Epidemiological data of staphylococcal scalded skin syndrome in France from 1997 to 2007 and microbiological characteristics of Staphylococcus aureus associated strains.

Epidemiological data on staphylococcal scalded skin syndromes (SSSS), including bullous impetigo (BI) and generalized exfoliative syndrome (GES), are scarce. To better characterize SSSS and associated Staphylococcus aureus strains, we conducted a retrospective study of 349 cases collected in France between 1997 and 2007 by the National Reference Centre of Staphylococci. Our results showed a stationary evolution of SSSS cases, with a heterogeneous distribution of cases in France. Although notification was not exhaustive, we estimated an incidence of 0.56 cases/year/million inhabitants, in accordance with previous studies conducted in France and Europe, with a median age of 2 years old and sex ratios of 1. A seasonal effect was observed, with a higher GES/BI ratio in autumn compared with other seasons, which could be explained by the impact of viral co-infection. Genetic analysis of S. aureus strains showed that accessory gene regulator (agr) 4, exfoliative toxin A (eta) and B (etb) genes, staphylococcal and enterotoxin-like O (selo) gene and agr4 etb selo profiles were predominantly associated with GES, whereas agr2 eta and agr4 eta selo were more frequently observed with BI. Only one methicillin-resistant strain was found. Protein A (spa) typing identified two main genotypes: spa clonal complex (CC) 159/sequence-type (ST) 121 (75%) and spaCC346/ST15 (18%). spaCC159 was mainly associated with agr4 eta etb selo, agr4 eta selo and agr4 etb selo, and spaCC346 was mainly associated with agr2 eta, suggesting that French SSSS cases are caused by these two main lineages. However, in a multivariate analysis, only etb was independently associated with GES.

Serum antibodies against Panton-Valentine leukocidin in a normal population and during Staphylococcus aureus infection.

To determine whether Staphylococcus aureus Panton-Valentine leukocidin (PVL) is expressed during human infection, anti-PVL antibody titres were compared in patients with PVL-positive and PVL-negative staphylococcal infections, and in patients with no evidence of S. aureus infection. Patients with PVL-positive strains had higher levels of anti-PVL antibodies than individuals of both control groups. The median anti-PVL titre increased 8.6-fold during the course of PVL-positive infection and 1.4-fold during PVL-negative infection. These results indicate that only PVL-positive S. aureus strains elicit significant anti-PVL antibody production in humans, and demonstrate the production of PVL during PVL-positive S. aureus infection. The protective role of this immune response remains to be established.

Panton-Valentine leukocidin is expressed at toxic levels in human skin abscesses.

Pus samples were prospectively collected from patients with Staphylococcus aureus skin infections and tested for Panton-Valentine leukocidin (PVL). PVL was detected at concentrations that were toxic for rabbit skin in all specimens from patients infected with strains harbouring PVL genes.

Circadian changes in anticoagulant effect of heparin infused at a constant rate.

Six patients with venous thromboembolism were treated with heparin, administered intravenously by a constant infusion pump. The initial daily dose of heparin was adjusted to keep the activated partial thromboplastin time, sampled at 0800, between 1.5 and 2.5 times the control level. Once that level was obtained, this dose was kept constant. Anticoagulation was thereafter measured, every four hours for 48 hours, by activated partial thromboplastin time, thrombin time, and coagulation factor Xa inhibition assay. The results of all three coagulation tests showed a circadian variation in the six patients. Maximum values were achieved at night and minimum values in the morning. These circadian variations were reproduced for two consecutive days. Differences between night and morning values reached almost 50% for activated partial thromboplastin time, 60% for thrombin time, and 40% for factor Xa inhibition assay. This circadian variation resulted from two rhythms, a circadian rhythm lasting 24 hours and an ultradian rhythm lasting 12 hours, which were detected by cosinor analysis for each coagulation test (p less than 0.01). A circadian rhythm was detected individually in most of the patients for each coagulation test (p less than 0.05). All patients had a nocturnal peak in activated partial thromboplastin time on both days. In four patients this peak exceeded the upper desired limit of activated partial thromboplastin time. These rhythms should be taken into account when evaluating the dosage of heparin to be administered.

[Nycthemeral change in the anticoagulant effect of heparin given at a constant rate by the intravenous route]. / Variation nycthémérale de l'effet anticoagulant de l'héparine administrée à débit constant par voie intraveineuse.

Six subjects with venous thromboembolism volunteered for this prospective study. Heparin was administrated intravenously at a constant rate with an infusion pump. The activated partial thromboplastin time (A.P.T.T.) and thrombin time (T.T.) were measured every 4 hrs. for 48 hrs. These coagulation tests exhibited a nycthemeral variation with a large amplitude which was reproducible from one day to the next and statistically validated by the cosinor method (p less than 0.001). All patients had a nocturnal peak of A.P.T.T. and T.T. on both days. In four patients this peak for A.P.T.T. exceeded the upper desired limit.

Factor VII Padua 1. Another case.

A patient with a peculiar factor VII is described. The propositus is a 70-year-old man without any bleeding tendency. The coagulation pattern is characterized by a prolonged rabbit brain prothrombin time, a normal Stypven cephalin clotting time and a normal thrombotest. Factor VII activity is low when assayed using rabbit brain the thromboplastin but is normal when assayed using ox brain thromboplastin. The neutralization test performed with an antifactor VII antiserum revealed a normal factor VII antigen level. A pedigree study has not been possible, the patient having no living relatives. No differences were observed between the biological results of our patient and those described by Girolami as factor VII + Padua.

[Comparative study of three commerical preparations for the detection of Australia antigen]. / Etude comparative de trois réactifs commercialisés de détection de l'antigène HB

2,944 sera from blood donors (420 of them being new donors) were tested in four techniques: Counterelectrophoresis (CEP) and three commercial tests: Ausria II, Auscell and Hepanosticon. Over 10 HBs Ag detected by RIA, 8 were evidenced by the Auscell test and 6 by the Hepanosticon Test. False positive results (approximately 3%) represent a disadvantage to the reverse hemagglutination method; this rate increased considerably in a group of 386 patients sera also tested. The authors conclude that the results obtained with the reverse hemagglutination technique are nearing those of RIA.