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In order to further understanding of how different isolates of Burkholderia cepacia complex persist, spread and cause disease, B. cepacia-complex isolates from 60 patients attending the Cystic Fibrosis Centre of Verona, Italy, between 1997 and 2002 were analyzed. Strains were examined for species, presence of putative epidemic and virulence markers (i.e., cblA and the B. cepacia epidemic-strain marker [BCESM]), genetic relatedness and antibiotic susceptibility. Forty-five percent of patients were infected with B. cenocepacia recA subgroup B, 28% with B. cenocepacia recA subgroup A, 5% with B. multivorans and 5% with B. cepacia. No isolate carried cblA but 35% of B. cenocepacia and one of B. cepacia carried the BCESM transmissibility marker. Pulsed-field gel electrophoresis (PFGE) identified 40 types; 22 of these corresponded to sporadic isolates and 18 to clusters of identical or genetically related strains. Piperacillin, ceftazidime and piperacillin-tazobactam were the most active antibiotics (43.3, 31.1 and 35.5% of resistance, respectively). These results confirm the prevalence of B. cenocepacia in cystic fibrosis patients with rapid clinical deterioration and in those with stable cases of infection. The rates of multiple-source and cross infection were relatively low.

Azithromycin is used for the treatment of cystic fibrosis lung disease, although its mechanisms of action are not completely understood. Besides its antiinflammatory and antimicrobial activities, one possibility could be the overexpression induction of the multidrug resistance-associated protein (MRP), which could affect chloride transport, thus overcoming the ion transport defect of cystic fibrosis. Seven patients were evaluated before and after 4 weeks of azithromycin treatment (500 mg once daily). Ion transport was studied in vivo by measuring nasal potential difference (NPD). MRP mRNA expression was studied in nasal cells by an internal standard-based semiquantitative RT-PCR assay. NPD was consistent with cystic fibrosis before treatment. After azithromycin treatment, sodium transport was still impaired, whereas a significant increase in chloride conductance was observed (p = 0.03). A significant direct correlation was found between MRP mRNA expression levels and NPD chloride response after azithromycin treatment (p = 0.04, r = 0.78). In conclusion, azithromycin may induce MRP overexpression and restore chloride conductance in the airways of cystic fibrosis patients. These findings suggest a new potential role of azithromycin in the treatment of cystic fibrosis pulmonary disease, i.e. the possibility to upregulate proteins whose function may, at least in part, compensate for the basic defect of cystic fibrosis.

In September 1997, a 25-year-old Italian woman with cystic fibrosis (CF) spent 3 weeks in Thailand. In August 1998, her pulmonary function rapidly declined, with productive cough and intermittent fever. Chest x-ray films revealed diffuse, small, patchy opacities in the upper lobes. Burkholderia pseudomallei (BP) was isolated from specimens of the patient's sputum and was identified by means of 16S rDNA sequencing. The diagnosis of melioidosis was serologically confirmed. Continuous therapy with ceftazidime and co-trimoxazole and maintenance with co-trimoxazole, doxycycline, and chloramphenicol resulted in eradication of BP. We present the issue of whether patients with CF represent a population particularly at risk for melioidosis.

In patients with cystic fibrosis, infection with Pseudomonas cepacia is associated with poor outcomes. However, the epidemiology of Burkholderia cepacia is still unclear. The aim of this study was to investigate the epidemiology of Burkholderia (Pseudomonas) cepacia colonization among cystic fibrosis patients attending the Verona CF Centre, a large specialized unit to which patients from different parts of Italy are admitted. We used a genome finger-printing system to analyse the nucleotidic structure of B. cepacia isolates from 60 colonized cystic fibrosis patients. Forty-two different finger-printing patterns were identified. Thirty-two patients were colonized by individual B. cepacia strains (53.3%). The remaining 28 subjects were divided into 10 different subgroups, each exhibiting a distinct strain of B. cepacia (46.7%). Nevertheless, direct, person-to-person transmission was evident in only 10 cases (16.7%). The stability up to 12 months, of the B. cepacia colonizing strain was documented in 36 individuals. Consistent with other reports, risk of B. cepacia transmission between cystic fibrosis patients through intimacy or nosocomial contact was found in our study. However, besides low contagiousness, our data suggest that the environmental reservoir of B. cepacia outside the hospital seems to play an important role in B. cepacia infection of our cystic fibrosis population.

Genome fingerprinting by field inversion gel electrophoresis (FIGE) was utilized to typify 129 isolates of Pseudomonas cepacia (Pc) from 59 patients with cystic fibrosis (CF) and from environmental cultures in the CF ward. The aim of this study was to assess whether a segregation policy avoided colonization of CF patients by nosocomial strains and contamination of the environment by colonized individuals, whether or not an 'epidemic strain' was present in the ward and whether cross-colonization occurred in CF individuals subjected to prolonged close contact. The Pc strains of each patient remained unchanged over time; 78% of the genome finger printings (GFP) were individual, whereas the others gave rise to 9 GFP groups. A spirometer was probably contaminated by a newly colonized patient. Adequate sanitary measures and avoidance of excessive promiscuity are helpful for limiting but are unable to eliminate Pc transmission in the CF ward. Direct or indirect transmission, however seems, more frequent in CF patients in contacts outside the hospital.

To investigate the role of echo-Doppler flowmetry in evaluating patients with cystic fibrosis and portal hypertension at risk of esophageal varices, we studied 26 subjects divided in 3 groups: 9 with portal hypertension and esophageal varices, 8 with chronic liver disease without varices, and 9 without chronic liver disease. Spleen size, diameter, blood velocity, and flow rate of portal, splenic, and superior mesenteric veins were recorded. In patients without chronic liver disease Doppler measurements were repeated on 2 different days to assess intraobserver variability. Significant differences among the three groups were found for mean values of spleen size and diameters of portal, splenic, and superior mesenteric veins. Nevertheless, a considerable overlapping of individual data was observed. No differences were observed in mean hemodynamic measurements, except for blood velocity in portal vein and flow rate in splenic vein. The intraobserver variability for repeated Doppler measurements was clinically unacceptable for most of the variables studied. Echo-Doppler assessment of splanchnic flow seems to be an unreliable tool in the management of cystic fibrosis patients with portal hypertension at risk of esophageal varices.

20 CF patients, aged from 16.5 to 31.7 years, with chronic pulmonary infection due to Pseudomonas, were included in an open trial to study the efficacy of ciprofloxacin on respiratory exacerbation. Ciprofloxacin was given orally at the dose of 1500 mg/die for ten days. 16 patients concluded the entire treatment with clear clinical improvement, based on a score including 11 parameters. There has also been a significant improvement in the pulmonary function tests, and a tendency of Rx score to decrease. 4 patients interrupted the treatment on the fifth day because of clinical inefficacy. There was no increase of Pseudomonas resistance to ciprofloxacin at the end of the treatment; 30 days after no strain of pseudomonas was found resistant. We observed side-effects in 5 patients, but in no case it was necessary to discontinue the treatment. Ciprofloxacin may be considered as a good alternative to the more established antibiotic strategy in the treatment of Pseudomonas lung exacerbations in CF.

Two episodes of acute iron deficiency anemia with blood-stained sputum and symptoms of severe acute pulmonary exacerbation were observed in a child with cystic fibrosis (CF). Hemosiderin laden macrophages (siderophages) were repeatedly found in sputum and gastric juice, suggesting the coexistence of pulmonary hemosiderosis (PH). The possibility that pulmonary immune-mediated mechanisms characteristic of CF may have played a role in the development of PH is considered.