Carnitine Free and Total


Biochemical Genetics Laboratory Carnitine, Free and Total

INDICATIONS FOR TESTING:
Carnitine analysis of serum is indicated in patients presenting with chronic muscle weakness, hypotonia, cardiomyopathy, lipid storage myopathy, SIDS, failure to thrive, hypoglycemic episodes or metabolic acidosis. Analysis of urine is indicated when a renal transport defect is suspected and after low serum values have been established.

METHODOLOGY:
Determination of free and total carnitine is performed by a radioistopic enzymatic procedure. Free carnitine is determined by incubating acetyl-CoA radiolabeled with C14, with carnitine acetyltransferase and measuring the labeled acetylcarnitine produced. Total carnitine is determined in the same manner after the sample has been hydrolyzed in an alkaline medium.

TURN-AROUND TIME:
Carnitine analysis is completed within a time of 3 working days following specimen receipt. Samples are batched.

SPECIMEN REQUIREMENTS:

  • Serum or Plasma: 1.0 mL
  • Urine: 2.0 mL

Collection Notes:

  • Urine: For initial screening a random collection is acceptable. For detailed investigations, the use of timed collections is suggested.
  • Do not use preservatives (especially strong acids).

Shipping and Handling:

  • Optimal: Ship frozen with dry ice in an insulated container
  • Acceptable: Ship thawed with cool pack in an insulated container
  • Use overnight delivery if available.

CPT CODE:

  • Carnitine: 82379

FOR MORE INFORMATION, PLEASE CONTACT:
Phone:
(727) 767-8689 (Laboratory)
Fax: (727) 767-8514
E-mail: sbenfor1@jhmi.edu