Shotgun metagenomic screening to improve the retrospective diagnosis of undocumented intrauterine infections on embedded placenta samples: Lessons from a brucellosis case.

BACKGROUND: Microbiological diagnosis of intrauterine infections (IIU) still relies on bacteriological cultures or targeted DNA amplification lacking in sensitivity. Shotgun metagenomics (SMg) is an emerging unbiased molecular approach that makes it possible to sequence all the nucleic acids from any sample. It had never previously been used for IIU. METHODS: We here report the case of a patient with an unexplained IIU and fetal loss that could be documented by a combined SMg/microbiological approach, leading to the diagnosis of maternal brucellosis. RESULTS: A 31-year-old woman presented with an undocumented IIU with fetal loss at 24 weeks of gestation. Culture-based work-up failed to identify the pathogen involved. Paraffin-embedded placenta sample was retrospectively analyzed by SMg. Brucella spp nucleic acids were detected, and subacute maternal brucellosis was confirmed by targeted PCR and serological testing. CONCLUSION: This case provides grounds for further utilization of SMg for the microbiological diagnosis of unexplained obstetrical infections.

SPILF update on bacterial arthritis in adults and children.

In 2020 the French Society of Rhumatology (SFR) published an update of the 1990 recommendations for management of bacterial arthritis in adults. While we (French ID Society, SPILF) totally endorse this update, we wished to provide further information about specific antibiotic treatments. The present update focuses on antibiotics with good distribution in bone and joint. It is important to monitor their dosage, which should be maximized according to PK/PD parameters. Dosages proposed in this update are high, with the optimized mode of administration for intravenous betalactams (continuous or intermittent infusion). We give tools for the best dosage adaptation to conditions such as obesity or renal insufficiency. In case of enterobacter infection, with an antibiogram result "susceptible for high dosage", we recommend the requesting of specialized advice from an ID physician. More often than not, it is possible to prescribe antibiotics via the oral route as soon as blood cultures are sterile and clinical have symptoms shown improvement. Duration of antibiotic treatment is 6 weeks for Staphylococcus aureus, and 4 weeks for the other bacteria (except for Neisseria: 7 days).

[Hemophagocytic lymphohistiocytosis with granulomatosis and diffuse T-cell infiltration associated with disseminated Nocardiosis and pulmonary infection due to Streptomyces spp]. / Syndrome d'activation macrophagique associé à une granulomatose et une infiltration lymphocytaire T CD4 diffuse révélant une nocardiose disséminée et une infection pulmonaire à Streptomyces spp.

INTRODUCTION: Hemophagocytic lymphohistiocytosis (HLH) is a rare syndrome frequently secondary to infectious disease, especially in immuno-compromised patients. We report a HLH secondary to disseminated nocardiosis and Streptomyces spp pulmonary infection. CASE REPORT: A 69-years-old women had recent subcutaneous nodules of the forearms and loins associated with peripheral neuropathy and pulmonary nodule of the right upper lobe. Cutaneous biopsy revealed granuloma. Cutaneous lesions worsened and the patient developed a HLH with probable cardiac and neurological involvement, associated with cutaneous granulomatosis and diffuse polyclonal lymphocyte proliferation. Nocardia PCR was positive in cutaneous biopsy. Pulmonary samples revealed Streptomyces in culture and Nocardia in PCR. The evolution under antibiotic treatment was favorable. CONCLUSION: Recent diagnosis of HLH without obvious etiology should lead to etiological investigation, including the search for infections with slow-growing bacteria such as Nocardia or Streptomyces spp.

Assessing the benefit of the 72-hour antibiotic therapy reassessment documentation.

OBJECTIVES: To assess the documentation of the 72-hour antibiotic therapy reassessment in medical records. METHODS: One-day prevalence evaluation of curative antibiotic therapies≥72hours. The documentation of the reassessment was defined according to three criteria: (1) "clear" documentation (clinical or microbiological comment associated with a comment on the need to adjust the antibiotic therapy or on the lack of need); (2) "tacit" documentation (only based on a clinical or microbiological comment); (3) no documentation. RESULTS: We assessed 114 antibiotic therapies in 26 hospital departments. A clear reassessment at 72hours was observed in only 45 (39%) records and 31 (27%) records had no reassessment. The planned duration of treatment was written in 63 (55%) records. At 72hours, among the 71 antibiotic therapies with a microbiological documentation, 69 (97%) were active and 44 (62%) had a narrow spectrum. Among the 48 antibiotic therapies with a broad spectrum on day 1, only 21 (44%) benefited from a de-escalation at 72hours. A clearly recorded reassessment at 72hours was associated with de-escalation (P=0.025) and the prescription of a planned duration of treatment was associated with antibiotic therapy compliance with local or national guidelines (P=0.018). CONCLUSION: Although reassessment was observed in 73% of records, it was correctly recorded at 72hours in only 39% of cases. The documentation of the reassessment and the prescription of a planned duration were associated with a better quality of antibiotic prescription (de-escalation, compliance with guidelines) and are relevant indicators for monitoring the proper use of antibiotics.

[History and principles of vaccination]. / Histoire et principes de la vaccination.

INTRODUCTION: Vaccination constitutes a major advance in the prevention of infectious diseases. The principle of vaccination is to induce protection against a pathogen by mimicking its natural interaction with the human immune system. The vaccine reduces the risk of complications and mortality following subsequent exposure to an infectious agent. STATE OF THE ART: In this review we recall the history of vaccination as well as the basic immunological principles underlying the composition of vaccines and the response to vaccination. In this way, vaccines induce the immune system to produce an immunological memory based on T and B lymphocytes in order to produce a rapid and effective response to exposure to the targeted pathogen. OUTLOOK: The improvement of existing vaccines and the discovery of new vaccines requires an understanding of the immunological principles of vaccination. Great challenges remain, particularly in terms of target pathogens for future vaccine candidates and also the acceptance of vaccination. CONCLUSION: Understanding the principles of vaccination allows development of vaccines and the control of infectious diseases.