Question

Anemia Case Study

A 44 year old white woman was seen in the emergency department. She complained of fatigue and weakness. Over the past 2 weeks, she had noted that the whites of her eyes and her skin were becoming yellowish looking. On physical examination, the spleen was palpable. The emergency department physician ordered a CBC, serum bilirubin and a retic count. The test findings were:

WBC: 9,000/ul

RBC: 3.0 x 10⁶/ul

Hb: 8.5 g/dl

HCT: 27%

MCV: 90.4 fl

MCHC: 32 g/dl

The reticulocyte count was 13%.

The total bilirubin was 4.2 mg/dl

The patient was admitted to the hospital. The physician ordered additional tests to include a direct and indirect AHG, and a serum haptoglobin.

DAT: 3+

IAT: 1+

Serum haptoglobin decreased

The bloodbank subsequently identified the serum antibody as a warm auto antibody that was responsible for the positive IAT as well.

Questions:

1. Which category of anemia is suggested by the laboratory findings?

2. Which specific type of anemia is present in this case?

3. What is the etiology of this anemia?

4. What mechanism produced spherocytes on the peripheral blood smear of this patient?

5. Why was the serum haptoglobin decreased?

Answer 1

1. Which category of anemia is suggested by the laboratory findings?

The lab findings suggest hemolytic anemia.

2. Which specific type of anemia is present in this case?

Warm Antibody Autoimmune hemolytic anemia is the specific type anemia in this case

3. What is the etiology of this anemia?
4. The causes for autoimmune hemolytic anemia are

• Autoimmune disorders like Lupus
• some cancers like CLL and non Hodgkin's lymphoma
• certain medicines like Quinine, Methyldopa, Penicillin and Sulfonamides.\Infections like Epstein barr virus, HIV, hepatitis, Mycoplasma pneumoniae.

4. What mechanism produced spherocytes on the peripheral blood smear of this patient?

The IgG antibodies leave the Fc portion and attach to a red blood cell. The Fc receptors of the monocytes and macrophages of spleen, recognize and grab the Fc region. These cells will pick off portions of the red cell membrane, almost as if they are taking a bite. The red blood cells losing their cell membrane, become the Spherocytes.

5. Why was the serum haptoglobin decreased?
6. Haptoglobin is generated from the liver and its one main function is to bind to the free hemoglobin released from red cell lysis. Hemolytic anemia cause more and more RBC lysis causing increased release of free hemoglobin to the circulation leading to increase number of haptoglobin binding to Hemoglobin. This inturn reduces the serum Haptoglobin levels.