Med D - Haemotology Flashcards
What is blood made out of?
Blood is made of plasma (the liquid of the blood), which contains** red blood cells, white blood cells, platelets and clotting factors**, such as fibrinogen.
Once the clotting factors are removed from the blood, what is left is called the serum. Serum contains:
- Glucose
- Electrolytes, such as sodium and potassium
- Proteins, such as immunoglobulins (antibodies) and hormones
Where do blood cells develop?
in the bone marrow
Where are bone marrow mostly found?
Bone marrow is mostly found in the pelvis, vertebrae, ribs and sternum.
Pluripotent haematopoietic stem cells are )________________ cells that can transform into various blood cells
Pluripotent haematopoietic stem cells are undifferentiated cells that can transform into various blood cells
Pluripotent haematopoietic stem cells are then split into?
- Myeloid stem cells
- Lymphoid stem cells
- Dendritic cells (via different intermediate stages)
Myeloid stem cells split into?
- Megakaryocte
- Erythrocyte
- Myekoblast
Myreloblasts split into?
- basophil
- neurtophile
- eosinophil
- monocyte
–>marcophage
erthyrocyte differentiates into?
RBC
Megakrtyocyte differentiates into?
platelets
Lymphoid stem cells split into?
B cells
T cells
natural killer cells
Red blood cells (RBC) develop from ____________, which originate from myeloid stem cells.
Red blood cells (RBC) develop from reticulocytes, which originate from myeloid stem cells.
What are the retoculocytes?
Reticulocytes are immature red blood cells.
B lymphocytes (B cells) mature in the bone marrow and differentiate into:
Plasma cells
Memory B cells
Where do T cells mature
in the thymus gland
T lymphocytes (T cells) mature in the thymus gland and differentiate into:
- CD4 cells (T helper cells)
- CD8 cells (cytotoxic T cells)
- Natural killer cells
What is a blood film?
A blood film involves the manual examination of the blood using a microscope, looking for abnormal shapes, sizes and inclusions (contents) of the cells.
Name some abnormal findings on a blood film?
Anisocytosis
Target cells
Heinz bodies
Howell-Jolly bodies
Reticulocytes
Schistocytes
Sideroblasts
Smudge cells
Spherocytes
What is Anisocytosis
What can this been seen in?
Anisocytosis refers to a variation in the size of the red blood cells
These can be seen in myelodysplastic syndrome and many types of anaemia (e.g., iron deficiency, pernicious and autoimmune haemolytic anaemia).
What are target cells
What do target cells suggest on blood film>
Target cells are red blood cells with a central pigmented area surrounded by a pale area, surrounded by a ring of thicker cytoplasm on the outside. They look like a bull’s eye target.
These are mostly seen in iron deficiency anaemia and post-splenectomy.
What are Heinz bodies
WHat are they seen in
Heinz bodies are individual blobs (inclusions) seen inside red blood cells. These blobs are denatured (damaged) haemoglobin.
They are mostly seen in G6PD deficiency and alpha-thalassaemia.
What are Howel-Jolly bodies
What are they seen in?
Howell-Jolly bodies are individual blobs of DNA material seen inside red blood cells. The spleen would Normally remove red blood cells with this DNA material inside.
They are seen in patients after a splenectomy or with a non-functioning spleen (e.g., caused by sickle cell anaemia). They are also seen in severe anaemia, where the body is regenerating red blood cells very fast.
What are Reticulocytes seen in
haemolytic anaemia
What are Schistocytes
Schistocytes are fragments of red blood cells. They indicate that red blood cells are being physically damaged during their journey through the circulation.
What are the sideroblasts?
What are they seen in?
Sideroblasts are immature red blood cells with a nucleus surrounded by iron blobs. Sideroblastic anaemia occurs when the bone marrow cannot incorporate iron into the haemoglobin molecules.
This is due to either a genetic defect or myelodysplastic syndrome.
______ ______ are ruptured white blood cells that occur while preparing the blood film when the cells are aged or fragile. They are particularly associated with _______ _____________ ______.
Smudge cells are ruptured white blood cells that occur while preparing the blood film when the cells are aged or fragile. They are particularly associated with chronic lymphocytic leukaemia.
What are Spherocytes
What are they seen in?
Spherocytes are sphere-shaped red blood cells without the bi-concave disk shape.
They can indicate autoimmune haemolytic anaemia or hereditary spherocytosis.
What is leukaemia?
Leukaemia is cancer of a particular line of stem cells in the bone marrow, causing unregulated production of a specific type of blood cell.
The types of leukaemia can be classified depending on how rapidly they progress (chronic is slow and acute is fast) and the cell line that is affected (myeloid or lymphoid) to make four main types:
- Acute myeloid leukaemia (rapidly progressing cancer of the myeloid cell line)
- Acute lymphoblastic leukaemia (rapidly progressing cancer of the lymphoid cell line)
- Chronic myeloid leukaemia (slowly progressing cancer of the myeloid cell line)
- Chronic lymphocytic leukaemia (slowly progressing cancer of the lymphoid cell line)
Most types of leukaemia occur in patients over ___ ___. The exception is _____ _________ ________, which most commonly affects children under ____ years.
Most types of leukaemia occur in patients over 60-70. The exception is acute lymphoblastic leukaemia, which most commonly affects children under five years.
Which leukaemia is the most common leukaemia in children and is associated with Down syndrome
Acute lymphoblastic leukaemia
Which leukaemia is associated with warm haemolytic anaemia, Richter’s transformation and smudge cells
Chronic lymphocytic leukaemia
Which leukaemia has three phases, including a long chronic phase, and is associated with the Philadelphia chromosome
Chronic myeloid leukaemia
Which leukaemia may result in a transformation from a myeloproliferative disorder and is associated with Auer rods
Acute myeloid leukaemia
What is the patho of leukaemia?
A genetic mutation in one of the precursor cells in the bone marrow leads to excessive production of a single type of abnormal white blood cell.
The excessive production of a single type of cell can suppress the other cell lines, causing the underproduction of different cell types. This can result in pancytopenia, which is a combination of low red blood cells (anaemia), white blood cells (leukopenia) and platelets (thrombocytopenia).
The presentation of leukaemia is relatively non-specific. An urgent full blood count is required when leukaemia is a differential for a presentation. Potential presenting features include:
- Fatigue
- Fever
- Pallor due to anaemia
- Petechiae or bruising due to thrombocytopenia
- Abnormal bleeding
- Lymphadenopathy
- Hepatosplenomegaly
- Failure to thrive (children)
One key presenting feature of leukaemia is bleeding under the skin due to ________________
thrombocytopenia
Bleeding under the skin causes ________ _______ _________.
Bleeding under the skin causes non-blanching lesions.
Bleeding under the skin causes non-blanching lesions. These lesions are called different things based on the size of the lesions:
- Petechiae are less than 3 and caused by burst capillaries
- Purpura are 3 – 10mm
- Ecchymosis is larger than 1cm
The top differentials for a non-blanching rash caused by bleeding under the skin are:
- Leukaemia
- Meningococcal septicaemia
- Vasculitis
- Henoch-Schönlein purpura (HSP)
- Immune thrombocytopenic purpura (ITP)
- Thrombotic thrombocytopenic purpura (TTP)
- Traumatic or mechanical (e.g., severe vomiting)
- Non-accidental injury
The NICE guidelines on suspected cancer (2021) recommend a ______ ______ ________ within 48 hours for patients with suspected leukaemia. They recommend children or young people with ________ or ________________ are sent for immediate specialist assessment.
The NICE guidelines on suspected cancer (2021) recommend a full blood count within 48 hours for patients with suspected leukaemia. They recommend children or young people with petechiae or hepatosplenomegaly are sent for immediate specialist assessment.
Ix for leukaemia?
FBC
Blood Film
Lactate dehydrogenase (LDH)
Bone marrow biopsy
CT/PETscane
Lymphnode biopsy
Genetic tests
Bone marrow biopsy is usually taken from the _____ _____
Bone marrow biopsy is usually taken from the iliac crest.
What is the difference between bone marrow aspiratoin and trephine?
Bone marrow aspiration involves taking a liquid sample of cells from within the bone marrow. Bone marrow trephine involves taking a solid core sample of the bone marrow and provides a better assessment of the cells and structure.
What is Acute Lymphoblastic Leukaemia
Acute lymphoblastic leukaemia (ALL) affects one of the lymphocyte precursor cells, causing acute proliferation of a single type of lymphocyte, usually B-lymphocytes. Excessive accumulation of these cells replaces the other cell types in the bone marrow, leading to pancytopenia.
WHat is the presentation of Acute Lymphoblastic Leukaemia
ALL most often affects children under five but can also affect older adults. It is more common with Down’s syndrome. It can be associated with the Philadelphia chromosome (but this is more associated with chronic myeloid leukaemia).
What is Chronic Lymphocytic Leukaemia
Chronic lymphocytic leukaemia is where there is slow proliferation of a single type of well-differentiated lymphocyte, usually B-lymphocytes. It usually affects adults over 60 years of age. It is often asymptomatic but can present with infections, anaemia, bleeding and weight loss. It may cause warm autoimmune haemolytic anaemia.
What is richter’s transformation?
Richter’s transformation refers to the rare transformation of CLL into high-grade B-cell lymphoma.
What are features of Chronic Lymphocytic Leukaemia
Smear or smudge cells are ruptured white blood cells that occur while preparing the blood film when the cells are aged or fragile. They are particularly associated with **chronic lymphocytic leukaemia. **