Blood Health
Prolymphocytes %
What This Marker Tells Us
Measures these most immature neutrophils as a proportion of total WBC; any percentage above 0% nearly always indicates leukemia and requires emergency evaluation.
Why It Matters
Promyelocyte percentage, like absolute count, is critically abnormal when above 0%. Promyelocytes should never appear in peripheral blood. Any percentage indicates acute leukemia (especially acute promyelocytic leukemia) or overwhelming sepsis. Even 1% promyelocytes is a medical emergency requiring immediate hematology consultation. APL (acute promyelocytic leukemia) with high promyelocyte percentage causes life-threatening bleeding through DIC, requiring emergency treatment with ATRA. Percentage form doesn't change the critical nature; any promyelocytes demand immediate action regardless of whether expressed as percentage or absolute count.
How to Interpret Your Trends
Normal promyelocytes: 0% of WBC. Any detectable percentage is critically abnormal requiring emergency evaluation. Even a single promyelocyte (below 1%) demands urgent hematologic assessment. Promyelocytes above 1-2% strongly suggest acute promyelocytic leukemia or other acute leukemias. High promyelocyte percentage (above 5-10%) with bleeding manifestations indicates APL emergency requiring immediate ATRA treatment to prevent fatal hemorrhage.
What Influences This Marker
Promyelocyte percentage increases exclusively with acute leukemias (especially APL), occasionally severe sepsis, rarely toxic exposures or G-CSF. Unlike less immature forms that might appear transiently, promyelocytes nearly always indicate malignancy requiring emergency hematologic evaluation, bone marrow biopsy, and genetic testing.
How Your Team Uses It
Your coach recognizes any promyelocyte percentage as a hematologic emergency, ensures immediate medical care, then supports treatment adherence, rest, nutrition during chemotherapy, and infection prevention during immune suppression from treatment.
Related Signals We Also Review
Absolute promyelocytes, blasts, other immature cells, platelet count, coagulation studies (APL causes DIC), peripheral blood smear, bone marrow biopsy, and emergency hematology consultation.