Intravenous branched-chain amino-acid-free solution for the treatment of metabolic decompensation episodes in Spanish pediatric patients with maple syrup urine disease.

Background: Metabolic decompensation episodes (DEs) in Maple Syrup urine disease (MSUD) result in brain accumulation of toxic branched-chain amino acids (BCAAs) and their respective branched-chain α-keto acids that could induce neuroinflammation, disturb brain bioenergetics, and alter glutamate and glutamine synthesis. These episodes require immediate intervention to prevent irreversible neurological damage. Intravenous (IV) administration of BCAA-free solution could represent a powerful alternative for emergency treatment of decompensations. Methods: This pediatric series discusses the management of DEs in MSUD patients with IV BCAA-free solution, as an emergency treatment for DEs or as a prophylactic in cases requiring surgery. Clinical evolution, amino acid profile and adverse effects were evaluated. Results: We evaluated the use of BCAA-free solution in 5 DEs in 5 MSUD pediatric patients, all with significantly elevated plasma leucine levels at admission (699-3296 µmol/L) and in 1 episode of risk of DE due to surgery. Leucine normalization was achieved in all cases with resolution or improvement of clinical symptoms following IV BCAA-free solution. The duration of administration ranged from 3-20 days. Administration of IV BCAA-free solution at the beginning of a DE could reverse depletion of the amino acids that compete with BCAAs for the LAT1 transporter, and the observed depletion of alanine, despite IV alanine supplementation. No related adverse events were observed. Conclusions: Administration of standardized IV BCAA-free solution in emergency settings constitutes an important and safe alternative for the treatment of DEs in MSUD, especially in pediatric patients for whom oral or enteral treatment is not viable.

Newborn screening for homocystinurias: Recent recommendations versus current practice.

PURPOSE: To assess how the current practice of newborn screening (NBS) for homocystinurias compares with published recommendations. METHODS: Twenty-two of 32 NBS programmes from 18 countries screened for at least one form of homocystinuria. Centres provided pseudonymised NBS data from patients with cystathionine beta-synthase deficiency (CBSD, n = 19), methionine adenosyltransferase I/III deficiency (MATI/IIID, n = 28), combined remethylation disorder (cRMD, n = 56) and isolated remethylation disorder (iRMD), including methylenetetrahydrofolate reductase deficiency (MTHFRD) (n = 8). Markers and decision limits were converted to multiples of the median (MoM) to allow comparison between centres. RESULTS: NBS programmes, algorithms and decision limits varied considerably. Only nine centres used the recommended second-tier marker total homocysteine (tHcy). The median decision limits of all centres were ≥ 2.35 for high and ≤ 0.44 MoM for low methionine, ≥ 1.95 for high and ≤ 0.47 MoM for low methionine/phenylalanine, ≥ 2.54 for high propionylcarnitine and ≥ 2.78 MoM for propionylcarnitine/acetylcarnitine. These decision limits alone had a 100%, 100%, 86% and 84% sensitivity for the detection of CBSD, MATI/IIID, iRMD and cRMD, respectively, but failed to detect six individuals with cRMD. To enhance sensitivity and decrease second-tier testing costs, we further adapted these decision limits using the data of 15 000 healthy newborns. CONCLUSIONS: Due to the favorable outcome of early treated patients, NBS for homocystinurias is recommended. To improve NBS, decision limits should be revised considering the population median. Relevant markers should be combined; use of the postanalytical tools offered by the CLIR project (Collaborative Laboratory Integrated Reports, which considers, for example, birth weight and gestational age) is recommended. tHcy and methylmalonic acid should be implemented as second-tier markers.

The Role of Liver Transplantation in Propionic Acidemia.

Despite optimal medical treatment and strict low-protein diet, the prognosis of propionic acidemia (PA) patients is generally poor. We aim to report our experience with liver transplantation (LT) in the management of PA patients. Six patients with PA received a LT at a mean age of 5.2 years (1.3-7.5 years). The indications for LT were frequent metabolic decompensations in the first 4 patients and preventative in the last 2 patients. Two patients presented hepatic artery thromboses that were solved through an interventional radiologist approach. These patients showed a very high procoagulant state that was observed by thromboelastography. Arterial vasospasm without thrombus was observed in 2 patients during the LT surgery. In order to avoid hepatic artery thrombosis, an arterial conduit from the recipient aorta to the hepatic artery of the donor was used in the fifth patient. After LT, patients presented improvement in propionyl byproducts without complete normalization, but no decompensations have been observed. In conclusion, LT could be a good therapeutic option to improve the metabolic control and the quality of life of PA patients. Improved surgical strategies along with new techniques of interventional radiology allow us to perform the LT minimizing the complications derived from the higher risk of hepatic artery thrombosis.

[Experience with ketogenic diet as treatment for refractory epilepsy]. / Experiencia con la dieta cetogénica como tratamiento en la epilepsia refractaria.

INTRODUCTION: Epilepsy is a disease where most patients have a good control with pharmacological antiepileptic treatment. Nevertheless, 25% of the patients have a refractory epilepsy to usual antiepileptic drugs. Ketogenic diet is one of the treatment options for this type of epilepsy. In spite of the increased popularity of it as an antiepileptic treatment, it does not exist an international consensus of its indications and management. AIM: To evaluate the response, tolerance and adverse effects of the patients with refractory epilepsy at our hospital during the last 20 years. PATIENTS AND METHODS: We reviewed the data of 30 patients with ketogenic diet and the follow-up at the Neurology and Nutrition Services in our Hospital. RESULTS: Ten patients (35.7%) had a positive response with reduction of their seizures for more than six months; five of them had a 50-75% decrease in seizures and five of them had more than 75% of seizure reduction. The most common short term adverse effects were diarrhea, vomiting and hypoglicemia whereas long term adverse effects were constipation and weight gain. CONCLUSIONS: We recommend to use ketogenic diet as treatment in refractory epilepsy since there is a positive response in seizure control in some cases. The adverse effects seen could be prevented or treated without complications. It is a preferable treatment option before using other aggressive therapeutical measures or when surgery is not feasible.