85557 Rbc osmotic fragility
Also known as: Incubated osmotic fragility, heated osmotic fragility
Incubated osmotic fragility test measures red blood cell resistance to hypotonic solution after 24-hour incubation, increasing sensitivity for detecting mild hereditary spherocytosis and other membrane defects.
In Plain Language
Stress-tested red blood cell test; Aged cell fragility assessment
Clinical Context
More sensitive than unincubated test for early or mild hereditary spherocytosis and other chronic hemolytic anemias. Used when baseline test is borderline.
RVU Information
CPT 85557 does not have a physician work RVU assigned by CMS. Reimbursement for this code is determined by payer-specific fee schedules.
Billing & Documentation
Lab and pathology codes require an order from the treating provider with clinical indication. For molecular pathology and genetic testing, document the specific analytes tested and clinical rationale.
How This Code Compares
This code has a work RVU of 0.00, meaning it does not have a physician work component assigned by CMS. In the Pathology & Lab category, 94% of codes share this characteristic.
Specialties
Frequently Asked Questions
What is CPT code 85557?
CPT 85557 (Rbc osmotic fragility) is a Pathology & Lab code. Incubated osmotic fragility test measures red blood cell resistance to hypotonic solution after 24-hour incubation, increasing sensitivity for detecting mild hereditary spherocytosis and other membrane defects.
Who uses CPT code 85557?
CPT 85557 is used by Hematology, Clinical Pathology, Transfusion Medicine. More sensitive than unincubated test for early or mild hereditary spherocytosis and other chronic hemolytic anemias. Used when baseline test is borderline.
When is CPT 85557 used?
More sensitive than unincubated test for early or mild hereditary spherocytosis and other chronic hemolytic anemias. Used when baseline test is borderline.
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CPT® is a registered trademark of the American Medical Association. Data sourced from CMS Physician Fee Schedule RVU26A. Descriptions, synonyms, and clinical context are original content by RVU Edge.