Diseases of the blood Flashcards
Function of blood
- Transport oxygen, Nutrients
- Remove waste
- Transport host defenses
- Ability to carry
- Ability to self repair
Components of blood
45% cells (rbc wbc platelets)
55% plasma (proteins, water, electrolytes, lipids, nutrients)
what are thrombocytes
- Platelets = thrombocytes
functions of the plasma proteins
Albumins = osmotic pressure
Globulins = antibodies and transport proteins
Fibrinogens = blood clotting
PLT?
PLT platelets
PCV
PCV packed cell volume
HCT
HCT haematocrit
MCV
mean cell volume = avg size, vol of rbc
What does mcv tell you?
MCV can help you tell you the cause of the anaemia is
what does high HCT tell you?
high HCT/pcv MAY indicate dehydration
low HCT/pcv MAY indicate anaemia
Anaemia
Anaemia = low haemoglobin, does NOT say anything about the number of rbcs present
Leukopenia
Leukopenia = low wcc
Thrombocytopenia
Thrombocytopenia = low platelets
Pancytopenia
Pancytopenia = low number of all cells (may indicate bone marrow failure)
Polycythaemia
Polycythaemia = raised haemoglobin, does NOT say anything about the number of rbcs present
Leucocytosis
Leucocytosis = raised wcc
penia = low
themia = high
Thrombocythemia
Thrombocythemia = raised platelets
Acute porphyria triggered by?
drugs, LA
what are the clinical implications of porphyria?
- Blood pressure/ HR control affected may be fatal
- Seizures
- Motor and sensory changes
- Hypertension high BP
- Tachycardia fast HR
- photosensitive rash
when would one require a blood transfusion?
blood has to be replaced quickly
bone marrow cannot produce blood cells
rhesus disease
o Mother rhd –
o Baby rhd +
o Mother rhd antibodies attack baby
- O universal donor - AB universal recipient
A has A1 and A2
why shld blood transfusion be avoided if possible ?
o Incompatibility
o Infection like BBV, hep b/c
o RBC lysis
o Prion diseases
o Bacterial infections
o Heart failure from increased volume
Process of transfusion
- Sample
- Tested against ABO and rhesus
- Sample tested against donor sample
- No coagulation or RBC lysis = success
causes of anaemia (reduced haemaglobin)
- production issues (rbc prod, heam prod, globin chains prod)
- increased losses (blood loss etc)
- increased demand (growth and pregnancy)
types of production failure that causes anaemia
type 1
marrow fail to prod rbc to package haemoglobin into
type 2
inability to form haem - deficiency state
type 3
inability to form correct globin chains - thalassaemia or sickle cell
what is Hematinic deficiency?
iron
vitamin b12
folic acid aka folate
effects of thalassaemia
splenomegaly*
cirrhosis*
anaemia
marrow hyperplasia
gallstones
why might blood transfusion not work on thalassemia patients?
patient alr has normal haem levels, might result in haem/iron overload -> cirrhosis
whats splenomegaly caused by?
Splenomegaly since spleen used to recycle rbc, high turnover rate of rbc, higher reprocessing rate
is sickle cell homozygous or heterozygous dominant/ recessive?
homozygous recessive
effects of SCD
o anaemia
o episodes of severe pain
o cells change shape after oxygen has been released. The red blood cells then stick together, causing blockages in the small blood vessels.
what can cause achlorhydria
drugs such as proton pump inhibitors
whats achlorhydria?
Reduced iron absorption
(lack of stomach acid therefore no conversion of Fe3+ to 2+, no absorption of nonheme iron)
possible cause of iron deficiency
how does SCD cause ischaemia and tissue necrosis?
change in shape of rbc causes the blockage of blood vessels
ischaemia is a restriction in blood supply to any tissue, muscle group, or organ of the body, causing a shortage of oxygen that is needed for cellular metabolism
pain and necrosis results
how is heme iron and non heme iron absorbed
heme iron - transporter in intestinal wall
nonheme iron - converted from fe3+ to fe2+ by gastric acids before it can be absorbed by transporters
causes of Reduced iron absorption
- Achlorhydria (lack of stomach acid therefore no conversion of Fe3+ to 2+, no absorption of nonheme iron)
- Coeliac disease
causes of iron loss
Hidden
- Gastric erosions
- Gastric ulcers
- Inflammatory bowel disease
- Crohns
- Ulcerative colitis
- Bowel cancer
Non hidden
- Haemorrhoids produce fresh blood can see
how is b12 absorbed?
Intrinsic factor by parietal cells
Binds to B12
Passes to terminal ileum, absorbed specifically by a transporting system
causes of lack of b12
Lack of intrinsic factor
Strict vegans – lack intake of b12 from meat
Disease of terminal ileum like Crohn’s
causes of lack of folate
- Lack intake
- Jejunal diseases like coeliac
alpha
beta
gamma Hb
function of each
alpha throughout life
beta - after birth
gamma - removes oxygen from maternal circulation for baby, reduced to none after birth
cause of Macrocytic rbc
B12, folate deficiency
cause of microcytic rbc
iron deficiency, thalassemia
normoytic cells anaemia
(GI) bleeding, renal, chronic diseases
Hypochromic
= less red, more pale due to less Hb
what cells are usually hypochromic
microcytic and hypochromic
since there is a iron deficiency, there is less haem, less colour
Ansiocytic
Ansiocytic = very big cells and very small cells in same sample
what do reticulocytes do to the MCV?
raises the mcv
The reticulocytes are released prematurely and still have organelles, are larger than normal rbc, increased MCV.
signs of anemia
- Pale (mucosa)
- Tachycardia
- Sometimes enlarged liver and spleen
- Smooth tongue and loss of papilla
- Beefy tongue
what clinical manifestation of vit b12 deficiency
beefy togue
Dental clinical signs of iron deficiency
- Mucosal atrophy
- Candidiasis
- Recurrent oral ulcers
- Sensory changes
- Smooth tongue
- Loss of papilla
tests for anaemia
- Full blood count
- Haematinics
- GI blood loss endoscopy
- Kidney function
- Liver function
- Bone marrow examination
treatment for anaemia
- Replace haematinics
- Transfusion for rbc production failure
- Erythropoietin for production failure and renal disease
normal ferritin levels
a. 41-400microgram/L
common causes of blood loss
a. Young -> alcohol related gastritis, menstrual, blood donations
b. Old -> GIT, peptic ulcers, bowel cancer, NSAIDs, haemorrhoids, rectal bleeding, chronic kidney or liver disease, fragile blood vessels
chronic kidney disease linked to erthyropoetiin then cannot make rbc
normal value for mcv
80-100fl
normal value for hb
male 140
female 120g/L
normal value for rcc
men – 4.0 to 5.9 x 10*12/L
women – 3.8 to 5.2 x 10*12/L
normal value for hct
men range from 41% to 50%
women is 36% to 48%
normal value for plt
150,000 to 450,000 platelets/ ml of blood
what usually causes hematological cancer?
dna mutation, like translocation
switches off TSG or switches on oncogene
leukaemia vs lymphoma
leukemia begins in the bone marrow and affects blood cell manufacturing
lymphoma affects cells in the immune system and tends to be found in the lymph nodes
clinical presentation of leukemia
anemia
neutropenia (infection and reduced neutrophils)
thrombocytopenia (bleeding due to reduced platelets)
pathogenesis of leukamia?
clonal proliferation of leukaemia cells, replacing normal productive bone marrow cells, leading to marrow failure
signs of anaemia
pale
signs of cardiac failure eg tachycardia or breathlessness
nail changes
signs of neutropenia
infections of
mouth
throat
chest
skin
perianal
reactivation of latent infections
- Tb
- HSV
- zoster virus
unusual patterns of infection and rapid spread, fever, chills, unusual pathogens
signs of thrombocytopenia
bleeding,
bruising ,
bleeding on probing
petechiae,
minor cuts fail to clot,
heavy menstral flow = menorrhagia
acute or chronic leuakaemia worse?
acute more life threatening
acute lymphoblastic vs acute myeloid
acute lymphoblastic - kids , quick development, lymphadenopathy common
acute myeloid - elderly
chronic lymphocytic vs chronic myeloid
chronic lymphocytic - b cell, older adults, males, mostly asymptomatic, may not require treatment
chronic myeloid - neutrophils, translocation, older age, male
what happens when lymphocytic turns lyphoblastic
more aggressive, require treatment eg monoclonal antibody treatment
is hodgkin lymphoma more common or non hodgkin
non
symptoms of lymphoma
fever night sweats
weak weight loss
swelling and lumps in neck armpits groin
staging lymhpoma
number of nodes involved
site
extra nodal involvement
systemic symptoms
what is the cure prognosis for hodgkin lymphoma
stage 1 and 2 over 90%
stage 3 and 4 50-70%
older people do less well
hodkin vs non hodgkin lymphoma cell types involved
b and t cells for NHL
reed sternberg cells for HL
causes of non hodgkin lymphoma
persistent low level microbial infection like ebv, hiv -> chronic activation of the lymphoid system
autoimmune diseases like sjogren syndrome, rheumatoid, peptic ulcer
immunosupression
- aids
- drugs from post transplant
lymphoma can follow from tx of other diseases eg. chemo for leukemia can lead to lymphoma development
what is the cure prognosis for non hodgkin lymhpoma?
> 50% will relapse after tx
aggressive disease that is hard to cure
what is induction remission maintenance and relapse
induction = large dose of chemo to remove disease and reset to normal state
remission = normal bone marrow, no disease
maintenance = low level of tx for many years
relapse = return of disease if not fully cured
what does chemo target
cells wil high turnover rate but might cause hairloss and GUT problems since lining of git has higher turnover
what does radiotherapy target
cells with high cell divison rate
cytotoxic effect of ionizing radiation beam, new tech is able to target specific sites , less unwanted side effects
risk of radio and chemotherapy
higher risk of new cancers later in life
how do monoclonal antibodies work?
they kill certain cell groups from circulation by using cell recognition
(artificial monoclonal antibodies have CD antigens to target IL messengers and growth factors, controlling tumour growth)
2 types of haemopoietic stem cells
allogenic from live donor
autologous from ownself
what makes allogenic haemopoietic stem cell transplant so dangerous? (10% mortality)
graft vs host disease (total marrow failure)
since the host needs to total body irradiation before the transplant from a donor, they have zero bone marrow.
if the host body rejects the graft and starts attacking host, host has zero bone marrow and will die
Definition of leukaemia
Bone marrow malignancy which causes Disseminated neoplastic proliferation of wbc