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Siderocyte Number Fraction, Whole Blood or Bone Marrow — Prussian Blue Stain

Published: August 9, 2026Updated: August 16, 2026

A blood or bone marrow stain that detects siderocytes, red blood cells or precursors containing visible iron deposits.

Quick summary

["This test looks for iron-containing blood cells to help evaluate iron overload and disorders of blood-cell production."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
99396-4
Short code
Siderocytes.Tp 1 NFr Bld/Mar Prus Bl St
Synonyms
Siderocytes.Tp 1 NFr Bld/Mar Prus Bl St
Category
liver
Sample
whole-blood
Container
Lavender-top (EDTA)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
prussian-blue-stain
CPT
86592
Specimen volume
3 mL
Stability
Room temperature: 4h, Refrigerated: 24h
Hemolysis max
0
Lipemia max
0
Icterus max
0
TAT
4–24 hours
Order
routine

What is this test?

This test detects siderocytes, which are red blood cells or developing red blood cells that contain iron. A laboratory uses a Prussian blue stain to make the iron deposits visible under a microscope.

Why might I need this test?

It may be ordered to investigate unexplained anemia, increased iron stores, or abnormal red blood cell production. Results are often interpreted with other tests, including a complete blood count and iron studies.

How is the test performed?

A blood or bone marrow sample is prepared on a laboratory slide and treated with the Prussian blue stain. A laboratory professional then examines the cells microscopically for blue-staining iron deposits.

How do I prepare for the test?

A blood sample generally requires no special preparation or fasting. If bone marrow is required, your clinician or laboratory will provide instructions because collection involves a medical procedure.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

An increased number of siderocytes may occur when iron accumulates in the blood-forming tissues or when the body has difficulty using iron to make hemoglobin. This can be seen with iron overload, certain inherited blood disorders, vitamin B6-related problems, medication effects, and some bone marrow disorders. The finding is not diagnostic by itself and should be interpreted with symptoms, blood counts, iron tests, and other relevant results.

Short name

Siderocyte stain

Frequently asked questions

What does a positive siderocyte result mean?
It means that iron deposits were detected in red blood cells or their precursors. This can reflect increased iron availability, impaired iron use, or another condition affecting blood-cell production.
Is bone marrow required for this test?
It depends on the test ordered and the clinical question. Some samples can be examined from peripheral blood, while bone marrow testing is commonly used when a detailed assessment of blood-cell production is needed.
Does the test show how much iron is in the body?
No. It shows whether iron-containing deposits are visible in the examined cells; it does not directly measure total body iron. Ferritin, transferrin saturation, and other iron studies may be needed for that purpose.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy