From the Guidelines
A high Red Cell Distribution Width (RDW) and abnormal granulocyte lab results are indicative of potential underlying health issues that require prompt medical evaluation to determine the cause and appropriate treatment, as they can be associated with conditions such as iron deficiency anemia, vitamin B12 or folate deficiency, chronic inflammatory states, infection, or other immune responses. The significance of these findings should be interpreted within the context of the patient's overall health status and symptoms. High RDW suggests variation in red blood cell size, which can occur in conditions like iron deficiency anemia, vitamin B12 or folate deficiency, or chronic inflammatory states 1. Elevated granulocytes (neutrophils, eosinophils, and basophils) typically indicate infection, inflammation, or other immune responses.
Key Considerations
- A comprehensive diagnostic workup should include a complete blood count with differential, iron studies, vitamin levels, and possibly inflammatory markers to determine the exact cause of the abnormal lab values 2.
- The minimum workup for anaemia should include red blood cell indices such as RDW and mean corpuscular volume (MCV), reticulocyte count, differential blood cell count, serum ferritin, transferrin saturation, and CRP concentration 3.
- In patients with inflammation, a serum ferritin up to 100 μg/l may still be consistent with iron deficiency, and a combination of true iron deficiency and anaemia of chronic disease is likely if the serum ferritin level is between 30 and 100 μg/l 1.
- Further laboratory tests such as B12, red cell folic acid, haptoglobin, and lactate dehydrogenase may be necessary if the cause of anaemia remains unclear 1.
Next Steps
- Consult with a healthcare provider promptly for proper assessment and diagnosis.
- Do not ignore these abnormal lab values as they could represent various conditions ranging from nutritional deficiencies to more serious disorders like myelodysplastic syndromes or certain cancers.
- A hematologist's advice may be appropriate if the cause of anaemia remains unclear after extensive workup 2.
From the Research
Significance of High Red Cell Distribution Width (RDW)
- A high RDW indicates iron deficiency anemia, hemolytic anemia, ineffective erythropoiesis, and shortened lifespan of red blood cells 4.
- Increased RDW is also prevalent in various non-anemic pathological conditions and diseases, including cardiovascular disease, acute pancreatitis, chronic kidney disease, gastrointestinal disorders, and cancer 4, 5.
- RDW reflects the degree of heterogeneous volumes of peripheral red blood cells (RBCs) and is a sensitive indicator of risk factors associated with pathological alterations and disease onset 4.
Association with Cardiovascular Disease
- High RDW is associated with worse outcomes in cardiovascular diseases, including heart failure, atherosclerotic diseases, and atrial fibrillation 6.
- RDW can be used as a valuable tool for predicting the incidence of cardiovascular diseases, including cardiomyopathies and pulmonary hypertension 6.
- The predictive role of RDW in endovascular interventions has also been demonstrated by many recent studies 6.
Diagnostic Value
- RDW can be used to distinguish iron deficiency anemia from beta-thalassaemia trait, with a RDW above 17.1 strongly suggesting the presence of iron deficiency anemia 7.
- RDW, in combination with other indicators such as hepcidin and ferritin levels, can be used to diagnose and monitor various pathological conditions, including iron and folate deficiency anemias 4, 8.
- The coefficient of variation of the red cell width (RDW-CV%) can be used to predict iron deficiency anemia and folate deficiency, with a high RDW-CV% persisting for three months after folate deficiency 8.
Abnormal Granulocyte (Gran) Lab Results
- There is no direct evidence in the provided studies to assist in answering the question about the significance of abnormal granulocyte lab results.