Andreea Nissenkorn

Inborn errors of metabolism: A cause of abnormal brain development

Brain malformations are caused by a disruption in the sequence of normal development by various environmental or genetic factors. By modifying the intrauterine milieu, inborn errors of metabolism may cause brain dysgenesis. However, this association is typically described in single case reports. The authors review the relationship between brain dysgenesis and specific inborn errors of metabolism. Peroxisomal disorders and fatty acid oxidation defects can produce migration defects. Pyruvate dehydrogenase deficiency, nonketotic hyperglycinemia, and maternal phenylketonuria preferentially cause a dysgenetic corpus callosum. Abnormal metabolism of folic acid causes neural tube defects, whereas defects in cholesterol metabolism may produce holoprosencephaly. Various mechanisms have been proposed to explain abnormal brain development in inborn errors of metabolism: production of a toxic or energy-deficient intrauterine milieu, modification of the content and function of membranes, or disturbance of the normal expression of intrauterine genes responsible for morphogenesis. The recognition of a metabolic disorder as the cause of the brain malformation has implications for both the care of the patient and for genetic counseling to prevent recurrence in subsequent pregnancies.

5-ASA and lycopene decrease the oxidative stress and inflammation induced by iron in rats with colitis.

BackgroundSupplementation of 5-aminosalicylic acid (5-ASA) and of iron are among the principal therapies in patients with inflammatory bowel disease. Therapeutic iron, as well as heme iron from chronic mucosal bleeding, can increase iron-mediated oxidative stress in colitis. This study was designed to examine the influence of iron supplementation on histological expression and oxidative status relative to 5-ASA treatment and antioxidant treatment.MethodsColitis was induced using the iodoacetamide rat model, and rats were divided into different dietary groups of 6 rats each: 1, normal chow diet (control); 2, diet supplemented with iron; 3, iron supplementation and lycopene; 4, iron and Β-carotene; 5, 5-ASA; 6, 5-ASA and lycopene; 7, 5-ASA and iron; 8, 5-ASA, iron, and lycopene. The animals were killed after 3 days and the weight of the ulcerated area recorded. Mucosal specimens were histologically evaluated. Myeloperoxidase (MPO) was measured to evaluate inflammatory status (U/g). Malondialdehyde (MDA) was measured in colonic tissue (µmol/g) and superoxide dismutase (SOD) in erythrocytes to assess the degree of tissue oxidative stress.ResultsSignificantly more severe colitis, including necrosis, ulceration, and hemorrhage, was seen in colonic biopsies of rats with colitis when iron was supplemented. This pathology was attenuated when iron was given in combination with 5-ASA and/or lycopene. There was no significant benefit from adding Β-carotene.ConclusionsIron supplementation can amplify the inflammatory response and subsequent mucosal damage in a rat model of colitis. We suggest that the resultant oxidative stress generated by iron supplementation leads to the extension and propagation of crypt abscesses, either through direct membrane disruption by lipid peroxidation or through the generation of secondary toxic oxidants. Simultaneous treatment with 5-ASA and/or lycopene minimizes the potential hazard of iron. Therefore, we suggest giving iron supplementation with 5-ASA or lycopene or both.

Neurologic Presentations of Mitochondrial Disorders

This article describes the neurologic presentations of children with mitochondrial disorders. The charts of 42 children with highly suspect mitochondrial disorders were reviewed. Thirty-seven children were diagnosed as having definite mitochondrial disorders based on a suggestive clinical presentation and at least one accepted criteria, while in five patients the diagnosis remained probable. All patients had nervous system involvement, but it was the presenting symptom in 28 of 42. Eighteen children had normal intelligence and 24 had mental retardation or developmental delay at the onset of their disease. Twenty-five patients had either an acute regression or a progressive encephalopathy. The most frequent neurologic manifestations were abnormal tone, seizures, extrapyramidal movements, and autonomic dysfunction. The eyes were involved in 11 children. Nerve deafness was found in seven patients. Myopathy was found in only six patients. In conclusion, a complex neurologic picture, especially with other organ involvement, warrants a full mitochondrial evaluation. (J Child Neurol 2000; 15:44-48).

Multiple presentation of mitochondrial disorders

The aim of this study was to assess the heterogeneous clinical presentations of children with mitochondrial disorders evaluated at a metabolic neurogenetic clinic. The charts of 36 children with highly suspected mitochondrial disorders were reviewed. Thirty one children were diagnosed as having a mitochondrial disorder, based on a suggestive clinical presentation and at least one of the accepted laboratory criteria; however, in five children with no laboratory criteria the diagnosis remained probable. All of the patients had nervous system involvement. Twenty seven patients also had dysfunction of other systems: sensory organs in 15 patients, cardiovascular system in five, gastrointestinal system in 20, urinary system in four, haematopoietic system in four, and endocrine system in nine. The clinical presentation was compatible with an established syndrome in only 15 children. Severe lactic acidosis or ragged red muscle fibres were encountered in very few patients. These results suggest that mitochondrial disorders should be evaluated in children presenting with a complex neurological picture or multisystem involvement. Key messages A full mitochondrial evaluation is warranted in children with a complex neurological picture or a single neurological symptom and other system involvement When the presentation is classic for a maternally inherited mitochondrial syndrome—for example, mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes (MELAS), myoclonic epilepsy and ragged red muscle fibres (MERRF), Leber’s hereditary optic neuropathy (LHON), appropriate mitochondrial DNA studies should be obtained first When the clinical picture is classic for a nuclear DNA inherited syndrome and the gene or the linkage is known—for example, MNGIE (mitochondrial neurogastrointestinal encephalopathy) or DIDMOAD (diabetes insipidus, diabetes mellitus, optic atrophy, and deafness), proceed with genetic studies When the clinical picture is non-specific but highly suggestive of a mitochondrial disorder, start with serum and/or cerebrospinal fluid lactic acid and urinary organic acids and proceed with muscle biopsy and assessment of the respiratory chain enzymes Normal serum or cerebrospinal fluid lactic acid does not exclude a mitochondrial disorder

Magnetic resonance imaging and magnetic resonance spectroscopy in isolated sulfite oxidase deficiency.

Isolated sulfite oxidase deficiency is a rare genetic neurometabolic disease. The first symptoms of this disorder (similar to symptoms of ischemic events) may lead to misdiagnosis and to subsequent birth of affected children in these families. This study characterizes the magnetic resonance (MR) imaging and (for the first time, to our knowledge) the MR spectroscopy features of isolated sulfite oxidase deficiency to provide a means for early and correct diagnosis. Three patients with isolated sulfite oxidase deficiency are studied who manifested intractable seizures and severe hypotonia in the immediate postnatal period with an unknown diagnosis, despite extensive workup. MR imaging and proton MR spectroscopy examinations were performed early in the neonatal period in 2 infants and after 5 months in the third infant. The prominent MR features were early cystic white matter damage, accompanied by profound cerebral atrophy in the third infant. Compared with hypoxic-ischemic disorder, MR findings in isolated sulfite oxidase deficiency demonstrate a more severe condition, without subsequent recovery. The MR spectroscopy studies indicate early onset of energetic and metabolic imbalance. Urine stick findings demonstrated high sulfite levels in 2 patients, and the final diagnosis was subsequently made based on molecular, biochemical, and genetic findings. Magnetic resonance imaging and MR spectroscopy measurements may help differentiate isolated sulfite oxidase deficiency from hypoxic-ischemic condition in patients in whom this diagnosis is not clinically suspected and may lead to further genetic antenatal inquiry that might prevent the birth of other infants affected with this severe and incurable congenital disease.

Technetium 99m ethylcysteinate dimer single-photon emission computed tomography (SPECT) during intellectual stress test in children and adolescents with pure versus comorbid attention-deficit hyperactivity disorder (ADHD)

Children and adolescents with the Diagnostic and Statistical Manual of Mental Disorders-IV (DSM-IV) diagnosis of attention-deficit hyperactivity disorder (ADHD) can have comorbid conditions such as conduct disorder, oppositional defiant disorder, and obsessive-compulsive disorder (comorbid type). The purpose of our study was to compare the pattern of regional cerebral perfusion in these two groups of children with ADHD during a computerized performance test. Nineteen children and adolescents were enrolled in the study. Seven boys and one girl with pure ADHD (group 1: mean age 12 years, range 9—16 years) and nine boys and two girls with comorbid ADHD (group 2: mean age 11 years, range 8—16 years) were studied by single-photon emission computed tomography (SPECT). The patients were not receiving any medication for at least 48 hours prior to the study. All patients were injected with 99mTc- ethylcysteinate dimer while doing a computerized performance test. Nine age-matched control children (five boys and four girls, mean age 12 years, range 9—17 years) with a normal brain SPECT served as controls. All patients in group 2 showed significantly decreased perfusion in the temporal lobes (P < .005). Five patients had decreased frontal lobe perfusion. Additionally, two patients in group 2 had decreased perfusion in the basal ganglia (not significant). Four of eight patients in group 1 had decreased frontal lobe perfusion (not significant). In addition, two patients had bilateral temporal lobe abnormalities, whereas two patients had a normal SPECT. Three patients in group 1 also had decreased basal ganglia perfusion. In contrast to previous studies of brain perfusion in ADHD that focused mainly on frontal and prefrontal cortical abnormalities, our study demonstrates that temporal lobe perfusion abnormalities are more common in patients with the comorbid type of ADHD. We postulate that these findings can have therapeutic implications and explain the decreased response to stimulants in this group of patients. (J Child Neurol 2004; 19: 91—96).

Liver Disease in Pediatric Patients With Ataxia Telangiectasia: A Novel Report.

Objective: Ataxia telangiectasia (A-T) is a rare genetic multiorgan disease. Although gastrointestinal involvement is known, hepatic involvement in A-T has not been investigated. We aimed to study the hepatic involvement in a large cohort of patients with A-T. Methods: A retrospective review of patients, studied from January 1986 to January 2015 at a National A-T Center. Clinical data including demographic, genetic, laboratory, nutritional, radiographic, and histological data were retrieved. Results: Fifty-three patients, 27 (49%) boys, age 14.6 ± 5.2 years (range 5.9–26.1 years), were included. Twenty-three patients (43.4%), age 9.9 ± 5.1 years, had consistently abnormal liver enzymes. The mean enzyme levels were alanine aminotransferase 76.8 ± 73.8 IU/L, aspartate aminotransferase 70 ± 50 IU/L, alkaline phosphatase 331 ± 134 IU/L, and gamma glutamyl transferase 114.7 ± 8 IU/L. Evaluation of other etiology of liver disease was negative. Ultrasonography revealed fatty liver in 9 of them (39%). Liver biopsy was performed in 2 patients, revealing mild-to-moderate steatosis in both, and fibrosis in 1 patient. Progression to advanced liver disease occurred in 2 of 23 (9%) patients within 2 to 5 years. Dyslipidemia was significantly associated with abnormal liver enzymes: 3 of 30 (10%) patients without abnormal liver enzymes versus 10 of 23 (45.5%) patients with abnormal liver enzymes, respectively (P < 0.05, Fisher exact test). No correlation was found between hepatic involvement and HbA1C, sex, presence of malignancy, or type of mutation. Conclusions: Abnormal liver enzymes and fatty liver are common in patients with A-T and may progress to advanced liver disease at a young age. These findings are novel and implicate that patients with A-T with abnormal liver enzymes should be evaluated for the presence of liver disease.

Muscle Glycogen Depletion and Increased Oxidative Phosphorylation Following Status Epilepticus

We describe complete glycogen depletion and increased respiratory chain enzyme activity in a muscle biopsy obtained prior to the demise of a patient in multiorgan failure following status epilepticus. These findings validate the theoretical basis of muscle energy turnover during status epilepticus: the increased demand for energy leads to complete depletion of glycogen reserves. The attempt to preserve adenosine triphosphate requirements results in increased activity of respiratory chain enzymes. (J Child Neurol 2003;18: 876-877).