Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0024523 (malabsorption)
 7,319 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Acanthocytes have a distinct morphology and are not normally found in peripheral blood. They occur in association with at least three neurological syndromes. In abetalipoproteinaemia, a progressive spinocerebellar ataxia and retinopathy occurs secondary to malabsorption of vitamin E. Cases with chorea are often familial, with orofacial dyskinesia and an axonal neuropathy causing areflexia and muscle wasting. Areflexia and a subclinical myopathy also occur in the McLeod syndrome, in which there is abnormal expression of Kell blood group antigens. The exact mechanism of acanthocytosis in each disorder remains uncertain: passive changes in membrane lipids, surface receptor/ligand interactions, and a primary membrane defect are among the possibilities.
 ...
PMID:Acanthocytosis and neurological impairment--a review. 268 30

Neuroacanthocytosis is an inclusive term for a genetically heterogeneous group of disorders characterized by the association of neurological abnormalities with red cell acanthocytosis. In the late 1960s, Levine et al. reported a family with a syndrome of neurological deficits such as choreiform involuntary movements, epileptic seizures, intellectual impairment, and paranoid ideation along with acanthocytosis without any disturbance in either alpha- or beta-lipoproteins nor retinitis pigmentosa. Critchley et al. also reported familial cases with acanthocytosis and neurological disorders without beta-lipoproteinemia. These cases have been classified as the Levine-Critchley syndrome of neuroacanthocytosis. Cases of neuroacanthocytosis have been classified into 2 groups depending on the presence or absence of movement disorders such as chorea. One group comprises the core neuroacanthocytosis syndromes in which neurodegeneration occurs primarily in the basal ganglia, specifically the striatum, causing movement disorders. The core neuroacanthocytosis syndromes mainly comprise of the two diseases, chorea-acanthocytosis and the McLeod syndrome. Huntington's disease-like 2, and pantothenate kinase-associated neurodegeneration (PKAN) are very rare but these diseases can also be included in this group of syndromes. Advances in molecular genetics have enabled us to distinguish between these diseases. Recently, the hypoprebetalipoproteinemia, acanthocytosis, retinitis pigmentosa and pallidal degeneration syndrome (HARP syndrome) has been genetically shown to be an allelic form of PKAN. The second group of neuroacanthocytosis syndromes includes abetalipoproteinemia (Bassen-Kornzweig disease) and hypobetalipoproteinemia that are characterized by the abnormal decay of lipoprotein with the intestinal malabsorption of fat leading to neurological abnormalities and acanthocytosis. In this type of neuroacanthocytosis shows a progressive spinocerebellar ataxia with peripheral neuropathy and retinitis pigmentosa are observed, but movement disorders are not seen.
 ...
PMID:[Neuroacanthocytosis update]. 1856 59

Neuroacanthocytosis (NA) syndromes are a group of genetically defined diseases characterized by the association of red blood cell acanthocytosis and progressive degeneration of the basal ganglia. NA syndromes are exceptionally rare with an estimated prevalence of less than 1 to 5 per 1'000'000 inhabitants for each disorder. The core NA syndromes include autosomal recessive chorea-acanthocytosis and X-linked McLeod syndrome which have a Huntington's disease-like phenotype consisting of a choreatic movement disorder, psychiatric manifestations and cognitive decline, and additional multi-system features including myopathy and axonal neuropathy. In addition, cardiomyopathy may occur in McLeod syndrome. Acanthocytes are also found in a proportion of patients with autosomal dominant Huntington's disease-like 2, autosomal recessive pantothenate kinase-associated neurodegeneration and several inherited disorders of lipoprotein metabolism, namely abetalipoproteinemia (Bassen-Kornzweig syndrome) and hypobetalipoproteinemia leading to vitamin E malabsorption. The latter disorders are characterized by a peripheral neuropathy and sensory ataxia due to dorsal column degeneration, but movement disorders and cognitive impairment are not present. NA syndromes are caused by disease-specific genetic mutations. The mechanism by which these mutations cause neurodegeneration is not known. The association of the acanthocytic membrane abnormality with selective degeneration of the basal ganglia, however, suggests a common pathogenetic pathway. Laboratory tests include blood smears to detect acanthocytosis and determination of serum creatine kinase. Cerebral magnetic resonance imaging may demonstrate striatal atrophy. Kell and Kx blood group antigens are reduced or absent in McLeod syndrome. Western blot for chorein demonstrates absence of this protein in red blood cells of chorea-acanthocytosis patients. Specific genetic testing is possible in all NA syndromes. Differential diagnoses include Huntington disease and other causes of progressive hyperkinetic movement disorders. There are no curative therapies for NA syndromes. Regular cardiologic studies and avoidance of transfusion complications are mandatory in McLeod syndrome. The hyperkinetic movement disorder may be treated as in Huntington disease. Other symptoms including psychiatric manifestations should be managed in a symptom-oriented manner. NA syndromes have a relentlessly progressive course usually over two to three decades.
 ...
PMID:Neuroacanthocytosis syndromes. 2202 13