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Radiometer® has developed a point-of-care test for fast PCT measurement on whole blood in micromethod on a AQT90 FLEX® instrument. We have verified the analytical performances of the AQT90 FLEX® PCT assay in heparinized macrotube and EDTA microtube for pediatric use, according to modified French Society of Clinical Biology (SFBC) protocol to the requirements of the standard NF EN ISO 15189: 2012. The samples (n=61, 30 macrotubes, 31 microtubes) were analyzed by the Brahms Kryptor Compact Plus® reference method vs the AQT90 FLEX®. In a second step, we studied the stability of the PCT at room temperature for 24 h. A good correlation between the two methods on macro- or microtubes is observed (respectively r=0.990 and 0.993). The Bland-Altmann representations confirm the excellent correlation with a deviant, above the acceptable limit, which was calculated according to ISO 5725-6, for each type of tube and for the two concentration ranges (lower and greater than 1 ng/mL). The biases observed do not affect the clinical decision. No degradation of PCT after 24 h was demonstrated by the Mann and Whitney test on macro- and microtubes (p=0.50 and 0.34, respectively). The determination of PCT on AQT90 FLEX® has satisfactory analytical characteristics and can be used as point-of-care testing device on whole blood without pre-analytical treatment. In heparinized macrotube and EDTA microtube, the PCT is stable at room temperature up to 24 h.

Sickle SCAN™ is a rapid, qualitative, point-of-care lateral flow immunoassay for the identification of AS, AC, SS/Sβ0thal, SC and CC/Cβ0thal phenotype. We evaluated this test under the conditions encountered in the French newborn screening (NBS) program for sickle cell disease: a total of 104 dried blood spots (DBSs) were tested with an HPLC reference method and then with the Sickle SCAN™ device. Sickle SCAN™ identified the hemoglobin (Hb) phenotype correctly on 96% of cases. In the four non-concordant cases, the antibody anti-HbS cross-reacted with HbE (n=2), HbD (n=1) or HbX (n=1). There were no false negative. In order to test Sickle SCAN™'s sensitivity to low levels of HbA and HbS in the presence of high HbF levels, we selected another 21 DBS cards with low percentages of HbA (0.6-4.2%) and HbS (2.0-6.9%). HbA and HbS were always detected when present at levels of more than 1% and 2%, respectively. Sickle SCAN™ appears to be an accurate point-of-care method for the identification of newborns with SCD trait. The device meets the criteria for sickle cell disease NBS programs in endemic countries with poor access to laboratory equipment.

Pneumatic tube delivery system (PTS) enables to reduce considerably turnaround times. The aim of the study was to assess the influence of the PTS on the quality of routine biochemical and hematological tests in our laboratory. Blood samples from 6 hospitalized patients and 8 healthy volunteers were analyzed. Blood samples were delivered to the laboratory by a PTS and by a human courier. We performed the following analysis: ionized calcium, sodium, potassium, lactate deshydrogenase (LDH), aspartate aminotransferase (ASAT), arterial blood gas, complete blood count and coagulation test as prothrombin time, activated partial thromboplastin time, factors V and VIII. Results were compared between the both method of transport according to the recommendation of the Societe francaise de biologie clinique and the French committee for accreditation (SH-GTA01, norme NF ISO 5275-6). The hemolysis index of plasma was similar between the groups and no morphological differences were found on blood cells. For three samples, when delivered by PTS, LDH levels (two samples) and neutrophil polynuclear count (one sample) were above the recommended guidelines compared to those delivered by courier. Conversely, LDH levels and FVIII were below in two samples delivered by PTS. LDH levels, PNN count or factor VIII can be affected by PTS without the clinical interpretation being modified. We concluded that the PTS can be used to transport blood samples for routine biochemical and hematological analysis in our hospital.

Context: The principle of Sickle Scan (Biomedomics, Inc.) is a rapid, point-of-care qualitative lateral flow immuno-assay kit for the identification of sickle cell conditions of Hb A, S and C. Sickle Scan was specifically developed to allow for the identification of sickle cell trait Hb AS, heterozygotes AC, and Hb SS, Hb SC and Sβ° patients. Other sickle cell conditions as SD, SE, SO-Arab, S Lepore,… cannot be identified using Sickle Scan system. The test must be done using venous blood or capillary blood (fresh or dried blood spots). Patients and methods: Two hundred and fifty patient samples (143 adults and 107 newborns) were analyzed. All tests were performed according the manufacturer's recommendations in one laboratory by 2 observers. The reference tests used for comparison were HPLC (NBS Variant - Bio-Rad) and capillary electrophoresis (Capillarys 3 - Sebia). Results: Comments: In adult patients, the 2 observers concordantly detected the presence of Hb A, Hb S and Hb C. There were 4 differences of interpretation between them (no Hb A in a AS patient and no Hb A in 3 SS transfused patients). The percentage of Hb A in these 3 last patients was respectively 13.6%, 17.7% and 18%. There was no false positivity neither in the patient heterozygous AE nor in the patient SD. No false negativity occurred for Hb S and C. In newborns, the accuracy of the test was excellent for the identification of the phenotypes FA, FAS, FAC, FS (SS / Sβ°). The lowest detected values of Hb S and Hb C in FAS and FAC newborns were respectively 2.4 and 3.4 %. We observed an inconstant cross-reactivity of the antibody anti Hb S with the hemoglobins E and D, in respectively 3/25 FAE phenotype and 6/26 in the FAD phenotype. There was no cross reaction with hemoglobin Bart's and O-Arab. In FAS newborns the mean and extreme values of the percentage of Hb A were m=8.2 (2.6-15.5) and no difficulties occurred for the identification of these low percentages of Hb A. This observation is different from those made in adult patients for which one observer did not find Hb A in transfused patients with highest values of Hb A comprised between 13.6 and 18. Conclusions: In this series of adult and newborn patients, the Sickle Scan appeared as an accurate method for the identification of AS, AC, SS/Sβ° and SC phenotypes. False positive tests were observed in some patients with hemoglobin E or D but no false negative results were found as regards the identification of Hb S and Hb C. Table Table. Disclosures Ribeil: Bluebirdbio: Consultancy; Addmedica: Research Funding.

Objectives: The aim was to compare the in vitro effects of amoxicillin and ampicillin on the oxidative metabolism of polymorphonuclear neutrophils (PMNs). Methods: Superoxide radical anion production by PMNs, stimulated or not by various exogenous stimulants and in contact with increasing antibiotic concentrations, was measured using spectrophotometric methods. Results: Whereas a pro-oxidative action of amoxicillin on PMNs was obtained without exogenous stimulation or with opsonized zymosan (OZ), the O - 2 production by PMNs incubated with ampicillin did not increase significantly. Conclusions: This amoxicillin pro-oxidative effect could be due to the activation of the PMN NADPH oxidase, to its induction by a membrane effect or via the OZ pathway. It probably reinforces amoxicillin intrinsic bactericidal action and might partly explain the severe rashes sometimes occurring with amoxicillin treatment.