Ordering Recommendation

Preferred test for initial diagnosis of paroxysmal nocturnal hemoglobinuria (PNH) and quantification of PNH clones.




Quantitative Flow Cytometry




1-3 days

New York DOH Approval Status

This test is New York DOH approved.

Specimen Required

Patient Preparation

Lavender (EDTA), pink (K2EDTA), or green (sodium or lithium heparin).

Specimen Preparation

Transport 4 mL whole blood. (Min: 4 mL)

Storage/Transport Temperature


Unacceptable Conditions

Bone marrow. Clotted or hemolyzed specimens.


Specimens must be analyzed within stability times provided.


Ambient: 24 hours; Refrigerated: 72 hours; Frozen: Unacceptable
New York State Clients: Ambient: 24 hours; Refrigerated: 48 hours. Frozen: Unacceptable

Reference Interval

By report

Interpretive Data

This test is preferred for the initial diagnosis of PNH, and was developed according to published guidelines (Cytometry B Clin. Cytom. 2010; 78:211) and as updated in 2014 (Cytometry B Clin. Cytom. 2014; 86:44). The test includes high-sensitivity WBC and RBC analysis with lower limits of detection of 0.005 percent for RBCs, 0.005 percent for PMNs, and 0.020 percent for monocytes.

WBC analysis is the most accurate measurement of the PNH clone size. FLAER and CD157 are used as GPI-linked markers; CD15 (PMNs) and CD64 (monocytes) are used as lineage-specific markers. RBC analysis quantifies Type II and Type III RBC clones when the percentage of PNH RBCs is greater than 1 percent. Glycophorin A (CD235a) is used to gate the RBC population, and CD59 is the GPI-linked antigen. Recent RBC transfusions may decrease the percentage of PNH cells measured in RBCs (Cytometry 2000; 42:223). The presence of a subclinical PNH population in myelodysplastic bone marrow disorders, such as aplastic anemia or refractory anemia, may correlate with a positive immunotherapeutic response (Blood 2006; 107, 1308-1314).

Compliance Category

Laboratory Developed Test (LDT)


Hotline History


CPT Codes

86356 x7


Component Test Code* Component Chart Name LOINC
2004367 % PNH RBC 33662-8
2005004 % PNH Monocytes 60554-3
2005005 % PNH PMN 53831-4
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.


  • CD15, CD33, CD14, CD24, FLAER, CD59, Glycophorin A
  • PI-Linked Antigens, RBCs, Monocytes and Granulocytes
Paroxysmal Nocturnal Hemoglobinuria (PNH), High Sensitivity, RBC and WBC