Tuba F. Eminoglu

Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE): case report with a new mutation

IntroductionMitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is a rare autosomal recessive multisystem disorder characterized by severe gastrointestinal dysmotility and leads to cachexia, ptosis, external ophthalmoplegia, peripheral neuropathy, and leukoencephalopathy.Results and discussionIt is often misdiagnosed as anorexia nervosa or intestinal pseudoobstuctions and are unnecessarily treated with surgery. It has been established that MNGIE is caused by mutations in the gene encoding thymidine phosphorylase, which lead to absolute or nearly complete loss of its catalytic activity, producing systemic accumulations of its substrates, thymidine and deoxyuridine.ConclusionWe present herein the clinical, neuroimaging, and molecular findings of a patient with MNGIE caused by a novel homozygous TYMP gene mutation (c.112G>T which convert codon 38 from glutamate to a stop codon [p.38E>X]).

Quality of life in children treated with restrictive diet for inherited metabolic disease

The aim of this study was to investigate the quality of life (QoL) of a group of patients with inherited metabolic diseases (IMD) who were treated with restrictive diet.

Very long-chain acyl CoA dehydrogenase deficiency which was accepted as infanticide.

Very-long-chain acyl-coenzyme A (CoA) dehydrogenase deficiency (VLCADD) (OMIM #201475) is an autosomal recessive disorder of fatty acid oxidation. Major phenotypic expressions are hypoketotic hypoglycemia, hepatomegaly, cardiomyopathy, myopathy, rhabdomyolysis, elevated creatinine kinase, and lipid infiltration of liver and muscle. At the same time, it is a rare cause of Sudden Infant Death Syndrome (SIDS) or unexplained death in the neonatal period [1-4]. We report a patient with VLCADD whose parents were investigated for infanticide because her three previous siblings had suddenly died after normal deliveries.

The Janus-faced manifestations of homozygous familial hypobetalipoproteinemia due to apolipoprotein B truncations

Familial hypobetalipoproteinemia is a codominant disorder characterized by low plasma levels of low-density lipoprotein cholesterol and apolipoprotein B (apoB), which in ∼50% of the cases is due to mutations in APOB gene. In most cases, these mutations cause the formation of truncated apoBs of various sizes, which have a reduced capacity to bind lipids and form lipoprotein particles. Here, we describe 2 children with severe hypobetalipoproteinemia found to be homozygous for novel APOB gene mutations. The first case (HBL-201) was an asymptomatic 13-year-old boy incidentally found to have slightly elevated serum transaminases associated with hepatic steatosis. He was homozygous for a truncated apoB (2211 amino acids, apoB-48.74) whose size is similar to that of wild-type apoB-48 (2152 amino acids) produced by the intestine. ApoB-48.74 is expected to be incorporated into chylomicrons in the intestine but might have a reduced capacity to form secretion-competent very low-density lipoprotein in the liver. The second patient (HBL-96) was a 6-month-old girl suspected to have abetalipoproteinemia, for the presence of chronic diarrhea, failure to thrive, extremely severe hypobetalipoproteinemia, and low plasma levels of vitamin E and vitamin A. She was homozygous for a nonsense mutation (Gln513*) resulting in a short truncated apoB (apoB-11.30), which is not secreted into the plasma. In this patient, the impaired chylomicron formation is responsible for the severe clinical manifestations and growth retardation. In homozygous familial hypobetalipoproteinemia, the capacity of truncated apoBs to form chylomicrons is the major factor, which affects the severity of the clinical manifestations.

Rapid screening of 12 common mutations in Turkish GSD 1a patients using electronic DNA microarray.

Glycogen storage disease type Ia (GSD Ia) is an autosomal recessive disorder caused by mutations in the G6PC gene encoding glucose-6-phosphatase (G6Pase), a key enzyme for the maintenance of glucose homeostasis. Molecular analysis is a reliable and accurate way of diagnosing GSD Ia without to need for invasive liver biopsies for enzyme tests. In some ethnic groups and geographic regions, allelic homogeneity was detected in GSD Ia. In the present study, the most common 12 mutations in the world were searched by microelectronic array technology, a new method, in 27 Turkish patients diagnosed for GSD Ia and the relation between detected mutations and clinical and laboratory findings was investigated. Mutations causing the disease were detected in 45 (83.3%) of 54 alleles screened in the cases with GSD Ia. Allelic frequency of mutations (p.R83C, p.G270V, p.G188R, p.W77R) looked for were found as 68.5%, 7.4%, 3.7%, and 3.7%, respectively. p.G188R mutation was detected for the first time in a patient of Turkish origin. Eight (p.R170Q, p.Q347X, c.79delC, c.380_381insTA, p.D38V, p.W63X, c.648G>T, c.979_981delTTC) of 12 mutations looked for were coincided in none of the patients. The patient with homozygous p.W77R mutation seemed to present milder clinical and laboratory findings, compared to other patients. In conclusion, we suggest that microarray technology, which allows rapid analysis of frequently detected mutations and has considerably lower costs than other methods, can be successfully used in diagnosis of GSD Ia in populations with allelic homogeneity, such as patients of Turkish origin, instead of screening the whole gene.

Lipid apheresis applications in childhood: Experience in the University Hospital of Gazi

The most commonly encountered complications in familial hypercholesterolemia (FH) are mainly cardiovascular in origin and the majority of cases unfortunately die due to this problem. LDL-apheresis is a proven therapeutic method in lowering this mortal risk. In this study we aimed to demonstrate the efficiency of LDL-apheresis performed by DALI or Cascade filtration on four pediatric patients with the diagnosis of homozygous FH. Applied LDL-apheresis techniques, side effects, laboratory results and cardiovascular follow-up are discussed in the light of current literature. Our study has shown once again that lipid apheresis treatment in children with homozygous FH is the most effective treatment. The number of childhood subjects in whom lipid apheresis is performed is quite insufficient. There are no studies that compare DALI with cascade filtration in childhood subjects in our knowledge. The view of this aspect, this study will contribute to literature.