Significance of low Carnitine levels

Dear Ask The Doctor: I am a 52 year old, 5 foot 9 inches, 160 pounds, white male. I am in fair to poor health due to suffering with fibromyalgia over the past 10 years. My doctor tested my Carnitine levels last week. Total and Free Carnitine were well within the normal range, but Carnitine Esters was quite low, coming in at 1.0 on a scale of 3.8 - 19.0 umol per L. fyi...Last year, all three of these markers were low. Could this be the cause, or playing a part, in my overall fatigue and muscle tightness, pain and weakness? Thank you.

Dear Ron: Carnitine deficiency is a metabolic state in which carnitine concentrations in plasma and tissues are less than the levels required for normal function of the organism. Biologic effects of low carnitine levels may not be clinically significant until they reach less than 10-20% of normal. This may be a primary deficiency, due to a deficiency in the plasma membrane carnitine transporter, or secondary for example due to poor dietary intake or an adverse-effect of medications. If your carnitine levels have returned to normal now, but your symptoms are still present, it is unlikely your symptoms are related to carnitine deficiency.