Lab Dept:


Test Name:

PNH Testing

General Information

Lab Order Codes:



Paroxysmal Nocturnal Hemoglobinuria; CD59; Pi-linked Antigen; Acid Hemolysin; FLAER; Ham-Crosby Sugar-Water Test; Sucrose Fragility

CPT Codes:

88184 – Flow cytometry; 1st marker, red blood cell 88184 – Flow cytometry; 1st marker, white blood cell
88185 x6 – Flow cytometry; each additional marker, WBC
88185 – Flow cytometry; each additional marker, RBC

Test Includes:

Flow cytometry evaluation of PI-Linked antigens and when positive will include a pathologist review and interpretation when appropriate.


Test Indications:

The assay is useful in screening or in confirming the diagnosis of PNH and in following those patients. It will detect the presence or absence of GPI-linked antigens on the surface of peripheral blood granulocytes, monocytes, erythrocytes, and/or lymphocytes. The sugar water test and the Ham’s test are not suggested for the evaluation of patients with possible PNH.

Lab Testing Sections:

Hematology - Sendouts

Referred to:

Mayo Medical Laboratories (MML Test: PLINK)

Phone Numbers:

MIN Lab: 612-813-6280

STP Lab: 651-220-6550

Test Availability:

Daily, 24 hours

Turnaround Time:

1 – 2 days, testing set up daily

Special Instructions:

Obtain special collection tube from the laboratory. See Container


Specimen Type:

Whole blood


Yellow top (ACD solution B) tube, preferred
Alternate tube: Lavender top (EDTA) tube

Draw Volume:

2.6 mL (Minimum: 1 mL) blood OR 7 mL in ACD or Lavender (EDTA tube)

Processed Volume:

Same as Draw Volume.


Routine venipuncture. Mix thoroughly by gentle inversion.


Special Processing:

Lab Staff: Do not centrifuge. Specimen should remain in original collection container. Store and ship at ambient temperature. Must arrive within 72 hours of collection. Specimen must not be frozen.

Patient Preparation:


Sample Rejection:

Improper specimen collection or handling; clotted specimen; frozen specimen; mislabeled or unlabeled specimens



RBC Partial Antigen Loss
(RBC Type II)

0.00 – 0.99%

RBC Complete Antigen Loss
(RBC Type III)

0.00 – 0.01%


0.00 –  0.01%


0.00 – 0.05%

An interpretive report will be provided


The sugar water test and Ham’s test are no longer recommended for the evaluation of patients with possible PNH.


Flow Cytometric Immunophenotyping


Mayo Medical Laboratories Web Page August 2015


3/11/04: Test moved from Allina-United Hospital Flow Cytometry Laboratory to Mayo Medical Laboratories.
4/25/2005: Updated for 2005 CPT coding. Previously listed as 88184 x4.
3/16/2010: Test updated at MML to include additional antibodies, change in CPT coding. Change in ref ranges and reporting.
4/22/2013: RBC Type I no longer reported. Updated names for RBC Types II and III.