Amino Acid profile in Urine

[JanB]

I was reviewing my medical records, preparing to see a physician at the Cleveland Clinic next week.  I have been diagnosed here in MS as having "mitochondrial Myopathy"....with symptoms of slight reflux and muscle weakness (widespread) and type II muscle atrophy, most notibly in small muscles of ankles and wrists.  I get tired walking up steps, etc.  The test I am questioning is an amino acid profile...both the laboratory pathologist and my neuro at the University checked it as being a normal amino acid profile, but almost all the amino acids fall well below the minimum to maximum range.  An example is :
        Mine           Min       Max
Taurine   36           220        510
Phosphoethanol  11       20       1800
Aspartate   4            60        240
In the 40 amino acids tested, only 14 were somewhat in normal range (usually very low normal), and others were really low or 0.  Is this clearly a misreading of the test, or is there something I am missing in quantitative urine amino acids 101.  Thank you....JanB

[MedAmic]

A related discussion, Amino Acids was started.

[Jan Bailey]

I forgot to ask if taking some of these amino acids as supplements would help my body make healthier cells or would I just be making very expensive urine.  Red ragged fiber was found in my biopsy and abnormal EMG at the junctures and stress test/pulmonary function helped confirm my diagnosis.

[CCF Neuro[P] MD, RPS]

Dear Jan B:

The amino acid values obtained in the urine are variable and there is a large range found in "normal" values".  However, this can be somewhat changed by minor changes in when the urine was collected (the first morning void when the amino acids have had a chance to accumulate-for instance).  They can also be changed by diet, and individual amino acid uptake mechanisms in the kidney (also kidney function).  Unless the values are extremely outside the range of normal, or are in a particular pattern, we usually do not call abnormal amino acids values in the urine.  For instance, if you had maple syrup urine disease a certain profile of amino acids would be altered.  Most of the time in mitochondrial disease investigation, we are looking for gross increases of amino acids in the urine testing for proximal renal tubular acidosis.  Also, ruling out other diseases, such as the above mentioned maple syrup urine disease.  I would not place too much emphasis on the urine amino acids.  Much more important are the other lab values such as lactate, pyruvate, serum amino acids, urine organic acids, and then if needed the muscle biopsy with electron transport and oxidative phosphorylation determination and electron microscopy of the muscle.  

I hope that your disease will be identified.

Sincerely,

CCF Neuro MD