Higher skin autofluorescence in young people with Type 1 diabetes and microvascular complications

AIM

To test the hypothesis that non-invasive skin autofluorescence, a measure of advanced glycation end products, would provide a surrogate measure of long-term glycaemia and be associated with early markers of microvascular complications in adolescents with Type 1 diabetes.

METHODS

Forearm skin autofluorescence (arbitrary units) was measured in a cross-sectional study of 135 adolescents with Type 1 diabetes [mean ± sd age 15.6 ± 2.1 years, diabetes duration 8.7 ± 3.5 years, HbA_1c 72 ± 16 mmol/mol (8.7 ± 1.5%)]. Retinopathy, assessed using seven-field stereoscopic fundal photography, was defined as ≥1 microaneurysm or haemorrhage. Cardiac autonomic function was measured by standard deviation of consecutive RR intervals on a 10-min continuous electrocardiogram recording, as a measure of heart rate variability.

RESULTS

Skin autofluorescence was significantly associated with age (R² = 0.15; P < 0.001). Age- and gender-adjusted skin autofluorescence was associated with concurrent HbA_1c (R² = 0.32; P < 0.001) and HbA_1c over the previous 2.5-10 years (R² = 0.34-0.43; P < 0.002). Age- and gender-adjusted mean skin autofluorescence was higher in adolescents with retinopathy vs those without retinopathy [mean 1.38 (95% CI 1.29, 1.48) vs 1.22 (95% CI 1.17, 1.26) arbitrary units; P = 0.002]. In multivariable analysis, retinopathy was significantly associated with skin autofluorescence, adjusted for duration (R² = 0.19; P = 0.03). Cardiac autonomic dysfunction was also independently associated with skin autofluorescence (R² = 0.11; P = 0.006).

CONCLUSIONS

Higher skin autofluorescence is associated with retinopathy and cardiac autonomic dysfunction in adolescents with Type 1 diabetes. The relationship between skin autofluorescence and previous glycaemia may provide insight into metabolic memory. Longitudinal studies will determine the utility of skin autofluorescence as a non-invasive screening tool to predict future microvascular complications.

Early elevation of albumin excretion rate is associated with poor gluten-free diet adherence in young people with coeliac disease and diabetes

AIMS

There are conflicting data on microvascular complications in coexisting Type 1 diabetes and coeliac disease. We compared complications rates in youth with or without coeliac disease and examined the association between gluten-free diet adherence and complications.

METHODS

This was a comparative study of adolescents (2510 without coeliac disease, 129 with coeliac disease); 60 (47%) did not adhere to a gluten-free diet--defined as elevated anti-tissue transglutaminase or endomysial immunoglobulin A titres. Retinopathy was detected using 7-field fundal photography and albumin excretion rate by timed overnight urine collections, with early elevation defined as albumin excretion rate ≥ 7.5 μg/min. Logistic regression was used to examine the association between complications and explanatory variables, including coeliac disease vs. no coeliac disease, gluten-free diet adherence vs. non-adherence, diabetes duration and HbA1c .

RESULTS

Median age at last assessment was 16.5 years. Those with coeliac disease vs. those without were younger at diabetes diagnosis (7.1 vs. 8.6 years, P < 0.001) and had longer diabetes duration (9.3 vs. 7.2 years, P < 0.001). HbA1c was lower in those with coeliac disease vs. those without (67 vs. 70 mmol/mol, 8.3 vs. 8.6%, P = 0.04) and adherence to a gluten-free diet vs. non-adherence (66 vs. 72 mmol/mol, 8.2 vs. 8.7%, P = 0.003). There were no differences in complication rates between those with coeliac disease vs. those without (retinopathy 22 vs. 23%, elevated albumin excretion rate 31 vs. 28%). Non-adherence to a gluten-free diet was associated with elevated albumin excretion rate (40 vs. 23%, P = 0.04). In multivariable logistic regression, elevated albumin excretion rate was associated with non-adherence to a gluten-free diet (odds ratio 2.37, 95% CI 1.04-5.40, P = 0.04) and diabetes duration (odds ratio 1.13, 95% CI 1.02-1.25, P = 0.03), but not HbA1c .

CONCLUSIONS

While glycaemic control is better in patients with coeliac disease, non-adherence to a gluten-free diet is associated with elevated albumin excretion rate. The possible protection of a gluten-free diet on complications warrants further investigation.

Space flight alters bacterial gene expression and virulence and reveals a role for global regulator Hfq

A comprehensive analysis of both the molecular genetic and phenotypic responses of any organism to the space flight environment has never been accomplished because of significant technological and logistical hurdles. Moreover, the effects of space flight on microbial pathogenicity and associated infectious disease risks have not been studied. The bacterial pathogen Salmonella typhimurium was grown aboard Space Shuttle mission STS-115 and compared with identical ground control cultures. Global microarray and proteomic analyses revealed that 167 transcripts and 73 proteins changed expression with the conserved RNA-binding protein Hfq identified as a likely global regulator involved in the response to this environment. Hfq involvement was confirmed with a ground-based microgravity culture model. Space flight samples exhibited enhanced virulence in a murine infection model and extracellular matrix accumulation consistent with a biofilm. Strategies to target Hfq and related regulators could potentially decrease infectious disease risks during space flight missions and provide novel therapeutic options on Earth.

Secondary glaucoma after paediatric cataract surgery

AIM

To determine the prevalence and risk factors associated with secondary glaucoma postcongenital cataract surgery.

METHODS

All children diagnosed as having congenital cataracts in a major children's hospital between 1985 and 2005 were included in a retrospective case series. Medical records of 423 eyes among 283 patients who underwent cataract surgery with or without intraocular lens implantation at age </=16 for congenital cataract were reviewed. The main outcome measure was presence or absence of secondary glaucoma and time to glaucoma postsurgery. The following risk factors were evaluated: age at cataract surgery, presence of systemic anomalies, microcornea, persistent hyperplastic primary vitreous (PHPV), primary capsulotomy/anterior vitrectomy, primary intraocular lens implantation, secondary membrane surgery and duration of postoperative observation.

RESULTS

The statistical methods were the use of Kaplan-Meier survival analysis and Multivariate Cox hazards regression analysis. The mean follow-up was 6.3 (SD 5.0) years (median 4.6 years; range 0.5 to 20.3 years). Glaucoma developed in 36 of 234 patients (15.4%). Multivariate Cox proportional hazards regression analysis identified age less than 9 months at time of surgery (RR 2.9, 95% CI 1.3 to 7.7; p = 0.03), microcornea (RR 3.7, 95% CI 2.0 to 7.0; p<0.001), and follow-up time as important predictors of glaucoma. PHPV (RR 1.4, 95% CI 0.7 to 2.7; p = 0.41) and primary posterior capsulotomy/anterior vitrectomy (RR 2.2, 95% CI 0.9 to 5.5; p = 0.17) were not significantly associated with secondary glaucoma in the multivariate model. The mean time to glaucoma after congenital cataract surgery was 4.9 years (range 2 weeks to 16.8 years).

CONCLUSION

Secondary glaucoma is an important sequela in patients who undergo surgery for congenital cataracts. It is imperative that these patients get lifelong surveillance, as glaucoma can occur years after the initial operation.

Genome complexity in acute lymphoblastic leukemia is revealed by array-based comparative genomic hybridization

Chromosomal abnormalities are important for the classification and risk stratification of patients with acute lymphoblastic leukemia (ALL). However, approximately 30% of childhood and 50% of adult patients lack abnormalities with clinical relevance. Here, we describe the use of array-based comparative genomic hybridization (aCGH) to identify copy number alterations (CNA) in 58 ALL patients. CNA were identified in 83% of cases, and most frequently involved chromosomes 21 (n=42), 9 (n=21), 6 (n=16), 12 (n=11), 15 (n=11), 8 (n=10) and 17 (n=10). Deletions of 6q (del(6q)) were heterogeneous in size, in agreement with previous data, demonstrating the sensitivity of aCGH to measure CNA. Although 9p deletions showed considerable variability in both the extent and location, all encompassed the CDKN2A locus. Six patients showed del(12p), with a common region encompassing the ETV6 gene. Complex CNA were observed involving chromosomes 6 (n=2), 15 (n=2) and 21 (n=11) with multiple regions of loss and gain along each chromosome. Chromosome 21 CNA shared a common region of gain, with associated subtelomeric deletions. Other recurrent findings included dim(13q), dim(16q) and enh(17q). This is the first report of genome-wide detection of CNA in ALL patients using aCGH, and it has demonstrated a higher level of karyotype complexity than anticipated from conventional cytogenetic analysis.

Gain of 1q is associated with adverse outcome in favorable histology Wilms' tumors

Although several genes/genetic loci involved in the etiology of Wilms' tumor have been identified, little is known of the molecular changes associated with relapse. We therefore undertook an analysis by comparative genomic hybridization (CGH) of 58 tumor samples of favorable histology Wilms' tumor taken at initial diagnosis and/or relapse. Tumors with anaplastic histology were excluded as this is known to be associated with p53 mutation and a poor prognosis. A control group of 21 Wilms' tumors that did not relapse was also analyzed. The overall frequency of gains or losses of genetic material detected by CGH was similar in both groups (77% in relapsing tumors and 70% in the nonrelapse group) as was the median number of changes per tumor (relapse group: n = 4, range, 1 to 19; nonrelapse group: n = 3, range, 1 to 8). However, gain of 1q was significantly more frequent in the relapse series [27 of 46 (59%) versus 5 of 21 (24%), P: = 0.019]. In 12 matched tumor pairs, the CGH profiles, including 1q gain, were similar at diagnosis and relapse, with little evidence for further copy number changes being involved in clonal evolution. The results suggest that 1q gain at diagnosis could be used to identify patients with favorable histology Wilms' tumor at increased risk of relapse who might benefit from early treatment intensification.

The effect of prepubertal diabetes duration on diabetes. Microvascular complications in early and late adolescence

OBJECTIVE

To define the significance of prepubertal diabetes duration in the development of diabetic microvascular complications in adolescents.

RESEARCH DESIGN AND METHODS

Study A compares complications in 38 prepubertal (PreP) and 140 pubertal (Pub) subjects of the same age (10-14 years) and diabetes duration (3-12 years) to determine if the absence of puberty itself confers a lower risk of complications. Study B examines the importance of prepubertal and pubertal diabetes duration in 193 older adolescents (ages 15-22 years) with prepubertal onset of diabetes. Retinopathy status was assessed using stereoscopic fundus photography of seven fields per eye. Albumin excretion rate (AER) was assessed by three consecutive overnight urine collections, using a polyclonal radioimmunoassay.

RESULTS

In study A, there were no significant differences between the PreP and Pub groups for retinopathy (27 vs. 29%, P = 0.8) or differences in elevated AER (17 vs. 31%, P = 0.1). In study B, longer prepubertal diabetes duration improved the prediction for retinopathy over postpubertal duration alone (P < 0.0005). No relationship with duration was found for elevated AER (> 7.5, > 15, and > 30 micrograms/min).

CONCLUSIONS

Prepubertal subjects with diabetes did not have less retinopathy or elevated albumin excretion compared with pubertal subjects of the same age. Prepubertal diabetes duration is significantly related to the presence of retinopathy in adolescents.

Serologic and DNA follow-up data from HBsAg-positive patients treated with orthotopic liver transplantation

Fifteen hepatitis B surface antigen (HBsAg) positive patients treated with orthotopic liver transplantation were studied to determine whether any clinical, serologic, or histologic data were predictive for recurrent hepatitis B infection leading to graft failure. Six patients died early, one due to primary graft nonfunction and the remaining five due to septic complications. There were nine patients surviving longer than two months, eight of whom are alive at a mean follow-up of 556 days. HBsAg and hepatitis B core antibody (anti-HBc) reappeared in the sera of all survivors after a variable transient period of clearance. One patient died 3 months posttransplant of fungal sepsis and was found to have histologic evidence for recurrent hepatitis and positive immunoperoxidase staining postmortem. The remaining eight survivors are home and clinically well, with no histologic evidence of hepatitis. Seven of these eight patients have hepatitis B viral DNA in their sera. We conclude that while there is a high early mortality, usually from sepsis, none of the serologic, histologic, or DNA data analyzed can be used to predict graft loss from recurrent hepatitis. No grafts have been lost due to recurrent hepatitis B in this series, and therefore we believe that HBsAg positive patients should not be excluded from transplantation.

Bilateral blinding uveitis in a child after secondary intraocular lens implantation for unilateral congenital cataract

A 3-year-old boy underwent secondary implantation of an iris supported intraocular lens following extraction of a unilateral congenital cataract. Eight months later, he developed a bilateral plastic uveitis which, in spite of intensive medical treatment, resulted in NPL (no perception of light) in the implanted eye and 2/60 vision in the fellow eye. Sympathetic ophthalmia possibly played a role in the pathogenesis of the uveitis.

Postoperative endophthalmitis in children following cataract surgery

Three children developed endophthalmitis after cataract surgery. Each had signs and symptoms of either nasolacrimal duct obstruction or upper respiratory infection at the time of surgery. The causative organisms were Staphylococcus aureus, Staphylococcus epidermidis, and Streptococcus pneumoniae. Final visual acuities were 6/24, LP, and NLP, respectively. Endophthalmitis after cataract surgery in infants has never been reported. These three cases drawn from two pediatric ophthalmology practices represent an incidence of postoperative endophthalmitis of 0.45%. Although this incidence report is potentially spurious, it indicates that postoperative endophthalmitis is a very real threat in infants. We recommend a thorough systems review and exam of upper airways and lacrimal system before undertaking intraocular surgery in young children. We also caution against simultaneous bilateral surgery.

Hemifacial spasm in infancy

Three infants presented with the onset of hemifacial spasm after birth and at the age of 10 months. One patient was found to have occlusion of the straight sinus and large collateral veins at the base of the brain, presumably due to venous sinus thrombosis, supporting the concept of vascular compression of the facial nerve at its exit from the brain stem as a mechanism for the production of hemifacial spasm. The other patients each had an intrinsic mass compressing the fourth ventricle, located in the lower pons and extending into the cerebellar vermis and right cerebellar peduncle in one; in the other patient, the mass involved the cerebellar vermis and right middle cerebellar peduncle alone. These patients widen the etiologic spectrum of the syndrome and show that serious intracranial diseases may underlie hemifacial spasm in infancy.

Complete cryptophthalmos: case report with normal flash-VEP and ERG

We report an infant with bilateral complete cryptophthalmos as part of Fraser Syndrome. Clinical examination and recordings of the electroretinogram and flash visual evoked potential showed a functional visual pathway at retinal and post-retinal levels. Anatomical considerations and the possible complications of surgery made reconstruction of the lids and palpebral fissures inappropriate.

Lens surgery in infancy and childhood

The medical records of 224 children who had lens surgery performed at the Hospital for Sick Children during the 10-year period 1978-88 were reviewed. There were 12 children with ectopia lentis; these patients achieved a mean postoperative acuity of 0.68 (6/8.8), and no operative or postoperative complications were noted. Two hundred and twelve children had lens surgery for cataracts or for retrolental abnormalities with a clear lens. Children with bilateral congenital cataracts achieved a mean acuity in the better eye of 0.32 (6/18). In a series of carefully controlled unilateral congenital cataracts the visual results were poor. The postoperative complication rate for cataract and clear lens surgery was 4.6%. Because visual results are probably better with early surgery we emphasise that every newborn baby should be tested for media opacities.

De novo deletion of Xp22.2-pter in a female with linear skin lesions of the face and neck, microphthalmia, and anterior chamber eye anomalies

A female infant is described with an unusual combination of eye and skin findings. Raw linear skin lesions on the face and neck were present at birth, healing to leave pigmented streaks. In addition she had left sided microphthalmia and bilateral sclerocornea. Chromosome analysis showed a terminal deletion of the short arm of the X chromosome (Xp22.2--pter). Clinical findings were similar to three previously described children with translocations involving Xp22.3. The condition probably represents a new syndrome distinct from incontinentia pigmenti and Goltz syndrome.

Multiple tandem 18-kb sequences clustered in the region of the acute promyelocytic leukemia breakpoint on chromosome 17

This paper describes the cloning of an 18-kb sequence present in approximately 30 copies on chromosome 17. Most of these are clustered in the region of the breakpoint associated with acute promyelocytic leukemia (APL). These copies map both above and below the breakpoint, and pulsed field gel analysis indicates that the majority of these sequences lie within a region of approximately 2 megabases. The organization of these sequences appears to be that of large imperfect palindromes.

Assignment of complement components C4 binding protein (C4BP) and factor H (FH) to human chromosome 1q, using cDNA probes

Using cDNA probes for Factor H (FH) and C4 binding protein (C4BP) on a panel of somatic cell hybrids, we show that both of these genes map to the long arm of chromosome 1.

Regional localization of CD18, the beta-subunit of the cell surface adhesion molecule LFA-1, on human chromosome 21 by in situ hybridization

The gene coding for the beta-subunit of the cell surface adhesion glycoprotein LFA-1 has been localized to the tip of the long arm of chromosome 21 at 21q22.1-qter.