LE cell phenomenon

What sample is needed for the LE cell phenomenon?

• 5 to 10 mL of venous blood from the patient is taken and traumatized with a glass rod or glass beads.

What are the Indications for the LE cell phenomenon?

• This is done to diagnose Systemic lupus erythematosus.  (SLE).

What are the signs and symptoms of Systemic lupus erythematosus?

1. Systemic symptoms like fever, malaise, and inflammation of serous membranes like the pericardium.
2. Facial skin rash.
3. Arthritis.
4. Renal diseases like nephritis.
5. SLE is more common in females, predominantly young or middle-aged adults.
   1. In one study, the mean age was 30 (the majority between 14 and 40 years).
   2. Fewer patients were seen between the ages of 40 and 55 years.
   3. Few cases were seen in infancy to 14 years and over 55 years.
6. Hepatomegaly was seen in 30% of the cases.
7. Splenomegaly was seen in 20% of the cases.
8. Lymphadenopathy was seen in 50% of the cases.

What are the Lab findings of SLE?

1. Anemia is present in 60% to 75% of the cases.
   1. Anemia is mild to moderate, normocytic, and normochromic.
   2. <10% develop autoimmune hemolytic anemia.
2. Leucopenia is seen in 50% of the patients.
3. 15% may develop thrombocytopenia.
4. 30% of the patients have positive direct Coombs test.
5. There may be abnormal plasma proteins like:
   1. Cold-precipitable cryoglobulins.
   2. Circulating anticoagulants.
   3. Autoantibodies.
   4. Circulating immune complexes.
   5. Raised gamma-globulins.
   6. Syphilis serologic reactions.
   7. False positive RA factor.
   8. Some rare phenomena.
6. In active nephritis, C3 and C4 are decreased.

What type of autoantibodies are seen in SLE?

How will you discuss the pathophysiology of the LE cell phenomenon?

1. Systemic lupus erythematosus is a typical autoimmune disease.
2. It is a systemic rheumatic disease.
3. The etiology is unknown, but the primary defect is in the immune system.
4. 50 to 70 new cases are diagnosed per year per million people.
5. The range of the disease is:
   1. Mild, limited to a photosensitive facial rash and transient diffuse arthritis.
   2. Life-threatening involvement of:
      1.  Kidneys.
      2. Cardiovascular system.
      3. Respiratory system.
      4. Central nervous system.

What is the mechanism of the LE cell phenomenon?

1. A LE cell is either a normal segmented white blood cell or another phagocytic cell with an engulfed homogeneous and swollen nucleus.
2. This is a degenerating nucleus, which may be in white blood cells or lymphocytes.
3. In SLE, there are various self-antigens like:
   1. Nuclear histones and proteins.
   2. IgG
   3. RBCs
   4. DNA and RNA
   5. Platelets.

What is the mechanism of injury in SLE?

1. Autoantibodies form against all the above antigens.

2. Autoantibodies give rise to an Ag+Ab complex, leading to damage by Type 3 and Type 2 hypersensitivity reactions.

3. Antinuclear antibodies cause damage to the nucleus, which degenerates and gives rise to a homogeneous body called a hematoxylin body.
4. Mature neutrophilic polymorphonuclear leukocyte phagocytizes a spherical, homogeneous-appearing inclusion (hematoxylin body).
5. This is a neutrophil leucocyte with a homogeneous red-purple inclusion that distends the cell and pushes the nucleus to one side.
6. This inclusion is derived from the nuclear material of degenerating leukocytes as the outcome of antibodies against the nuclear material.
7. These inclusions are characteristic of lupus erythematosus but are also found in other autoimmune diseases.

What is the procedure for the LE Cell Phenomenon?

1. Take 5 to 10 mL of blood.
2. Add glass beads or traumatize the cells with a glass rod.
3. Incubate for 20 to 30 minutes at 37 °C.
4. LE cells form during incubation.
5. Bone marrow may be taken for this phenomenon.
6. Centrifuge the blood sample and make a slide from the buffy coat or the area of the white cells.

What is the result of the LE cell phenomenon?

1. The neutrophils show intracytoplasmic inclusions, pushing the homogeneous degenerated nucleus to the periphery.
2. LE cells may be found in CSF, Joint, pleural, pericardial fluid, and blister fluid smears.
3. Now, this test is obsolete because of so many other diagnostic tests.

What are the conditions where Positive LE cells are seen?

1. Systemic lupus erythematosus. These are positive in 95% of the cases.
2. Drug-induced lupus erythematosus. These are seen in 80% to 95% of cases.
3. Other autoimmune diseases show LE cells in less than 20% of the cases.

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