Hereditary disorders of amino acid metabolism / Questions and case reports

Questions

 * 1) Which amino acids are mainly taken up by the kidneys?
 * 2) * A – glycine
 * 3) * B – arginine
 * 4) * C – alanine
 * 5) * D – glutamic acid
 * 6) * E – glutamine
 * 7) * F – leucine
 * 8) * G – histidine
 * 9) * H – tyrosine
 * 10) Which amino acids does the muscle supply to the bloodstream in the largest amount?
 * 11) * A – glycine
 * 12) * B – arginine
 * 13) * C – alanine
 * 14) * D – Glutamic acid
 * 15) * E – glutamine
 * 16) * F – leucine
 * 17) * G – histidine
 * 18) * H – tyrosine
 * 19) Enzyme defects in the urea cycle lead to brain disorders. What is the cause?
 * 20) * A – Hyperammonemia
 * 21) * B – Formation of atypical amino acids
 * 22) * C – Increased formation of biogenic amines
 * 23) * D – Hyperuricemia
 * 24) * E – Hypoglycemia (glukoneogenesis from amino acids is reduced)
 * 25) Which amino acids are not nutritionally essential??
 * 26) * A – Methionine
 * 27) * B – Phenylalanine
 * 28) * C – Cysteine
 * 29) * D – Tyrosine
 * 30) * E – Leucine
 * 31) * F – Isoleucine
 * 32) * G – Valin
 * 33) * H – Threonine
 * 34) Which amino acids are not glucogenic?
 * 35) * A – Isoleucine
 * 36) * B – Leucine
 * 37) * C – Histidine
 * 38) * D – Cystine
 * 39) * E – Lysine
 * 40) * F – Valin
 * 41) * G – Tryptophan
 * 42) Tyrosine is a precursor for the synthesis of:
 * 43) * A – Noradrenaline
 * 44) * B – Adrenaline
 * 45) * C – Melanin
 * 46) * D – DOPA
 * 47) The key intermediate metabolites for cysteine ​​synthesis in the liver are:
 * 48) * A – Argininosuccinate
 * 49) * B – Homoserine
 * 50) * C – Glutamic acid semialdehyde
 * 51) * D – Cystathionine
 * 52) * E – Xanthurenic acid
 * 53) The mechanism of renal creatinine exrecion is:
 * 54) * A – In glomerular filtration (without tubular secretion or tubular reverse resorption)
 * 55) * B – In glomerular filtration and in a small proportion of tubular secretion
 * 56) * C – In glomerular filtration and tubular reverse resorption
 * 57) * D – In tubular secretion
 * 58) In prerenal uremia, it is
 * 59) * A – Increased creatinine in proportion to increased urea
 * 60) * B – Increased urea and creatinine at the upper limit of normal
 * 61) * C – Increased creatinine and urea at the upper limit of normal
 * 62) * D – Creatinine and urea only at the upper limit of normal..

Infant with psychomotor retardation
Infant, 3 and 1/2 months, normal birth. After a few weeks, the mother observed that the child (compared to siblings) showed little interest in the surroundings and that it was not doing well. The urine in the diapers had a strange smell, like a mouse. The girl also had tremors in her limbs. Guthrie's positive test for hyperphenylalaninemia was demonstrated in the laboratory, urine reacted positively with ferrochloride to phenylpyruvic acid. Plasma phenylalanine concentration: 1089 olmol / l (N:  109 mol / l). Examination of the liver biopsy showed a significant reduction (to 1%) in phenylalanine hydroxylase. This suggests the presence of a "classical" form of phenylketonuria

Questions:
 * 1) Why can't the presence of phenylalanine in the diet be completely ruled out in the dietary treatment of phenylketonuria?
 * 2) What might be the risk of a fetus of a pregnant woman with phenylketonuria (who did not inherit this disorder)?
 * 3) Can the body of a patient with phenylalanine hydroxylase deficiency produce tyrosine?

Patient with ocular lens dislocation and mild retardation with a seizure
The boy, 15 years old, suddenly had a seizure resembling a "grand-mal". The doctor found muscle weakness in his left cheek and left upper and lower limbs, so he sent the boy to hospital with a diagnosis of a cerebrovascular accident (right hemisphere). Here he underwent a more detailed examination and a history of surgery (iridectomy) of both eye lenses due to their large dislocation. The boy was slightly mentally retarded. These data led to a more detailed examination of sulfur-containing amino acids. The findings confirmed the diagnosis of homocystinuria: total serum homocystest (s) in - 965 μmol / l (N: <30), cysteine ​​not measurable, folate and B12 normal.

Questions:
 * 1) Which enzyme is deficient in this disease and what changes does it lead to in amino acid metabolism?
 * 2) Can increased levels of homocyst (s) and homocystinuria also be caused by diet?
 * 3) Elevated homocysteine ​​levels are a risk factor. For which conditions?

Patient with renal colic
The boy, 16 years old, was hospitalized for severe pain in his left hip shooting into the pubic area. He had reddish-brown urine and marked erythrocyturia in the urine, and flat acidic hexagonal crystals were found in the sediment after acidification of the urine with acetic acid. Imaging techniques found stones in both kidneys.

Questions:
 * 1) What urinary calculus is possible here?
 * 2) What disorder is the essence of hereditary cystinuria?
 * 3) How can the formation of cystine stones be prevented or at least reduced?
 * 4) What is the difference between cystinuria and cystinosis?

Related articles
Other chapters from the book
 * Hereditary disorders of aino acid metabolism
 * Disorders of ureagenesis