Interpreting blood results

Question 1

What can directly cause high haemoglobin?

Answer 1

Dehydration

Diuretic therapy

Question 2

What can cause a secondarily high haemoglobin?

Answer 2

Anoxia: high altitude, hypoxic respiratory conditions, heavy cigarette smoking
Polycythaemia rubra vera

Question 3

What causes a low or high haematocrit?

Answer 3

Low: Anaemia
High: Polycythaemia

Question 4

How does mean corpuscular volume allow classification of anaemias?

Answer 4

Low = microcytic
Normal = normocytic
High = macrocytic

Question 5

What is seen when a patient has low mean corpuscular haemoglobin? Give 2 causes of this

Answer 5

Hypochromia

Iron-deficiency + haemoglobinopathies

Question 6

What is the MCHC low and high in?

Answer 6

Low: iron deficiency or thalassaemia
High: spherocytosis or RBC agglutination

Question 7

What is the red cell distribution width? What may cause this to be high?

Answer 7

measure of the variation in RBC size

iron deficiency, myelodysplastic syndrome + haemoglobinopathies

Question 8

What are the 2 types of thrombocytosis? Give examples of each

Answer 8

Reactive (blood loss, infection, inflammation, post-splenectomy)
Autonomous (genetic abnormalities, malignancies)

Question 9

List 10 causes of thrombocytopenia

Answer 9

Drugs
Foods
Infections
Liver disease (hypersplenism)
Alcohol
Nutrient deficiency
Pregnancy
Bone marrow disorders
Inherited
Bleeding.

Question 10

Give 6 causes of neutrophilia

Answer 10

Bacterial infection
Steroids
Post-surgery
Burns
Vasculitis
Neoplasia

Question 11

Give 4 causes of neutropenia

Answer 11

Infection
Drugs (chemo)
AI e.g. CTD
Hereditary

Question 12

Give 3 types of lymphocytosis

Answer 12

Reactive (viral infection, stress)
Metabolic syndrome
Primary (malignancies)

Question 13

Give 2 causes of lymphopenia

Answer 13

Drugs: steroids + immunosuppressive agents

AI disease

Question 14

Give 4 causes of monocytosis

Answer 14

Chronic infection (TB, syphilis)
IBD
Carcinomas
Myeodysplastic syndromes

Question 15

List 4 causes of eosinophilia

Answer 15

Allergy
Neoplastic
CTD
Parasitic infection

Question 16

List 5 causes of basophilia

Answer 16

Viral infection
Urticaria
Hypothyroidism
Post-splenectomy
UC

Question 17

What can result from acute hyponatreamia?

Answer 17

Cerebral oedema

Question 18

What are 4 causes of hypovolaemic hyponatraemia where sodium is lost through the kidneys?

Answer 18

Addison’s Disease
Diuretics
Kidney Injury
Osmotic diuresis

Question 19

What are 3 causes of hypovolaemic hyponatraemia where sodium is lost non- renally?

Answer 19

D+V
Burns
Fistula

Question 20

List 4 causes of euvolaemia which leave a picture of hyponatramia

Answer 20

SIADH
Hypothyroidism
Glucocorticoid insufficiency
Water intoxication

Question 21

What can cause hypervolaemia and apparent hyponatraemia?

Answer 21

CHF

Hypoalbuminaemia (Cirrhosis/ Nephrotic syndrome)

Question 22

List 3 causes of hypovolaemic hypernatraemia

Answer 22

Fluid loss (D+V, burns)
Diabetes insipidus
Osmotic diuresis

Question 23

Give 2 iatrogenic causes of euvolaemic hypernatraemia

Answer 23

Excess IV crystalloid

Sodium containing drugs

Question 24

List 6 causes of increased renal excretion causing hypokalaemia

Answer 24

Loop + thiazide diuretics
Steroids
Cushings
Conns
Renal tubular acidosis 
Hypomagnesia

Question 25

List 3 causes of increased cellular uptake causing hypokalaemia

Answer 25

Salbutamol Insulin Alkalosis

Question 26

List 3 other causes of K+ loss resulting in hypokalaemia

Answer 26

Intestinal fluid loss Burns Malnutrition

Question 27

List 3 causes of decreased renal excretion causing hyperkalaemia

Answer 27

Acute/ Chronic kidney injury Addisons Drugs (K+ sparing diuretics, ACEi, NSAIDs)

Question 28

List 2 causes of increased cellular release causing hyperkalaemia

Answer 28

Acidosis | Tissue breakdown e.g. rhabdomyolysis

Question 29

What iatrogenic process can cause excess load of potassium?

Answer 29

Massive blood transfusion

Question 30

How is urea formed?

Answer 30

When ammonia is converted in the liver | Urea is excreted in the kidneys

Question 31

List 5 causes of raised urea

Answer 31

``` Dehydration GI bleed Increased protein breakdown (surgery, trauma, infection, malignancy) High protein intake Drugs ```

Question 32

List 3 causes of low urea

Answer 32

Malnutrition Liver disease Pregnancy

Question 33

What are creatine levels specific for?

Answer 33

Kidney injury

Question 34

What does eGFR give an indication of?

Answer 34

Number of functioning nephrons in the kidney

Question 35

What is alanine transferase? What is it used for?

Answer 35

Cytosolic enzyme in liver cells | Marker to assess liver cell damage

Question 36

List 4 common causes of raised ALT

Answer 36

Alcohol Viral hepatitis Steatosis Medications/ toxins e.g. NSAIDs, antibiotics, statins, anti epileptics, anti-TB

Question 37

List 4 less common causes of raised ALT

Answer 37

AI hepatitis Haemochromatosis A1 antitrypsin deficiency Wilsons disease

Question 38

List 4 non hepatic causes of slightly raised ALT

Answer 38

Coeliac disease Strenuous exercise Muscle disease Hypo-/Hyperthyroidism

Question 39

Where is aspartate aminotransferase expressed?

Answer 39

``` Liver Heart Skeletal muscle Kidneys Brain RBC's ```

Question 40

What does a AST:ALT ratio ≥ 2.1 suggest? What does a AST:ALT ratio <2.1 suggest?

Answer 40

>, 2.1: Alcohol related liver disease | < 2.1: Hepatic steatosis or chronic viral hepatitis.

Question 41

List 3 physiological causes of raised ALP

Answer 41

3rd trimester of Pregnancy Adolescents (bone growth) Benign familial

Question 42

List 7 pathological causes of raised ALP

Answer 42

``` Bile duct obstruction Primary biliary cirrhosis Primary sclerosing cholangitis Drug induced cholestasis e.g. anabolic steroids Metastatic liver disease Bone disease e.g. Paget's Heart failure ```

Question 43

List 8 causes of raised GGT

Answer 43

``` Hepatobiliary disease (often with other LFT abnormalities) Pancreatic disease Alcoholism COPD Renal failure Diabetes Myocardial infarction Drugs, e.g. carbamazepine, phenytoin, barbiturates + OCP ```

Question 44

What should be tested to assess the livers functions?

Answer 44

Haem breakdown: Bilirubin Plasma protein production: Albumin Clotting factor production: PT/INR Portal system: platelets (low in portal HTN due to splenic sequestration)