Dietary practices in pyridoxine non-responsive homocystinuria: a European survey.

BACKGROUND: Within Europe, the management of pyridoxine (B6) non-responsive homocystinuria (HCU) may vary but there is limited knowledge about treatment practice. AIM: A comparison of dietetic management practices of patients with B6 non-responsive HCU in European centres. METHODS: A cross-sectional audit by questionnaire was completed by 29 inherited metabolic disorder (IMD) centres: (14 UK, 5 Germany, 3 Netherlands, 2 Switzerland, 2 Portugal, 1 France, 1 Norway, 1 Belgium). RESULTS: 181 patients (73% >16 years of age) with HCU were identified. The majority (66%; n=119) were on dietary treatment (1-10 years, 90%; 11-16 years, 82%; and >16 years, 58%) with or without betaine and 34% (n=62) were on betaine alone. The median natural protein intake (g/day) on diet only was, by age: 1-10 years, 12 g; 11-16 years, 11 g; and >16 years, 45 g. With diet and betaine, median natural protein intake (g/day) by age was: 1-10 years, 13 g; 11-16 years, 20 g; and >16 years, 38 g. Fifty-two percent (n=15) of centres allocated natural protein by calculating methionine rather than a protein exchange system. A methionine-free l-amino acid supplement was prescribed for 86% of diet treated patients. Fifty-two percent of centres recommended cystine supplements for low plasma concentrations. Target treatment concentrations for homocystine/homocysteine (free/total) and frequency of biochemical monitoring varied. CONCLUSION: In B6 non-responsive HCU the prescription of dietary restriction by IMD centres declined with age, potentially associated with poor adherence in older patients. Inconsistencies in biochemical monitoring and treatment indicate the need for international consensus guidelines.

Safety and immunogenicity of Chiron/Biocine recombinant acellular pertussis-diphtheria-tetanus vaccine in infants and toddlers.

OBJECTIVE: To evaluate the safety and immunogenicity of the recombinant acellular pertussis-diphtheria-tetanus (aPDT) vaccine (C-aPDT, Chiron/Biocine). STUDY DESIGN: This is a randomized blinded trial evaluating the safety and immunogenicity of the recombinant aPDT vaccine (C-aPDT, Chiron/Biocine) in 2000 infant recipients compared with 498 controls who received whole cell diphtheria-pertussis-tetanus (wDPT; Connaught) vaccine at 2, 4 and 6 months of age. In addition the safety and immunogenicity of the same C-aPDT vaccine were evaluated as a booster dose in a subset of the same population when given at 15 to 18 months of age and compared with licensed Lederle aPDT vaccine. RESULTS: The C-aPDT vaccine was associated with very few local or systemic reactions when compared with wDPT. In toddlers the local and systemic side effects observed were similar after either acellular vaccine. When the immunogenicity of the C-aPDT vaccine was compared with the wDPT (Connaught) in infancy, the vaccines were equivalent for anti-diphtheria response, the wDPT developed higher anti-tetanus response and the C-aPDT vaccine was significantly more immunogenic for all other antigens tested. In toddlers the C-aPDT acellular vaccine exhibited equal or improved immunogenicity for antigens tested as compared with Lederle aPDT except for a higher anti-filamentous hemagglutinin response with the Lederle aPDT vaccine. CONCLUSION: The Chiron/Biocine aPDT vaccine offers an improved safety profile as well as improved immunogenicity when compared with a licensed wDPT product.

Pain in the well-fixed, aseptic titanium hip replacement. The role of corrosion.

We have investigated nine patients with cemented Furlong (JRI, London, UK) titanium hip replacements who presented with early pain despite a well-fixed, aseptic prosthesis. All were followed up clinically and radiologically at regular intervals. Pain was located in the thigh and was worse at night. Radiographs showed cortical hypertrophy of the femur around the tip of the stem. Eight of the nine patients subsequently required single-stage revision using an uncemented prosthesis, which relieved the pain. At revision, the pH of the tip of the stem was found to be highly acidic with macroscopic evidence of corrosion consisting of multiple layers of titanium oxides when studied by X-ray dispersive analysis. Cemented titanium implants have a potential for crevice corrosion leading to cortical hypertrophy and intractable pain.

An alternative to fixation of displaced fractures of the anterior intercondylar eminence in children.

Fractures of the anterior intercondylar eminence in children are relatively uncommon. There is considerable debate as to the best treatment of displaced fractures, but most methods described in the literature involve an open procedure combined with some form of fixation. Using human anatomical dissections, we have shown that the transverse meniscal ligament can become incarcerated within the fracture and act as a block to reduction. We describe an arthroscopic technique which requires no fixation device and report the results of its use in eight displaced fractures. This method gives reliable results and offers the advantage of less potential morbidity.

Malignant transformation in synovial chondromatosis of the knee?

Although it has been reported, malignant transformation of synovial chondromatosis is rare. We report a case of malignant transformation of synovial chondromatosis in a knee to a low-grade chondrosarcoma, which was treated with synovial excision and total knee replacement. We also present a literature review of the subject. The case illustrates that malignant transformation should be suspected in chronic cases with a sudden exacerbation of symptoms and that interpretation of histology in cartilage lesions is difficult. It also demonstrates that even when guided biopsy techniques are used, the sampling error of a needle biopsy in any large lesion is unavoidable.

Analysis of the referral pattern to a supraregional bone and soft tissue tumour service.

AIM: To investigate the sources of delay in diagnosis and determine if there was a similar diagnostic error rate as found by the Musculoskeletal Tumour Society, which subsequently altered patients' management and affected outcome. PATIENTS AND METHODS: A prospective review of 100 consecutive patients referred to our institution analysed causes for delay in referral and whether prior investigations or procedures had complicated further management. RESULTS: Patients were symptomatic for 14.8 months (range, 0-26 months) prior to consultation with their GP. A further 13.5 months (range, 0.5-120 months) elapsed before referral by the local hospital (94) or GP (6) to the bone and soft tissue service. A significant delay in referral of more than a month occurred in 72 patients. Those patients with malignant disease were symptomatic for 7.6 months (range, 0.5-11 months) prior to seeking medical advice with a further 7.5 months (range, 0-13 months) elapsing prior to onward referral at their local hospital. From the study group, 63 patients were subjected to complex imaging studies (bone scan, CT, MRI) prior to referral; 34 biopsies or surgery were performed in 34 cases by referring teams, 16 of which complicated subsequent management. CONCLUSIONS: If a high suspicion of a soft tissue or bone tumour is suspected from the history, examination and plain radiograph, then early referral to a specialist centre is recommended where relevant, high-quality investigations can be arranged in a short time leading to a planned biopsy, confirmation of diagnosis and definitive treatment at an earlier stage.

Effect of listening to Nellie the Elephant during CPR training on performance of chest compressions by lay people: randomised crossover trial.

OBJECTIVES: To determine whether listening to music during cardiopulmonary resuscitation (CPR) training increases the proportion of lay people delivering chest compressions of 100 per minute. DESIGN: Prospective randomised crossover trial. SETTING: Large UK university. PARTICIPANTS: 130 volunteers (81 men) recruited on an opportunistic basis. Exclusion criteria included age under 18, trained health professionals, and cardiopulmonary resuscitation (CPR) training within the past three months. INTERVENTIONS: Volunteers performed three sequences of one minute of continuous chest compressions on a skill meter resuscitation manikin accompanied by no music, repeated choruses of Nellie the Elephant (Nellie), and That's the Way (I like it) (TTW) according to a pre-randomised order. MAIN OUTCOME MEASURES: Rate of chest compressions delivered (primary outcome), depth of compressions, proportion of incorrect compressions, and type of error. RESULTS: Median (interquartile range) compression rates were 110 (93-119) with no music, 105 (98-107) with Nellie, and 109 (103-110) with TTW. There were significant differences within groups between Nellie v no music and Nellie v TTW (P<0.001) but not no music v TTW (P=0.055). A compression rate of between 95 and 105 was achieved with no music, Nellie, and TTW for 15/130 (12%), 42/130 (32%), and 12/130 (9%) attempts, respectively. Differences in proportions were significant for Nellie v no music and Nellie v TTW (P<0.001) but not for no music v TTW (P=0.55). Relative risk for a compression rate between 95 and 105 was 2.8 (95% confidence interval 1.66 to 4.80) for Nellie v no music, 0.8 (0.40 to 1.62) for TTW v no music, and 3.5 (1.97 to 6.33) for Nellie v TTW. The number needed to treat for listening to Nellie v no music was 5 (4 to 10)-that is, the number of cardiac arrests required during which lay responders listen to Nellie to facilitate one patient receiving compressions at the correct rate (v no music) would be between four and 10. A greater proportion of compressions were too shallow when participants listened to Nellie v no music (56% v 47%, P=0.022). CONCLUSIONS: Listening to Nellie the Elephant significantly increased the proportion of lay people delivering compression rates at close to 100 per minute. Unfortunately it also increased the proportion of compressions delivered at an inadequate depth. As current resuscitation guidelines give equal emphasis to correct rate and depth, listening to Nellie the Elephant as a learning aid during CPR training should be discontinued. Further research is required to identify music that, when played during CPR training, increases the proportion of lay responders providing chest compressions at both the correct rate and depth.

Telephone clinic follow-up following carpal tunnel decompression.

This paper investigates the feasibility of a telephone clinic follow-up service for patients undergoing carpal tunnel decompression. Six hundred and thirty patients were recruited over a 2-year period and we assessed their outcome and satisfaction level in the service, using a pre-determined questionnaire 6 weeks following surgery. The telephone clinic was overseen by a surgical care practitioner. We followed up 598 patients (93%) in total, and found 42 patients to be dissatisfied with the service (7%). These patients were referred for outpatient consultation and investigation. Most patients were satisfied with their surgical outcome and found the telephone clinic service to be convenient and effective. Cost analysis calculations estimated a potential saving of pound 45,958 over the 2-year period when compared to standard outpatient consultation. This model has been developed in our trust to follow up patients undergoing similar minor hand surgery.

Review of specialist dietitian services in patients with inherited metabolic disease in the United Kingdom.

INTRODUCTION: Dietary management forms the mainstay of treatment for many inherited metabolic diseases (IMDs) and specialist dietitians play a crucial role in the multi-disciplinary core team for these patients. Professional concerns have been expressed that the current clinical workforce is inadequate for meeting current and future service demands. The aim of this work was to describe the provision of specialist dietetics to patients with IMD as part of a national needs assessment and review. MATERIALS AND METHODS: The 24 main specialist providers and 27 specialist dietitians were surveyed by a questionnaire. A focus group of three specialist dietitians was also held to explore the roles of specialist dietitians in greater depth. RESULTS: Responses were received from all 24 specialist service providers and 63% of 27 specialist dietitians. The majority of service providers (92%) have specialist dietitians, but only eight services had more than one whole time equivalent (33%). Key roles were management of complex dietary regimens, prevention and management of metabolic crises, education, co-ordination of care, clinical audit and research. Although highly qualified, there is currently no clear formal career structure or training pathway for dietitians in IMDs. CONCLUSION: Specialist dietitians have important clinical and leadership roles in managing IMD but specialist services are thinly spread. There is a need for access to formal education, training and support programmes. The clinical workforce needs expansion to provide more comprehensive and equitable services.

Neuropsychometric outcome predictors for adults with maple syrup urine disease.

We describe 14 adult MSUD patients (3 with intermediate MSUD) with varied clinical and neuropsychometric outcomes. Age at diagnosis appears to be a predictor of IQ even in adults, while long-term blood leucine does not correlate with IQ.

A new protein substitute for adolescents and adults with maple syrup urine disease (MSUD).

AIM: The aim was to study the efficacy and acceptability of MSUD Express in adolescent and adult patients with maple syrup urine disease (MSUD). BACKGROUND: There are difficulties associated with current protein substitutes designed for adolescents and adults with MSUD. This can affect their metabolic control. MSUD Express is a new low-volume, nutritionally complete protein substitute, free from leucine, isoleucine and valine and designed specifically for older patients with MSUD. METHODS: Four patients with MSUD were included in the trial (aged 16-41 years). Product dosage was 4 x 25 g sachets per day, providing 1264 kJ and 72 g amino acids: more than adequately meeting requirements for all micronutrients. RESULTS: At the start of the study, the mean (range) of the previous eight leucine concentrations (on MSUD Aid III) was 564 micromol/L (430-817 micromol/L) and during the study (on MSUD Express) was 382 micromol/L (181-603 micromol/L). The average percentage fall in mean leucine concentrations was 32%. In patients 2, 3 and 4, low leucine levels resulted in an increase in the natural protein allowance per day. MSUD Express was rated as 'excellent' or 'good' by all patients on the basis of appearance, taste, smell and texture. All patients found the product 'very easy' to prepare and found it 'easy' or 'very easy' to take outside the home. CONCLUSION: All patients thought the preparation of MSUD Express was 'very easy'. Metabolic control (mean leucine concentrations) improved in all of the patients. In three patients this meant that an increase in the amount of natural protein in the diet was possible. All patients elected to stay on MSUD Express after the trial period. MSUD Express appears to be an effective and acceptable product, offering an alternative to current protein substitutes available for older people with MSUD.

Ketamine by continuous infusion in status asthmaticus.

A 13-year-old girl was admitted to the intensive care unit with status asthmaticus. Conventional bronchodilator therapy failed to relieve her bronchospasm. In order to try and avoid artificial ventilation, a continuous intravenous infusion of ketamine was used with success. The total dose rate was 40 micrograms/kg minute for a period of 8 hours; this was given at a decreasing rate. She regained consciousness 30 minutes after the end of the infusion and became well orientated after one hour. Ketamine is a useful drug in the intensive treatment of status asthmaticus and should be tried before a decision is taken to start mechanical ventilation.

Population differences in the frequency of the factor V Leiden variant among people with clinically symptomatic protein C deficiency.

The factor V Leiden variant, responsible for the phenomenon of activated protein C resistance, was found to be less frequent among British (0.06) and Swedish/Danish (0.15) protein C deficiency patients than previously reported in a Dutch study (0.19). In the Swedish population, a significantly increased frequency of the factor V Leiden allele was apparent in protein C deficiency patients as compared to healthy controls. However, this was not found in the British population. Coinheritance of the factor V Leiden variant is therefore unlikely to be the sole determinant of whether a person with protein C deficiency will come to clinical attention. Nevertheless, when patient data were analysed by type of protein C deficiency, it was noted that the frequency of the factor V Leiden variant was 2.8-fold higher in type II patients compared to type I patients. A possible explanation of this disparity is discussed.

Duplication of part of chromosome 17 is commonly associated with hereditary motor and sensory neuropathy type I (Charcot-Marie-Tooth disease type 1).

Hereditary motor and sensory neuropathy type I (HMSNI), also known as Charcot-Marie-Tooth disease type 1 (CMT1), has been shown to be genetically heterogeneous. A major gene maps to chromosome 17 (CMT1A). A set of loci, D17S122, D17S125, and D17S124, show tight linkage to the CMT1A locus, and a duplication of D17S122 has been detected in some families. We show that the locus D17S122 is duplicated in affected individuals from 7 informative families with HMSNI. The duplication was demonstrated either by differences in hybridization densities between two bands of a restriction fragment length polymorphism or by the presence of all three alleles. No normal individual had the duplication. A single recombinant exists between the MspI polymorphism of D17S122 and the duplicated band, suggesting that the duplication is of considerable size. Patients with HMSN type II do not show the duplication. These findings will have considerable impact on the diagnosis of chronic demyelinating neuropathies, in patients with or without similarly affected relatives.

A randomized controlled trial of early physiotherapy for high-risk infants.

The aim of this study was to investigate the hypothesis that infants at high risk of cerebral palsy would benefit from early physiotherapy. In total, 105 infants with abnormal cranial ultrasound scans were randomized at around term to early physiotherapy or standard treatment (delaying physiotherapy until abnormal physical signs became apparent). At 12 and 30 months there were clinical and objective assessments. Nine infants died and nine were lost to follow-up by 12 months when 87 infants were assessed. One other child had died and three others were lost to follow-up by 30 months when 83 children were assessed. Cerebral palsy was only accurately predicted in 45 (54%) infants. There was no difference in outcome. The difficulty of predicting cerebral palsy reliably and the heterogeneity of the condition should be borne in mind when planning treatment and assessing its efficacy.

A comparison of three procedures to assess the motor ability of 12-month-old infants with cerebral palsy.

This study compared three methods of assessing motor impairment during infancy. The 77 infants studied were considered to be at high risk of motor impairment because of abnormal neonatal cranial ultrasound scans or abnormal somatosensory responses. The children were assessed at eight and 12 months post-term by the Movement Assessment of Infants, the Griffiths locomotor development quotient and the limb-by-limb approach, and the results were compared with clinical assessment at 12 months post-term. The sensitivity of the limb-by-limb approach was highest, although its specificity was slightly lower than the other tests. It was also the easiest to perform. While giving information about the quality of movement, none of these methods is a quantitative test of movement.

A biomechanical study of four different meniscal repair systems, comparing pull-out strengths and gapping under cyclic loading.

Most studies comparing the biomechanical properties of different meniscal repair systems have simply investigated load to failure. Meniscal tissue is highly anisotropic, and far weaker under tension in the radial direction. Radially oriented loading to failure may not therefore be the most physiologically relevant in vitro test for repair of circumferential tears, and determining gapping across repair sites under cyclical loading at lower loads may be of greater importance. Using bovine menisci, vertical circumferential incisions were repaired using a simple vertical 2-0 PDS suture, Meniscal Arrow, Meniscal Fastener or T-Fix. Repairs were tested by simple loading to failure in a materials testing machine, and by cyclic loading between 5 and 10 N for 25 cycles. Initial gapping across the repairs was measured using a digital micrometer, and the increase in gapping under cyclic loading measured using a Differential Voltage Reluctance Transducer. The mean loads to failure for each of the repair groups were: sutures 72.7 N, Arrows 34.2 N, Fasteners 40.8 N and T-Fix 49.1 N. The load to failure was significantly greater with sutures than with Arrows or Fasteners. The mean gapping across the repairs for each of the repair groups after 25 loading cycles were: sutures 3.29 mm, Arrows 2.18 mm, Fasteners 3.99 mm and T-Fix 3.47 mm. The mean gapping was significantly less with Arrows than with Sutures, Fasteners or T-Fix. These results confirm that meniscal repair by suturing gives the highest load to failure, but show that Arrows give superior hold under lower loads, with the least gapping across repairs under cyclic loading of the four methods tested.

Three novel PROC gene lesions causing protein C deficiency.

Missense mutations, three of them novel (Asn210-->Val, Asn248-->Ile, Ala355-->Val), were found in the protein C (PROC) genes of 7 patients with inherited protein C deficiency associated with venous thrombosis. Comparison with the phenotypic effects of mutations in the analogous residues of factor IX causing haemophilia B and the use of molecular modelling has provided explanations as to how these lesions might alter either the structure, function or secretion of the protein C molecules encoded.

Coexistence of hereditary motor and sensory neuropathy type Ia and IgM paraproteinemic neuropathy.

A patient with minimal motor dysfunction dating from early childhood developed more rapidly progressive distal weakness and positive sensory symptoms due to peripheral neuropathy in the fourth decade of life. DNA analysis showed the partial duplication of chromosome 17p associated with hereditary motor and sensory neuropathy type Ia. In addition, the patient had an IgM paraproteinemia and the typical morphological features of IgM paraproteinemic neuropathy on nerve biopsy.

A novel missense mutation (Thr176-->Ile) at the putative hinge of the neo N-terminus of activated protein C.

We describe the detection of a novel missense mutation (Thr176-->Ile) that is located at the neo N-terminus of activated protein C. The Thr176-->Ile substitution leads to a type 1 deficiency state. Evidence is presented suggesting that this residue plays a role in pivoting the N-terminus of protein C to fold into the oxyanion hole.