Week 19 - Anaemia, CKD, haemophilia, hyposplenism (SCD) Flashcards
what is haemoglobin defined as
a low concentration of haemoglobin in the blood
what is the normal haemoglobin ranges in men and women
Women:
120 – 165 grams/litre
Men: 130 -180 grams/litre
what are the three categories of anaemia and how are they divided
divided based on their mean cell volume
Microcytic anaemia (low MCV)
Normocytic anaemia (normal MCV)
Macrocytic anaemia (large MCV)
what is the pneumonic for remembering the causes of microcytic anaemia
TAILS
what does TAILS stand for - microcytic anaemia
T – Thalassaemia
A – Anaemia of chronic disease
I – Iron deficiency anaemia
L – Lead poisoning
S – Sideroblastic anaemia
what does anaemia of chronic disease often occur with
chronic kidney disease due to reduced production of erythropoietin by the kidneys, the hormone responsible for stimulating red blood cell production
what is the treatment of anaemia of chronic disease
erythropoietin
what are the 3 As and 2Hs of normocytic anaemia
A – Acute blood loss
A – Anaemia of chronic disease
A – Aplastic anaemia
H – Haemolytic anaemia
H – Hypothyroidism
what are the two types of macrocytic anaemia
megaloblastic or normoblastic
what does megaloblastic anaemia result from
impaired DNA synthesis, preventing the cells from dividing normally. rather than dividing, they grow into large abnormal cells
what are the two causes of megaloblastic anaemia
B12 deficiency
folate deficiency
what are the 5 causes of normboblastic macrocytic anaemia
Alcohol
Reticulocytosis (usually from haemolytic anaemia or blood loss)
Hypothyroidism
Liver disease
Drugs, such as azathioprine
what is reticulocytosis
refers to an increased concentration of reticulocytes (immature red blood cells)
when does reticulocytosis happen
when there is a rapid turnover of red blood cells, such as with haemolytic anaemia or blood loss
what are the symptoms of anaemia
Tiredness
Shortness of breath
Headaches
Dizziness
Palpitations
Worsening of other conditions, such as angina, heart failure or peripheral arterial disease
what are the symptoms that are specific to iron deficiency anaemia
Pica (dietary cravings for abnormal things, such as dirt or soil)
Hair loss
what are the generic signs of anaemia
Pale skin
Conjunctival pallor
Tachycardia
Raised respiratory rate
what does koilonychia indicate
Koilonychia refers to spoon-shaped nails and can indicate iron deficiency anaemia
what does angular chelitits indicate
iron deficiency anaemia
what is atrophic glossitis and what can this indicate
Atrophic glossitis is a smooth tongue due to atrophy of the papillae and can indicate iron deficiency anaemia
what does jaundice indicate
haemolytic anaemia
what does bone deformities indicate
thalassaemia
what is indicated for unexplained iron deficiency anaemia to exclude gastrointestinal cancer as a source of bleeding
a colonoscopy and oesophagogoastroduodenoscopy (OGD)
what do oedema, hypertension and excoriations on the skin indicate
chronic kidney disease
what is indicated for unexplained anaemia or possible maliginancy
bone marrow biopsy
what does chronic kidney disease describe
a chronic reduction in kidney function sustained over three months, it tends to be permament and progressive
what factors may speed up the decline and cause CKD
Diabetes
Hypertension
Medications (e.g., NSAIDs or lithium)
Glomerulonephritis
Polycystic kidney disease
what are the signs and symptoms of worsening renal function
Fatigue
Pallor (due to anaemia)
Foamy urine (proteinuria)
Nausea
Loss of appetite
Pruritus (itching)
Oedema
Hypertension
Peripheral neuropathy
what is eGFR base on
the serum creatinine, age and gender
what does the eGFR estimate
the glomerular filtration rate - the rate at which fluid is filtered from the blood into Bowman’s capsule
what is proteinuria quantified with
a urine albumin: creatinine ratio (ACR)
what is microscopic haematuria
when blood is identified on testing but not visible on inspection
what does macroscopic haemoaturia refer to
visible blood in the urine. haematuria can indicate infection, malignancy, glomerulinephritis or kidney stones
when can diagnosis of CKD be made
when there are consistent results over three months of either:
- Estimated glomerular filtration rate (eGFR) is sustained below 60 mL/min/1.73 m2
- Urine albumin:creatinine ratio (ACR) is sustained above 3 mg/mmol
what is the G score based on
the eGFR
what is the A score based on
the albumin:creatinine ratio
what is G1
over 90
what is G5
under 15
what is A1
under 3mg/mmol
what is A3
above 30mg/mmol
what is the definition of accelerated progression
Accelerated progression is a sustained decline in the eGFR within one year of either 25% or 15 mL/min/1.73 m2.
what are the complications of CKD
Anaemia
Renal bone disease
Cardiovascular disease
Peripheral neuropathy
End-stage kidney disease
Dialysis-related complications
what is the equation that can be used to estimate the 5 year risk of kidney failure requiring dialysis
The Kidney Failure Risk Equation can be used to estimate the 5-year risk of kidney failure requiring dialysis.
when does NICE suggest referral to a renal specialist
when:
eGFR less than 30 mL/min/1.73 m2
Urine ACR more than 70 mg/mmol
Accelerated progression (a decrease in eGFR of 25% or 15 mL/min/1.73 m2 within 12 months)
5-year risk of requiring dialysis over 5%
Uncontrolled hypertension despite four or more antihypertensives
what does treating the underlying cause in CKD involve
Optimising diabetic control
Optimising hypertension control
Reducing or avoiding nephrotoxic drugs (where appropriate)
Treating glomerulonephritis (where this is the cause)
what is the target BP and ACR in patients under 80 with CKD
The blood pressure target is less than 130/80 in patients under 80 with CKD and an ACR above 70 mg/mmol.
what medications help slow disease progression in CKD
ACE inhibitors (or angiotensin II receptor blockers)
SGLT-2 inhibitors (specifically dapagliflozin)
what is given for primary prevention of cardiovascular disease in all patients with CKD
atorvostatin 20mg
what is the management of metabolic acidosis
oral sodium bicarbonate
what is the management of anaemia due to CKD
iron and erythropoietin
what is the management of renal bone disease due to CKD
vitamin D, low phosphate diet, and phosphate binders
what does the management of end-stage renal disease involve
Special dietary advice
Dialysis
Renal transplant
when are ACE inhibitors offered to patients with CKD
Diabetes plus a urine ACR above 3 mg/mmol
Hypertension plus a urine ACR above 30 mg/mmol
All patients with a urine ACR above 70 mg/mmol
what needs close monitoring in both CKD and ACE inhibitor use
The serum potassium needs close monitoring, as both CKD and ACE inhibitors can cause hyperkalaemia.
what is the licensed SGLT-2 inhibitor licensed for CKD and who is it offered to
Dapagliflozin is the SGLT-2 inhibitor licensed for CKD. It is offered to patients with:
Diabetes plus a urine ACR above 30 mg/mmol
what may anaemia due to CKD be treated with
Anaemia may be treated with erythropoiesis-stimulating agents, such as recombinant human erythropoietin. Blood transfusions can sensitise the immune system (allosensitization), increasing the risk of future transplant rejection.
what is renal bone disease also known as
Renal bone disease is also known as chronic kidney disease-mineral and bone disorder (CKD-MBD).
what are the three things that renal bone disease involves
High serum phosphate
Low vitamin D activity
Low serum calcium
what does reduced phosphate excretion by diseased kidneys result in
high serum phosphate
what do healthy kidneys do to vitamin D
metabolise vitamin D into its active form
what is active vitamin D essential for
calcium absorption in the intestines and reabsorption in the kidneys
what do the parathyroid glands to in response to the low serum calcium and high serum phosphate
The parathyroid glands react to the low serum calcium and high serum phosphate by excreting more parathyroid hormone, causing secondary hyperparathyroidism. Parathyroid hormone stimulates osteoclast activity, increasing calcium absorption from bone.
why does osteomalacia occur
due to increased turnover of bones without adequate calcium supply
what is osteosclerosis
Osteosclerosis occurs when the osteoblasts respond by increasing their activity to match the osteoclasts, creating new tissue in the bone. Due to the low calcium level, this new bone is not properly mineralised.
what is the finding on spinal X ray of osteomalacia
Rugger jersey spine is a characteristic finding on a spinal x-ray. This involves sclerosis of both ends of each vertebral body (denser white) and osteomalacia in the centre of the vertebral body (less white). The name refers to the stripes found on a rugby shirt.
what does the management of renal bone disease involve
Low phosphate diet
Phosphate binders
Active forms of vitamin D (alfacalcidol and calcitriol)
Ensuring adequate calcium intake
what is osteoporosis treated with
bisphosphonates
what is haemophilia A caused by
a deficiency of factor VIII
what is haemophilia B caused by and what is it also known as
Haemophilia B (also known as Christmas disease) is caused by a deficiency in factor IX.
what kind of disorders are haemophilia A and B
both X linked recessive diseases
explain the X linked recessive characteristic of haemoplilia A and B
Both haemophilia A and B are X-linked recessive diseases. All X chromosomes need to have the abnormal gene to have haemophilia. Males only have one X chromosome and require only one abnormal copy to have the disease. Females have two X chromosomes, so when one copy is affected, they are asymptomatic carriers of the gene.
how does haemophilia present in neonates and early childhood
Most cases present in neonates or early childhood. It can present with intracranial haemorrhage, haematomas and cord bleeding in neonates.
what is diagnosis of haemophilia based on
Diagnosis is based on bleeding scores, coagulation factor assays and genetic testing.
what is the management of haemophilia A and B
The affected clotting factors (VIII or IX) can be given by intravenous infusion, either regularly or in response to bleeding.
A complication of this treatment is the formation of antibodies (called inhibitors) against the treatment, resulting in it becoming ineffective.
what is sickle cell anaemia
a genetic condition that causes sickle (crescent) shaped red blood cells
what kind of condition is sickle cell anaemia
Sickle cell anaemia is an autosomal recessive condition affecting the gene for beta-globin on chromosome 11. One abnormal copy of the gene results in sickle-cell trait. Patients with sickle-cell trait are usually asymptomatic. They are carriers of the condition. Two abnormal copies result in sickle-cell disease.
where is sickle cell disease the most common and why
Sickle cell disease is more common in patients from areas traditionally affected by malaria, such as Africa, India, the Middle East and the Caribbean. Having one copy of the gene (sickle cell trait) reduces the severity of malaria. As a result, patients with sickle cell trait are more likely to survive malaria and pass on their genes. Therefore, there is a selective advantage to having the sickle cell gene in areas of malaria, making it more common.
what is the screening programme for sickle cell disease
Sickle cell disease is tested for on the newborn blood spot screening test at around five days of age.
Pregnant women at high risk of being carriers of the sickle cell gene are offered testing.
what does a sickle cell crisis refer to
a spectrum of acute exacerbations caused by sickle cell disease
how are sickle cell crisis managed
Low threshold for admission to hospital
Treating infections that may have triggered the crisis
Keep warm
Good hydration (IV fluids may be required)
Analgesia (NSAIDs should be avoided where there is renal impairment)
what is a vaso-occlusive crisis
most common type of sickle cell crisis.
it is caused by the sickle shaped red blood cells clogging capillaries causing distal ischaemia
how do vaso-occlusive crisis present
It typically presents with pain and swelling in the hands or feet but can affect the chest, back, or other body areas. It can be associated with fever.
what does a vaso-occulsive crisis cause in men
It can cause priapism in men by trapping blood in the penis, causing a painful and persistent erection. Priapism is a urological emergency, treated by aspirating blood from the penis.
what is a splenic sequestration crisis caused by
red blood cells blocking blood flow within the spleen
it causes an actuely enlarged and painful spleen
what does blood pooling in the spleen lead to
severe anaemia and hypovolaemic shock
what can splenic sequestration crisis lead to
splenic infarction, leading to hyposplenism and susceptibility to infection, particularly by encapsulated bacteria
what prevents sequestration crises and may be used in recurrent cases
splenectomy
what does an aplastic crisis describe
Aplastic crisis describes a temporary absence of the creation of new red blood cells. It is usually triggered by infection with parvovirus B19.
what does an aplastic crisis lead to
It leads to significant anaemia (aplastic anaemia). Management is supportive, with blood transfusions if necessary. It usually resolves spontaneously within around a week.
what is acute chest syndrome
Acute chest syndrome occurs when the vessels supplying the lungs become clogged with red blood cells. A vaso-occlusive crisis, fat embolism or infection can trigger it.
how does acute chest syndrome present and what is seen on CXR
Acute chest syndrome presents with fever, shortness of breath, chest pain, cough and hypoxia. A chest x-ray will show pulmonary infiltrates.
what is the general management of sickle cell disease
Avoid triggers for crises, such as dehydration
Up-to-date vaccinations
Antibiotic prophylaxis to protect against infection, typically with penicillin V (phenoxymethylpenicillin)
Hydroxycarbamide (stimulates HbF)
Crizanlizumab
Blood transfusions for severe anaemia
Bone marrow transplant can be curative
how does hydrocycarbamide work
Hydroxycarbamide works by stimulating the production of fetal haemoglobin (HbF). Fetal haemoglobin does not lead to the sickling of red blood cells (unlike HbS). It reduces the frequency of vaso-occlusive crises, improves anaemia and may extend lifespan.
what is crizanlizumab and how does it work
Crizanlizumab is a monoclonal antibody that targets P-selectin. P-selectin is an adhesion molecule found on endothelial cells on the inside walls of blood vessels and platelets. It prevents red blood cells from sticking to the blood vessel wall and reduces the frequency of vaso-occlusive crises.
