Sarah Grünert

Sarah Grünert
University Medical Center Freiburg · Center for Paediatric and Adolescent Medicine

MD

About

134
Publications
26,014
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
2,162
Citations
Introduction
Skills and Expertise

Publications

Publications (134)
Article
Newborn screening (NBS) for inherited metabolic diseases (IMDs) substantially shortens a patient’s journey. It enables the early start of metabolic treatment which might prevent potentially lethal neonatal disease manifestations, while promoting favorable development and long-term clinical outcomes. This study aims to assess growth in screened indi...
Article
Glycerol phenylbutyrate (GPB) is an ammonia scavenger drug commonly used in the therapy of patients with urea cycle defects. Reported side effects include body odor, abdominal pain, nausea, burning sensation in mouth, vomiting, and heartburn. We report on a 3‐year‐old late diagnosed female patient with ornithine transcarbamylase deficiency that exp...
Article
Full-text available
Methionine adenosyltransferase I/III deficiency is an inborn error of metabolism due to mutations in the MAT1A gene. It is the most common cause of hypermethioninemia in newborn screening. Heterozygotes are often asymptomatic. In contrast, homozygous or compound heterozygous individuals can develop severe neurological symptoms. Less than 70 cases w...
Article
Full-text available
Background: Living with a non-acute (phenylketonuria) or acute (e.g. urea cycle disorders, organic acidurias) intoxication-type inborn error of metabolism (IT-IEM) can have a substantial impact on health-related quality of life (HrQoL) of paediatric patients and their families. Parents take primary responsibility for treatment monitoring and exper...
Article
Purpose: This paper aims to report collective information on safety and efficacy of empagliflozin drug repurposing in individuals with glycogen storage disease type Ib (GSD Ib). Methods: This is an international retrospective questionnaire study on the safety and efficacy of empagliflozin use for management of neutropenia/neutrophil dysfunction...
Article
Full-text available
Glycogen storage disease type Ib (GSD Ib) is caused by biallelic variants in SLC37A4. GSD Ib is characterized by hepatomegaly, recurrent hypoglycemia, neutropenia, and neutrophil dysfunction. Only seven pregnancies in four women with GSD Ib have been reported so far. We report on two further successful pregnancies in two patients with GSD Ib. One o...
Article
Full-text available
S-adenosylmethionine (SAM) is essential for methyl transfer reactions. All SAM is produced de novo via the methionine cycle. The demethylation of SAM produces S-adenosylhomocysteine (SAH), an inhibitor of methyltransferases and the precursor of homocysteine (Hcy). The measurement of SAM and SAH in plasma has value in the diagnosis of inborn errors...
Article
Full-text available
Axonal peripheral neuropathy is a common complication of mitochondrial trifunctional protein (MTP) deficiency and long‐chain 3‐hydroxyacyl‐CoA dehydrogenase deficiency that is usually considered progressive. Current treatment strategies are not able to fully prevent neuropathic symptoms in the majority of patients. We herein report three sisters wi...
Article
Full-text available
Background Glycogen storage disease type I (GSD I) is a rare autosomal recessive disorder of carbohydate metabolism characterized by recurrent hypoglycaemia and hepatomegaly. Management of GSD I is demanding and comprises a diet with defined carbohydrate intake and the use of complex carbohydrates, nocturnal tube feeding or night-time uncooked corn...
Article
Full-text available
Fanconi-Bickel syndrome (FBS) is a very rare but distinct clinical entity with the combined features of hepatic glycogen storage disease, generalized proximal renal tubular dysfunction with disproportionately severe glucosuria, and impaired galactose tolerance. Here, we report five cases (out of 93 diagnosed in our lab) with pathogenic variants on...
Article
Full-text available
Glycogen storage disease type Ia (GSDIa) is caused by defective glucose-6-phosphatase, a key enzyme in carbohydrate metabolism. Affected individuals cannot release glucose during fasting and accumulate excess glycogen and fat in the liver and kidney, putting them at risk of severe hypoglycaemia and secondary metabolic perturbations. Good glycaemic/...
Article
Full-text available
The aim of the study was a systematic evaluation of cognitive development in individuals with glutaric aciduria type 1 (GA1), a rare neurometabolic disorder, identified by newborn screening in Germany. This national, prospective, observational, multi-centre study includes 107 individuals with confirmed GA1 identified by newborn screening between 19...
Article
Full-text available
Medium-chain fatty acids (mc-FAs) are currently applied in the treatment of long-chain fatty acid oxidation disorders (lc-FAOD) characterized by impaired β-oxidation. Here, we performed lipidomic and proteomic analysis in fibroblasts from patients with very long-chain acyl-CoA dehydrogenase (VLCADD) and long-chain 3-hydroxyacyl-CoA dehydrogenase (L...
Article
Full-text available
Patients with inborn errors of metabolism causing fasting intolerance can experience acute metabolic decompensations. Long-term data on outcomes using emergency letters are lacking. This is a retrospective, observational, single-center study of the use of emergency letters based on a generic emergency protocol in patients with hepatic glycogen stor...
Article
Full-text available
Glycogen storage disease type VI (GSD VI) is an autosomal recessive disorder of glycogen metabolism due to mutations in the glycogen phosphorylase gene (PYGL), resulting in a deficiency of hepatic glycogen phosphorylase. We performed a systematic literature review in order to collect information on the clinical phenotypes and genotypes of all publi...
Article
Full-text available
Background and Aims Glycogen storage disease type I (GSD I) is associated with hyperlipidemia, a known risk factor for premature atherosclerosis. Few studies have addressed endothelial dysfunction in patients with GSD I, and these studies yielded controversial results. Methods and Results We investigated vascular dysfunction in a cohort of 32 pati...
Article
Full-text available
Continuous glucose monitoring (CGM) systems are of great value for patients with disorders of impaired glucose homeostasis, including glycogen storage diseases. We report on an 8‐year‐old girl with glycogen storage disease type 9b who developed severe allergic contact dermatitis to two different continuous glucose monitoring systems, FreeStyle® Lib...
Article
Full-text available
Autosomal recessive Chanarin-Dorfman syndrome (CDS, MIM #275630) is defined as a neutral lipid storage disease with ichthyosis (NLSDI) due to an accumulation of lipid droplets in a variety of different tissues including liver and muscle cells, leucocytes, fibroblasts and nerve cells It is caused by biallelic mutations in the abhydrolase domain cont...
Article
Full-text available
Propionic aciduria (PA) is caused by deficiency of the mitochondrial enzyme propionyl-CoA carboxylase (PCC). Due to inefficient propionate catabolism patients are endangered by life-threatening ketoacidotic crisis. Protein and amino acid restriction are major therapeutic pillars. However, long-term complications like neurological deterioration and...
Article
Full-text available
Vertebral, Cardiac, Renal and Limb Defect Syndrome (VCRL), is a very rare congenital malformation syndrome. Pathogenic variants in HAAO (3-Hydroxyanthranilate 3,4-dioxygenase), NADSYN1 (NAD+ Synthetase-1) and KYNU (Kynureninase) have been identified in a handful of affected individuals. All three genes encode for enzymes essential for the NAD+ de n...
Article
Full-text available
Glycogen storage disease type VI is caused by biallelic variants in the PYGL gene that result in hepatic glycogen phosphorylase deficiency. The disorder is clinically characterized by hepatomegaly and recurrent ketotic hypoglycemia from infancy. Although most patients reach adulthood without major complications, no pregnancies in women with GSD VI...
Article
Full-text available
Long-chain fatty acid oxidation disorders (lc-FAOD) are a group of diseases affecting the degradation of long-chain fatty acids. In order to investigate the disease specific alterations of the cellular lipidome, we performed undirected lipidomics in fibroblasts from patients with carnitine palmitoyltransferase II, very long-chain acyl-CoA dehydroge...
Article
Full-text available
Hypomethylation of H19 and IGF2 can cause Silver-Russell syndrome (SRS), a clinically and genetically heterogeneous condition characterized by intrauterine growth restriction, poor postnatal growth, relative macrocephaly, craniofacial abnormalities, body asymmetry, hypoglycemia and feeding difficulties. Isolated hypomethylation of IGF2 has been rep...
Preprint
Full-text available
Background Glycogen storage disease type I (GSD I) is a rare autosomal recessive disorder of carbohydate metabolism characterized by recurrent hypoglycaemia and hepatomegaly. Management of GSD I is demanding and comprises a diet with defined carbohydrate intake and the use of complex carbohydrates, nocturnal tube feeding or night-time uncooked corn...
Article
Full-text available
Background Childhood hypoglycemia in combination with hepatomegaly is suspicious for inborn errors of metabolism. Cystic fibrosis typically presents with failure to thrive, pulmonary and gastrointestinal symptoms. Hepatic involvement and hypoglycemia can occur in a significant number of patients, although hepatomegaly is uncommon. Case presentatio...
Preprint
Full-text available
Background Glycogen storage disease type Ib (GSD Ib) due to biallelic mutations in SLC37A4 is often associated with inflammatory bowel disease. Peritoneal inclusion cysts (PICs) are variable sized, fluid-filled, mesothelial-lined cysts that usually occur in premenopausal woman. Risk factors for the development of PICS comprise prior abdominal surge...
Article
Full-text available
Introduction Patients with inborn errors of metabolism causing fasting intolerance can experience acute metabolic decompensations. Long‐term data on outcomes using emergency letters are lacking. Methods This is a retrospective, observational, single‐center study of the use of emergency letters based on a generic emergency protocol in patients with...
Article
Full-text available
Introduction: Glycogen storage disease type VI (GSD VI) is a disorder of glycogen metabolism due to mutations in the PYGL gene. Patients with GSD VI usually present with hepatomegaly, recurrent hypoglycemia, and short stature. Results: We report on two non-related Turkish patients with a novel homozygous splice site variant, c.345G>A, which was...
Article
Full-text available
Fabry disease (FD) is an X‐linked lysosomal storage disorder. Deficiency of the lysosomal enzyme alpha‐galactosidase (GLA) leads to accumulation of potentially toxic globotriaosylceramide (Gb3) on a multisystem level. Cardiac and cerebrovascular abnormalities as well as progressive renal failure are severe, life‐threatening long‐term complications....
Article
Peripheral neuropathy is a known long‐term, irreversible complication of long‐chain 3‐hydroxyacyl‐CoA dehydrogenase deficiency (LCHADD) and mitochondrial trifunctional protein deficiency (MTPD), two inherited disorders of mitochondrial long‐chain fatty acid oxidation. The underlying pathophysiology of neuropathy is still not fully understood. We re...
Article
Full-text available
Isolated methylmalonic acidaemia (MMA) and propionic acidaemia (PA) are rare inherited metabolic diseases. Six years ago, a detailed evaluation of the available evidence on diagnosis and management of these disorders has been published for the first time. The article received considerable attention, illustrating the importance of an expert panel to...
Article
Full-text available
Medium‐chain acyl‐CoA dehydrogenase deficiency (MCADD) is the most common defect of mitochondrial β‐oxidation. Confirmation diagnostics after newborn screening (NBS) can be performed either by enzyme testing and/ or by sequencing of the ACADM gene. Here, we report the results from enzyme testing in lymphocytes with gene variants from molecular anal...
Article
Objective To evaluate the clinical outcomes at age 1.5± 0.5 years of infants with vitamin B12 deficiency identified by newborn screening (NBS). Study design Prospective multi-center observational study on health outcomes of 31 infants with vitamin B12 deficiency identified by NBS. Neurodevelopment was assessed by Denver Developmental Screening Tes...
Article
Succinyl-CoA:3-oxoacid coenzyme A transferase deficiency (SCOTD) is a rare autosomal recessive disorder of ketone body utilization caused by mutations in OXCT1. We performed a systematic literature search and evaluated clinical, biochemical and genetic data on 34 previously published and 10 novel patients with SCOTD. Structural mapping and in silic...
Article
Objective Isovaleric aciduria (IVA), a metabolic disease with severe (classic IVA) or attenuated phenotype (mild IVA), is included in newborn screening (NBS) programs worldwide. The long‐term clinical benefit of screened individuals, however, is still rarely investigated. Methods National, prospective, observational, multi‐centre study of individu...
Article
Full-text available
Glutaric aciduria type 1 (GA1) is a rare neurometabolic disorder, caused by inherited deficiency of glutaryl‐CoA dehydrogenase, mostly affecting the brain. Early identification by newborn screening (NBS) significantly improves neurologic outcome. It has remained unclear whether recommended therapy, particular low lysine diet, is safe or negatively...
Article
Full-text available
Background: 3-hydroxy-3-methylglutaryl-coenzyme A lyase deficiency (HMGCLD) is an autosomal recessive disorder of ketogenesis and leucine degradation due to mutations in HMGCL. Method: We performed a systematic literature search to identify all published cases. Two hundred eleven patients of whom relevant clinical data were available were includ...
Article
Full-text available
Background: Primary carnitine deficiency due to mutations in the SLC22A5 gene is a rare but well-treatable metabolic disorder that puts patients at risk for metabolic decompensations, skeletal and cardiac myopathy and sudden cardiac death. Results: We report on a 7-year-old boy diagnosed with primary carnitine deficiency 2 years after successful...
Article
Full-text available
Background: 2-methylacetoacetyl-coenzyme A thiolase deficiency (MATD; deficiency of mitochondrial acetoacetyl-coenzyme A thiolase T2/ "beta-ketothiolase") is an autosomal recessive disorder of ketone body utilization and isoleucine degradation due to mutations in ACAT1. Methods: We performed a systematic literature search for all available clini...
Article
Full-text available
Background: Glycogen storage disease type Ib (GSD Ib) is a rare inborn error of glycogen metabolism due to mutations in SLC37A4. Besides a severe form of fasting intolerance, the disorder is usually associated with neutropenia and neutrophil dysfunction causing serious infections, inflammatory bowel disease, oral, urogenital and perianal lesions a...
Article
Full-text available
Background Neonatal intrahepatic cholestasis caused by citrin deficiency (CD) is a rare inborn error of metabolism due to variants in the SLC25A13 gene encoding the calcium-binding protein citrin. Citrin is an aspartate-glutamate carrier located within the inner mitochondrial membrane. Case presentation We report on two siblings of Romanian-Vietna...
Article
Full-text available
Glycogen storage disease subtypes I and III (GSD I and GSD III) are monogenic inherited disorders of metabolism that disrupt glycogen metabolism. Unavailability of glucose in GSD I and induction of gluconeogenesis in GSD III modify energy sources and possibly, mitochondrial function. Abnormal mitochondrial structure and function were described in m...
Article
Background: Although extended newborn screening (NBS) programs have been introduced more than 20 years ago, their impact on the long-term clinical outcome of individuals with inherited metabolic diseases (IMDs) is still rarely investigated. Methods: We studied the clinical outcomes of individuals with IMDs identified by NBS between 1999 and 2016...
Article
Episodic encephalopathy due to mutations in the thiamine pyrophosphokinase 1 (TPK1) gene is a rare autosomal recessive metabolic disorder. Patients reported so far have onset in early childhood of acute encephalopathic episodes, which result in a progressive neurologic dysfunction including ataxia, dystonia, and spasticity. Here, we report the case...
Article
Full-text available
Glycogen storage disease type 0 (GSD 0) is a rare inborn error of metabolism due to deficiency of the enzyme glycogen synthase (EC 2.4.1.11). The disorder is clinically characterized by ketotic fasting hypoglycemia in combination with postprandial hyperglycemia and hyperlactatemia. So far, only one pregnancy has been described in a woman with GSD 0...
Article
Quantitative estimates for the global impact of COVID-19 on the diagnosis and management of patients with inborn errors of metabolism (IEM) are lacking. We collected relevant data from 16 specialized medical centers treating IEM patients in Europe, Asia and Africa. The median decline of reported IEM related services in March 1st-May 31st 2020 compa...
Preprint
Full-text available
Background Glycogen storage disease type 0 (GSD 0) is a rare inborn error of metabolism due to deficiency of the enzyme glycogen synthase (EC 2.4.1.11). Patients with this disorder are unable to store glucose as glycogen in the liver. GSD 0 is therefore characterized by ketotic fasting hypoglycemia in combination with postprandial hyperglycemia and...
Preprint
Full-text available
Background Neonatal intrahepatic cholestasis caused by citrin deficiency (CD) is a rare inborn error of metabolism due to variants in the SLC25A13 gene encoding the calcium-binding protein citrin. Citrin is an aspartate-glutamate carrier located within the inner mitochondrial membrane. Results We report on two siblings of Romanian-Vietnamese ancest...
Article
Full-text available
Background: Hepatic glycogen storage diseases (GSDs) are inborn errors of metabolism affecting the synthesis or breakdown of glycogen in the liver. This study, for the first time, systematically assessed vitamin B12 status in a large cohort of hepatic GSD patients. Methods: Plasma vitamin B12, total plasma homocysteine (tHcy) and methylmalonic acid...
Preprint
Full-text available
Background Glycogen storage disease type Ib (GSD Ib) is a rare inborn error of glycogen metabolism due to mutations in SLC37A4. Besides a severe form of fasting intolerance, the disorder is usually associated with neutropenia and neutrophil dysfunction causing serious infections, inflammatory bowel disease, oral, urogenital and perianal lesions as...
Article
Full-text available
3‐Hydroxy‐3‐methylglutaryl‐coenzyme A lyase deficiency (HMGCLD) is a rare autosomal recessively inherited metabolic disorder. Patients suffer from avoidable neurologically devastating metabolic decompensations and thus would benefit from newborn screening (NBS). The diagnosis is currently made by measuring dry blood spot acylcarnitines (C5OH and C6...
Article
Full-text available
Background: Inborn errors of metabolism (IEM) are a group of rare, heterogeneous and complex genetic conditions. Clinically, IEM often affect the central nervous system and other organs. Some carry the risk of progression and / or potentially life-threatening crises. Many patients have to adhere to lifelong dietary or drug treatment. The complexit...
Article
Introduction: Pearson syndrome (PS) was originally reported as a sideroblastic anemia in infancy with vacuolization of marrow precursors and exocrine pancreas dysfunction. It is now recognized as a fatal multisystem mitochondrial disorder caused by single mitochondrial DNA deletions (SLSMDs) presenting with anemia. PS, Kearns-Sayre Syndrome (KSS) a...
Article
Full-text available
The concentration of thiol and thioether metabolites in plasma has diagnostic value in genetic diseases of B-vitamin metabolism linked to methionine utilization. Among these, cysteine/cystine (Cys/CSSC) and glutathione/oxidized glutathione (GSH/GSSG) act as cellular redox buffers. A new LC-MS/MS method was developed for the simultaneous detection o...
Article
Full-text available
Primary mitochondrial disease (PMD) is a large group of genetic disorders directly affecting mitochondrial function. Although next generation sequencing technologies have revolutionized the diagnosis of these disorders, biochemical tests remain essential and functional confirmation of the critical genetic diagnosis. While enzymological testing of t...
Article
Full-text available
Background: PMM2-CDG (Phosphomannomutase 2 - Congenital disorder of glycosylation-Ia; CDG-Ia) is the most common glycosylation defect, often presenting as a severe multisystem disorder that can be fatal within the first years of life. While mannose treatment has been shown to correct glycosylation in vitro and in vivo in mice, no convincing effect...
Article
Full-text available
Transport And Golgi Organization protein 2 (TANGO2) deficiency has recently been identified as a rare metabolic disorder with a distinct clinical and biochemical phenotype of recurrent metabolic crises, hypoglycemia, lactic acidosis, rhabdomyolysis, arrhythmias, and encephalopathy with cognitive decline. We report nine subjects from seven independe...
Article
Carnitine palmitoyltransferase II (CPT2) is a rare autosomal recessive inherited disorder affecting mitochondrial β‐oxidation. Confirmation diagnostics are mostly based on molecular sequencing of the CPT2 gene, especially to distinguish CPT2 and carnitine aclycarnitine translocase (CACT) deficiencies, which present with identical acylcarnitine prof...