What are myelocytes (immature granulocytes)?

Medical Advisory BoardAll articles are reviewed for accuracy by our Medical Advisory Board
Educational purpose only • Exercise caution as content is pending human review
Article Review Status
Submitted
Under Review
Approved

Last updated: May 1, 2025View editorial policy

Personalize

Help us tailor your experience

Which best describes you? Your choice helps us use language that's most understandable for you.

From the Research

Myelocytes are immature white blood cells that are normally found in bone marrow and their presence in peripheral blood typically indicates a pathological condition. When considering the morbidity, mortality, and quality of life outcomes, it is crucial to identify the underlying cause of myelocytes in peripheral blood. The presence of myelocytes in blood is called a "left shift" because it represents a shift toward immature cells in the maturation sequence. Normal myelocyte development occurs in the bone marrow where they undergo division and maturation before being released as fully functional granulocytes. Myelocytes contain specific granules in their cytoplasm and have round to oval nuclei, distinguishing them from more mature forms. Laboratory identification of myelocytes in peripheral blood requires microscopic examination of a blood smear by trained professionals, and their presence should prompt further investigation to determine the underlying cause, as suggested by 1. Some of the possible causes of myelocytes in peripheral blood include leukemia, myeloproliferative disorders, severe infections, or bone marrow infiltration by cancer, as discussed in 2, 3, and 4. However, the diagnosis of mycobacterial and fungal infections in patients with acquired immunodeficiency syndrome using bone marrow core biopsy specimens has limited value, as shown in 5. In terms of diagnosis, a thorough review of the patient's clinical record, a thorough morphologic review of the bone marrow with appropriate ancillary stains, and an appreciation of the causes of bone marrow necrosis in different patient populations are required to determine the underlying cause of myelocytes in peripheral blood, as recommended by 1. Key points to consider when evaluating myelocytes in peripheral blood include:

  • The clinical significance of myelocytes in peripheral blood
  • The possible causes of myelocytes in peripheral blood, such as leukemia, myeloproliferative disorders, severe infections, or bone marrow infiltration by cancer
  • The importance of laboratory identification of myelocytes in peripheral blood using microscopic examination of a blood smear by trained professionals
  • The need for further investigation to determine the underlying cause of myelocytes in peripheral blood. Given the potential severity of the underlying causes, prompt and thorough investigation is essential to determine the cause of myelocytes in peripheral blood and to guide appropriate treatment, as emphasized by the most recent study 4.

Related Questions

What is the most likely diagnostic test to confirm the diagnosis in a 6-year-old boy with Down syndrome, presenting with fever, generalized weakness, fatigue, diffuse limb pain, and enlarged cervical lymph nodes, with a history of congenital atrial septal defect (atrial septal defect) repair?
What is the appropriate management for a patient with abnormal CBC results suggesting a bone marrow response to stress or infection?
How do you diagnose leukemia in a patient with leukocytosis (elevated white blood cell count) and a white blood cell count of 35,000 cells per microliter (hyperleukocytosis)?
What is the significance of myelocytes in a Complete Blood Count (CBC)?
How to proceed with a 2-year-old presenting with thrombocytosis, anemia, and tear drop cells on peripheral smear?
What is the treatment for a hypertensive emergency with signs of heart failure and acute kidney injury (AKI)?
What is the risk of fetal injury with manual vaginal replacement and elevation of an impacted fetal head?
What are the indications for intramuscular (IM) and oral (po) corticosteroids for seasonal allergic rhinitis?
What is the significance of elevated Blood Urea Nitrogen (BUN) and creatinine levels, indicating Impaired Renal Function, with an estimated Glomerular Filtration Rate (eGFR) of 44, calculated using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) formula?
What potassium disorder is commonly associated with post-renal acute kidney injury (AKI)?
What is the effect of Atenolol (Beta blocker)?

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

Have a follow-up question?

Our Medical A.I. is used by practicing medical doctors at top research institutions around the world. Ask any follow up question and get world-class guideline-backed answers instantly.