Impaired secretion of platelet granules in patients with Duchenne muscular dystrophy - results of a prospective diagnostic study.

A tendency to bleed during scoliosis surgery has been reported repeatedly in Duchenne muscular dystrophy (DMD) and diagnostic studies show a prolonged bleeding time. The pathophysiological background is still not fully understood. The short dystrophin isoform dp71 is expressed in platelets and mediates contractile properties. We performed a bicentric, non-blinded, prospective diagnostic study in 53 patients with confirmed DMD. Extensive laboratory analyses included platelet aggregometry and platelet flow cytometry, as well as routine coagulation analyses. Results of laboratory diagnostics were correlated with clinical data. Patients were subgrouped and analyzed according to ambulatory status and cardiac involvement. Platelet aggregation was reduced after stimulation with ADP (adenosine triphosphate) [60%; reference range 66-84%]. In addition, in the DMD cohort the expression of platelet activation markers CD62 and CD63 (flow cytometry analyses) was significantly lower than in healthy controls, most prominent in non-ambulatory patients with cardiac involvement. There was no clear association with the location of the underlying mutations in the dystrophin gene. No further abnormalities were identified regarding primary or secondary hemostasis. This study shows that platelets of patients with DMD have decreased expression of CD62 and CD63 which are markers for platelet granule release. This may indicate that patients with DMD have an impaired platelet granule secretion which may explain to some extent the increased bleeding, especially in mucocutaneous areas and perioperatively.

[Epidemiology of myopia]. / Epidemiologia krótkowzrocznosci.

The present state of knowledge on the epidemiology of myopia is discussed. The history of myopia investigations is described. The prevalence of myopia in different ages, races and populations is presented. The factors influencing myopia occurrence are characterized. Special attention is focused on the results of studies indicating environmental and genetic reasons of myopia. Most recent investigations concerning the influence of light on myopia occurrence as well as concerning a genetic locus for high myopia are described.

[Urinary tract infections: observations on 19,021 patients hospitalized in Sassari Province]. / Le infezioni delle vie urinarie: osservazioni su 19,021 soggetti ospedalizzati in provincia di Sassari.

We report the results of a study carried out upon samples of urine from 19,021 patients in various departments of medical school in Sassari and in the hospitals of Alghero and Ozieri. The 34.7% of samples examined proved to be positive. Among these we isolated Escherichia coli (32%), Proteus spp. (24%), Staphylococcus (12%), Klebsiella-Enterobacter-Serratia (KES) spp. (9%), Pseudomonas spp. (5%). We found microbic associations in 11% of cases. We also studied the sensitivity of microorganisms to various chemoantibiotics, and the efficacy of therapy on 964 patients. In the various checks made, the results point out a persisting positivity (53%). E. coli strains show a major sensitivity to the various antibiotics (aminoglycosides, quinolones, cephalosporins, etc.); Proteus spp. and KES are less sensitive; Pseudomonas spp. strains are very resistant and respond mainly to norfloxacin and ceftazidime.

[Epidemiological study of a group of staphylococci isolated in a hospital environment]. / Studio epidemiologico di liogruppi di stafilococchi isolati in ambiente ospedaliero.

A survey has been carried out on 336 strains of staphylococci isolated in a hospital environment in order to assess the validity of the lyogroup classifying method, to know their epidemiological behavior in our territory and to test their sensitivity to various antibiotics. The findings of the survey can be summed up as follows: the practical test for bacteriolysis activity appears to be a valid method of identifying staphylococci in so far as it allows to classify them, but also to differentiate them from micrococci; lyogroup VI appears to be prevalent both as a whole and in nearly all materials of origin; the incidence of resistance is highest for piperacillin (47%), gentamicin (20%), tobramycin (19%); it is lowest for netilmicin (1.2%) and amikacin (2.6%); among meticilline resistant strains (18%) there is a marked resistance towards nearly all antibiotics tested.