Burkholderia cepacia complex in cystic fibrosis and non-cystic fibrosis patients: identification of a cluster of epidemic lineages.

This study was performed in order to compare Burkholderia cepacia complex strains from cystic fibrosis (CF) and non-CF patients at the genomovar, genetic and epidemiological levels. A total of 92 B. cepacia respiratory tract isolates were obtained from patients attending the following CF centres: Catania and Palermo, Sicily; Gualdo Tadino, Central Italy, and Milan, Northern Italy. A total of 23 B. cepacia isolates were obtained from blood, surgical wound, and intravenous catheter sources of patients without CF, hospitalized in Catania and Varese, Northern Italy. Genomovar status identification, clonality and genetic relatedness determination, antibiotic susceptibility pattern determination and electron microscopy were performed. Transmission of infection was shown in both CF and non-CF patients by identifying clonality of responsible strains. In total 13 clones were involved in cross-transmission episodes. No outbreak was described involving both CF and non-CF patients. The present study indicates the existence of a distinct cluster of strains responsible for epidemics in CF and non-CF patients, based on their genetic relatedness, distinct from strains associated with no or negligible transmissibility. This result suggests that transmissibility is not only associated with a specific genomovar in CF patients, but also with a group of genetically related lineages in CF and non-CF patients. A key role is shown for both segregation measures and careful surveillance of infection, based on selective culture, molecular identification and epidemiological characterization of individual isolates.

Characterization of non-type B Haemophilus influenzae strains isolated from patients with invasive disease. The HI Study Group.

Forty-one non-type b Haemophilus influenzae isolates from cases of invasive disease were characterized. By PCR capsular genotyping, 33 nonencapsulated strains, 4 type f isolates, and 4 b(-) strains were identified. By pulsed-field gel electrophoresis, the nonencapsulated isolates exhibited great genetic heterogenicity, whereas the type f and the b(-) strains seemed to have a clonal spread. Occurrence of the hifA gene was found by PCR in 18% of the nonencapsulated, 50% of the b(-), and all of the type f strains. Hemagglutinating fimbriae were generally expressed by nonencapsulated isolates when fimbrial gene hifA was present. Two nonencapsulated isolates not susceptible to ampicillin were detected; no strains were positive for beta-lactamase production.

Escherichia coli: effect of fosfomycin trometamol on some urovirulence factors.

The aim of our study was to evaluate the interference of fosfomycin trometanol (F.T.), at subinhibitory concentrations (1/4 and 1/8 MICs), on some urovirulence factors of Escherichia coli (12 strains). We tested fimbriae production, adhesion to uroepithelial cells, hydrophobicity, motility and hemolysin production of E. coli grown in the presence or absence of F.T. The strains tested, grown in the presence of F.T. (1/8 MIC), were less capable of adhering to uroepithelial cells, had less hemagglutination and reduced motility. This behavior was enhanced at 1/4 MIC of F.T. The hemolysin production and hydrophobicity properties present in some of our tested strains also were significantly decreased when the E. coli were grown in the presence of sub-MIC concentrations of F.T. These results suggest that F.T. may be of clinical use as treatment for acute urinary tract infection and in pyelonephritis prophylaxis.

Antimicrobial resistance among clinical isolates of Haemophilus influenzae in northern Italy. Collaborative Study on Pediatric Infectious Diseases.

Only scanty data are available on the susceptibility of Haemophilus influenzae in Italy. The in vitro activity of ampicillin, ampicillin-sulbactam, cefaclor, cefuroxime, cefotaxime, chloramphenicol, erythromycin and trimethoprim-sulfamethoxazole against 327 strains of Haemophilus influenzae (55 encapsulated, 272 non-typeable) isolated from adults and children in northern Italy, between January 1984 and December 1989, was compared. Patients were affected by meningitis or other invasive infections, conjunctivitis, otitis, sinusitis, pneumonia or bronchitis. Minimal inhibiting concentrations were determined by a microdilution technique in Mueller Hinton broth supplemented with 10 microliters/ml NAD and 2-5% lysed horse blood. A concentration of 1 x 10(5) to 5 x 10(5) CFU/ml was used as the inoculum. The antibiotics were tested at concentrations ranging from 0.03 to 64 microliters/ml with the exception of trimethoprim-sulfamethoxazole, for which the range of concentrations examined were 0.01/0.25 to 32/512 microliters/ml. All the strains tested were susceptible to ampicillin-sulbactam, cefuroxime and cefotaxime, and more than 95% were susceptible to ampicillin, cefaclor and chloramphenicol. Only 4% were susceptible to erythromycin but most minimal inhibiting concentrations fell into the intermediate category. Strains isolated from adults were more susceptible to trimethoprim-sulfamethoxazole than strains isolated from children (85% vs 66%; p = 0.011).

In-vitro susceptibility of Haemophilus influenzae to loracarbef (LY 163892) and other oral antibiotics. Collaborative Study Group on Pediatric Infectious Disease in Lombardy.

Data on susceptibility of Haemophilus influenzae are scanty in Italy. We compared the activity of loracarbef (Ly 163892), a new carbacephem, with that of 4 other agents against 265 strains of H. influenzae (46 type b, 219 nontypable) isolated from adults and children at Istituti Clinici di Perfezionamento of Milano, between 1/1/84 and 1/1/89, and also from 7 children at pediatric departments in Lombardy during 1988. In adults 72 strains were all isolated from sputum of patients with pneumonia or chronic bronchitis; in children 199 strains were isolated from conjunctiva (53% of the patients had also a concomitant respiratory infection), 24 from middle ear, 18 from sputum and 32 from blood or cerebrospinal fluid. Minimal inhibiting concentrations (MIC) were determined by the broth microdilution technique. The incidence of resistance of H. influenzae to ampicillin was 3.8%; the lowest percentage of resistance was found for loracarbef (0%) and the highest for erythromycin (94% for strains isolated from children and 97% for strains isolated from adults).

[Effect of the emotional state on immune functions: study on firstborn children on the occasion of the birth of a sibling]. / Influenza degli stati emotivi su funzioni immunitarie: studio in bambini primogeniti in occasione della nascita di un fratello.

The eventuality that a particular emotional involvement could weigh heavily on a person's psychophysical welfare, assuming a complementary role in the appearance of clinically noticeable pathologies (infections, allergies, neoplasms) has been object of several hypotheses which have been confirmed in researches on animals. Our research, by examining an unavoidable and surely natural situation like that one of the birth of a brother for a first born, a particularly severe for what affectivity is concerned, had the aim to evidence if there were some biological expressions, able to quantitatively settle the eventual immune functions' alterations indicative of a preexistent equilibrium. With this purpose have been examined several biological expressions indicative of immune functions (B lymphocytes, T lymphocytes, NK cells, lymphocyte transformation, chemotaxis, phagocytosis, C3 Complement fraction) in three first-born children with 2 to 3 years of age, whose mothers had in course a second pregnancy, during a period of about 20 months (from III pregnancy month to XIV month of age of the brother). The evolution of these immune functions evidence, during the whole period of observation, a non univocal performance. In the most of the cases was evidenced a variation towards diminution of the biological expression of some functions (lymphocyte transformation, T3 lymphocytes, T4 lymphocytes, T4/T8 rate, "E" Rosettes, chemotaxis and phagocytosis), while in the case of NK cells there were also variations towards augmentation. Particularly important were the variations towards diminution, that biological expressions as lymphocyte transformation and "E" Rosettes undergo. In two children the variations, towards diminution, showed themselves already before the birth of the brother. The variation of the T3 and T4 lymphocytes, of the T4/T8 rate, of chemotaxis and of phagocytosis were more limited. The values of the other examined biological expressions (T8, B7, C3) were in the normal range during the whole period of observation. Our results let us to attribute to emotional events, as in experimented model, the capacity to affect the biological expression that measures some immune functions, by depressing them in most of the cases, so in way to adulterate the immune equilibrium, and by setting the premises to upset the capability of immune defense in the examined persons. Our observations lead us to think that effectively, an event during which an important emotional state is induced, by upsetting the immune equilibrium, could more predispose a child (in this case the first born) to the action of pathogens.

In-vitro postantibiotic effects of miocamycin and erythromycin on gram-positive cocci.

The capability of miocamycin to induce a postantibiotic effect (PAE) on a Group A Streptococcus beta-haemolyticus clinical isolate and on Staphylococcus aureus ATCC 29213 has been studied. Erythromycin was chosen as a reference molecule. The exposure time to antibiotics was 90 min. The removal technique of the antibiotic agents consisted of a 1:200 dilution in cultural broth. Miocamycin displayed a PAE of 2 h 30 min in relation to the minimum inhibitory concentration (MIC) of Streptococcus and a PAE of 2 h 30 min in relation to the MIC of Staphylococcus. The PAE value lasting longer than the others was of 5 h 40 min towards Streptococcus and of 4 h 18 min towards Staphylococcus at a concentration eightfold the MIC. Erythromycin showed a PAE of 1 h 36 min in relation to the MIC of Streptococcus and a PAE of 1 h 30 min in relation to the MIC of Staphylococcus. The PAE value lasting longer than the others was of 3 h 15 min against Streptococcus and of 2 h 30 min against Staphylococcus at a concentration eightfold the MIC. In some cases a PAE was observed in relation to subinhibitory concentrations (1/2 MIC). Miocamycin therefore proved to possess a more evident capability to induce a PAE against the clinical isolate of Group A Streptococcus beta-haemolyticus and on Staphylococcus aureus ATCC 29213 than did erythromycin.

[Validity limits of data on secretory IgA]. / Limiti della validità dei dati relativi alle IgA secretorie.

Secretory IgA (sIgA) in saliva, and sometimes in expectoration, have been titrated in various groups of persons, both in pediatric age and in adults, by means of radial immunodiffusion technic. The aim was to find differences among sIgA levels in the course of respiratory tract infections, both acute and chronic, in consequence of treatment with Erythromycin (in children and in adults) in consequence of surgical intervention (in adults). Adjunctive aim was to establish if it was possible to recognize hereditary of the character that remark the predisposition to produce high sIgA quantities. The very high variability of the data collected in the various occasions and situations allowed serious doubts about the possibility of use of the parameter sIgA in saliva for the evaluations that were assumed as aim of the research. The said high variability was confirmed in a single surely healthy boy, in which sIgA were performed on saliva specimens collected for ten consecutive days, morning and evening, always at the same time (8 a.m. and p.m.). In the attempt to clarify the reason of such a variability, the intervention of psychical solicitation and emotional conditions were ipotized to modify production, mobilization and secretion of IgA generally considered and sIgA particularly.

[Clinical use of latex tests. II. Evaluation of latex tests in C-reactive protein determination]. / L'impiego clinico dei tests al lattice. II. Valutazione dei metodi al lattice per la determinazione della proteina C reattiva (PCR).

We compared the most reliable and practical laboratory methods for the quantitative determination of serum C-reactive protein that is polistyrene latex particles together with purified anti-C-reactive protein rabbit globulin, the precipitation test using anti-C-reactive protein serum and finally, radial immunodiffusion on agar-gel plates. We examined 163 serum specimens from ambulatory patients and from various hospitalized patients in Istituti Clinici di Perfezionamento of Milan (Italy). All the methods tested showed a good qualitative discrimination for serum C-reactive protein presence or absence at pathological levels. We also compared the two latex methods. In conclusion, radial immunodiffusion confirmed to be the best method for accurate C-reactive protein dosage during inflammatory and degenerative processes.

[Recent trends in the serologic diagnosis of pertussis]. / Recenti indirizzi nella diagnostica sierologica della pertosse.

Anti-whooping cough agglutinin titrations were performed in various groups of children by employing a special antigen and a microtechnique. Moderate agglutinating titers were detected in the first trimester of life and were interpreted as transmitted from the mother. Rare and moderate titers were observed in a group of children of school age, randomly selected and non institutionalized, while, on the contrary, an analogous institutionalized group showed more frequent and higher rate of antibodies. In clinically diagnosed whooping cough titers resulted high when the disease turned out to have set in more than three week earlier. Anti-whooping cough vaccination determined agglutinating titers mainly moderate and not long-lasting.