Primary Care for COMLEX Level 1. Dr. Jahan Eftekar

      Defective Enzymes and their Associated Key Concepts

      Adenosine Deaminase Deficiency

      •SCID (Severe Combined Immuno-Deficiency)

      •AKA: Swiss-type agammaglobulinemia

      •Humoral and cell-mediated defects.

      •T and B cell deficiency.

      •Autosomal recessive

      Arylsulfatase A Deficiency

      •Metachromatic leukodystrophy

      •Sphingolipidoses

      •Deficient enzyme activity in leukocytes

      •Demyelinating disease

      •Autosomal recessive

      Carbamoyl Phosphate Synthase Deficiency

      •Hyperammonemia, metabolic alkalosis and mental retardation

      •Ceramidase Deficiency

      •Farber’s Disease

      •Ceramide is not converted to sphingosine

      •Ceramide accumulation

      •Deformed joints; fatal

      •Autosomal recessive

      Carnitine-acyl Transferase Deficiency

      •Genetic inability to use long chain fatty acids as a source of energy by muscle

      •Muscle cramp and fatigability

      •Rhabdomyolysis

      Cystathionine Synthase Deficiency

      •Homocystinuria

      •Body deprived of pyridoxine (vitamin B₆)

      •Increased blood methionine

      Citrate Synthase Deficiency

      •Kreb’s malfunction

      •Lack of ATP production.

      α1-4, 1-6 Glucosidase Deficiency

      •Branching enzyme

      •Anderson’s disease

      •Glycogen Storage Disease Type IV

      •Cirrhosis; Accumulation of long-outer branch glycogen in the liver and spleen.

      •Fatal

      •Autosomal recessive

      α-1,6-Glucosidase Deficiency

      •De-branching enzyme

      •Cori’s Disease

      •Glycogen Storage Disease Type III

      •Glycogen accumulation in liver, heart and skeletal muscles

      •Mild hypoglycemia, little or no cardiomegaly.

      Enolase Deficiency

      •Hemolytic Anemia

      •Glycolytic anomaly

      •Not commonly tested on the exam

      Fructose-1-P Aldolase Deficiency

      •AKA: Aldolase B

      •Fructose Poisoning

      •Accumulation of fructose 1-P

      •Hypoglycemia; hepatic and renal damage

      •Fructosemia and fructosuria

      •Autosomal recessive

      Fructokinase Deficiency

      •Essential Fructosuria

      •Fructose accumulation.

      •Benign

      •Autosomal recessive

      Fructose-1, 6-Diphosphatase Deficiency

      •Lactic Acidosis

      •Failure of gluconeogenesis and hypoglycemia

      Galactosamine Sulfate Sulfatase Deficiency

      •Morquio’s Syndrome

      •Mucopolysaccharidoses

      •Increased keratan sulfate

      •Severe nervous system anomaly

      •Autosomal recessive

      α-Galactosidase Deficiency

      •Fabry’s Disease

      •Ceramide accumulation

      •Neuropathy, vascular thromboses, and renal failure (nephritic sysndrome)

      •The most benign lipid storage disease

      •X-linked

      Galactosyl Uridyl Transferase Deficiency

      •Classic Galactosemia

      •Galactose 1-P accumulation, mental retardation, hepatomegaly, jaundice and mental retardation

      •Autosomal recessive

      β-Gangliosides A Deficiency

      •GM1-Gangliosidosis (Sphingolipidoses)

      •GM1 to GM2 transformation is affected

      •Autosomal recessive

      Glucocerebrosidase Deficiency

      •Gaucher’s Disease

      •Glucocerebroside accumulation in brain, spleen and bone marrow

      •Hepatosplenomegaly