Red Cell Distribution Width Standard Deviation
RDW SD
Description
"Red Cell Distribution Width – Standard Deviation" (RDW-SD) test measures the actual range of red blood cell sizes in your blood to identify potential nutrient or bone marrow issues. It’s typically ordered alongside other blood tests when symptoms like fatigue, pale skin, or shortness of breath appear. Significant variation in cell size may signal deficiencies in iron, folate, or B12. This test helps guide treatment decisions and supports accurate diagnosis of anemia-related conditions or other blood irregularities.
Category
Blood Cells
Procedure
Invasive
Sample Type
Blood – Whole Blood
Units
Femtoliters
Procedure Category
Blood Draw
Test Group
Hematology Group, Female Health Group, Male Health Group, Blood Count Basic Group
Test Group Description
Blood Count Basic Group: This group includes essential tests for evaluating blood cell counts, providing foundational information for assessing overall blood health, and detecting potential abnormalities. Female Health Group: A comprehensive array of tests provides insights into various aspects of female health and wellness, aiding in the evaluation and management of overall health for females. Male Health Group: A comprehensive array of tests provides insights into various aspects of male health and wellness, aiding in the evaluation and management of overall health for men. Hematology Group: Tests within this group focus on evaluating various aspects of blood health and function. These assessments provide insights into red blood cells, white blood cells, platelets, and other components of the blood.
Optimal Range
For All Individuals:
Conventional Unit: 39.00–46.00 fL
SI Unit: 39.00–46.00 fL
Normal Range
For All Individuals:
Conventional Unit: 38.0–51.9 fL
SI Unit: 38.0–51.9 fL
Results That Differ From The Norm (Direct and Indirect Causes)
Increased levels may indicate:
Acute blood loss
Autoimmune hemolytic anemia (Immune system attacks and destroys red blood cells)
Chronic liver disease
Hemolysis (Destruction of red blood cells)
Iron deficiency anemia (Deficiency of iron leading to decreased red blood cell production)
Megaloblastic anemia (Anemia charact...
Key Reasons For Testing
Anemia Differentiation: Helps distinguish between mixed, microcytic, and normocytic anemia.
Diagnosis of Iron Deficiency Anemia: Elevated RDW-SD supports identification of iron deficiency anemia when combined with other parameters.
Monitoring Response to Treatment: Tracks changes in RDW-SD to assess the effectiveness of treatment for anemia or related conditions.
Hematological Disorder Screening: Identifies conditions like thalassemia or sickle cell disease for diagnosis and management.
Health Status Conditions It May Be Used To Assess
Currently, this test is not directly associated with any conditions listed on the Health Status page. However, it may be included as part of a broader set of tests linked to specific health conditions.
Some Prominent Medical Labs That May Offer This Test
Please note that this particular test has not been associated with any of the listed prominent medical labs. We recommend enquiring with your private physician or nearest hospital to determine where this specific test can be performed.
References
Important Note
Any medical procedure yielding results outside the norm may be directly or indirectly linked to the conditions outlined on this page. Various factors, including genetics, medication and supplement usage, recent illnesses, pregnancy, pre-test eating, smoking, and stress, can impact the test's outcome. Additionally, factors like false positives, false negatives, inaccurate analyses, and others can influence results.
Reference ranges, which help healthcare professionals interpret medical tests, may vary depending on age, gender, and other factors. They may also differ between laboratories due to variations in instruments and methods used. Optimal ranges are designed for preventive purposes, aiming to identify trends and potential risks early, while normal ranges reflect conventional laboratory values indicating no current disease or pathology. Your healthcare practitioner may have specific reasons for testing that deviate from the usual or may interpret results differently based on individual circumstances. Proper interpretation typically involves considering clinical findings and other diagnostic tests. Hence, it is crucial to provide your healthcare professionals with a comprehensive medical history, consult with them for result interpretation, and follow their guidance for potential re-testing or additional diagnostics.
Disclaimer
This content is provided solely for informative and educational purposes. It is not intended as a substitute for medical advice or treatment from a personal physician. Regarding the interpretation of their medical test results and/or specific health questions, it is recommended that all readers and viewers consult their physicians or other qualified health professionals. The publisher is not responsible for any adverse health effects that may result from reading or following the information in this educational content. Before beginning any nutrition, supplement, or lifestyle program, all viewers, especially those taking prescription or over-the-counter medications, should consult their physician or health care practitioner.
Please note that while prominent lab names are included in this content, we cannot guarantee that these labs offer all the tests mentioned. For confirmation, individuals should contact the labs directly or consult their medical practitioners. The information provided reflects general knowledge at the time of publication and may not include recent updates or emerging research. Readers should verify details with qualified professionals to ensure the most up-to-date and accurate guidance.
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