/50) of ticks contained at least one microorganism; 26% (9/35) contained two or more species. Several human pathogens were identified including Borrelia burgdorferis.s. (4%), Borrelia afzelii(2%), Borrelia garinii(2%), Borrelia valaisiana(4%), Borrelia miyamotoi(2%), Rickettsia helvetica(6%) and “Babesia venatorum”(2%). Bartonellaspp. (10%) and a Wolbachiaspp. (8%) were also detected. The most common co-infections involved Anaplasmataceaewith Borreliaspp. (4%), Anaplasmataceaewith Bartonellaspp. (6%) and Anaplasmataceaewith Rickettsiaspp. (6%). Co-infection involving three different groups of bacteria was seen between bacteria of the family Anaplasmataceae, Borreliaspp. and Bartonellaspp. (2%). Results highlight the panel of infectious agents carried by Ixodes ricinus. Co-infection suggests the possibility of transmission of more than one pathogen to human and animals during tick blood feeding.

Broad-range rDNA PCR provides an alternative, cultivation-independent approach for identifying bacterial DNA in reactive and other form of arthritis. The aim of this study was to use broad-range rDNA PCR targeting the 16S rRNA gene in patients with reactive and other forms of arthritis and to screen for the presence of DNA from any given bacterial species in synovial fluid (SF) samples.

Introduction Bacteria and/or their antigens have been implicated in the pathogenesis of reactive arthritis (ReA). Several studies have reported the presence of bacterial antigens and nucleic acids of bacteria other than those specified by diagnostic criteria for ReA in joint specimens from patients with ReA and various arthritides. The present study was conducted to detect any bacterial DNA and identify bacterial species that are present in the synovial tissue of Tunisian patients with reactive arthritis and undifferentiated arthritis (UA) using PCR, cloning and sequencing.Methods We examined synovial tissue samples from 28 patients: six patients with ReA and nine with UA, and a control group consisting of seven patients with rheumatoid arthritis and six with osteoarthritis (OA). Using broad-range bacterial PCR producing a 1,400-base-pair fragment from the 16S rRNA gene, at least 24 clones were sequenced for each synovial tissue sample. To identify the corresponding bacteria, DNA sequences were compared with sequences from the EMBL (European Molecular Biology Laboratory) database.Results Bacterial DNA was detected in 75% of the 28 synovial tissue samples. DNA from 68 various bacterial species were found in ReA and UA samples, whereas DNA from 12 bacteria were detected in control group samples. Most of the bacterial DNAs detected were from skin or intestinal bacteria. DNA from bacteria known to trigger ReA, such as Shigella flexneri and Shigella sonnei, were detected in ReA and UA samples of synovial tissue and not in control samples. DNA from various bacterial species detected in this study have not previously been found in synovial samples.Conclusion This study is the first to use broad-range PCR targeting the full 16S rRNA gene for detection of bacterial DNA in synovial tissue. We detected DNA from a wide spectrum of bacterial species, including those known to be involved in ReA and others not previously associated with ReA or related arthritis. The pathogenic significance of some of these intrasynovial bacterial DNAs remains unclear.