Antimicrobial susceptibility testing determined by Alfred 60/AST (Alifax®) in a multi-sites lab: performance's evaluation and optimization of workflow.

PURPOSE: New techniques are needed to speed-up the identification and antimicrobial susceptibility testing (AST) of bacteria associated with bloodstream infections. Alfred 60/AST (Alifax®, Polverara, Italy) performs AST by light scattering directly from positive blood cultures. METHODS: We evaluated Alfred 60/AST performances for 4 months. Each new episode of bacteraemia was included and AST were compared to either our rapid automated AST (Vitek® 2) or disk diffusion method. The discrepancies were investigated using Etest®. The time-to-result (TTR) was evaluated by comparing the blood volume inserted into Alfred 60/AST, i.e. 2 versus 7 blood drops. Taking into account the TTR, the workflow of positive blood cultures and the availability of AST results was studied in order to optimize the implementation of Alfred 60/AST. RESULTS: A total of 249 samples and 1108 antibiotics for AST were tested. After exclusion of unavailable results, 1008 antibiotics were analysed. 94.9% (n = 957/1008) of the antibiotics showed categorical agreement. There were 14 very major errors (VME), 24 major errors (ME) and 13 minor errors (mE). The VME were mostly related to clindamycin (64.3%) whereas meropenem and piperacillin-tazobactam constituted the major part (37.5% and 61.5%) of ME and mE respectively. Results were highly reliable for Enterobacterales and enterococci. The mean TTR ranged between 4.3 and 6.3 h and was statistically 20 min faster when applying the 7 blood drops protocol. We showed that Alfred 60/AST could give relievable results within working hours for positive blood culture which are flagged the same day between 12:00 am and 12:00 pm. CONCLUSION: Our study confirmed that Alfred 60/AST gives reliable AST results in a short period of time, especially for Enterobacterales and enterococci. AST could thus be easily obtained the same day of a positive blood culture. Clinical impact studies are mandatory to validate a 24/24 working.

[Pyogenic streptococcal omphalitis and foot's cellulitis in an 11 day old infant]. / Omphalite à Streptococcus pyogenes et cellulite du pied chez un nourrisson de 11 jours.

Omphalitis is a rare infection in our countries. Streptoccus pyogenes is one of the most frequently encountered germs. Complications are rare but include septicemia and necrotizing fasciitis with a high mortality rate. The case reported in this article is that of an 11 days old infant with pyogenic streptococcal omphalitis who developed cellulitis of left food. An intravenous antibiotic treatment allowed complete resolution of the symptoms. The article is the opportunity to review of the risk factors of this affection, its complications and treatments.

L'omphalite est une infection rare dans nos pays. Le streptocoque pyogène est un des germes les plus fréquemment rencontrés. Les complications sont rares mais incluent les septicémies et la fasciite nécrosante avec un taux important de mortalité. Le cas rapporté dans cet article est celui d'un nourrisson de 11 jours présentant une omphalite à Streptocoque pyogène ayant développé une cellulite du pied gauche. Un traitement antibiotique intraveineux a permis une résolution complète des symptômes. Cet article est l'occasion d'une revue des facteurs de risques de cette affection, de ses complications et traitements.

[Management of vaccination in children receiving an allogeneic marrow transplant]. / Prise en charge de la vaccination chez les enfants receveurs d'une greffe de moelle allogénique.

Over the last decades, significant advances in the diagnosis and therapeutics have considerably improved success rate from bone marrow transplant in patients suffering from otherwise life-threatening diseases, allowing now for prolonged survival and better quality of life after an allograft. However, infectious diseases remain one of the most serious complication in this population, hence associated with a high morbidity and mortality. Prevention, in particular through vaccination, constitutes a cornerstone of the management of immunocompromised hosts, since this procedure aims to protect them once back to life in community after long periods of hospitalization. If the necessity of vaccinating immunocompromised patients as well as their family is unequivocally recognized among health care workers, some questions remain source of debate. Several famous societies edited guidelines, but those differ from each other and cannot be transposed from a country to another without considering their local epidemiology and implemented vaccination schedule. Moreover, development and availability of new vaccines render recommendations constantly susceptible to adaptations. After exhaustive literature review, this article aims to offer pragmatic answers to the main questions raised by healthcare workers when vaccinating children after a bone marrow transplant. We here review all vaccines available and discuss their modalities of administration considering the timing after transplant, the immunological residual status and the medical history of the child. We also offer clues to optimize vaccination of patients' siblings. In addition to highlight some interrogations about future vaccines formulations, we propose here a vaccination schedule tailored for pediatric bone marrow transplant recipients in Belgium in 2017.

Au cours des dernières années, les progrès faits dans les domaines thérapeutiques et diagnostiques ont permis d'améliorer les performances des traitements par greffes de moelle osseuse, allongeant ainsi significativement l'espérance de vie des patients souffrant de maladies jusqu'alors associées à un sombre pronostic. Cependant, aujourd'hui encore, les infections restent parmi les complications les plus redoutées en termes de morbidité et de mortalité chez ces patients. La prévention et particulièrement la vaccination occupe donc une place primordiale dans la prise en charge de ces hôtes fragiles, visant à les protéger une fois leur retour à la vie en communauté envisagé après de longues périodes d'immunosuppression. Si la nécessité de vacciner les patients transplantés et leur entourage fait l'unanimité au sein des soignants, les modalités de vaccination restent encore sujettes à de maintes interrogations dans la littérature. Plusieurs sociétés réputées font état de recommandations mais celles-ci varient entre elles et ne peuvent être transposées d'un pays à l'autre sans tenir compte de l'épidémiologie locale et du schéma vaccinal préalablement implémenté. Par ailleurs, la mise à disposition constante de nouveaux vaccins nécessite une adaptation perpétuelle des diverses recommandations établies. Sur base d'une revue exhaustive de la littérature, nous tenterons dans cet article d'apporter des réponses pragmatiques aux questions fréquemment soulevées par les soignants en charge des enfants greffés de moelle osseuse. Le document détaille les différents vaccins disponibles, en discute les critères d'administration selon le délai par rapport à la greffe et le statut immunologique du patient et revoit comment optimaliser la vaccination de l'entourage. En plus de souligner certaines interrogations à suivre concernant de nouvelles formulations vaccinales à venir, l'article ci-dessous offre un schéma pratique d'administration des différents vaccins chez les enfants receveurs d'une greffe de moelle en Belgique en 2017.

[Practical problems related to the management of febrile urinary tract infection in Vietnamese children]. / Difficultés de prise en charge des infections urinaires fébriles chez l'enfant vietnamien.

BACKGROUND: To describe the practical problems related to urinary tract infection (UTI) management in febrile Vietnamese children. METHODS: During a prospective 28-month inclusion period, 143 febrile children with significant bacteriuria were treated for UTI in the nephrology department of Nhi Dong 2 children's hospital in Ho Chi Minh City, Vietnam. Patients were treated after blood and urine samples had been taken for culture, according to a local antibiotic protocol, parenterally with ceftriaxone 75mg/kg/day. Oral treatment with cefixime 8mg/kg/day was started after 48h of apyrexia for 2 weeks. According to local protocol, antibiotic therapy was only changed if children did not respond clinically to treatment regardless of antibiogram results. RESULTS: Among these 143 children, 51% were girls and 80% of them had their first UTI before the age of 2 years. The commonest causative agent was Escherichia coli (80% of cases) with a high resistance rate to ampicillin (91%) and cotrimoxazole (74%). Extended-spectrum ß-lactamase (ESBL) production was observed in 52% of Enterobacteriaceae isolates. According to antibiotic susceptibility, the initial treatment with ceftriaxone was found to be inappropriate in 63% of cases. CONCLUSIONS: E. coli was responsible for 80% of UTIs in Vietnamese children with a high rate of resistance to first-line antibiotics. ESBL production was found to be extremely high in this study. Based on these data, we propose a new empiric treatment schedule for Vietnamese children suspected of UTI.

Streptococcus pneumoniae serotype 1 burden in the African meningitis belt: exploration of functionality in specific antibodies.

Streptococcus pneumoniae serotype 1 (Sp1) constitutes an important cause of seasonal endemic meningitis in all age groups in the African meningitis belt. Despite a higher meningitis incidence, the Burkinabé population has an Sp1-specific antibody seroprevalence similar to that reported in the United Kingdom (UK). We aimed to establish whether the opsonophagocytic activity (OPA) of pneumococcal IgG naturally present in Burkina Faso differs from that seen in individuals in the UK and to compare the OPAs generated by natural and vaccine-induced immunity. Samples collected from pneumococcal vaccine-naive Burkinabé and UK subjects were matched for age (1 to 39 years) and anti-Sp1 IgG level, analyzed for OPA to 3 S. pneumoniae serotypes (1, 5, and 19A), and compared to postvaccine samples. Furthermore, the Burkinabé samples were assessed for IgG avidity and serotype-specific IgM concentrations. One hundred sixty-nine matched serum samples from both populations were selected. A greater proportion of Burkinabé subjects aged 1 to 19 years had functional Sp1 activity (OPA ≥ 8) compared to UK subjects (12% versus 2%, P < 0.001); however, the proportions were similar among adults (9%). The correlation between Sp1 IgG concentration and OPA was good (P < 0.001), but many individuals had nonfunctional IgG, which was not related to avidity. While the Sp1 IgM concentrations correlated with OPA, not all of the function in serum samples with low IgG could be attributed to IgM. Finally, vaccine-induced Sp1-specific IgG was more functional than equivalent amounts of naturally occurring IgG. In conclusion, despite a substantially higher pneumococcal meningitis incidence, no decreased functional immunity to Sp1 could be evidenced in the Burkinabé population compared to that in the population from the UK. Furthermore, the naturally induced antibodies were less functional than vaccine-induced antibodies.

[Is it necessary to vaccinate against varicella?]. / Faut-il vacciner contre la varicelle?

Varicella is a frequent viral disease, with a substantial medical and societal impact. For many years, various industrialized countries have adopted an universal mass vaccination against varicella, using a one-dose schedule. In these countries, the global incidence of varicella has decreased by about 90%. A significant reduction in hospitalizations, outpatient visits and medical costs due to varicella has also been observed. Recently, a 2-dose schedule has demonstrated an efficacy of about 98%, as well as herd immunity.

Dynamic pattern and genotypic diversity of Staphylococcus aureus nasopharyngeal carriage in healthy pre-school children.

OBJECTIVES: It is common wisdom that persistent carriage of Staphylococcus aureus is more frequent in young children than in adults. The objectives of this study were to assess the S. aureus temporal carriage pattern among a healthy community of pre-school children, with concomitant description of genotype diversity, toxin-encoding genes and antibiotic resistance. METHODS: Among 333 children 3-6 years of age, S. aureus nasopharyngeal carriage was assessed over one school year by culture of three sequential nasopharyngeal aspirates. Identification, methicillin resistance and toxin production profile were determined by PCR. Genotyping was performed by spa sequencing and multilocus sequence typing (MLST). RESULTS: Out of 830 samples collected, 286 (34%) yielded S. aureus from 185 carriers (55%). Based on consecutive genotype analysis, only 40/268 (15%) children could be classified as persistent carriers, and the remaining 118 (44%) showed intermittent carriage. spa typing revealed 82 types clustered into 13 spa clonal complexes (CCs). Fourteen strains isolated from 11 (3%) children were methicillin-resistant S. aureus (MRSA), half of these strains belonged to the commonly hospital-associated spa t008-ST8-SCCmec IV. Methicillin-susceptible S. aureus (MSSA) were genotypically more diverse. Toxic shock syndrome toxin and egc1/2 complexes were highly prevalent (24%). Contrastingly, Panton-Valentine leucocidin (PVL) was carried only by three MSSA strains (0.6% of children). Exfoliative toxins were detected in 10 (3.5%) MSSA strains, of which 5 were related to the impetigo clone CC121. CONCLUSIONS: Although S. aureus nasopharyngeal carriage was high among healthy pre-school children, persistent carriage seems to be less frequent than previously reported. The prevalence of MRSA carriage was 3%, but was not associated with PVL.