Association between megakaryocyte abnormalities on bone marrow smear and response to thrombopoietin receptor agonists in adult patients with primary immune thrombocytopenia.

Impaired platelet production is a mechanism of immune thrombocytopenia (ITP). Morphological abnormalities of megakaryocytes (MKs) are sometimes observed in this disease. Two studies have suggested an association between MK abnormalities and response to corticosteroids in primary ITP, but none have investigated this association for thrombopoietin-receptor agonists (TPO-RAs). This was the aim of this study. The source of population was the French CARMEN registry with prospective follow-up of adult patients with incident ITP. We included patients with primary ITP, treated by TPO-RA and with a bone marrow smear before initiating TPO-RA. MK abnormalities were categorized by the presence of dysplasia and by the stage of maturation. Among 451 patients screened, 38 were included in the analysis. There was no difference in the median percentage of dysplastic MKs between responders to TPO-RA (4.0%, 95% confidence interval - CI: 2.3-6.4) and non-responders (4.5%, 95% CI: 0.7-7.1). There was a slightly higher proportion of granular MKs (4.5%, 95% CI: 3-6) and basophilic MKs (30.1%, 95% CI: 21.9-39.1) in non-responders compared to responders (granular: 2.0%, 95% CI: 0-4.1; basophilic: 21.3%, 95% CI: 11.4-40.7). In conclusion, MK abnormalities were not associated with response achievement in ITP patients treated with TPO-RA in this series of 38 patients.

Fatal septic shock caused by Capnocytophaga canimorsus diagnosed by 16S rRNA gene sequencing.

Introduction: Capnocytophaga canimorsus is a commensal bacterium found in the saliva of dogs and cats. In most cases C. canimorsus causes local infection resulting from bite-wounds, scratches or licks but severe forms can occur. The following case describes a severe and rapidly fatal sepsis and disseminated intravascular coagulation with no evidence of bite in a patient without obvious cause of immunosuppression, diagnosed by polymerase chain reaction and 16S rRNA gene sequencing. Case report: Herein we present a rare case of a 39-year-old man who was taken care of by the emergency medical service for faintness, fever and chills associated with generalized mottling. Despite critical care management and broad-spectrum antibiotherapy, the patient presented an irrepressible shock with disseminated intravascular coagulation and multiple organ failure. He died during the night. The initial etiological assessment was negative but rod-shaped inclusions could be observed in his blood. A pan-bacterial polymerase chain reaction targeting part of the gene encoding 16S ribosomal ribonucleic acid (rRNA) was carried out directly on blood cultures; the sequencing identified Capnocytophaga canimorsus. Conclusions: This observation illustrates the potential severity of C. canimorsus infection even in a patient without neither obvious causes of immunosuppression nor evidence of bite. The presence of intracellular bacillary forms on the blood smear is an important information which should lead to performing a polymerase chain reaction and 16S rRNA gene sequencing.

Outbreak of Human Metapneumovirus in a Nursing Home: A Clinical Perspective.

OBJECTIVES: To describe a human metapneumovirus (hMPV) outbreak occurring in a nursing home for older adults and to identify the risk factors associated with the clinical infection. DESIGN: A retrospective, case-controlled study. SETTING AND PARTICIPANTS: A French nursing home for older adults between December 27, 2014 and January 20, 2015. Probable cases were residents presenting at least 1 respiratory symptom or 1 constitutional symptom. Confirmed cases identified in the same way as probable cases but with a positive RT-PCR test for hMPV. Controls were residents with no symptoms of respiratory infection. MEASURES: Identification of hMPV was realized on nasal swab samples by RT-PCR. RESULTS: Seventy-eight older people were resident at the time of the outbreak. Three of the 4 tested were positive for hMPV by RT-PCR and negative for 13 other viruses or bacteria. All probable infected residents presented cough; other symptoms were scarcer. An inflammatory response was present, with median C-reactive protein at 50 mg/L. The median duration of the illness was 7 days. The rate of infection among residents was high (51%), with 5 hospitalizations (12.5%) and 1 death (2.5%). In multivariate analysis, vaccination against influenza virus appeared to emerge as associated with a probable hMPV infection, but this might be an artifact, as the proportion of unvaccinated residents was low (15%). A clear infected population profile was hard to define, although limited autonomy and low ADL score may play a role. Basic hygiene precautions were reinforced, but droplet precautions seemed difficult to apply rigorously to this population. CONCLUSIONS/IMPLICATIONS: Clinical and biological presentations were nonspecific. The rate of infection was high, highlighting the need for the rapid introduction of strict precautions to contain the infection.

First Case of Actinomycetoma in France Due to a Novel Nocardia Species, Nocardia boironii sp. nov.

Bacterial mycetoma is a neglected disease mainly observed in tropical area countries and typically associated with rural conditions, making its presence in developed countries of temperate climate areas rare. However, we report the first case of an autochthonous mycetoma case in continental France that originated from a new Nocardia species. A Gram-positive filamentous bacterium (OFN 14.177T) was isolated from a pus sample from the mycetoma of a male French patient 92 years old suffering from chronic lymphocytic leukemia. The isolate was analyzed by a polyphasic taxonomic approach by coupling morphological, biochemical, physiological, and chemotaxonomic aspects to genomic and phylogenetic analyses. Multilocus sequence analysis (MLSA) using four housekeeping genes (16S rRNA gene, secA1, hsp65, and sod) combined with phylogenetic analysis revealed that the strain OFN 14.177T is phylogenetically closer not only to Nocardia altamirensis but also to all other species comprising the Nocardia brasiliensis clade (i.e., N. brasiliensis, N. altamirensis, N. vulneris, N. iowensis, and N. tenerifensis), some of which present cutaneous tropism. The G+C content of isolate OFN 14.177T was 68.2 mol%. DNA-DNA hybridization analyses demonstrated 38.25% relative reassociation with N. altamirensis. The strain OFN 14.177T is different from the closest species at genetic and phenotypical levels, and the data obtained indicate that it should be recognized as a new species, for which the name of Nocardia boironii sp. nov. is proposed. The type strain is OFN 14.177T (= EML 1451 = DSM 101696). IMPORTANCE Bacterial mycetoma is an endemic infection in areas with tropical and subtropical climates. Thus, its presence in temperate climate areas remains rare. We report here the first case of autochthonous actinomycetoma in continental France originating from a Nocardia species other than N. brasiliensis, namely, Nocardia boironii. Considering the history of the patient, the infection source of strain OFN 14.177T may be from frequent contact with the soil over many years because of his gardening activities. The discovery of a French autochthonous Nocardia species responsible for actinomycetoma reveals the importance of considering the possibility of having autochthonous infections of this type in nontropical countries, not only imported cases from tropical countries. However, further studies are needed to elucidate the real incidence of this new species.