Inborn errors of metabolism
Inborn errors of metabolism Causes
Diet or stress (from intercurrent illness, trauma, surgery, or immunization) may result to episodic decompensation.
Inborn errors of metabolism Definition
Inborn errors of metabolism are made up of a large class of genetic diseases involving disorders of metabolism. The majority are due to defects of single genes that code for enzymes that facilitate conversion of various substances into others (products). In most of the disorders, problems occur due to accumulation of substances which are toxic or interfere with normal function, or to the effects of reduced ability to synthesize essential compounds. Inborn errors of metabolism are now often called congenital metabolic diseases or inherited metabolic diseases, and these terms are considered synonymous.
Inborn errors of metabolism Diagnosis
Common screening tests used in the last sixty years include: ferric chloride test (turned colors in reaction to various abnormal metabolites in urine); ninhydrin paper chromatography (detected abnormal amino acid patterns); guthrie bacterial inhibition assay (detected a few amino acids in excessive amounts in blood); quantitative plasma amino acids, quantitative urine amino acids; and urine organic acids by mass spectrometry.
Inborn errors of metabolism Symptoms and Signs
Abnormalities may include failure to thrive; abnormalities of hair, skin, skeleton, or all three; dysmorphic features; abnormal odor; organomegaly; and abnormal muscle tone. Clinical symptoms of IEMs tend to be nonspecific and generally relate to major organ dysfunction or failure. The same symptoms appear with sepsis, respiratory illness, cardiac disease, GI obstruction, renal disease, and CNS problems. Presence of these conditions does not eliminate the possibility of an IEM.
Inborn errors of metabolism Treatment
Some of the more common treatments of of inborn errors of metabolism include: dietary restriction; dietary supplementation; vitamins; intermediary metabolites; dialysis; enzyme replacement; gene transfer; bone marrow or organ transplant; treatment of symptoms and complications; and prenatal diagnosis.