Their usual formula was given on day −7 to 0 and 8 to 21; MCTF was given day 0-7. Blood samples were taken day −7, 0, 2, 7 and 14 (analytes included liver function tests, creatine kinase, glucose, acyl carnitines, free fatty acids and 3-hydroxybutyrates). ECG was monitored day 0 and 7. Results: There was no significant difference in biochemical control or ECG, and no child developed symptoms of metabolic decompensation on MCTF. Tolerance was good, although one subject developed constipation. MCTF was well accepted. There was consensus among clinics to eliminate dairy-based foods and ingredients, but a variation in restriction of more minor sources of galactose. Thirty-three percent of clinics routinely eliminate fruits and vegetables, such as tomatoes and blueberries, with a free galactose content >20 mg/100 g of food. Twenty percent restrict these foods only during infancy and early childhood, but allow them for older individuals. Another 30% of clinics do not restrict any fruits and vegetables. Similar variation in clinic policies was found for other foods and ingredients. Policies also vary regarding use of liquid soy-based formulas containing carrageenan and use of elemental galactose-free formulas for infants with slowly decreasing red cell galactose-1-phosphate concentrations. For infants with the Duarte variant, 43% of clinics treat with a soy formula for the first year while 27% of clinics do not treat this form of galactosemia. Results from this survey demonstrate a need for evidence-based recommendations to better standardize treatment for this disorder. Background: Pyruvate dehydrogenase complex deficiency (PDHCD) comprises a range of phenotypes and may be treated with ketogenic diet. We present 4 patients with enzymatically confirmed PDHCD treated with a modified ketogenic diet similar to the modified Atkins diet. In all families there were barriers of language, geographical distance and/or social circumstances to hospital admission and/or diet calculations, required by the traditional ketogenic diet. Case Reports: Three patients (3-5 years) commenced the diet at home with some or all of their usual milk drinks substituted with Ketocal.. Patient 1 was admitted to ensure safety of enteral feeding and parental understanding; 2 families made gradual changes at home to their child's usual eating plan whilst testing urinary ketones twice daily. All were advised on management strategies should urinary ketones exceed 16 mmol/ l. All patients are maintaining urinary ketones between 1.5-8 mmol/l and report clinical improvement (less irritability, improved motor function, less hospital admissions). A 17 year old previously on a high fat diet, commenced carbohydrate restriction due to worsening lower limb pain. The diet is well tolerated with some reported clinical improvement. Conclusion: A simplified diet to induce ketosis, commenced at home, may be less of a burden in PDHCD. Ketogenic Diet (KD) is an effective treatment for children with intractable epilepsy. Despite energy and protein prescription fulfilling the Recommended Dietary Intake for ideal body weight and normal growth, some patients fail to grow while on the diet. We hypothesised that growth failure in patients on a KD is due to an inadequate Protein:Energy (P:E) ratio. Retrospective dietary details (protein and energy intake; P:E ratio), growth parameters and biochemical markers were collected on all patients who had been on KD for >6 m since October 2002, excluding those with a metabolic disorder (n=39; male:female: 21:18; age range 10 m-16.5 yrs. Information was incomplete for 2 patients. Twenty-four children failed to grow: 10 had a P:E intake <1.3gm/100 kcal (n=5; age1-3y and>10y) or <1.5gm/100 kcal (n=5; age3-10y). Eight had selenium deficiency (or negligible intake). Appropriate selenium intake/ blood level was confirmed in all 10 patients with low P:E ratio. Two had severe iron deficiency. Four had low energy and protein intake. Two did not grow for unknown reasons. Surprisingly, three of those who grew well (age3-8 years) had <1.3 g protein/100 kcal, were not selenium deficient and had adequate selenium intake. P:E ratio and selenium deficiency are pivotal in the growth of children on a KD. Introduction: Accurate and safe feed production is challenging for caregivers of children with IMD requiring specialist feeds with multiple ingredients. Aim: To examine the accuracy of modular feed preparation. Methods/subjects: 52 subjects (38 mothers, 13 fathers, 1 patient; 67% Asian, 29% Caucasian; 4% Afro-Caribbean) with IMD children requiring specialist feeds were studied. Two feeds, with the same nutrient composition, were made with either 2 or 6 ingredients. Following a demonstration, caregivers of children with IMD prepared both feeds under controlled conditions. Ingredients were measured by digital scales, syringe and measuring jugs. Prepared feeds were analysed for nutrient content to determine preparation accuracy. Results: The nutrient composition of both feeds was inaccurate. Nutrients within 20% of the calculated amount for the 6 ingredient feed were: carbohydrate 92%; fat 2%; sodium 33%; potassium 79%; and zinc 23%. For the 2 ingredient feed: carbohydrate was 83%; fat 65%; sodium 4%; potassium 25% and zinc 76%. Fat was calculated as a % of expected minimum value. 6 ingredients feeds were more likely to be under concentrated and 2 ingredients feeds over concentrated. Conclusion: Preparation of specialist feeds is inaccurate and there is a need to simplify feed production for caregivers of IMD children. Conflict of Interest declared. In the UK, in young children >6 months of age with PKU, the most common way of administering phenylalanine-free protein substitute (PS) is in the form of a gel/paste given from a spoon pre-meals. It is prepared by adding water to powder. Disadvantages are associated with preparation inconvenience and changeable consistency, which are prevented with a ready-to-use (RTF) preparation. Aim: To study the efficacy, acceptability and tolerance of a RTF PS gel (PKU Squeezy; Vitaflo International) in young children with PKU. Methods/subjects: In a 7 day, observational trial, 10 subjects (9 PKU; 1 DHPR deficiency; 8 boys), median age 3y (1-10y), took the RTF, nutritionally fortified, PS gel at least once daily. Caregivers completed a daily diary examining tolerance, acceptability and ease of administration. Results: Appearance and tolerance were very similar between usual PS and RTF gel. However, caregivers rated the RTF as easy to use/prepare (100% vs. 50% usual PS); easy to administer outside the home (75% vs. 40% usual PS); and easy for others to prepare and administer (100% vs. 50% usual PS). Blood phenylalanine control remained excellent. Conclusions: This RTF PS gel developed for younger PKU children was successfully adopted by patients and more convenient for caregivers. Conflict of Interest declared. Background: Previous studies have suggested vitamin D insufficiency is associated with increased obesity and metabolic risk factors. However data on the relation between vitamin D status, adiponectin, and insulin sensitivity among obese children and adolescents are lacking. The aim of this study is to investigate the relation between serum 25(OH)D, adiponectin, and insulin sensitivity in obese and non-obese children and adolescents. Patients and Methods: Data from 40 obese and 40 non-obese children and adolescents were obtained. In every participants, anthropometric variables were recorded, fasting blood was assayed for 25(OH)D, glucose, adiponectin, insulin levels and insulin resistance was estimated by homeostasis model assessment (HOMA index) Results: The mean (±SD) age of participants was 13.2±3,6. Insulin resistance was obtained in 15 of obese patients (37.5%). In the overall population 25(OH)D was significantly inversely correlated with body mass index (BMI), insulin levels and HOMA index (p<0.05), and positively correlated with adiponectin (p<0.05). Adiponectin levels were negatively correlated with HOMA index in obese group (p<0.05). Adiponectin levels were lower in obese group (p<0.05). Conclusions: We observed realtionships between adiponectin, vitamin D, and insulin sensitivity in obese children and adolescents. Dietary therapy is the major treatment of urea cycle disorders. The aim is to describe the practical aspects of dietary management of a toddler with citrullinemia where education and compliance with dietary therapy has been challenging due to language and parental education level. A variety of repeated educational approaches have been used to manage this child including: visual resources, quizzes, supermarket tours, and inpatient bedside signs to prevent feeding of inappropriate foods. Dietary analysis of protein and nutritional adequacy is limited by the parent's inability to recall food intake and count protein. All modifications to the diet must be made in person. There have been four admissions in 20 months with hyperammonemia, necessitating formal education to nursing staff. Total dietetic time spent directly with this family has been 62 hours, plus preparation time for the resources above. Inborn errors of metabolism present a challenging case for dietitians: to translate their dietary therapy into food-based therapy for families. This case demonstrates dietary education can be a lengthy, time consuming, and ongoing process due to the barriers created by language and parental education. Despite the time and resources invested, understanding of the disorder by the family is still very limited. Renal hypouricemia is a heterogeneous inherited disorder characterized by impaired tubular uric acid transport, reabsorption insufficiency and/or acceleration of secretion with severe complications, such as acute kidney injury, renal failure and nephrolithiasis. Diagnosis is based on biochemical markers: hypouricemia and increased fractional excretion of uric acid. Therapy is not available, however avoiding dehydration, vigorous exercise and alkalization of urine will minimise renal impairment. More than one hundred cases with a loss-of-function mutation in the SLC22A12 gene have been found, most of the described patients are Japanese (OMIM #220150, type 1). Four patients with renal hypouricemia caused by defects in the SLC2A9 gene have been described (OMIM #612076, type 2). We describe the findings of 12 and 14 year old nonconsanguinous boys with acute kidney injury from UK; the concentrations of serum uric acid were 0.03 and 0.04 mmol/l and expressed as an increase in the fractional excretion of uric acid (46 and 93%). A diagnosis of renal hypouricemia type 2 was made on the bases of finding two novel missence transitions resulting in amino acid substitutions p. G216R Familial juvenile hyperuricemic nephropathy (FJHN, OMIM #162000) is an autosomal dominant inherited disorder characterized by hyperuricemia with decreased renal excretion of uric acid, gout and progressive renal failure. FJHN is caused by mutation in the UMOD gene (16p12.3) coding uromodulin. In the family examined by us, the father of the patient was treated with gout, he died of chronic renal failure. The patient has been monitored since her 27 of age with hyperuricemia; gradually she developed a chronic renal insufficiency in the course of 20 years. Hyperuricemia and borderline creatinine values were also observed with the patient´s son also at the age of 27. The FJHN was diagnosed on the basis of the family medical history, examination of creatinine in serum, uric acid in serum and in urine, determination of the value of extraction fraction of uric acid and uromodulin in urine. Results of biochemical examinations were subsequently confirmed by molecular genetic analysis of UMOD gene (c.334 T>C, p.C112R) with the two abovementioned family members. Allopurinol treatment leads to normalization of serum levels of uric acid and prevents gout attacks. Regular monitoring of renal functions is necessary, in case of renal failure hemodialysis or peritoneal dialysis is recommended, and kidney transplantation. Background: Hypoxanthine phosphoribosyltranferase (HPRT) deficiency is an X-linked disorder of purine salvage. Clinical manifestations range from uric acid over production with hyperuricaemia and gout to severe neurological impairment, self-mutilation and dystonia in Lesch-Nyhan Syndrome. Molecular testing is necessary to identify female carriers within families as a prelude to prenatal diagnosis. During the period 1999-2010 the Purine Research Laboratory studied 106 patients from 68 different families. We report the spectrum of mutations identified to date. Methods: Sequencing of genomic DNA or cDNA was used to define mutations in exons and flanking intronic regions. Results: Genomic sequencing revealed mutations in 60/68 families (88%). Overall, 24 of these mutations have not been previously reported. In 8 patients, exon sequencing was not informative. Copy-DNA analysis in one patient revealed an insertion derived from a deep intronic sequence with a genomic mutation flanking this region created a false exon. Carrier testing was performed in 21 mothers of affected patients, of these 81% (17) were found to be carriers of the disease associated mutation. Conclusions: Our results confirm the extraordinary variety and complexity of mutations in HPRT deficiency. A combination of genomic and cDNA sequencing may be necessary to define mutations. Background: Purine nucleoside phosphorylase (PNP) deficiency is an autosomal recessive disorder affecting purine degradation and salvage pathways. Clinically, patients typically present with severe immunodeficiency, neurological dysfunction and autoimmunity. Biochemically, PNP deficiency may be suspected in the presence of hypouricaemia. We present clinical, biochemical and genetic data on 8 patients from 7 families identified as PNP deficient. Methods: Urine metabolites were separated and quantified on a Waters UPLC. PNP activity was measured in erythrocyte lysates. Identification of the underlying mutations was determined by DNA sequencing. Results: In seven of eight patients purine nucleoside excretion was massively elevated in urine. However, in one patient multiple blood transfusions resulted in normal PNP activity and barely detectable urine metabolites. Seven different mutations were characterised of which two were novel, c.257A>G (p.H86R) and c.770A>G (p.H257R). Interestingly, four out of eight patients diagnosed with PNP deficiency had normal serum levels of uric acid. Conclusions: To date 66 patients with PNP deficiency have been reported and 24 disease causing mutations identified. PNP deficiency should not be ruled out due to the presence of normal serum uric acid. Background: Human saliva has been extensively described for its composition of major proteins, electrolytes, cortisol, melatonin and some metabolites such as amino acids. Little is known, however, about nucleotide precursors in human saliva. Nucleotides are essential for synthesis of DNA/RNA, supplying energy, regulating G-protein signalling, and biosynthesis. Methods: Saliva samples were collected from full-term neonates, aged 1-3 days, using cotton swabs. Unstimulated fasting (morning) saliva samples were collected directly from adults. The samples were extracted and ultrafiltered, then nucleotide precursors were analysed by reversed-phase HPLC with UV-detection and mass spectrometry (with stable-isotope internal standards Discussion: Salivary concentrations of purine nucleotide precursors such as hypoxanthine, xanthine, adenosine, inosine and guanosine are surprisingly high in neonates and much higher than in plasma. Transition to lower adult levels appears to occur during the first year. These precursors in saliva may be useful biomarkers for diagnosis of inborn errors of nucleotide metabolism and the investigation of some pharmacogenetic disorders. Purine and pyrimidine disorders (PPD) represent a heterogeneous group with variable clinical signs and symptoms. Testing for PPD should ideally be done in all urine specimens investigated for inborn errors of metabolism (IEM), but this is seldom done due to the low prevalence. Thus, metabolic laboratories face the challenge of selecting the samples for determination of purines and pyrimidines (PP). In our laboratory, which is responsible for selective screening for IEM in Denmark, urine samples are analysed for PP in case of 1) increased/ decreased uric acid excretion or 2) if the patient has symptoms of an immunological disease, intractable seizures, self-mutilation, hypertonicity, autism or any symptoms that may be related to kidney stone formation or nephrolitiasis.