Pseudomonas aeruginosa in the home environment of newly infected cystic fibrosis patients.

The source of acquisition of Pseudomonas aeruginosa in cystic fibrosis (CF) patients remains unknown. Patient-to-patient transmission has been well documented but the role of the environment as a source of initial infection is as yet unclear. In the present study, the origin of the first P. aeruginosa isolate in CF patients was investigated by comparing the P. aeruginosa genotype(s) from newly infected patients with genotypes of P. aeruginosa isolates from the home environment and from other patients from the same CF centre. A total of 50 newly infected patients were studied. P. aeruginosa could be cultured from 5.9% of the environmental samples, corresponding to 18 patients. For nine of these, the genotype of the environmental P. aeruginosa isolate was identical to the patient's isolate. In total, 72% of the environmental P. aeruginosa isolates were encountered in the bathroom. Patient-to-patient transmission within the CF centre could not be ruled out for three patients. In summary, a low prevalence of Pseudomonas aeruginosa was found in the home environment of the newly infected cystic fibrosis patients. The bathroom should be targeted in any preventive cleaning procedures. An environmental source of the new infection could not be ruled out in nine patients.

Survey of Pseudomonas aeruginosa genotypes in colonised cystic fibrosis patients.

The current authors aimed to examine whether cystic fibrosis (CF) patients in Belgium shared Pseudomonas aeruginosa genotypes and to compare the genotypes of isolates from the same patients during two consecutive years. A Belgian databank of the P. aeruginosa genotypes of all colonised CF patients was created. Sputum samples from a total of 276 P. aeruginosa colonised patients during 2003, and from a subgroup of 95 patients in 2004, were analysed. Patients were asked about any social contact between each other by questionnaire. All P. aeruginosa isolates exhibiting different colonial morphology on McConkey agar were first genotyped using arbitrarily primed PCR, whereafter single representatives of each randomly amplified polymorphic DNA-type were further genotyped by fluorescent amplified fragment length polymorphism analysis. In the 213 patients from whom P. aeruginosa could be cultured (resulting in 910 isolates), a total of 163 genotypes were found. The majority (75%) of patients harboured only one genotype. In most of the limited number of clusters, previous contacts between patients could be suspected. In 80% of the patients studied during both years, P. aeruginosa genotype remained unchanged. In conclusion, most colonised cystic fibrosis patients harbour only one Pseudomonas aeruginosa genotype, despite showing different colonial morphotypes. The number of clusters is limited, and most patients seem to retain the same genotypic strain during both years.

[Exercise in children with chronic disease]. / Pratique sportive et pathologies pédiatriques.

Regular physical exercise is gaining acceptance as a prescription for the prevention, management and rehabilitation of diseases occurring in the pediatric and adolescent age group. Exercise is generally used to increase the physical capabilities of these young patients, but, at times, it can directly influence the evolution of the condition. However, in children with chronic diseases, enhanced physical activity can also be deleterious. A well structured exercise program should be implemented. This paper will focus on the role of exercise in different diseases including cardiovascular, pulmonary, neuromuscular disease, diabetes and obesity.

Gas exchange and heart rate kinetics during binary sequence exercise in cystic fibrosis.

MATERIAL AND METHODS: Gas exchange and heart rate (HR) kinetics were investigated in 20 patients with cystic fibrosis (CF) by using a pseudorandom binary sequence (PRBS)-technique. Electrocardiogram was continuously recorded, and VO2, VCO2 and ventilation/min (VE) responses to a multifrequent input signal were measured by means of breath-by-breath analysis. Lag time and peak value in the time-domain, and amplitude ratios in the frequency-domain were calculated to characterize the crosscorrelation functions between input and responses, and compared to normal ranges. RESULTS: Time and frequency domain parameters are abnormal for VO2, VCO2 and VE responses in moderately and severely ill patients, and for the HR response only in severely ill patients. Correlations are shown between those parameters, the severity of the illness evaluated by the Shwachman score and the level of impairment of the pulmonary function. CONCLUSION: The PRBS-technique is a useful tool to investigate the gas exchange and HR kinetics in CF patients, that offers many advantages: (1) no explicit mathematical models are assumed, (2) it is a walking test that may be used even in very young or severely ill patients, and (3) it challenges the ability to adapt to non-steady state exercise and is therefore representative for daily activities.

Usefulness of random fecal alpha 1-antitrypsin and chymotrypsin determinations in children.

Random fecal chymotrypsin activity and fecal alpha 1-antitrypsin (FA-1-AT) concentrations were determined in 11 children with cystic fibrosis, 5 children with Crohn's disease, 9 children with chronic aspecific diarrhea, 85 children with acute gastroenteritis, and 54 control children. Cystic fibrosis patients showed only very low fecal chymotrypsin values that did not overlap with values obtained in patients with either acute or chronic diarrhea. When compared with our control group, a significant increase of FA-1-AT concentrations was found only in children with Crohn's disease. Normal values were found in all patients with either chronic aspecific diarrhea or cystic fibrosis, while 12 of 85 children with acute gastroenteritis showed FA-1-AT concentrations above the 95th percentile of control children. We conclude that diarrhea (either acute or chronic) does not significantly decrease the clinical usefulness of fecal chymotrypsin activity measurements in the diagnosis of pancreatic insufficiency, while acute (gastroenteritis) but not chronic (chronic aspecific diarrhea, cystic fibrosis) diarrhea can give rise to protein losing and FA-1-AT concentrations similar to those found in Crohn's disease.

Lactulose-rhamnose intestinal permeability in children with cystic fibrosis.

The lactulose-rhamnose intestinal permeability test was performed in 10 cystic fibrosis (CF) children. Urine was collected for 5 h after oral intake of the test solution. A single thin-layer chromatography followed by densitometry was used for the measurement of lactulose and rhamnose concentrations in the urine specimens. The excretion of each molecule was expressed as the percentage of the orally administered dose excreted and the lactulose-rhamnose ratio was the ratio of the percentage quantities of each probe molecule excreted. The mean lactulose-rhamnose excretion ratio in CF patients and controls was 0.16 and 0.038, respectively (p less than 0.001). The mean 5-h lactulose excretion was 2% and 0.28% in CF patients and control subjects, respectively (p less than 0.001). The mean 5-h rhamnose excretion was 12.8% and 7.6% in CF patients and control subjects (p less than 0.05). We conclude that CF patients have an increased intestinal permeability to lactulose and rhamnose. Further studies are needed in order to elucidate the mechanisms involved as well as the eventual nutritional implications.

Intestinal permeability to [51Cr]EDTA in children with cystic fibrosis.

Intestinal permeability was investigated in 14 children with cystic fibrosis making use of [51Cr]EDTA as probe molecule. Ten normal young adults and 11 children served as controls. After oral administration of [51Cr]EDTA, 24 h urine was collected. Urinary radioactivity was calculated and results expressed as percentage of oral dose excreted in 24 h urine. Mean and SEM were as follows: 2.51 +/- 0.21, 2.35 +/- 0.24, and 13.19 +/- 1.72 for control children, normal adults, and cystic fibrosis patients, respectively. The permeability differences between cystic fibrosis patients and either control children or control adults are significant (p less than 0.001).