1st April 2022

A woman is seen by her GP with tiredness and lethargy

A woman is seen by her GP with tiredness and lethargy. She is otherwise fit and well. As a result, some blood tests are sent off to determine if there is an organic cause for her symptoms.

The results are as follows:

• Haemoglobin: 12.3g/dl (normal 12-16)
• White cell count: 6.2×109/L (normal 4.5-11)
• Sodium: 141mmol/L (normal 135-145)
• Potassium: 4.2mmol/L (normal 3.5-5.2)
  
• Bicarbonate: 23mmol/L (normal 22-29)
  
• Urea: 4mmol/L (normal 1.8-7.1)
  
• Creatinine: 52mmol/L (normal 53-97)
  
• Fasting serum glucose: 6.1mmol/L (normal 3.9-7.0)
  
• Triglycerides: 1.2mmol/L (normal <1.7)
  
• High-density lipoprotein: 1.6mmol/L (normal <1.3)
  

She goes on to have an oral glucose tolerance test (OGTT) that comes back as 8.9mmol/L (normal 7.8-11) after 2 hours. 

Which of the following is the most likely cause? 

Select the SINGLE most appropriate option from the list below. Select ONE option only.