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Molecular diagnosis on nasopharyngeal swabs (NPS) is the current standard for COVID-19 diagnosis, but saliva may be an alternative specimen to facilitate access to diagnosis. We compared analytic performances, feasibility and acceptability of NPS, saliva, and oral-self sampling swab for the detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). A prospective, multicenter study was conducted in military hospitals in France among adult outpatients attending COVID-19 diagnosis centers or hospitalized patients. For each patient, all samples were obtained and analyzed simultaneously with RT-PCR or transcription-mediated amplification method. Clinical signs, feasibility, and acceptability for each type of sample were collected. A total of 1220 patients were included, corresponding to 1205 NPS and saliva and 771 OS. Compared to NPS, the sensitivity, specificity, and kappa coefficient for tests performed on saliva were 87.8% (95% CI 83.3-92.3), 97.1% (95% CI 96.1-98.1), and 0.84 (95% CI 0.80-0.88). Analytical performances were better in symptomatic patients. Ct values were significantly lower in NPS than saliva. For OS, sensitivity was estimated to be 61.1% (95% CI 52.7-69.4) and Kappa coefficient to be 0.69 (95% CI 0.62-0.76). OS was the technique preferred by the patients (44.3%) before saliva (42.4%) and NPS (13.4%). Instructions were perceived as simple by patients (90%) for saliva and OS. Finally, the painful nature was estimated to be 0.9 for OS, on a scale from 0 to 10, and to be 5.3 for NPS. Performances of OS are not sufficient. Saliva is an acceptable alternative to NPS for symptomatic patient but the process required additional steps to fluidize the sample.

Background Mycobacterium canettii forms part of the Mycobacterium tuberculosis complex. Mycobacterium canettii infections are mainly described in the Horn of Africa. The permanent presence of French soldiers in Djibouti raises the question of the risk of being infected with M. canettii. Here, we describe M. canettii infections among French military and their families between 1998 and 2015. Methods This retrospective study relied on 3 sources of data: the reference center for mycobacteria in the Biology Department at Percy Military Hospital in Paris, the French Military Center for Epidemiology and Public Health, and the scientific literature. After an exhaustive census of the strains, we studied the epidemiological data on 20 cases among French soldiers and their families. Results Twenty cases of M. canettii infections are reported, including 5 unpublished cases. Adenitis predominates (n = 15), especially in the cervico facial area and among children; 1 case was observed 1 month after dental care in Djibouti. The pulmonary forms were less frequent (n = 6), and 3 atypical forms are described. All patients had stayed in Djibouti. Conclusions Cases of M. canettii infection among the French military consisted mainly of adenitis; disseminated forms were possible with immunodeficiency. Their evolution under specific treatments was comparable to that of tuberculosis. The presumed origin of the infection seemed to be environmental, possibly a water reservoir, and not due to human-to-human contagion.

The Alere-i™ Influenza A&B (Abbott), a nicking endonuclease amplification reaction test, has recently been improved in order to deliver results in a few minutes. Our field observation highlights two problems with this new version: improper interpretation of a test as valid despite improper reagent hydration and falsely influenza B positive results. We advise users of the new system to check reagent hydration prior to reporting a result and to systematically confirm positive influenza B results.

Nous rapportons le cas d’une patiente asymptomatique presentant une hypokaliemie severe chronique d’origine renale. Apres elimination d’une prise de diuretique, les hypotheses evoquees devant l’hypokaliemie associee a une alcalose metabolique chez une patiente sans hypertension arterielle sont un syndrome de Bartter ou un syndrome de Gitelman. La mise en evidence d’une magnesemie basse et d’une hypocalciurie oriente fortement vers le syndrome de Gitelman qui sera conforte dans un premier temps par les resultats des explorations fonctionnelles renales et confirme par l’identification en biologie moleculaire d’une mutation homozygote connue du gene SLC12A3. L’enquete familiale a par ailleurs permis d’identifier la meme anomalie chez la sœur cadette de la patiente. Un traitement par diuretique epargneur de potassium associe a une supplementation en magnesium et potassium a ete instaure chez ces deux patientes. Ce cas clinique illustre la difficulte diagnostique du syndrome de Gitelman d’une part du fait de sa frequente confusion avec le syndrome de Bartter dont il se distingue essentiellement par son impact sur la magnesemie et la calciurie et, d’autre part, du fait du caractere souvent asymptomatique de cette maladie responsable d’une sous-estimation probable de sa prevalence.

Streptococcus pneumoniae has been rarely considered as an infectious agent in appendicitis. We report a case of a 47-year-old woman with acute appendicitis caused both by serotype 35B S. pneumoniae and Klebsiella pneumoniae. The pathway of the appendix colonisation remains unclear. It could be explain by direct infection via mucosal translocation or by hematogenous spread. Pneumococcal appendicitis could progress to perforation more frequently. The use of intraoperative samples for management of appendicitis is controversial. But, culture with appropriate media is the only mean to isolate bacteria not very often encountered in appendicitis and to identify species of epidemiologic interest as serotype 35B S. pneumoniae, a non vaccinal serotype resistant to penicillin which is considered as a potential emergent pathogen. In the case of S. pneumoniae appendicitis, it could be recommended to take complementary directed samples to understand its pathophysiology.

Objectives: To examine the effect of subinhibitory concentrations (sub-MICs) of antistaphylococcal drugs on Panton-Valentine leucocidin (PVL), α-haemolysin (Hla) and protein A (SpA) expression by community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA). Methods: Five clinical isolates representing the main worldwide CA-MRSA clones were grown with sub-MICs (1/8, 1/4 and 1/2 MIC) of five antibiotics (clindamycin, daptomycin, linezolid, tigecycline and vancomycin). After 4 and 6 h of incubation, culture pellets were used for relative quantitative RT-PCR with primers specific for pvl, hla, spa and gyrB. The PVL, Hla and SpA concentrations were measured in the supernatant (for PVL and Hla) and in the cell pellet (for SpA) using specific ELISAs. Results: For all strains tested, clindamycin and linezolid dramatically reduced mRNA levels of PVL and SpA. Tigecycline also decreased the PVL and SpA mRNA levels of 3/5 and 4/5 strains tested, respectively, whereas daptomycin and vancomycin had no significant effect. PVL and SpA quantification confirmed the concentration-dependent inhibition of PVL and SpA production by clindamycin and, to a lesser extent, by linezolid and tigecycline. Only clindamycin decreased Hla mRNA expression, whereas linezolid, tigecycline and daptomycin showed heterogeneous strain-dependent results, and vancomycin had no significant effect. Analysis of the Hla level revealed a stronger concentration-dependent inhibition of Hla release by clindamycin than by linezolid. Conclusions: The effect of sub-MICs on virulence expression depended on the antibiotic and the virulence factor. Clindamycin and linezolid consistently suppressed the expression of different virulence factors by CA-MRSA, whereas tigecycline specifically suppressed PVL expression. Daptomycin and vancomycin seem to have no significant effects at these concentrations.

Amebiasis, the parasitic disease caused by Entamoeba histolytica, may result in extra-intestinal diseases among which liver abscess is the most common manifestation. We report two cases of amebic liver abscess illustrating the inequal sensitivity of serologic tests detecting anti-amebic antibodies.