What is anemia?

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From the Guidelines

Anemia is a condition that should be promptly diagnosed and treated to reduce the risk of morbidity and mortality, and it is defined as a hemoglobin concentration <13 g/dL in men and <12 g/dL in women, according to the World Health Organization 1.

Diagnosis and Treatment

To diagnose anemia, doctors typically order a complete blood count (CBC) to check hemoglobin levels. Treatment depends on the cause:

  • iron deficiency anemia is treated with iron supplements (typically ferrous sulfate 325mg taken 1-3 times daily between meals with vitamin C to enhance absorption) for 3-6 months
  • B12 deficiency may require injections or high-dose oral supplements
  • other types might need different approaches like erythropoietin injections or blood transfusions.

Causes and Risk Factors

It's essential to address the underlying cause, which could be:

  • blood loss (like heavy periods or gastrointestinal bleeding)
  • poor diet
  • pregnancy
  • chronic conditions
  • genetic disorders like sickle cell anemia. Some female athletes are at inherently higher risk than others for iron deficiency, including those with restrictive diets, high amounts of repetitive ground strikes, endurance training, and heavy menstrual bleeding 1.

Management and Prevention

Preoperative and intraoperative anemia management is crucial to reduce the risk of complications, and iron therapy (either oral or intravenous) administered preoperatively is reasonable to reduce blood transfusions and to increase hemoglobin 1. Anemia management programs can decrease the rate of transfusions, complications, and mortality.

  • A restrictive transfusion threshold of 8 g/dL for orthopedic surgery patients and those with CVD is recommended by the Association for the Advancement of Blood & Biotherapies 1.
  • Athletes with restrictive diets that make adequate consumption of iron difficult should consult a sports dietitian to optimize their daily nutrition plans for iron intake 1.

From the Research

Definition and Causes of Anemia

  • Anemia is a condition characterized by low hemoglobin concentration, resulting in reduced tissue oxygenation 2.
  • It can be caused by a deficiency in iron, vitamin B12, or folate, which are necessary for the production of red blood cells (erythrocytes) 2.
  • Iron-deficiency anemia is the most common cause of anemia and can produce long-term developmental outcomes 3.

Symptoms of Anemia

  • Symptoms of anemia include weakness, lethargy, palpitation, headache, and shortness of breath, resulting from reduced tissue oxygenation 2.
  • These symptoms can be masked by coexisting conditions, making diagnosis challenging 4.

Diagnosis of Anemia

  • The first-line laboratory test for suspected anemia is a full blood count, which may suggest a nutritional deficiency of B12, folate, or iron 2.
  • Laboratory measurement of iron, vitamin B12, and folate concentrations, along with other tests, can aid in differential diagnosis 2.
  • A diagnostic model based on age and homocysteine assessment can help differentiate between iron deficiency anemia and combined deficiency 4.
  • It is essential to evaluate serum vitamin B12 in iron deficiency anemia patients over 60 years old 4.

Types of Anemia

  • Microcytic anemias, including iron-deficient anemia, are the most common type of anemia 5.
  • Normocytic anemia, such as anemia of chronic disease, is a diagnosis of exclusion 5.
  • Macrocytic anemia can be differentiated based on reticulocyte count 5.

Importance of Early Detection

  • Early detection of iron depletion is crucial to prevent the development of iron deficiency anemia 6.
  • Biochemical measures, such as serum iron and ferritin, are essential for accurate diagnosis, as hemoglobin and hematocrit levels may not decrease until severe iron depletion is present 6.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Anemia: diagnosis and management.

Journal of pediatric health care : official publication of National Association of Pediatric Nurse Associates & Practitioners, 2005

Research

Anaemia: A disease or symptom.

The Netherlands journal of medicine, 2020

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.

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