Hemolytic anemia resident survival guide

Hemolytic anemia Resident Survival Guide
Overview
Causes
FIRE
Diagnosis
Treatment
Do's
Don'ts

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1];

Overview

• Anemia is defined as a decrease in red blood cell population in the body. Hemolytic anemia results from a premature destruction of RBCs.
• Hemolysis can be due to either extravascular or intravascular destruction of cells.
• It is caused due to a wide variety of reasons which include inherited diseases like thalassemia, sickle cell disease etc, infections, autoimmune conditions, bone marrow dysfunction, blood transfusions and certain drugs can also result in hemolytic anemia .
• Most common presenting symptoms are fatigue, palpitations, dyspnea, tachycardia and icterus in severe cases.
• Diagnosis usually requires a battery of tests including, but not limited to a peripheral smear, CBC, serum LDH, bone marrow studies, etc.
• Treatment is directed by the specific cause and can involve bone marrow transplant, splenectomy, transfusions etc.

Causes

Life threatening causes

• ABO incompatibility
• Disseminated intravascular coagulation
• Thrombotic thrombocytopenic purpura
• Hemolytic uremic syndrome
• Pre-eclampsia and malignant hypertension

Other causes

• Membrane cytoskeletal defects like hereditary spherocytosis and hereditary elliptocytosis
• Glucose 6 phosphate dehydrogenase deficiency
• Pyruvate kinase deficiency
• Sickle cell disease
• Thalassemia
• Cold agglutinin disease
• Drug induced hemolytic anemia
• Systemic lupus erythematosus
• Prosthetic heart valves
• Infectious causes such as malaria, hepatitis, CMV infection etc.

For a complete list of hemolytic anemia causes click here

Diagnosis

The approach to diagnosis of hemolytic anemia is based on a step-wise testing strategy. Below is an algorithm summarising the identification and laboratory diagnosis of hemolytic anemia.

Characterize the symptoms: ❑ Weakness ❑ Shortness of breath ❑ Jaundice ❑ Lethargy ❑ Chest pain and reduced exercise tolerance ❑ Pica

Examine the patient: ❑ Tachypnea ❑ Cold and clammy skin ❑ Hypotension ❑ HEENT signs: Conjunctival pallor Jaundice ❑ Cardiovascular exam: Tachycardia Systolic murmur ❑ Abdominal exam: Enlarged spleen RUQ pain may indicate bilirubin gallstones ❑ Skin exam: Pallor of nail beds, palmar creases Bronze skin colour in case of repeated transfusions Leg ulcers ❑ Fever and neurological signs are seen in TTP ❑ Hemoglobinuria in some cases

Initial workup for hemolysis: ❑ Indirect bilirubin ❑ serum haptoglobin ❑ Lactate dehydrogenase level ❑ Reticulocyte count ❑ Urinalysis

Peripheral blood smear

No laboratory evidence of hemolysis

Consider differential diagnosis ❑ Iron deficiency anemia ❑ Anemia of chronic disease ❑ Vitamin B12 deficiency ❑ Folate deficiency

Degmacytes

Normal cell morphology

Spherocytes

Elliptocytes

Shistocytes

Sickle shaped cells

Hypochromic, microcytic cells

G6PD deficiency

❑ Family history ❑ Drug history ❑ Recent infections

Coomb's test

Hereditary elliptocytosis

Sickle cell disease

H/o exercise, exertion, trauma or surgery?

Beta thalassemia

Negative

Positive

No

Yes

CD55/59

❑ Drug induced hemolytic anemia ❑ Autoimmune disease

❑Exercise induced hemolysis ❑Prosthetic heart valve ❑Severe aortic stenosis

Microangiopathic hemolytic anemia

Positive

Negative

Pre-eclampsia and eclampsia

Recent diarrhea

Decreased ADAMTS13 activity

Paroxysmal nocturnal hemoglobinuria

Hereditary spherocytosis

HELLP syndrome

Hemolytic uremic syndrome

Thrombotic thrombocytopenic purpura

Treatment

Do's

Don'ts

References