haematology Flashcards

Question

Haemolytic anaemia: aetiology?

Answer 1

1. sickle cell anaemia 2. alpha thalassaemia 3. beta thalassaemia 4. malaria 5. G6PDeficiency

Answer 2

???????????? A haemoglobin disorder of quality. HbS polymerises -> sickle shaped RBC. Autosomal recessive. Sickle cell disease is homozygous SS. Trauma, cold, stress, exercise.

Answer 3

- african descent - but also in inda, middle east and south europe - AUTOSOMAL RECESSIVE 1 in 4 chance of disease - 50% chance of being a carrier - 1 in 4 chance of being disease free

Answer 4

Heterozygous sickle cell trait? none Carriage offer protection against FALCIPARUM MALARIA!! Homozygous Sickle cell anaemia? - vaso-occlusive crisis - eg pulmonary etc or pain in hands (dactylitis) baso the microvasculature - clots forming there- and in long bones in adults also can = pul hypertension anaemia long-term = growth and development problems, things like cardiomegaly, neurological things

Answer 5

- Blood count: • *Level of Hb is in the range of 60-80 g/L* **• RAISED RETICULOCYTE COUNT** - Sickle cell disease is haemolytic, there is increased degradation of RBC's. *Production therefore increases in order to keep up with degradation and so reticulocyte count is raised.* - Blood films: • **Sickled erythrocytes shown** - Sickle solubility test will be POSITIVE GOLD STANDARD/CONFIRMS DX!!! - **HB ELECTROPHORESIS!!!!** **• Confirms diagnosis!!!!!!!!** • Shows 80-95% HbS and absent HbA • Aim for diagnosis at birth (cord blood) to aid prompt pneumococcal prophylaxis reticulocyte count raised BS Sickle cell disease is haemolytic, there is increased degradation of RBC's. Production therefore increases in order to keep up with degradation and so reticulocyte count is raised.

Answer 6

????????? FOLIC ACID to all haemolysis patients!!!! 1. Transfusion. 2. Hydroxycarbamide. --- to prevent painful crises in people with sickle cell anaemia? 3. Stem cell transplant.

Answer 7

Carriage offers protection against falciparum malaria.

Answer 8

???????????? Glucose-6-phosphate dehydrogenase deficiency is an inborn error of metabolism that predisposes to red blood cell breakdown G6PD protects cells against oxidative damage. G6PD deficiency = decreased levels of reduced glutathione → increased susceptibility to oxidative stress ↓ G6PD → ↓ reduced NADPH → ↓ reduced glutathione → increased red cell susceptibility to oxidative stress G6PD is vital for a reaction that is necessary for RBC’s by providing a NADPH which is used with glutathione to PROTECT the RBC from OXIDATIVE DAMAGE from compounds such as hydrogen peroxide - This inherited enzyme deficiency thus results in reduced RBC lifespan due to oxidant damage - Gene for G6PD is localised to chromosome Xq28 near the factor VIII gene

Answer 9

ACUTE 1. Very painful crisis. 2. Stroke in children. 3. Cognitive impairment. 4. Infections. CHRONIC 1. Renal impairment. 2. Pulmonary hypertension. 3. Joint damage.

Answer 10

Parvovirus is a common infection in children. It leads to decreased RBC production and can cause a dramatic drop in Hb in patients who already have a reduced RBC lifespan. This can be dangerous for someone with sickle cell.

Answer 11

``` ???????? Crises characterised by: 1. Haemolysis. 2. Jaundice. 3. Anaemia. ``` ``` **Fatigue, palpitations, pallor, SOB**!! Most are asymptomatic but may get oxidative crisis due to reduction in glutathione production, this is precipitated by: - Made worse by **ingesting fava beans** - **gallstones** are common - **splenomegaly** may be present - In attacks: - Rapid anaemia - Jaundice - Chronic haemolytic anaemia ```

Answer 12

- Blood count is normal between attacks - Blood film during attack: - ***Heinz bodies on blood fil**ms.* - *Bite cells (cells with an indentation in the membrane)* ***Bite and blister cells*** may also be seen - *Irregularly contracted cells* - *Reticulocytosis - increased reticulocytes* - **G6PD enzyme levels!!!!** - will be LOW (but note, immediately after attack the test may be normal since the oldest RBCs with the least G6PD activity are destroyed selectively - so results may show falsely high concentration of G6PD)

Answer 13

- Stop offending drugs and or fava beans - Blood transfusion may be lifesaving - **Splenectomy is not usually helpful**

Answer 14

Unique as it causes cerebral malaria - Fatal infection. The parasite matures in RBCs → ‘knobs’ on RBC surface → bind to receptors on endothelial cells in capillaries & venules → bind to non-infected RBCs = ‘Rosetting’ → sequestration in small vessels (including brain, lung) → microcirculation obstructed: tissue hypoxia Unique cerebral malaria, fatal infection. Parasites mature in RBC's, RBC's collect in small vessels and cause blockage of cerebro-microvasculature = hypoxia!

Answer 15

Some species [P. Ovale, P. Vivax] **lay dormant in the live**r & *relaspse by reactivating months later]* - Not eradicated by most conventional anti-malarial treatments NEED TO GIVE THEM CHLOROQUINE AND PRIMAQUINE TO FULLY ERADICATE!!!!

Answer 16

Complicated = Vascular occlusion , drowsiness, increased ICP -> seizures/coma Uncomplicated = Fever with sweats and chills

Answer 17

Diagnosis via *blood film (thick and thin) w/ light microscopy* **Giemsa stain blood smear** **Thick and thin blood smears** (If negative, 2 more films should be sent within 48 hours) - 3 separate films (different times) required to rule out completely 1st smear may be +ve in 95% cases. Thick: sensitive but low resolution, **tell you if you have malaria.** Thin: identify morphological features & quantification of parasitaemia. Identification of species on thin film: Trophozoite most commonly used and rapid antigen test ——**tell you species and parasite count.** OTHER Travel history Rapid diagnostic tests (detect parasitic antigens) PCR FBC, LFTs, U&Es, blood gases, blood culture CXR, lumbar puncture

Answer 18

Symptoms occur from 6 days post infection BUT Vivax and Ovale commonly present 6 months post infection - Febrile paroxysm (10-12 hours of intense rigors, chilss -> high fever, profuse diaphoresis) - haemolytic anaemia - bc malaria parasites infect rbc - at the end of that infection cycle, red blood cell ruptures - process lowers the amount of red blood cells and can in a severe stage cause severe anemia. SIGNS - - Splenomegaly, - **hypovolaemia** - **AKI** - **and nephrotic syndrome** - **Anaemia - (haemolytic anaemia)** - malaria parasites infect rbc - at the end of that infection cycle, *red blood cell ruptures - process lowers the amount of red blood cells and can in a severe stage cause severe anemia.* - Jaundice - Hepatosplenomegaly - Black water Fever - darkened urine - bc of all the haemolysis (baso excreting Hb out of kidneys) SYMPTOMS - Fever, - chills, - malaise, - abdo pain, - diarrhoea, - vomiting, - headache, - cough, - **shortness of breath** - **fits** - confusion - **Fever, haemolysis, chills, sweats, headaches etc.** Non-specific features: - **Anaemia** - **Low platelets** - **Hyperbilirubinaemia** - **Mildly raised transaminases (ALT, AST)**

Answer 19

**Artemisinin combination therapy (ACT)** OR → **PO Chloroquine** **Artemisinin combination therapy (ACT)** → **PO Quinine *(SULPHATE)* & Doxycycline as 2nd agent** **IV Artesunate** → THEN **Artemisinin combination therapy (ACT)** OR **give IV Quinine *(sulphate)***

Answer 20

A haemoglobin disorder of quantity. There is reduced synthesis of one or more globin chains with leading to a reduction in Hb -> anaemia.

Answer 21

Alpha Thalassaemia = Reduced A chain synthesis Beta Thalassaemia = Reduced B chain synthesis They have very few beta chains, alpha chains are in excess Alpha Thalassaemia = gene deletions Beta Thalassaemia = - Caused by over 200 genetic defects

Answer 22

1. Thalassaemia major. 2. Thalassaemia intermedia. 3. Thalassaemia carrier/heterozygote.

Answer 23

When bone marrow stem cells are damaged -> pancytopenia.

Answer 24

- **Blood count:** • Pancocytopenia with low reticulocyte count - **Bone marrow examination:** • Hypocellular marrow with increased fat spaces

Answer 25

Type of megaloblastic anaemia which causes b12 deficiency is an AUTOIMMUNE DISORDER in which the parietal cells of the stomach are attacked (THUS PARIETAL CELL LOSS) resulting in atrophic gastritis and the loss of intrinsic factor production And thus vitamin B12 malabsorption (bit more in notion)

Answer 26

Onset is insidious with progressively increasing symptoms of anaemia e.g. fatigue, headache, pallor, dyspnoea, anorexia, tachycardia and palpitations Red sore tongue (glossitis) and angular stomatitis/cheilosis (ulceration of the corners of the mouth) may be present lemon-yellow skin colour due to the combination of pallor and mild jaundice caused by excess breakdown of haemoglobin (due to fact that body will try to remove defective large RBCs)

Answer 27

BLOODS - **intrinsic factor antibodies**, although found in only 50% of patients with pernicious anaemia are SPECIFIC for DIAGNOSIS ``` - **Blood count & film:** • Typical of megaloblastic anaemia • RBC’s are MACROCYTIC • Peripheral film shows oval macrocytes (large RBC’s) with hypersegmented neutrophil polymorphs with six or more lobes in the nucleus ``` - **Serum bilirubin** may be raised as a result of ineffective erythropoiesis resulting in increased RBC breakdown - **Serum B12** is low - Hb is low - Reticulocyte count is LOW - Intrinsic factor antibodies - DIAGNOSTIC but lower sensitivity i.e. not present in all patients

Answer 28

major - **blood transfusion dependan**t - **chelation agents (deferoxamine** to avoid iron overload) **splenectomy** when splenomegaly causes excessive relies on regular transfusions There is a risk of iron overload from the regular trasnfusions. Excess iron will be deposited in various organs e.g. the liver and spleen and cause fibrosis. These patients usually present very young due to having severe anaemia and so a failure to feed/thrive.

Answer 29

often asymptomatic

Answer 30

1. Raised reticulocyte count. | 2. Microcytic anaemia.

Answer 31

HIV infection is caused by a retrovirus that *infects and replicates in human lymphocytes and macrophages,* eroding the integrity of the human immune system over a number of years, culminating in immune deficiency and a susceptibility to a series of opportunistic and other infections as well as the development of certain malignancies. SERODIFFERENT = When a couple is serodifferent, this means one person is living with HIV and the other person is HIV-negative. SEROCONVERSION Seroconversion is **a sign that the immune system is reacting to the presence of the virus in the body**. It's also the *point at which the body produces antibodies to HIV.* → Once seroconversion has happened, an HIV test will detect antibodies and give a positive result.

Answer 32

- 37.7 million people across the globe with HIV in 2020. - Every day 4000 new HIV infections (adults and children) (2020) - 60% are in sub-Saharan Africa - 10% are among children under 15 years of age - Newly infected people going down - Those living with HIV going up

Answer 33

Virus Most people are infected - through sexual contact; unprotected anal or vaginal sex - before birth or during delivery (35% chance risk of HIV being passed down to child from pregnant mother) - during breastfeeding, - or when sharing contaminated needles and syringes - - receiving unsafe injections, blood transfusions and tissue transplantation, and medical procedures that involve unsterile cutting or piercing; and - experiencing accidental percutaneous needle stick injuries, including among health workers - having another sexually transmitted infection (STI) such as syphilis, herpes, chlamydia, gonorrhoea and bacterial vaginosis;

Answer 34

Retrovirus = RNA virus which uses a reverse transcriptase (RTA) to make a DNA copy that becomes integrated into DNA of host cell 1. HIV **attaches** to and **penetrates** host T cells via CD4+ molecules and chemokine receptors 2. After attachment, HIV RNA and several HIV-encoded enzymes are released into the host cell. 3. Viral replication requires that **reverse transcriptase** (an RNA-dependent DNA polymerase) **copy HIV RNA**, **producing proviral DNA**; this copying mechanism is prone to errors, resulting in frequent mutations and thus *new HIV genotypes.* 4. viral DNA enters the host cell’s **nucleus** and is **integrated into the host DNA** in a process that involves **integrase**, another HIV enzyme. 5. viral HIV DNA can be transcribed to HIV RNA and translated to HIV proteins 6. HIV proteins are assembled into HIV virions at the host cell inner membrane and budded from the cell surface within an **envelop of modified human cell membrane**

Answer 35

Diagnosis is confirmed: - **HIV antibody test** If **seeing recurrent respiratory infections** best to test for HIV to rule it out and or detect it EARLY should be considered in any patient with **unusual or recurrent serious infections without another cause**, *especially in those with risk factors for HIV infection.*

Answer 36

**Acute** - newly confirmed infection: - Start antiretroviral therapy regardless of CD4 count (500< = normal but **<200 = bad) And select antiretroviral therapy regimen (INSTI-based regimen etc) and supportive care (counselling, prophylaxis of opportunistic infections, vaccinations) * *Ongoing** - virological or immunological treatment failure: - Re-assessment of antiretroviral therapy!!!!! Virological failure is defined as the inability to achieve or maintain suppression of viral replication to an HIV RNA level <200 copies/mL Immunological failure is the failure to achieve and maintain an adequate CD4 response despite virological suppression U = U (Undetectable = untransmittable) Without treatment, **HIV infection progresses to AIDS in approximately 10 years**, with death following within three years after onset of AIDS. With appropriate treatment, a 20-year-old with HIV infection can expect to live to reach 71 years of age.

Answer 37

- Advanced HIV disease or **AIDS** – if untreated or non-responsive to therapy. Said to have AIDS if develop: - Opportunistic infections such as pneumocystis pneumonia, cytomegalovirus (CMV) retinitis, and cryptococcal meningitis. - Certain malignancies such as Kaposi’s sarcoma, non-Hodgkin’s lymphoma, and carcinoma of the cervix. - any HIV antibody test would be reliable at this advanced stage *of HIV and the CD4 count is likely to be less than 200 cells per mL*

Answer 38

PreP - for partners - daily dosing and event-based dosing Effectiveness has been demonstrated in MSM (men who have sex with men), heterosexual serodifferent couples, and injecting drug users PEP - 28 days Combination Antiretroviral Therapy - treatment that can stop an HIV infection after the virus has entered a person’s body. It must be taken within 72 hours of exposure

Answer 39

A malignant proliferation of haemopoietic stem cells rapidly proliferating immature blast blood cells in the bone marrow that are non functional i.e. defective the bone marrow is not able to make as many normal functioning cells resulting in fewer functioning blood cells in the blood resulting in the symptoms of leukaemia *soon too many wbc myeloblasts in bone marrow - that they **SPILL INTO BLOOD*** if build-up of myeloblasts = acute myeloid leukaemia if build-up of lymphoblasts = acute lymphoblastic leukaemia -------------thus too little platelets made = thromocytopenia = **bleeding** or too little rbc made = anaemia = **fatigue** or too little neutrophils = neutropenia = **infection**

Answer 40

1. AML - acute myeloid leukaemia. 2. CML - chronic myeloid leukaemia - uncontrolled clonal proliferation of basophils, eosinophils and neutrophils. 3. ALL - acute lymphoblastic leukaemia - uncontrolled proliferation of immature lymphoblast cells. 4. CLL - chronic lymphoblastic leukaemia Proliferation of B lymphocytes leads to the accumulation of mature B cells that have escaped apoptosis.

Answer 41

- Associated with radiation (ionising)** - and syndromes such as **Down’s (trisomy 21)** - Preceding haematological disorders. - Prior chemotherapy

Answer 42

1. Anaemia. - - breathlessness, fatigue, angina and claudication - There is pallor and cardiac flow murmur 2. Infection. - - infections - There is fever and mouth ulcers 3. Bleeding.- bleeding and bruising (first three bc of bone marrow failure) 4. Hepatomegaly. Because of tissue infiltration. 5. Splenomegaly. Because of tissue infiltration. can be Gum hypertrophy

Answer 43

1. Blood film. 2. Bone marrow biopsy. 3. Lymph node biopsy. 4. Immunophenotyping. 5. Cytogenetics. (microscopy

Answer 44

More than 80% have the Philadelphia chromosome which forms a fusion gene BCR/ABL on chromosome 22, which has tyrosine kinase activity - stimulates cell division

Answer 45

- **ALL is mainly seen in childhood**- *most common between 2-4 yo - commonest cancer in childhood* - **CLL** is a disease of the **elderly - most common leukaemia** - occurs mainly in later life - **AML** is commonest acute leukaemia of adults - **CML**- almost exclusively a disease of adults - most often 40-60yrs - *slight* male predominance

Answer 46

- Blood and platelet transfusions - Neutropenia may lead to deadly infections - treat with prophylactic antivirals, antibacterial and antifungals - ALLOPURINOL (prevents tumour lysis syndrome) - IV fluids - insert Hickman line (permanent cannula into main vessel, tunnelled under sub-cutaneous fat so harder for infection to arise) so can easily take blood for testing and administer drugs and fluids - Chemotherapy - Marrow transplantation for CML!!!!!! - * *ORAL IMATINIB -** specific BCR/ABL tyrosine kinase inhibitor BC more than 80% have philadelphia chormosome which has tyrose kinase activity - Stem cell transplant For CLL!!!! also HUMAN IV IMMUNOGLOBULINS

Answer 47

A malignant growth of WBC's predominantly in the lymph nodes. disorders caused by **malignant proliferations of lymphocytes** accumulate in the lymph nodes causing **LYMPHADENOPATHY** (enlarged lymph nodes),

Answer 48

1. Primary immunodeficiency. 2. Secondary immunodeficiency e.g. HIV. 3. Infection e.g. EBV!!!!!!, HTLV-1. 4. Autoimmune disorders e.g. RA. and FHx!!!!

Answer 49

There is impaired immunosurveillance and infected B cells escape regulation and proliferate. (This is just a theory).

Answer 50

1. Enlarged lymph nodes in arm/neck. 2. Symptoms of compression syndromes. 3. General systemic 'B' symptoms e.g. weight loss, night sweats, malaise. 4. Liver and spleen enlargement. hodgkin's: 1. Painless lymphadenopathy. 2. Presence of 'B' symptoms e.g. night sweats, weight loss. Non-hodgkin’s: Nodal disease - superficial lymphadenopathy - pancytopenia (anaemia, infection)

Answer 51

literally same as leukaemia!! 1. Blood film. 2. Bone marrow biopsy. 3. Lymph node biopsy. 4. Immunophenotyping. 5. Cytogenetics. (Raised lactose dehydrogenase = worse prognosis BC increased cell turnover and thus cell proliferation)

Answer 52

Presence of Reed-sternberg cells.

Answer 53

I - Confined to **single lymph node region** II - Involvement of **two or more nodal areas** on the **same side of the diaphragm** III - Involvement of nodes on **both sides of the diaphragm** IV - **Spread beyond the lymph nodes** e.g. *liver or bone marrow* - Each Stage is either A or B: Stage A: no systemic symptoms other than **pruritus (severe itching of skin)** Stage B: presence of B symptoms such as **fever, weight loss and night sweats**

Answer 54

ABVD short course combination chemotherapy followed by radiotherapy. Longer course of ABVD

Answer 55

1. Secondary malignancies - (radiotherapy may increase this risk) 2. IHD. (radiotherapy may increase this risk) 3. Infertility. (Chemo can cause this) 4. Nausea. (Chemo) 5. Alopecia. (Chemo)

Answer 56

- **Low grade** e.g. Follicular Lymphoma - Slow growing - Usually advanced at presentation - Incurable - Median survival 9-11 baso 10 years - **High grade** e.g. Diffuse Large B Cell Lymphoma - Example is Diffuse Large B-cell Lymphoma - Usually has nodal presentation - 1/3 cases have extranodal involvement Aggressive. Nodal presentation, patient unwell. Often curable. **Very high grade e**.g. Burkitt’s Lymphoma

Answer 57

Low grade: If symptomless - do nothing. ——> Radiotherapy, combination chemotherapy and mAb may be used if symptomatic. High grade: - Early: short course chemotherapy and radiotherapy. R-CHOP regimen - Advanced: combination chemotherapy and mAb. R-CHOP regimen: • **R - RITUXIMAB** (monoclonal antibody - minimal side effects) **• C - CYCLOPHOSPHAMIDE** **• H - HYDROXY-DAUNORUBICIN** • **O - VINCRISTINE (Oncovin brand name)** • **P - PREDNISOLONE** rituximab = - Monoclonal antibody - Targets CD20 expressed on cell surface B cells - Chimeric mouse/human protein - Minimal side effects

Answer 58

- **MALE predominance** - Majority of cases occur in TEENAGERS e.g. 13-19 and ELDERLY e.g. over 65 - 2 peaks of incidence; **teenagers and elderly**

Answer 59

Malignancy of plasma cells leading to progressive bone marrow failure. It is associated with production of characteristic paraprotein, bone disease and renal failure.

Answer 60

1. Blood film. Rouleaux formation (aggregations of RBC's). 2. Bone marrow aspirate and trephine biopsy. - Increased plasma cells. 3. Electrophoresis. - Monoclonal protein band. 4. X-ray. 5. CT scan. 6. MRI scan. 7. Chromosomal abnormalities. 8. Urine - (Immunoglobulin light chains with kappa or lamda lineage.) must be evidence of mono-clonality baso when = Abnormal proliferation of a single clone of plasma cell leading to immunoglobulin secretion and causing organ dysfunction especially to the kidney. ``` on blood film: Rouleaux formation (aggregations of RBC's). ```

Answer 61

1. Tiredness. 2. Bone/back pain. 3. Infections. CRAB! 1. Calcium is elevated. 2. Renal failure. 3. Anaemia. normochromic and normocytic!!!! 4. Bone lesions.

Answer 62

Chemotherapy, analgesia and bisphosphonates. (VAD OR CTD CHEMO!!!) Radiotherapy and bone marrow transplant can also be done

Answer 63

1. Deposition of light chain. 2. Hypercalcaemia. 3. Hyperuricaemia.

Answer 64

Paraproteins form aggregates in the blood and change the viscosity.

Answer 65

increased rbc levels due to overproduction by bone marrow | baso having a high concentration of red blood cells in your blood/increase in haematocrit

Answer 66

Primary cause: Polycythaemia rubra vera - over reactive bone marrow. Secondary Causes: 1. Heavy smoking. 2. Lung disease. 3. Cyanotic heart disease. 4. High altitude.

Answer 67

- Blood count: - **Raised white cell count (WCC)** and **increased platelets** = distinguishes PV from other secondary causes - **Raised Hb** (major criteria) - **raised haematocrit** Presence of JAK2 mutation on genetic screen (major criteria) Bone marrow biopsy showing FIBROSIS 1. Hb. 2. RCC. 3. PCV.

Answer 68

1. Itching. (after a hot bath) 2. Headache. 3. Dizziness. 4. Visual disturbance. /blurred vision 5. tired 6. sweating 7. Plethoric complexion (flushed skin) 8. hepatosplenomegaly - due to extramedullary haemopoiesis - bc excess rbc build up in speen 9. Gout and kidney stones 10. more prone to blood clots

Answer 69

- **Venesection:** - Aims to lower PCV and platelet count - **Removal of 400-500mL of blood weekly to relieve symptoms** no cure chemo

Answer 70

normally kidneys produce erythropoietin which binds to haematopoietic stem cell AND ACTIVATES JAK2 GENE → and causes cell to divide and produces more RBC BUT this mutation = the haematopoietic stem cells **DIVIDE even in the absence of erythropoietin** and they become the predominant haematopoietic stem cells →>> and HAEMATOCRIT INCREASES! these *haematopoietic stem cells start to die out* - and SCAR TISSUE FORMS - THUS bone marrow can no longer produce rbcs → = ANAEMIA (low hb/rbc levels)

Answer 71

the most common ***inherited*** cause of ***abnormal bleeding*** (***haemophilia***) involve a deficiency, absence or malfunctioning of a ***glycoprotein*** called VWF

Answer 72

Break down of malignant cells -> | content release -> metabolic disturbances; can cause hyperuricaemia, hyperkalaemia, hypocalcaemia.

Answer 73

—High tumour burden —Pre-existing renal impairment —inc age —high grade disease

Answer 74

- Aggressive hydration - ALLOPURINOL (xanthine oxidase inhibitor) or **RASBURICASE** (recombinant urate oxidase) both work *to reduce uric acid production* - Monitor electrolytes

Answer 75

This is a deficiency of platelets in the blood <150000/ml^3 Can either be due to decreased production or increased destruction ITP - immune thrombocytopenic purpura - TTP - thrombotic thrombocytopenic purpura

Answer 76

1. Production failure e.g. marrow suppression, marrow failure. 2. Increased removal e.g. immune response (ITP), consumption (DIC), splenomegaly.

Answer 77

due to immune destruction of platelets Baso antibodies are produced against platelets - and they get destroyed by body ——> thus = *purpura (*red or purple spots on the skin caused by bleeding underneath skin) The antibody-coated **platelets are removed** after they *bind to Fc receptors on macrophages* **IgG antibodies** form to platelets and megakaryocytes Aetiology: viral infections Malignancy

Answer 78

- Sudden self-limiting **purpura (red or purple spots on the skin caused by bleeding underneath skin)** - **Easy bruising** - **easy bleeding** - TKI - Epistaxis (nose bleed) - Menorrhagia (heavy menstruation) - Gum bleeding

Answer 79

- **Platelet autoantibodies** are detected in about 60-70% of patients, and are presumed to be present, although not detectable in the remaining patients; the antibodies often have specificity for platelet membrane glycoproteins IIb/IIIa and/or Ib - **Bone marrow examination:** • Shows thrombocytopenia with increased or normal megakaryocytes in the marrow ``` MANAGEMENT: - First line: - Corticosteroids e.g. PREDNISOLONE - IV immunoglobulin e.g. IV IgG - raises platelet count more rapidly than steroids - thus useful for surgery ```

Answer 80

Widespread adhesion and aggregation of platelets leads to microvascular thrombosis and thus consumption of platelets and thus profound thrombocytopenia ***Baso** when tiny blood clots develop throughout the **small vessels** of the body* **using up platelets and causing thrombocytopenia***, bleeding under the skin and other systemic issues. It affect the small vessels so it is described as a **microangiopathy**.* blood clots develop due to a problem with a specific protein called ***ADAMTS13*** This protein normally *inactivates von Willebrand factor* and reduces *platelet adhesion* to vessel walls and *clot formation*. A shortage in this protein leads to ***von Willebrand factor overactivity and the formation of blood clots in small vessels***. This causes platelets to be used up leading to thrombocytopenia. The blood clots in the small vessels break up red blood cells, leading to ***haemolytic anaemia***. ANAEMIA + THROMBOCYTOPENIA + AKI!!!