Genome and RNA sequencing were essential to reveal cryptic intronic variants associated to defective ATP6AP1 mRNA processing.

The diagnosis of Mendelian disorders has notably advanced with integration of whole exome and genome sequencing (WES and WGS) in clinical practice. However, challenges in variant interpretation and uncovered variants by WES still leave a substantial percentage of patients undiagnosed. In this context, integrating RNA sequencing (RNA-seq) improves diagnostic workflows, particularly for WES inconclusive cases. Additionally, functional studies are often necessary to elucidate the impact of prioritized variants on gene expression and protein function. Our study focused on three unrelated male patients (P1-P3) with ATP6AP1-CDG (congenital disorder of glycosylation), presenting with intellectual disability and varying degrees of hepatopathy, glycosylation defects, and an initially inconclusive diagnosis through WES. Subsequent RNA-seq was pivotal in identifying the underlying genetic causes in P1 and P2, detecting ATP6AP1 underexpression and aberrant splicing. Molecular studies in fibroblasts confirmed these findings and identified the rare intronic variants c.289-233C > T and c.289-289G > A in P1 and P2, respectively. Trio-WGS also revealed the variant c.289-289G > A in P3, which was a de novo change in both patients. Functional assays expressing the mutant alleles in HAP1 cells demonstrated the pathogenic impact of these variants by reproducing the splicing alterations observed in patients. Our study underscores the role of RNA-seq and WGS in enhancing diagnostic rates for genetic diseases such as CDG, providing new insights into ATP6AP1-CDG molecular bases by identifying the first two deep intronic variants in this X-linked gene. Additionally, our study highlights the need to integrate RNA-seq and WGS, followed by functional validation, in routine diagnostics for a comprehensive evaluation of patients with an unidentified molecular etiology.

Preparing Enteral Formulas for Adult Patients with Phenylketonuria: A Minor Necessity but Major Challenge-A Case Report.

Phenylketonuria (PKU) is the most frequent of the congenital errors of amino acid (AA) metabolism worldwide. It leads to the accumulation of the essential AA phenylalanine (Phe) and it is associated with severe neurological defects. The early diagnosis and treatment of this rare disease, achieved through newborn screening and low-Phe diet, has profoundly changed its clinical spectrum, resulting in normal cognitive development. We face the first generation of PKU patients perinatally diagnosed and treated who have reached adulthood, whose special needs must be addressed, including feeding through enteral nutrition (EN). However, recommendations regarding EN in PKU constitute a gap in the literature. Although protein substitutes for patients with PKU are offered in multiple forms (Phe-free L-amino acid or casein glycomacropeptide supplements), none of these commercial formulas ensures the whole provision of daily total energy and protein requirements, including a safe amount of Phe. Consequently, the combination of different products becomes necessary when artificial nutrition via tube feeding is required. Importantly, the composition of these specific formulas may result in physicochemical interactions when they are mixed with standard EN products, leading to enteral feeding tubes clogging, and also gastrointestinal concerns due to hyperosmolality. Herein, we present the first reported case of EN use in an adult patient with PKU, where the separate administration of protein substitutes and the other EN products avoided physicochemical interactions.

Lysinuric Protein Intolerance and Its Nutritional and Multisystemic Challenges in Pregnancy: A Case Report and Literature Review.

Lysinuric protein intolerance (LPI) is a rare inborn error of metabolism (IEM), classified as an inherited aminoaciduria, caused by mutations in the SLC7A7 gene, leading to a defective cationic amino acid transport. The metabolic adaptations to the demands of pregnancy and delivery cause significant physiological stress, so those patients affected by IEM are at greater risk of decompensation. A 28-year-old woman with LPI had experienced 3 early miscarriages. While pregnancy was finally achieved, diverse nutritional and medical challenges emerged (food aversion, intrauterine growth restriction, bleeding risk, and preeclampsia suspicion), which put both the mother and the fetus at risk. Moreover, the patient requested a natural childbirth (epidural-free, delayed cord clamping). Although the existence of multiple safety concerns rejected this approach at first, the application of novel strategies made a successful delivery possible. This case reinforces that the woman's wish for a non-medicated, low-intervention natural birth should not be automatically discouraged because of an underlying complex metabolic condition. Achieving a successful pregnancy is conceivable thanks to the cooperation of interdisciplinary teams, but it is still important to consider the risks beforehand in order to be prepared for possible additional complications.

Switching to Glycerol Phenylbutyrate in 48 Patients with Urea Cycle Disorders: Clinical Experience in Spain.

Background and objectives: Glycerol phenylbutyrate (GPB) has demonstrated safety and efficacy in patients with urea cycle disorders (UCDs) by means of its clinical trial program, but there are limited data in clinical practice. In order to analyze the efficacy and safety of GPB in clinical practice, here we present a national Spanish experience after direct switching from another nitrogen scavenger to GPB. Methods: This observational, retrospective, multicenter study was performed in 48 UCD patients (age 11.7 ± 8.2 years) switching to GPB in 13 centers from nine Spanish regions. Clinical, biochemical, and nutritional data were collected at three different times: prior to GPB introduction, at first follow-up assessment, and after one year of GPB treatment. Number of related adverse effects and hyperammonemic crisis 12 months before and after GPB introduction were recorded. Results: GPB was administered at a 247.8 ± 102.1 mg/kg/day dose, compared to 262.6 ± 126.1 mg/kg/day of previous scavenger (46/48 Na-phenylbutyrate). At first follow-up (79 ± 59 days), a statistically significant reduction in ammonia (from 40.2 ± 17.3 to 32.6 ± 13.9 µmol/L, p < 0.001) and glutamine levels (from 791.4 ± 289.8 to 648.6 ± 247.41 µmol/L, p < 0.001) was observed. After one year of GPB treatment (411 ± 92 days), we observed an improved metabolic control (maintenance of ammonia and glutamine reduction, with improved branched chain amino acids profile), and a reduction in hyperammonemic crisis rate (from 0.3 ± 0.7 to less than 0.1 ± 0.3 crisis/patients/year, p = 0.02) and related adverse effects (RAE, from 0.5 to less than 0.1 RAEs/patients/year p < 0.001). Conclusions: This study demonstrates the safety of direct switching from other nitrogen scavengers to GPB in clinical practice, which improves efficacy, metabolic control, and RAE compared to previous treatments.

Clinical characteristics and outcome of patients aged over 80 years with covid-19.

ABSTRACT: To investigate the clinical characteristics and outcome of octogenarians with covid-19.This is a observational, retrospective, descriptive study.Consecutive patients aged >80 years who were admitted for covid-19 pneumonia during a 6 weeks period (March 20-April 30, 2020).Illness severity on admission was classified according to World Health Organization (WHO) criteria: mild, moderate, severe, and critical. Data collected included demographics, presenting symptoms, radiological and laboratory findings, comorbidities, functional status, treatment, and clinical outcome.There were 159 patients (52.2% women) with a median age of 85.99 (IQR: 80-98). The median Barthel index was 90 (40-100) and Charlson index was 5 (5-6). Most common presenting symptoms were fever, dyspnea, and cough. Patients had mild (8.2%), moderate (52.2%), or severe (39.6%) illness according to WHO criteria. A bilateral pulmonary involvement was seen in 86% of patients. Laboratory analysis revealed increased serum concentrations of inflammatory parameters (C-reactive protein, ferritin, lactate dehydrogenase, and D-dimer) with an abnormal lymphocyte count [0.88 × 109/L (0.5)]. Treatments included corticosteroids in 37%, and biological therapies in 17.6%. Fifty three (33.3%) patients died during hospitalization, with a median time from admission to death of 3 (IQR 1-6) days. Mortality was higher in men (55%). Deceased patients had a significantly higher frequency of dyspnea, increased inflammatory parameters, and illness severity compared to survivors.One-third of octogenarians with covid-19 died during hospitalization and most had bilateral lung involvement. A further knowledge of the characteristics and outcome of this population may assist clinicians in the decision-making process in these patients.