Displaced scaphoid waist fractures: the use of a week 4 CT scan to predict the likelihood of union with nonoperative treatment

This study assessed whether nonunion of displaced scaphoid waist fractures with nonoperative treatment could be predicted from 4 week CT scans. Thirty-one patients with unilateral displaced scaphoid waist fractures and adequate follow-up were included. CT scans in the longitudinal axis of the scaphoid with sagittal and coronal slices were done 4 weeks after the index injury. The effects of fracture gap, sclerosis and bone resorption on union were assessed. Fracture union was observed in all 13 displaced fractures with a < 2 mm gap, four of the seven with a gap of 2-3 mm and only four of the 11 with a gap > 3 mm (p = 0.01). Bone resorption involving more than 50% of the fracture cross-section was also associated with nonunion, but sclerosis was not.

Valproate and risk of fracture in Rett syndrome

OBJECTIVES

Some associations between antiepileptic drugs (AEDs) and fracture risk have been reported in the general population. This study investigated the relationships between fracture risk and commonly used AEDs in Rett syndrome, a genetic disorder associated with intellectual and physical disability.

STUDY DESIGN

Cases (n=233) were sourced from the population-based Australian Rett Syndrome Database and longitudinal data were used. The Cox proportional hazard model was used to analyse relationships between fracture and prescribed AEDs, mobility, epilepsy diagnosis and genotype.

RESULTS

After controlling for mobility, epilepsy diagnosis and genotype, use of valproate increased the risk of fracture threefold after at least 1 year (HR 3.56; 95% CI 1.85 to 6.82) and after 2 or more years (HR 3.02; 95% CI 1.90 to 4.80). There was a lesser increased risk (HR 1.99; 95% CI 0.99 to 4.02) with lamotrigine in the first year of use but not for subsequent years of use. Carbamazepine slightly decreased the risk (HR 0.60; 95% CI 0.35 to 1.02) after 2 or more years of use.

CONCLUSIONS

The effect of valproate on bone health should be considered when managing epilepsy in Rett syndrome. Multiple mechanisms could be contributing to this effect.

Updating the profile of C-terminal MECP2 deletions in Rett syndrome

OBJECTIVES

This study aimed to compare the phenotype of Rett syndrome cases with C-terminal deletions to that of cases with different MECP2 mutations and to examine the phenotypic variation within C-terminal deletions.

METHODS

Cases were selected from InterRett, an international database and from the population-based Australian Rett Syndrome Database. Cases (n=832) were included if they had a pathogenic MECP2 mutation in which the nature of the amino acid change was known. Three severity scale systems were used, and individual aspects of the phenotype were also compared.

RESULTS

Lower severity was associated with C-terminal deletions (n=79) compared to all other MECP2 mutations (e.g. Pineda scale C-terminals mean 15.0 (95% CI 14.0-16.0) vs 16.2 (15.9-16.5). Cases with C-terminal deletions were more likely to have a normal head circumference (odds ratio 3.22, 95% CI 1.53 - 6.79) and weight (odds ratio 2.97, 95% CI 1.25-5.76). Onset of stereotypies tended to be later (median age 2.5 years vs 2 years, p<0.001 from survival analysis), and age of learning to walk tended to be earlier (median age 1.6 years vs 2 years, p=0.002 from survival analysis). Those with C-terminal deletions occurring later in the region had lower average severity scores than those occurring earlier in the region.

CONCLUSION

In terms of overall severity C-terminal deletion cases would appear to be in the middle of the range. In terms of individual aspects of phenotype growth and ability to ambulate appear to be particular strengths. By pooling data internationally this study has achieved the case numbers to provide a phenotypic profile of C-terminal deletions in Rett syndrome.

The common BDNF polymorphism may be a modifier of disease severity in Rett syndrome

BACKGROUND

Rett syndrome (RTT) is caused by mutations in the transcriptional repressor methyl CpG-binding protein 2 (MECP2). Brain-derived neurotrophic factor (BDNF) is a neurotrophic factor playing a major role in neuronal survival, neurogenesis, and plasticity, and it has been shown that BDNF expression is regulated by MeCP2 through a complex interaction. A common polymorphism of BDNF (Val66Met [p.V66M]) has been found to correlate with severity and course of several neuropsychiatric disorders.

METHODS

We examined the association between disease severity score, assessed by the modified Percy score, and BDNF polymorphism, using regression methods, in 125 mutation-positive patients with RTT from the Australian Rett Syndrome Database and an Israeli cohort.

RESULTS

Those who were heterozygous (Val/Met) had slightly more severe disease than those who were homozygous for the wild-type (Val/Val) BDNF polymorphism (increased severity score 2.1, p = 0.09). In those with p.R168X, a commonly occurring MECP2 mutation in RTT, there was a 6-point increase in severity score for those who were heterozygous for the BDNF polymorphism, both unadjusted (p = 0.02) and adjusted for age (p = 0.03). Individuals with the p.R168X mutation and heterozygous for the BDNF polymorphism were also at an increased risk of seizure onset (hazard ratio 5.3, 95% confidence interval 1.6-17.7) compared with those homozygous for the wild-type BDNF allele.

CONCLUSIONS

In addition to mutation type and degree of X-chromosome skewing, the common brain-derived neurotrophic factor (BDNF) polymorphism appears to be another genetic modifier of Rett syndrome (RTT) severity. This suggests that BDNF function may play a significant role in the pathogenesis of RTT.

Investigating genotype-phenotype relationships in Rett syndrome using an international data set

BACKGROUND

Rett syndrome is an uncommon neurodevelopmental disorder with an incidence of 1:9,000 live female births. The principal genetic cause was first reported in 1999 when the association with mutations in the methyl-CpG-binding protein 2 (or MECP2) gene was identified. This study uses data from a large international database, InterRett, to examine genotype-phenotype relationships and compares these with previous findings in a population-based cohort.

METHOD

The data set for these analyses was derived from a subset of InterRett cases with subject information collected from the family, the clinician, or both. Individual phenotypic characteristics and clinical severity using three scales were compared among those with eight known recurrent pathogenic MECP2 mutations as well as those with C-terminal deletions (n = 272).

RESULTS

Overall, p.R270X and p.R255X were the most severe and p.R133C and p.R294X were the mildest mutations. Significant differences by mutation were seen for individual phenotypic characteristics such as hand use, ambulation, and language.

CONCLUSIONS

This multicenter investigation into the phenotypic correlates of MECP2 mutations in Rett syndrome has provided a greater depth of understanding than hitherto available about the specific phenotypic characteristics associated with commonly occurring mutations. Although the modifying influence of X inactivation on clinical severity could not be included in the analysis, the findings confirm clear genotype-phenotype relationships in Rett syndrome and show the benefits of collaboration crucial to effective research in rare disorders.

Dupuytren’s disease in an infant

Dupuytren’s disease of the hand has only been rarely reported in children and is rarer still in infants. We report a case in a six-month-old infant who required surgery when aged ten months. Histology confirmed the diagnosis of Dupuytren’s disease.

Dupuytren's disease in an infant

Dupuytren's disease of the hand has only been rarely reported in children and is rarer still in infants. We report a case in a six-month-old infant who required surgery when aged ten months. Histology confirmed the diagnosis of Dupuytren's disease.

Cast wedging for orthopaedic surgeons!

The use of cast wedging is decreasing. Previous described methods are complicated, using geometric calculations that can be confusing and difficult to remember. We describe a very simple method we use routinely that involves a pen, a piece of paper and a pair of scissors only, without the need to calculate or measure angles.

Patients' case-notes: look but don't touch

The purpose of this study was to ascertain whether viable bacteria could be cultured from patients' case-notes. Two hundred and twenty-eight current inpatients' notes were randomly sampled using contact plates to determine total viable counts, Gram-positive organisms, Gram-negative organisms and methicillin-resistant Staphylococcus aureus (MRSA). Bacteria were grown from 227. Most were 'environmental', however, nine notes grew S. aureus. No Gram-negative bacteria or MRSA were isolated. These results show that potentially pathogenic bacteria can be found on case notes and could act as a source of transmission or cross-infection to patients. We recommend that handwashing should occur after handling case notes before patient contact.

Residential and nursing home care of elderly people with cognitive impairment: prevalence, mortality and costs

Cognitive impairment among residents has considerable resource implications for both individuals and those responsible for publicly funded care. Two linked surveys were carried out in England: (1) a longitudinal study followed 2500 admissions to publicly funded care up to 42 months after admission; and (2) a cross-sectional survey of 618 homes collected information about 11,900 residents. Information was collected about cognitive impairment using the Minimum Data Set Cognitive Performance Scale. Cognitive impairment was associated with source of funding and type of home. Although level of cognitive impairment has some effect, fees and costs were most influenced by type of home. At the same level of impairment, self-funded residents were more likely to be located in relatively low-cost settings than publicly funded residents. In independent homes fees were lower for publicly funded than for self-funded residents. Overall median length of stay of publicly funded admissions was 18 months. For the most part length of stay was not associated with level of cognitive impairment on admission. It is concluded that more information is needed about the effect of quality of care on people with cognitive impairment in different settings. If the same quality of care can be achieved in residential and nursing homes, the evidence would suggest that changes in placement policies could result in potential savings to the public purse.