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Test ID PFK1 Phosphofructokinase Enzyme Activity, Blood

Specimen Required

Collection Container/Tube:

Preferred: Yellow top (ACD solution B)

Acceptable: Lavender top (EDTA)

Specimen Volume: 6 mL

Collection Instructions: Send specimen in original tube. Do not transfer blood to other containers.

Useful For

Evaluation of individuals with Coombs-negative nonspherocytic hemolytic anemia


Evaluation of individuals with exercise intolerance or myopathy


Genetic studies in families with phosphofructokinase deficiency

Method Name

Kinetic Spectrophotometry

Reporting Name

Phosphofructokinase, B

Specimen Type

Whole Blood ACD-B

Specimen Minimum Volume

1 mL

Specimen Stability Information

Specimen Type Temperature Time Special Container
Whole Blood ACD-B Refrigerated 11 days

Clinical Information

Phosphofructokinase (PFK) is the third enzyme in glycolysis. It converts fructose-6-phosphate to fructose 1,6-diphosphate. PFK deficiency, also called glycogen storage disease, type VII or Tarui disease (OMIM 232800), is a rare hereditary autosomal recessive disorder that is typically noticed in childhood. Different clinical subtypes (classical, late-onset, infantile and hemolytic) have been described. Manifestations can vary including exercise intolerance, exertional myopathy, nausea, stiffness, and myoglobinuria. Although not classically described, a second-wind effect is noticed by some patients (1). A subset of individuals have compensated (high normal hemoglobin values) or mild hemolytic anemia, episodic jaundice, hyperuricemia, or gout-like symptoms. No distinctive morphologic abnormalities are seen on the peripheral blood smear. Red blood cell PFK activity is typically partially decreased (30-50% mean normal) and muscle biopsy PFK activity is markedly decreased.

Reference Values

≥12 months of age: 5.8-10.9 U/g Hb

Reference values have not been established for patients who are <12 months of age.


Clinically significant disorders due to phosphofructokinase (PFK) deficiency are associated with red blood cell activity levels less than 50% of mean normal. Unaffected heterozygotes have been reported with levels of 63% of normal. Therefore genetic correlation will often be important in ambiguous cases.

Clinical Reference

1. Sherman JB, Raben N, Nicastri C, et al: Common mutations in the phosphofructokinase-M gene in Ashkenazi Jewish patients with glycogenesis VII--and their population frequency. Am J Hum Genet. 1994 Aug;55(2):305-313

2. Tarui S, Okuno G, Ikura Y, Tanaka T, Suda M, Nishikawa M: Phosphofructokinase deficiency in a skeletal muscle. A new type of glycogenosis. Biochem Biophys Res Commun. 1965 May 3;19:517-23. doi: 10.1016/0006-291x(65)90156-7

3. Musumeci O, Bruno C, Mongini T, et al: Clinical features and new molecular findings in muscle phosphofructokinase deficiency (GSD type VII). Neuromuscul Disord. 2012 Apr;22(4):325-330

4. Nakajima H, Raben N, Hamaguchi T, Yamasaki T: Phosphofructokinase deficiency; past, present and future. Curr Mol Med. 2002 Mar;2(2):197-212. doi: 10.2174/1566524024605734

5. Auranen M, Palmio J, Ylikallio E, et al: PFKM gene defect and glycogen storage disease GSDVII with misleading enzyme histochemistry. Neurol Genet. 2015 Jun 4;1(1). doi: 10.1212/NXG.0000000000000007

6. Raben N, Sherman JB: Mutations in muscle phosphofructokinase gene. Hum Mutat. 1995;6(1):1-6. doi: 10.1002/humu.1380060102

7. Koralkova P, van Solinge WW, van Wijk R: Rare hereditary red blood cell enzymopathies associated with hemolytic anemia-pathophysiology, clinical aspects and laboratory diagnosis. Int J Lab Hematol. 2014; 36: 388-397. doi: 10.1111/ijlh.12223

CPT Code Information


LOINC Code Information

Test ID Test Order Name Order LOINC Value
PFK1 Phosphofructokinase, B 72664-6


Result ID Test Result Name Result LOINC Value
PFKCL Phosphofructokinase, B 72664-6

Test Classification

This test was developed, and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the US Food and Drug Administration.

Day(s) Performed

Tuesday, Thursday

Report Available

1 to 6 days