Microalbuminuria as a screening tool in cystic fibrosis-related diabetes.

The improving longevity of cystic fibrosis (CF) subjects has resulted in an increased prevalence and duration of cystic fibrosis-related diabetes (CFRD). Microvascular complications were reported in CFRD. Microalbuminuria is well-established as a sensitive indicator of progression to diabetic nephropathy in non-CF diabetes, but confounding factors may make it less sensitive for CF subjects. We performed a cross-sectional study to look for the presence of microalbuminuria in samples from 40 CF subjects (34 without diabetes; CFND) attending the Exeter CF Clinic, compared with 43 nondiabetic, non-CF controls. The albumin-creatinine ratio (ACR) was raised in CF subjects both with (P < 0.001) and without (P < 0.0001) diabetes compared to controls. This reflected an increase in urinary albumin and a reduction in urinary creatinine in CF subjects. In single samples, microalbuminuria was present in 66.7%, 32.4%, and 15.4% of subjects in CFRD, CFND, and control groups. Repeat samples showed that 12% of CFND subjects and 17% of CFRD subjects met the criteria for a diagnosis of persistent microalbuminuria. In conclusion, CF subjects, even when not diabetic, have increased urinary albumin excretion due to chronic infection, and reduced urinary creatinine excretion due to low muscle mass. This results in subjects, who are not developing diabetic nephropathy, meeting the conventional criteria for microalbuminuria. We feel that further studies are required to clarify whether this measure is a useful tool to predict progression to diabetic nephropathy in subjects with CFRD.

Sites of implantation for central venous access devices (ports): a study of the experiences and preferences of patients.

OBJECTIVE: To obtain information which might guide vascular specialists and their patients in the choice of site for implantation of central venous access devices (CVADs). DESIGN: Questionnaire study. METHODS: Questionnaires were sent to 69 patients with cystic fibrosis and 54 (78%) responded (39 females: age 5-63, median 24 years). They had received a total of 79 CVADs placed in the upper chest (60), lower chest (13), thigh (3) and arm (3). Only 46% patients had been offered a choice of site. RESULTS: Questions about 14 specific areas of disability or concern found problems most frequently with discomfort (54%), wearing a seatbelt (51%), cosmetic appearance (44%), scarring (44%), choice of clothing (42%) and lying in bed or sleeping (42%). There were no significant differences between upper and lower chest CVADs. Patients with upper chest CVADs seldom had any problems with use of their arm (12%). 81% CVADs could not be accessed by the patients, and in 39% of these cases patients would have liked to do so. CONCLUSIONS: Many patients complain of few problems with their CVADs, regardless of site, but half have some persistent discomfort. Cosmetic considerations frequently cause concern and patients should be given choice in the site of their CVADs.

Zebrafish colourless encodes sox10 and specifies non-ectomesenchymal neural crest fates.

Waardenburg-Shah syndrome combines the reduced enteric nervous system characteristic of Hirschsprung's disease with reduced pigment cell number, although the cell biological basis of the disease is unclear. We have analysed a zebrafish Waardenburg-Shah syndrome model. We show that the colourless gene encodes a sox10 homologue, identify sox10 lesions in mutant alleles and rescue the mutant phenotype by ectopic sox10 expression. Using iontophoretic labelling of neural crest cells, we demonstrate that colourless mutant neural crest cells form ectomesenchymal fates. By contrast, neural crest cells which in wild types form non-ectomesenchymal fates generally fail to migrate and do not overtly differentiate. These cells die by apoptosis between 35 and 45 hours post fertilisation. We provide evidence that melanophore defects in colourless mutants can be largely explained by disruption of nacre/mitf expression. We propose that all defects of affected crest derivatives are consistent with a primary role for colourless/sox10 in specification of non-ectomesenchymal crest derivatives. This suggests a novel mechanism for the aetiology of Waardenburg-Shah syndrome in which affected neural crest derivatives fail to be generated from the neural crest.