Muscle and Bone Health in Young Chilean Adults with Phenylketonuria and Different Degrees of Compliance with the Phenylalanine Restricted Diet.

There are concerns about muscle and bone health in patients with Phenylketonuria (PKU). Our aim was to compare muscle mass, function, and bone health among young adults with PKU who maintained or suspended dietary treatment. METHODS: Three groups were considered-PKU-1: 10 patients who used a protein substitute (PS) without phenylalanine (Phe); PKU-2: 14 patients who used the PS without Phe until eighteen years old and then practiced mostly a vegan diet; and 24 matched healthy controls. A 24 h recall survey, blood parameters, body composition and bone mineral density through DEXA, rectus femoris thickness by ultrasound, hand grip strength, submaximal exercise test, and walking speed were assessed. RESULTS: PKU-1 patients had lower hand grip strength than their matched controls, but no other differences. Compared to controls, the PKU-2 group had lower fat-free mass (p = 0.01), less spine and femoral bone mineral density (p = 0.04 and p < 0.01, respectively), and peak workload on the incremental test (p = 0.03). When comparing PKU groups, blood Phe levels were significantly lower in the PKU-1 group (p = 0.02). CONCLUSIONS: Among PKU patients, abandoning the dietary treatment and maintaining high blood Phe concentrations could be deleterious for muscles and bones. However, we cannot discard other causes of bone and muscle damage in these patients.

[Hepatic glycogen storage diseases: Symptoms, management and associated mutations]. / Enfermedades por depósito de glucógeno hepático: Clínica, manejo y mutaciones asociadas.

Glycogen storage diseases (GSD) are rare diseases derived from altered glycogen metabolism. This leads to glycogen storage in different organs such as muscle, kidney, and liver, resulting in a variety of clinical manifestations. GSD with liver involvement are classified into types I, III, IV, VI, and IX, depending on the enzymes affected. They are clinically characterized by hypoglycemia and hepato megaly as cardinal signs. Their diagnosis is initially based on clinical manifestations and laboratory test results. Nevertheless, diagnostic certainty requires a genetic study that identifies the specific mutation. Multiple mutations have been associated with each GSD. In Chile, since patients often lack the genetic study, the GSD genetic local characteristics are unknown. The treatment is based on dietary restrictions modulated according to the identified mutation. Today, the international consen sus indicates that early diagnosis allows better metabolic control and improves the patient's quality of life and prognosis. In this review, the information on GSD with liver involvement is updated to optimize the diagnosis, treatment, and follow-up of these patients, emphasizing specific nutritional and gastroenterological management.

Maple syrup urine disease: Characteristics of diagnosis and treatment in 45 patients in Chile.

Maple urine syrup disease (MSUD) is an autosomal recessive disorder characterized by deficient activity of the branched-chain alpha ketoacid dehydrogenase (BCKAD) enzymatic complex due to biallelic variants in the alpha (BCKDHA) or beta (BCKDHB) subunits or the acyltransferase component (DBT). Treatment consists in leucine (LEU), isoleucine (ILE), and valine (VAL) (branched-chain amino acids) dietary restriction and strict metabolic control. to determine the characteristics of the Chilean cohort with MSUD currently in follow-up at Instituto de Nutrición y Tecnología de los Alimentos, during the 1990-2017 period Retrospective analytical study in 45 MSUD cases. Measured: biochemical parameters (LEU, ILE, and VAL), anthropometric evaluation, and neurocognitive development. In 18 cases undergoing genetic study were analyzed according to the gene and protein location, number of affected alleles, and type of posttranslational modification affected. Then, 45 patients with MSUD diagnosis were identified during the period: 37 were alive at the time of the study. Average diagnosis age was 71 ± 231 days. Average serum diagnosis LEU concentrations: 1.463 ± 854.1 µmol/L, VAL 550 ± 598 µmol/L and ILE 454 ± 458 µmol/L. BCKDHB variants explain 89% cases, while BCKDHA and DBT variants explain 5.5% of cases each. Variants p.Thr338Ile in BCKDHA, p.Pro240Thr and p.Ser342Asn in BCKDHB have not been previously reported in literature. Average serum follow-up LEU concentrations were 252.7 ± 16.9 µmol/L in the <5 years group and 299 ± 123.2 µmol/L in ≥5 years. Most cases presented some degree of developmental delay. Early diagnosis and treatment is essential to improve the long-term prognosis. Frequent blood LEU measurements are required to optimize metabolic control and to establish relationships between different aspects analyzed.

Clinical and Nutritional Evolution of 24 Patients with Glutaric Aciduria Type 1 in Follow-up at a Center Specialized in Inborn Errors of Metabolism in Chile

Abstract Introduction: Glutaric Aciduria Type 1 (GA-1) is produced by the enzymatic deficiency of glutaryl-CoA-dehydrogenase (GCDH), leading to the accumulation of glutaric acid (GA). 90% of patients without early treatment present acute encephalopathic crisis (AEC), followed by disabling neurological symptoms. The treatment consists of a low lysine (Lys) diet, protein substitute lys-free, tryptophan-reduced (PS) and L-carnitine. Objectives: Describe the clinical and nutritional evolution of a cohort of GA-1 patients at a national referral center in Chile. Methodology: Retrospective study of 24 patients diagnosed with GA-1 between 1998-2020 and referred to the Institute of Nutrition and Food Technology (INTA) of University of Chile. Results: Age at diagnosis was 19±27 months; 10/24 presented AEC and neurological sequelae. The cases without AEC (14/24) 8 presented neurological compromise: psychomotor development delay, abnormal movements and pyramidal syndrome. Nutritional evaluation: 12/24 were malnourished by deficiency, <6 years old group (12/24): 11 cases were found to have Lys and PS, ≥6 years old (12/24): 9/12 did not receive PS. All had normal free carnitine levels. Conclusion: GA-1 has variable symptoms with neurological involvement AEC or insidious start. Is essential to maintain a long-term follow-up and consider its inclusion in neonatal screening programs.

First-year metabolic control guidelines and their impact on future metabolic control and neurocognitive functioning in children with PKU.

There is a consensus on the importance of early and life-long treatment for PKU patients. Still, differences exist on target blood phenylalanine (Phe) concentrations for children with PKU in different countries and treatment centers. For the first time, long-term metabolic control and child development and cognitive functioning is compared between children with mean phenylalanine concentrations under 240 µmol/L (group A), between 240 and 360 µmol/L (group B) or over 360 µmol/L (group C) during their first year of life. METHODS: 70 patients diagnosed with PKU through neonatal screening with Phe > 900 µmol/L, were divided into 3 groups: A, B and C, according to mean Phe concentrations and standard deviation (SD). Metabolic control during childhood, psychomotor development and IQ were compared. RESULTS: In group A, Phe was maintained within the recommended range until 6 years of age, in Group B, until 3 years of age, and in group C, Phe was always over the recommended range. No significant differences were found between the three groups in mental development index (MDI) and motor development index (PDI) scores at 12, 24, and 30 months of age, but group C had the lowest scores on MDI at all age periods. At preschool and school age, IQ was higher in group A compared to group C. CONCLUSION: Results show that mean blood Phe concentrations between 120 and 240 µmol/L during first year of life have a positive impact in metabolic control and cognitive functioning during childhood.

Long-term cognitive functioning in individuals with tyrosinemia type 1 treated with nitisinone and protein-restricted diet.

INTRODUCTION: Tyrosinemia Type 1 (HT1) is an autosomal recessive disorder caused by a defect in the enzyme fumarylacetoacetate hydroxylase in the tyrosine pathway. Implementation of nitisinone (NTBC) treatment has dramatically improved survival rate of individuals with HT1, yet recent reports on cognitive impairment in treated patients exist. AIMS: Describe long-term neurocognitive outcome individuals with HT1 treated with nitisinone and protein restricted diet. METHODOLOGY: Twelve individuals with HT1 were analyzed with respect to psychomotor development and cognitive functioning using standardized psychometric tests. Plasma tyrosine and phenylalanine concentrations were also collected and analyzed, as part of the regular HT1 follow up program in our clinic. RESULTS: Delayed performance in Bayley scale mental developmental index (MDI) was identified in 29% to 38% of the patients assessed at different ages. At preschool age, mean full scale IQ (FSIQ) was 88 ± 16; six out of nine assessed children preformed within normal range, and one child presented with intellectual disability. At school age mean FSIQ was 79 ± 18, three out of nine children preformed within normal range and two showed intellectual disability. Repeated measures showed IQ decline over time in four out of eight patients, all of whom presented with symptoms in their first months of life. Patients that showed no progressive IQ decline were 8 months or older at diagnosis, with a mean age of 17 months. Significant correlation between Phe/Tyr ratio and FSIQ at school age was identified (r = - 0.689; p < 0.044). CONCLUSION: Some patients with HT1 treated with nitisinone and protein restricted diet are at risk of presenting developmental delay and impaired cognitive functioning. Patients with early onset of symptoms could be at risk for progressive cognitive functioning decline over time.

Energy Expenditure in Chilean Children with Maple Syrup Urine Disease (MSUD).

INTRODUCTION: Maple syrup urine disease (MSUD) is an autosomal recessive disorder caused by a blockage of branched-chain keto acid of BCAA (branched-chain keto acid dehydrogenase, BCKDH) leading to neurological damage induced by accumulation of leucine and metabolites. MSUD expenditure and energy requirement information is limited. OBJECTIVE: To determine if basal/total energy expenditure (BEE/TEE) is comparable between different determination methods and if values agree with recommendations of energy in MSUD children, and whether they relate to nutritional status. METHODS: Case-control study between MSUD (n = 16) and healthy children (n = 11) aged 6-18 years. Current nutritional status, physical activity level, body composition by DEXA and BEE/TEE by indirect calorimetry (BEEr) and predictive equations (FAO/WHO/ONU - WHO - and Schofield) were assessed; STATA 2013 (p < 0.05). RESULTS: When comparing the energy expenditure variables, there was no significant difference between groups. Moreover, compared to BEEr, equations underestimate according to BEE WHO and Schofield, respectively (P = 0.00; 0.02). The WHO equation had lower average calorie difference, greater concordance correlation and association with indirect calorimetry compared to the Schofield equation for both groups, being the best predictor of the BEE for MSUD group. CONCLUSION: Energy recommendations for MSUD children are according to energy expenditure; thus the use of WHO equation is a clinically and statistically feasible tool for its determination.

[What should the paediatrician know about hyperphenylalaninaemia?]. / ¿Qué debe saber el pediatra de las hiperfenilalaninemias?

Hyperphenylalaninaemias are defined by a blood phenylalanine over 2mg/dl. The main cause is due to a mutation in the gene that codes the phenylalanine hydroxylase that catalyses the reaction that converts phenylalanine into tyrosine. The hyperphenylalaninaemias are classified into benign or mild hyperphenylalaninaemias, or mild, moderate or classic phenylketonurias. Due to its delayed detection outside the neonatal period it causes severe mental retardation. Its detection along with congenital hypothyroidism has been part of the National Neonatal Screening Program since 1992 in Chile. This article aims to answer the most common questions asked by the paediatrician when faced with a patient with hyperphenylalaninaemias.

¿Qué debe saber el pediatra de las hiperfenilalaninemias? / What should the paediatrician know about hyperphenylalaninaemia?

Las hiperfenilalaninemias se definen por un nivel sanguíneo de fenilalanina sobre 2 mg/dl. La principal causa es una mutación en el gen que codifica la fenilalanina hidroxilasa que cataliza la reacción que transforma la fenilalanina en tirosina. Las hiperfenilalaninemias se clasifican en benignas o leves, y las fenilcetonurias en leves, moderadas y clásicas. Debido a que su detección más allá del periodo neonatal causa retardo mental severo, desde 1992 en Chile su detección, junto con la del hipotirodismo congénito, es parte del Programa Nacional de Pesquisa Neonatal. Este artículo pretende responder las preguntas más comunes que se puede hacer el pediatra cuando enfrenta a un paciente con hiperfenilalaninemias.

Hyperphenylalaninaemias are defined by a blood phenylalanine over 2 mg/dl. The main cause is due to a mutation in the gene that codes the phenylalanine hydroxylase that catalyses the reaction that converts phenylalanine into tyrosine. The hyperphenylalaninaemias are classified into benign or mild hyperphenylalaninaemias, or mild, moderate or classic phenylketonurias. Due to its delayed detection outside the neonatal period it causes severe mental retardation. Its detection along with congenital hypothyroidism has been part of the National Neonatal Screening Program since 1992 in Chile. This article aims to answer the most common questions asked by the paediatrician when faced with a patient with hyperphenylalaninaemias.

Guidelines for diagnosis and treatment of Hunter Syndrome for clinicians in Latin America.

This review aims to provide clinicians in Latin America with the most current information on the clinical aspects, diagnosis, and management of Hunter syndrome, a serious and progressive disease for which specific treatment is available. Hunter syndrome is a genetic disorder where iduronate-2-sulfatase (I2S), an enzyme that degrades glycosaminoglycans, is absent or deficient. Clinical manifestations vary widely in severity and involve multiple organs and tissues. An attenuated and a severe phenotype are recognized depending on the degree of cognitive impairment. Early diagnosis is vital for disease management. Clinical signs common to children with Hunter syndrome include inguinal hernia, frequent ear and respiratory infections, facial dysmorphisms, macrocephaly, bone dysplasia, short stature, sleep apnea, and behavior problems. Diagnosis is based on screening urinary glycosaminoglycans and confirmation by measuring I2S activity and analyzing I2S gene mutations. Idursulfase (recombinant I2S) (Elaprase(®), Shire) enzyme replacement therapy (ERT), designed to address the underlying enzyme deficiency, is approved treatment and improves walking capacity and respiratory function, and reduces spleen and liver size and urinary glycosaminoglycan levels. Additional measures, responding to the multi-organ manifestations, such as abdominal/inguinal hernia repair, carpal tunnel surgery, and cardiac valve replacement, should also be considered. Investigational treatment options such as intrathecal ERT are active areas of research, and bone marrow transplantation is in clinical practice. Communication among care providers, social workers, patients and families is essential to inform and guide their decisions, establish realistic expectations, and assess patients' responses.

Propionic acidemia and optic neuropathy: a report of two cases.

INTRODUCTION: Propionic acidemia is a metabolic disease produced by a deficiency of the enzyme propionyl-CoA carboxylase. It can lead to coma, with severe neurologic encephalopathy or present later in life with vomiting, hypotonia, and seizures. An early diagnosis with adequate treatment helps to prevent the sequelae. Among the described complications is optic neuropathy, although not commonly reported, it is very disabling. OBJECTIVES: To describe two patients with propionic acidemia and optic neuropathy. PATIENTS AND METHODS: Patient 1: 16 years old, male, parents without consanguinity. He was diagnosed at 5 months of age because of hypotonia and seizures. Until the age of 9 years, he evolved satisfactorily; therefore, he stopped treatment. At 13 years, he presented bilateral optic neuropathy. Patient 2: 20 years, female, parents without consanguinity. She was diagnosed with PA at 11 months of age because of hypotonia and seizures. She evolved satisfactorily until the age of 9 years when she presented a metabolic decompensation followed by a bad metabolic control. At 18 years, she presented bilateral progressive optic neuropathy. RESULTS: Both patients have psychometric scores with borderline IQ 84-75 (WISC-R) beside optic neuropathy. They were evaluated by an ophthalmologist and also by neuroimaging (MRI of optic pathway). CONCLUSIONS: Pathophysiology of optic neuropathy is not completely understood. There is evidence that the damage is due to an accumulation of neurotoxic compounds secondary to the metabolic block increasing the oxidative stress. We suggest an annual ophthalmologic evaluation in the long-term follow-up of organic acidurias with visual loss, in order to detect this disabling sequela at an earlier stage.

[Gaucher disease in Latin America. A report from the Gaucher Disease International Registry and the Latin American Group for Gaucher Disease]. / Enfermedad de Gaucher en Latinoamérica. Un informe del Registro Internacional y del Grupo Latinoamericano para la enfermedad de Gaucher.

Gaucher disease -due to its low frequency- is considered an orphan disease. In 1991 the International Gaucher Registry was created and in 1992 the first patients from Latin America were enrolled. In 2008 the Latin American Group for Gaucher Disease was initiated. Its main objectives are to promote regional consensus, to stimulate the enrollment of patients into the International Gaucher Registry and the enhancement of knowledge on this disease, and to achieve better care and quality of life of patients in our Region. Until April 2010, 5828 patients have been enrolled all around the world, 911 (15.6%) from Latin America. This is the first comprehensive report of the disease in the Region. In our population there is a predominance of females, the most common clinical form is the type I (95%) and the age at diagnosis is before 20 years in 68% of patients. The most frequent clinical manifestations at diagnosis are splenomegaly (96%) and anemia (49%). Eighty percent of patients had radiographic findings of bone involvement. In our Region, the vast majority of patients (89%) had received enzyme replacement therapy with imiglucerase; with a long follow-up (up to 10 years) they have achieved the therapeutic goals, showing the great effectiveness of therapy. While the percentage of patients with therapy is high, discontinuations are common. The main deficiencies in our Region are: the lack of visceral volumetric evaluations and densitometries as well as molecular analysis for some patients. The main problem is the under-diagnosis of patients.

Enfermedad de Gaucher en Latinoamérica: Un informe del Registro Internacional y del Grupo Latinoamericano para la Enfermedad de Gaucher / Gaucher disease in Latin America: A report from the Gaucher Disease International Registry and the Latin Americam Group for Gaucher Disease

La enfermedad de Gaucher, por su escasa frecuencia, está incluida dentro de las llamadas enfermedades huérfanas. En 1991 se creó el Registro Internacional de Gaucher y en 1992 se incorporaron los primeros pacientes de Latinoamérica. En el año 2008 se creó el Grupo Latinoamericano para la Enfermedad de Gaucher (GLAEG) cuyos principales objetivos son fomentar la realización de consensos regionales, difundir el ingreso de pacientes al registro internacional y aumentar el conocimiento sobre la enfermedad para lograr mejorar la atención y la calidad de vida de los pacientes. Hasta abril del 2010 ingresaron 5828 pacientes de todo el mundo, 911 (15.6%) son de Latinoamérica. Este es el primer informe global de la enfermedad en la Región: hay un predominio del sexo femenino, la forma clínica más frecuente es el tipo I (95%); al diagnóstico la mayoría son <20 años (68%). Las manifestaciones clínicas más frecuentes al diagnóstico son esplenomegalia (96%) y anemia (49%), el 80% presentó hallazgos radiológicos de compromiso óseo. En nuestra Región, la gran mayoría de los pacientes (89%) ha recibido alguna vez terapia de reemplazo enzimática con imiglucerasa logrando, con un seguimiento prolongado (hasta10 años), las metas terapéuticas que muestran la gran eficacia de la terapia. Si bien el porcentaje de pacientes con terapia es alto, las suspensiones de tratamiento son frecuentes. Las principales deficiencias en nuestra Región son: la carencia de evaluaciones viscerales volumétricas, de densitometría y de estudios moleculares en algunos pacientes. El principal problema es el subdiagnóstico.

Gaucher disease -due to its low frequency- is considered an orphan disease. In 1991 the International Gaucher Registry was created and in 1992 the first patients from Latin America were enrolled. In 2008 the Latin American Group for Gaucher Disease was initiated. Its main objectives are to promote regional consensus, to stimulate the enrolment of patients into the International Gaucher Registry and the enhancement of knowledge on this disease, and to achieve better care and quality of life of patients in our Region. Until April 2010, 5828 patients have been enrolled all around the world, 911 (15.6%) from Latin America. This is the first comprehensive report of the disease in the Region. In our population there is a predominance of females, the most common clinical form is the type I (95%) and the age at diagnosis is before 20 years in 68% of patients. The most frequent clinical manifestations at diagnosis are splenomegaly (96%) and anemia (49%). Eighty percent of patients had radiographic findings of bone involvement. In our Region, the vast majority of patients (89%) had received enzyme replacement therapy with imiglucerase; with a long follow-up (up to 10 years) they have achieved the therapeutic goals, showing the great effectiveness of therapy. While the percentage of patients with therapy is high, discontinuations are common. The main deficiencies in our Region are: the lack of visceral volumetric evaluations and densitometries as well as molecular analysis for some patients. The main problem is the under-diagnosis of patients.

Efectos de la prematurez sobre el desarrollo cognitivo y la atención en etapa escolar / Effects of prematurity on cognitive development and attention at school age

Gracias a los avances tecnológicos, los niños prematuros con discapacidades físicas mayores han disminuido su prevalencia; actualmente, los defectos cognitivos son la secuela predominante. Se investigó el desarrollo cognitivo y la atención en escolares con antecedentes de haber sido recién nacidos prematuros, a través de un estudio descriptivo, de corte transversal, en que se realizaron evaluaciones neuropsicológicas mediante WISC-R y test de Gordon a niños escolares con antecedentes de prematurez (EG<33s y/o PN<1500g) y niños controles con antecedentes de ser recién nacidos de término. Se evaluó a 77 pacientes: 40 niños prematuros (EG: 30,5 s) y 37 de término, entre 6-7 años. Aunque ambos grupos obtuvieron un CIT dentro del rango normal, se observó diferencias significativas (p<0,03) en desmedro del grupo prematuro en comparación con controles. Las habilidades atencionales también fueron significativamente menores para los prematuros (p< 0,01). Los niños prematuros se encuentran en riesgo de presentar problemas cognitivos y/o de atención en la etapa escolar. Se sugiere incorporar instrumentos de pesquisa de estas dificultades durante el seguimiento, que permitan un reconocimiento precoz e intervención oportuna.

The prevalence of premature children with major physical disabilities has diminished over time mainly due to advances in technology. Cognitive disorders are currently the main sequels. In order to study cognitive and attentional functioning of extremely premature infants at school age, a cross sectional study was designed. Neuropsychological assessments were performed by WISC-R and Gordon test, in prematures and controls at school age. Seventy seven children, 40 preterm (GA: 30.5 w) and 37 term at birth, aged 6-7 years-old were assessed. Although both groups obtained an overall IQ within the normal range, prematures showed significantly lower scores than the control group (p< 0.03). Attentional skills were also significantly lower (p <0.01) in the premature children. Children with a history of extreme prematurity are at risk for cognitive and attention impairment at school age. We suggest to introduce screening tools during follow-up which allow early recognition and appropriate intervention.

Enfermedad de Gaucher en Latinoamérica: Un informe del Registro Internacional y del Grupo Latinoamericano para la Enfermedad de Gaucher / Gaucher disease in Latin America: A report from the Gaucher Disease International Registry and the Latin Americam Group for Gaucher Disease

La enfermedad de Gaucher, por su escasa frecuencia, está incluida dentro de las llamadas enfermedades huérfanas. En 1991 se creó el Registro Internacional de Gaucher y en 1992 se incorporaron los primeros pacientes de Latinoamérica. En el año 2008 se creó el Grupo Latinoamericano para la Enfermedad de Gaucher (GLAEG) cuyos principales objetivos son fomentar la realización de consensos regionales, difundir el ingreso de pacientes al registro internacional y aumentar el conocimiento sobre la enfermedad para lograr mejorar la atención y la calidad de vida de los pacientes. Hasta abril del 2010 ingresaron 5828 pacientes de todo el mundo, 911 (15.6%) son de Latinoamérica. Este es el primer informe global de la enfermedad en la Región: hay un predominio del sexo femenino, la forma clínica más frecuente es el tipo I (95%); al diagnóstico la mayoría son <20 años (68%). Las manifestaciones clínicas más frecuentes al diagnóstico son esplenomegalia (96%) y anemia (49%), el 80% presentó hallazgos radiológicos de compromiso óseo. En nuestra Región, la gran mayoría de los pacientes (89%) ha recibido alguna vez terapia de reemplazo enzimática con imiglucerasa logrando, con un seguimiento prolongado (hasta10 años), las metas terapéuticas que muestran la gran eficacia de la terapia. Si bien el porcentaje de pacientes con terapia es alto, las suspensiones de tratamiento son frecuentes. Las principales deficiencias en nuestra Región son: la carencia de evaluaciones viscerales volumétricas, de densitometría y de estudios moleculares en algunos pacientes. El principal problema es el subdiagnóstico.(AU)

Gaucher disease -due to its low frequency- is considered an orphan disease. In 1991 the International Gaucher Registry was created and in 1992 the first patients from Latin America were enrolled. In 2008 the Latin American Group for Gaucher Disease was initiated. Its main objectives are to promote regional consensus, to stimulate the enrolment of patients into the International Gaucher Registry and the enhancement of knowledge on this disease, and to achieve better care and quality of life of patients in our Region. Until April 2010, 5828 patients have been enrolled all around the world, 911 (15.6%) from Latin America. This is the first comprehensive report of the disease in the Region. In our population there is a predominance of females, the most common clinical form is the type I (95%) and the age at diagnosis is before 20 years in 68% of patients. The most frequent clinical manifestations at diagnosis are splenomegaly (96%) and anemia (49%). Eighty percent of patients had radiographic findings of bone involvement. In our Region, the vast majority of patients (89%) had received enzyme replacement therapy with imiglucerase; with a long follow-up (up to 10 years) they have achieved the therapeutic goals, showing the great effectiveness of therapy. While the percentage of patients with therapy is high, discontinuations are common. The main deficiencies in our Region are: the lack of visceral volumetric evaluations and densitometries as well as molecular analysis for some patients. The main problem is the under-diagnosis of patients.(AU)

[Clinical follow up of Chilean patients with tyrosinemia type 1 treated with 2-(2-nitro-4-trifluoromethylbenzoyl)-1,3-ciclohexanedione (NTBC)]. / Evolución clínica de pacientes chilenos con tirosinemia tipo I tratados con 2-(2-nitro-4-trifluorometilbenzoil)-1,3-ciclohexanediona (NTBC).

BACKGROUND: Tyrosinemia type I is an inborn error of metabolism due to deficiency of fumarilacetoacetase. Acute presentation is with liver failure, hypophosphatemic rickets and peripheral neuropathy. Chronic presentation is with visceromegaly and subclinical rickets. The most severe complications are hepatic cancer and acute neurological crises. Without treatment, tyrosinemia type 1 is fatal. In 1992 treatment for tyrosinemia type 1 with 2-(2-nitro-4-trifluoromethybenzoyl)-1,3-ciclohexanedione (NTBC) was proposed. A clinical response was reported in 90% of patients. In cases that did not respond, a successful liver transplantation was performed, reducing mortality to 5%. AIM: To report the follow up of 12 patients treated with NTBC. PATIENTS AND METHODS: Review of clinical records of 12 Chilean cases treated with NTBC at the Instituto de Nutrición y Tecnología de los Alimentos (INTA) from January 2004 until June 2010. RESULTS: In all patients, a rapid metabolic control was achieved. Two patients developed hepatocarcinoma. One of these patients died and one was successfully treated with liver transplantation. One patient died after receiving a liver transplantation. Nine patients have at present good liver function, but 2 had peripheral neuropathy due to late diagnosis and discontinuing NTBC treatment. CONCLUSIONS: Treatment with NTBC allows metabolic normalization in tyrosinemia type 1, prevents liver cirrhosis and hepatic cancer, improving survival rates and quality of life in the patients. Neonatal screening is essential for the early diagnosis of this treatable disease, that otherwise may be lethal.

Evolución clínica de pacientes chilenos con tirosinemia tipo I tratados con 2-(2-nitro-4-trifluorometilbenzoil)-1,3-ciclohexanediona (NTBC) / Clinical follow up of Chilean patients with tyrosinemia type 1 treated with 2-(2-nitro-4-trifluoromethylbenzoyl)-1,3-ciclohexanedione (NTBC)

Background: Tyrosinemia type I is an inborn error of metabolism due to deficiency of fumarilacetoacetase. Acute presentation is with liver failure, hypophosphatemic rickets and peripheral neuropathy. Chronic presentation is with visceromegaly and subclinical rickets. The most severe complications are hepatic cancer and acute neurological crises. Without treatment, tyrosinemia type 1 is fatal. In 1992 treatment for tyrosinemia type 1 with 2-(2-nitro-4-trifluoromethybenzoyl)-1,3-ciclohexanedione (NTBC) was proposed. A clinical response was reported in 90% of patients. In cases that did not respond, a successful liver transplantation was performed, reducing mortality to 5%. Aim: To report the follow up of 12 patients treated with NTBC. Patients and Methods: Review of clinical records of 12 Chilean cases treated with NTBC at the Instituto de Nutrición y Tecnología de los Alimentos (INTA) from January 2004 until June 2010. Results: In all patients, a rapid metabolic control was achieved. Two patients developed hepatocarcinoma. One of these patients died and one was successfully treated with liver transplantation. One patient died after receiving a liver transplantation. Nine patients have at present good liver function, but 2 had peripheral neuropathy due to late diagnosis and discontinuing NTBC treatment. Conclusions: Treatment with NTBC allows metabolic normalization in tyrosinemia type 1, prevents liver cirrhosis and hepatic cancer, improving survival rates and quality of life in the patients. Neonatal screening is essential for the early diagnosis of this treatable disease, that otherwise may be lethal.

Clinical manifestations and treatment of mucopolysaccharidosis type I patients in Latin America as compared with the rest of the world.

BACKGROUND: Mucopolysaccharidosis I (MPS I) comprises a spectrum of clinical manifestations and is divided into three phenotypes reflecting clinical severity: Hurler, Hurler-Scheie, and Scheie syndromes. There may be important variations in clinical manifestations of this genetic disease in patients residing in different regions of the world. METHODS: Using data from the MPS I Registry (as of September 2009), we evaluated patients from Latin America (n = 118) compared with patients from the rest of the world [ROW (n = 727)]. RESULTS: Phenotype distribution differed among patients in Latin America compared to ROW (Hurler 31 vs. 62%, Hurler-Scheie 36 vs. 21%, Scheie 10 vs. 11%, and unknown 22 vs. 6%). The frequency of certain symptoms, such as cardiac valve abnormalities, sleep impairment, and joint contractures, also differed between Latin America and ROW for some phenotypes. Median age at MPS I diagnosis was earlier in the ROW than Latin America for all phenotypes, and age at first treatment for Hurler and Hurler-Scheie patients was also earlier in the ROW. Hurler patients in Latin America showed a gap of 3.1 years between median ages of diagnosis and first treatment compared to only 0.5 years in the ROW. Treatment allocation in Latin America compared to ROW was as follows: enzyme replacement therapy (ERT) only, 80 vs. 45%; hematopoietic stem cell transplantation (HSCT) only, 0.9 vs. 27%; both ERT and HSCT, 0 vs. 16%; and neither treatment, 19 vs. 13%. CONCLUSION: These data highlight important differences in MPS I patients between Latin America and ROW in terms of phenotypic distribution, clinical manifestations, and treatment practices.

[Glucose transponer type 1 deficiency síndrome (GLUT-1 SD) treated with ketogenic diet. Report of one case]. / Síndrome de deficiencia del transportador de glucosa tipo 1 (SDGLUT-1) tratado con dieta cetogénica. Caso clínico.

The glucose transporter type 1 deficiency syndrome (GLUT-1 SD) (OMIM 606777) is an inborn error of metabolism of brain glucose transport. The characteristic clinical manifestations are seizures, hypotonia, developmental delay, microcephaly and hypoglycorrhachia. We report a girl with normal weight and height at birth. At 6 weeks of age she started with convulsions reaching up to 20 myoclonic seizures a day. She was treated with valproate, phenobarbital and carbamazepine without response. Blood analysis including aminoacids and acylcarnitines were all normal. The brain MRI showed frontal atrophy with an increased subarachnoidal space and Electroencephalography was abnormal. Blood glucose was 84 mg/dl and spinal fluid glucose 26 mg/dl with a ratio of 0.31 (Normal Ratio >0.65+/-00.1). These results suggested the diagnosis of GLUT-1 SD, and was confirmed with erythrocyte glucose uptake of 44% (Normal range 80-100%). A molecular study found the mutation 969del, C971T in exon 6 of the gene Glut-1. Treatment with a ketogenic diet was started immediately and after 7 days with this diet seizures ceased. Anticonvulsants were progressively suspended. At present, the patient is 6 years old, she continues on a ketogenic diet and supplements with L-carnitine, lipoic acid, vitamins and minerals. Growth and development are normal with an intelligence quotient of 103. It is concluded that it is necessary to include GLUT-1 SD in the differential diagnosis of children with early seizures that are non responsive to pharmacological treatment.

Composición lipidica de la dieta de niños fenilquetonúricos diagnosticados precozmente / Lipids composition diet in phenylketonuric children with early diagnosis

La Fenilquetonuria (PKU) se produce por un defecto total o parcial de la enzima fenilalanina hidroxilasa (FAH) acumulándose fenilalanina (FA) en sangre, lo que ocasiona retardo mental si no es diagnosticada en el período de recién nacido. El tratamiento consiste en una dieta restringida en FA. Diversos estudios han señalado que debido a la restricción de proteínas animales, la dieta es deficiente en ácidos grasos: alfalinolénico (ALL) y elevada en ácidos linoléico (AL). El objetivo de este estudio fue determinar la ingesta de lípidos en niños PKU diagnosticados precozmente, estudiándose la composición química de lípidos de la dieta de 29 niños con PKU, en dieta restringida en FA y en seguimiento en el INTA, Universidad de Chile. Fueron pareados por sexo y edad con un grupo control. Se aplicó encuesta de recordatorio de 24 horas por tres días consecutivos, calculándose la ingesta de ácidos grasos totales, saturados, monoinsaturados, poliinsaturados, AL y ALL. Los resultados muestran que la dieta de los PKU aporta el 31.8 por ciento como calorías grasas, de los cuales el 13 por ciento es AL y un 0.2 por ciento ALL, existiendo diferencias significativas con respecto al grupo control. La relación obtenida entre ácidos grasos saturados-monoinsaturados-poliinsaturados fue de 1:1.7:3.9 y la razón entre AL y ALL fue diez veces más de lo recomendado (115:1). Concluyéndose que la dieta de los niños PKU chilenos contiene mayor cantidad de AL y menor de ALL