An Unusual Presentation of Hemorrhagic Disease in an Infant: A Probable Case of Abetalipoproteinemia.

We report a probable case of abetalipoproteinemia in an infant who presented with unusual symptoms of late-onset vitamin K deficiency. Abetalipoproteinemia is a rare autosomal recessive disease caused by mutation of the microsomal triglyceride transfer protein gene, resulting in the absence of microsomal triglyceride transfer protein function in the small bowel. It is characterized by the absence of plasma apolipoprotein B-containing lipoproteins, fat malabsorption, hypocholesterolemia, retinitis pigmentosa, progressive neuropathy, myopathy, and acanthocytosis. A biopsy of the small intestine characteristically shows marked lipid accumulation in the villi of enterocytes. Large supplements of fat-soluble vitamins A, D, E, and K have been shown to limit neurologic and ocular manifestations. Dietary fat intake is limited to medium-chain triglycerides.

Novel MTTP Gene Mutation in a Case of Abetalipoproteinemia with Central Hypothyroidism

Abetalipoproteinaemia (ABL) is an autosomal recessive disorder characterized by very low plasma concentrations of total cholesterol and triglyceride (TG). It results from mutations in the gene encoding microsomal TG transfer protein (MTTP). A nine-month-old girl was admitted to hospital because of fever, cough, diarrhea and failure to thrive. She had low cholesterol and TG levels according to her age. The peripheral blood smear revealed acanthocytosis. Thyroid function test showed central hypothyroidism. Cranial magnetic resonance imaging revealed the retardation of myelination and pituitary gland height was 1.7 mm. A homozygous novel mutation [c.506A>T (p.D169V)] was detected in the MTTP gene. Vitamins A, D, E, and K and levothyroxine were started. The coexistence of ABL and central hypothyroidism has not previously been reported. A homozygous novel mutation [c.506A>T (p.D169V)] was detected in the MTTP gene.

Ophthalmic diagnosis and optical coherence tomography of abetalipoproteinemia, a treatable form of pediatric retinal dystrophy.

A 16-year-old boy with early-childhood-onset retinal dystrophy and developmental delay was diagnosed with abetalipoproteinemia based on ophthalmic examination, history, and results of a peripheral blood smear. The diagnosis was confirmed by lipid profile and genetic testing, and an older sister was confirmed to be affected as well. Although abetalipoproteinemia is treatable in early childhood, most cases are diagnosed late if at all. We highlight clinical features that should raise suspicion for this treatable but likely under-diagnosed form of early-onset retinal dystrophy and document retinal optical coherence tomography findings for a genetically proven case.

Update on primary hypobetalipoproteinemia.

"Primary hypobetalipoproteinemia" refers to an eclectic group of inherited lipoprotein disorders characterized by low concentrations of or absence of low-density lipoprotein cholesterol and apolipoprotein B in plasma. Abetalipoproteinemia and homozygous familial hypobetalipoproteinemia, although caused by mutations in different genes, are clinically indistinguishable. A framework for the clinical follow-up and management of these two disorders has been proposed recently, focusing on monitoring of growth in children and preventing complications by providing specialized dietary advice and fat-soluble vitamin therapeutic regimens. Other recent publications on familial combined hypolipidemia suggest that although a reduction of angiopoietin-like 3 activity may improve insulin sensitivity, complete deficiency also reduces serum cholesterol efflux capacity and increases the risk of early vascular atherosclerotic changes, despite low low-density lipoprotein cholesterol levels. Specialist laboratories offer exon-by-exon sequence analysis for the molecular diagnosis of primary hypobetalipoproteinemia. In the future, massively parallel sequencing of panels of genes involved in dyslipidemia may play a greater role in the diagnosis of these conditions.

Disease distribution in canine patients with acanthocytosis: 123 cases.

BACKGROUND: An acanthocyte is an abnormally shaped erythrocyte. In veterinary medicine, acanthocytes have historically been associated with canine hemangiosarcoma. In human medicine, acanthocytes are rarely observed with neoplastic disease and are more commonly associated with a variety of hereditary and acquired diseases. OBJECTIVES: The purpose of the study was to determine what disease processes are associated with the presence of acanthocytes in the peripheral blood of dogs. METHODS: Medical records for dogs presented to the Veterinary Teaching Hospital of Colorado State University during January 2004 through June 2008 with acanthocytes documented in their CBCs were retrospectively reviewed. RESULTS: A total of 123 dogs were included, 66 of which were diagnosed with neoplastic disease, most commonly hemangiosarcoma (n = 12), osteosarcoma (n = 11), and lymphoma (n = 11). The remaining 57 dogs had nonneoplastic disease, most commonly observed were gastrointestinal (n = 13), musculoskeletal (n = 8), renal (n = 8), and immune-mediated diseases (n = 7). No statistically significant difference was detected between percent acanthocytes present in dogs with neoplastic and nonneoplastic diseases. CONCLUSION: Acanthocytosis was observed with a variety of neoplastic and nonneoplastic diseases. While clearly commonly associated, the presence of acanthocytes in a blood smear should not be considered pathognomonic for hemangiosarcoma in dogs.

Knee pain: an unanticipated finding related to a rare genetic disorder--abetalipoproteinemia.

PURPOSE: The purpose of this case study is to raise awareness about an uncommon cause of knee pain. DATA SOURCES: Review of literature was done using PubMed, CINAHL, and Medline. There was no limitation placed on the publication year. Only articles written in English were included. CONCLUSION: Knee pain is a common diagnosis that many healthcare providers see on a daily basis in their practice. Musculoskeletal injury or trauma is most commonly identified as the cause of this symptom. However, there are rare instances in which an unexpected finding in a client's history and physical exam lead us to an unexpected cause, such as abetalipoproteinemia. Abetalipoproteinemia is a rare autosomal recessive disorder in which an affected individual does not absorb lipids or the lipid-soluble vitamins A, D, E, and K. Multiple body systems are impacted by this fat malabsorption and resultant vitamin deficiencies. Without corrective supplementation, clinical manifestations which are directly related to the vitamin deficiencies will appear as presented in this case study-knee pain. IMPLICATIONS FOR PRACTICE: This case study emphasizes the need for nurse practitioners to seek out opportunities to further our knowledge which will enhance our clinical expertise as well as the quality of the health care we provide to our clients.

A case of McLeod phenotype of neuroacanthocytosis brain MR features and literature review.

Huntington's disease and neuroacanthocytosis may present similar clinical and MRI features. It is important to differentiate these findings since treatment and prognosis vary vastly between them. The aim of this article is to familiarize radiologists with the differentiating features of Huntington's disease and various diseases comprising neuroacanthocytosis. A 40-year-old Indian man with extrapyramidal symptoms was referred for MRI. The clinical diagnosis was Huntington's disease, but there were a few atypical clinical features such as a history of biting the tongue, tics, marked hyporeflexia and lower limb muscle wasting. MR showed atrophy of the caudate nucleus and putamen with iron deposition in the basal ganglia, which can be seen in Huntington's disease and in neuroacanthocytosis. An increased blood acanthocyte level was subsequently confirmed. Further work-up revealed increased serum creatine phosphokinase levels, normal serum lipoprotein levels and depressed K cell antigen activity on serological studies, confirming the diagnosis of McLeod syndrome. McLeod syndrome is one of the distinct phenotypes of neuroacanthocytosis. Neuroacanthocytosis is a group of disorders with increased serum acanthocyte counts and neurological involvement. Various causes of neuroacanthocytosis are discussed. It is important to consider the possibility of neuroacanthocytosis when features typical of Huntington's disease are encountered on imaging.

Molecular characterization of Tunisian families with abetalipoproteinemia and identification of a novel mutation in MTTP gene.

BACKGROUND: Abetalipoproteinemia (ABL; OMIM 200100) is a rare monogenic disorder of lipid metabolism characterized by reduced plasma levels of total cholesterol (TC), low density lipoprotein-cholesterol (LDL-C) and almost complete absence of apolipoprotein B (apoB). ABL results from genetic deficiency in microsomal triglyceride transfer protein (MTP; OMIM 157147). In the present study we investigated two unrelated Tunisian patients, born from consanguineous marriages, with severe deficiency of plasma low-density lipoprotein (LDL) and apo B. METHODS: Intestinal biopsies were performed and The MTTP gene was amplified by Polymerase chain reaction then directly sequenced in patients presenting chronic diarrhea and retarded growth. RESULTS: First proband was homozygous for a novel nucleotide deletion (c. 2611delC) involving the exon 18 of MTTP gene predicted to cause a non functional protein of 898 amino acids (p.H871I fsX29). Second proband was homozygous for a nonsense mutation in exon 8 (c.923 G > A) predicted to cause a truncated protein of 307 amino acids (p.W308X), previously reported in ABL patients. CONCLUSIONS: We discovered a novel mutation in MTTP gene and we confirmed the diagnosis of abetalipoproteinemia in new Tunisian families. VIRTUAL SLIDES: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/8134027928652779.

Chronic adrenal failure and hypergonadotropic hypogonadism in a patient with abetalipoproteinemia.

INTRODUCTION: Abetalipoproteinemia is a rare inherited disorder characterized by very low plasma levels of cholesterol and triglycerides, secondary to a dramatic decrease in apolipoprotein B-containing lipoproteins, which is induced by a mutation in the microsomal triglyceride transfer protein gene. CASE: In our paper, we describe an atypical clinical manifestation of this condition in a young man, which included the presence of hypogonadism and chronic adrenal failure. We connect the development of both endocrine disorders with very low plasma levels of cholesterol, which is uptaken by the gonads and adrenal cortex and used as a substrate for steroidogenesis, accentuated by carbamazepine treatment. Testosterone treatment and administration of hydrocortisone, fludrocortisone and dehydroepiandrosterone resulted in a significant improvement in a patient's condition. CONCLUSIONS: This case shows that untreated or inaccurately managed long-lasting abetalipoproteinemia may impair the production of steroid hormones and lead to the development of some endocrine disorders.