Diabetes Mellitus Tutorial Flashcards
28F - presents to A&E with nausea and vomiting. Due to get married in 3 months, lost 1 stone in the last 5 weeks, thinks its due to her personal trainer. However, cancelled her recent gym classes due to tiredness. Blurred vision over the last few weeks. Looks unwell and struggling to hold a conversation due to vomiting.
What do you think are the issues in this clinical case to focus on?
Nausea Vomiting Rapid weightloss Blurred vision - perhaps due to hyperglycaemia Tiredness
Patient demographic - 28F (pregnancy)
What questions would you like to ask her next?
When did the symptoms start?
How long she has had the nausea and vomiting?
How long has she had the blurred vision?
Have you had any other symptoms e.g. excessive thirst, excessive urination, etc?
Have you had diarrhoea?
Have you experience a trauma lately (head trauma)?
Are you pregnant, or do you think you are pregnant?
What is your past medical history?
What is your family history, anyone who has presented with similar symptoms?
Alcohol, drugs, smoking history?
What is your diet like?
Are you periods regular? Are the normal, or heavy? - could point to anaemia = fatigue
EXPLORE THE SYMPTOMS?
Onset, speed of onset, duration, has this happened before?
Old or new?
Acute or chronic?
How can diabetes cause tiredness / fatigue?
Lack of glucose utility - lack of insulin = lack of glucose uptake by cells
Polyuric = nocturia = disrupts sleep
What can cause blurred vision?
Thyroid disease - hyperthyroidism
Diabetes
Weakness of the extraocular muscles
What is your differential diagnosis and how can it be backed up?
Hyperthyroidism - weightloss, tiredness
Diabetes Mellitus - weightloss, tiredness, and blurred vision
Anaemia - tiredness
Pregnancy - nausea, vomiting, tiredness
Gastrointestinal issue - weightloss, nausea, vomiting
Bulimia - weightloss, nausea, vomiting
Tumour - weightloss and other symptoms depending on what type of tumour and where
Why might it not be:
Hyperthyroidism?
Pregnancy?
Hyperthyroidism - if the crisis is big enough for her to lose a stone in just 5 weeks, would have other prominent symptoms associated with hyperthyroidism
Pregnancy - doesn’t explain her blurred vision or weightloss
More history on 28F:
Waking 3x a night and passing large volumes of urine. Sleeps with large water bottle by her bed. Blurred vision is intermittent, and she finds it difficult to focus on her laptop screen. No change in bowel habit. Reports being treated twice for a urine infection in the last 2 months.
Now that you know more history, how has that helped you with your differential diagnosis?
Diabetes Mellitus (T1DM) - explains all her symptoms = weightloss, blurred vision, polydipsia, nocturia, polyuria = osmotic diuresis, UTIs (diabetes make you more susceptible due to the glucose in the urine)
Unlikely to be gastrointestinal - no change in bowel movements
Why is she likely to have T1DM that T2DM?
Weightloss - common in T1DM not T2DM as lack of insulin affects glucose uptake by cells, GLUT-transporters cannot take up glucose into the T1DM
Glucose urinated out = so calories peed out
Use other sources of energy e.g. fat, ketones etc.
Nausea and vomiting - common in T1DM rather than T2DM as T2DM is a slower progression, T1DM = more acute, presents in typically younger people. Also metabolic ketoacidosis can cause this - ketones being used for brain function as glucose isn’t being used
When can ketone levels increase that is not due to T1DM?
Fasting - lack of glucose ingestion for long periods of time = insulin not released
Glycogen stores deplete
Breakdown of fat, releasing of ketones
Although unlikely to cause acidosis - natural buffering of blood with bicarb
What immediate bedside tests would you wish to perform at this point?
Urine dip test Blood glucose test Blood ketones ABG - pH of the blood HbA1c test
Her blood tests come back:
pH6.9 (7.35-7.45)
Glucose 28 mmol/L
Bicarbonate 5 mmol/L(22-29)
Capillary blood ketones 5.2 mmol/L (<1 mmol/L)
Low bicarb - used up all her bicarb stores to buffer her blood pH
V. high glucose levels
V. high blood ketones
V. low pH
What is responsible for the acidosis and why does this occur?
Ketone bodies - alternative metabolic source to glucose
Insulin deficiency = inability to utilise glucose by cells
Body compensates by lipolysis and proteolysis
What treatment does she need immediately?
Insulin injection
Fluids - she is dehydrated
What else may she need with the immediate treatment plan of insulin and fluids?
Give potassium - insulin drags potassium into cells
At admittance her blood potassium was normal, so now it will be low with the insulin injection
Saline gets supplemented with potassium when potassium levels begin to drop
She improves with treatment over the next 12 hours. Her vomiting has settled and she is eating and drinking normally.
What treatment does she need for discharge
Diet and lifestyle changes
Warn her about hypos
Give insulin injections - how to inject, when to inject, how to dose correctly
Rotate injection sites, inject subcutaneously
Glucose meter - pin prick tests
Complications of diabetes
