CellMasters 2025
CellWiki
Hematology
Too much of a good thing
A 50-year-old man reports to the Emergency Room because he suffered a severe nosebleed during the night that proves difficult, if not impossible, to stop. Shaving cuts also tend to bleed much longer than he is used to. He has been feeling unwell for about two weeks and is mainly very tired. He easily feels out of breath when walking up stairs. He is not experiencing night sweats, fever or recent weight loss.
A CT scan was performed, which revealed several slightly enlarged lymph nodes in the neck, chest and abdomen. Laboratory test results reveal normocytic anemia, thrombopenia and severe leukocytosis. LDH is elevated. There is no sign of liver damage or kidney dysfunction.
ParameterEDRef.Units
Hemoglobin
3.1
8-10.5mmol/L
MCV
91
83-100fL
Thrombocytes
8
150-400⋅109/L
Leukocytes
134
4-10⋅109/L
Blasts
125
0⋅109/L
Neutrophils
0.8
1.5-6.5⋅109/L
Lymphocytes
8.1
1-3.5⋅109/L
Monocytes
0
0.2-0.9⋅109/L
Eosinophils
0
0-0.4⋅109/L
Basophils
0
0-0.1⋅109/L
AST
33
<35U/L
ALT
34
<45U/L
LDH
564
<248U/L
Creatinine
88
65-115µmol/L
Ferritin
844
30-300µg/L
Folate
34
8.8-60nmol/L
Vitamin B12
331
130-500pmol/L
CRP
24
<8mg/L
Albumin
39
32-48g/L
PT
11.6
9-12sec
PTT
30
24-33sec
Microscopic differentiation of the leukocytes reveals primarily lymphoblasts (~90%). Immunophenotyping is performed to further classify the blasts.
Lymphoblasts in the peripheral blood. More than 20% blasts in blood is sufficient for the diagnosis of acute leukemia. Blast cells are often fragile due to their immaturity, which can cause them to disintegrate in the body. This explains the high LDH.
The patient was given 3 units of RBCs and 1 unit of platelets to supplement his deficiencies. The man’s bleeding was explained by a shortage of platelets rather than clotting factors, as evident by the normal PT and APTT. The neutropenia poses a high risk of bacterial infection, for which prophylactic antibiotics were started.
An acute leukemia is life-threatening because the excessively proliferating cells (in this case the lymphocytes), suppress the production of other cells in the bone marrow. This can result in anemia with a risk of hypoxia and/or thrombocytopenia with a risk of bleeding. Low numbers of neutrophilic granulocytes and monocytes can result in severe infections. Very high numbers of leukocytes can result in blockages in blood vessels (leukostasis), resulting in ischemic and hypoxic tissue.
Immunophenotyping revealed that a large population of B-lymphocytes (~90% of all lymphocytes) with the following markers: CD19+, CD34+, TdT+, CD10+, cycIgM- and CD20-. His treatment is started with dexamethasone and blinatumomab, an antibody that ensures that the B-cells are broken down by the immune system. Although Rituximab is often the first choice for treatment of a B-ALL (CD20 antibody), there is not much point for this patient, as many of the malignant cells do not express CD20.
Therapy may cause a massive destruction of malignant cells. The rapid breakdown of a large number of cells can cause hyperkalemia, which requires periodic monitoring (tumour lysis).
An allogeneic stem cell transplant will be considered once the patient is stable.
Suggest edit
Copy
Download
Open all
Close all