What are the key investigations to consider for a patient presenting with unexplained anaemia in primary care?

For a patient presenting with unexplained anaemia in primary care, key investigations to consider include:

• Full Blood Count (FBC): This is essential for diagnosing anaemia and monitoring response to treatment ¹. For adults with persistent fatigue, a very urgent FBC (within 48 hours) should be considered to investigate for leukaemia ³.
• Faecal Immunochemical Testing (FIT): Quantitative FIT should be offered for iron-deficiency anaemia ³. It should also be offered for non-iron-deficiency anaemia in people aged 60 and over ³. A FIT result of at least 10 micrograms of haemoglobin per gram of faeces in iron-deficiency anaemia necessitates urgent referral via a suspected cancer pathway for colorectal cancer ¹,². FIT should also be considered for adults aged 60 and over with iron deficiency anaemia or changes in bowel habit, or if tests show occult blood in their faeces, as this may trigger a suspected cancer pathway referral for colorectal cancer ⁴.
• Coeliac Serology: If coeliac serology is positive, referral to gastroenterology is indicated ¹,².
• Targeted Imaging/Endoscopy based on symptoms and age:
  • For women aged 55 and over with low haemoglobin levels and visible haematuria, consider a direct access ultrasound scan ³.
  • For patients aged 55 and over with low haemoglobin levels and upper abdominal pain, consider a non-urgent, direct access upper gastrointestinal endoscopy ³.

Further investigations or specialist referral are indicated if there is a lack of response to oral iron treatment, if the anaemia recurs without an obvious cause, if the type of anaemia is uncertain, or if profound anaemia is accompanied by signs of heart failure ¹,². Specific referral criteria apply based on age, gender, and associated symptoms, particularly for suspected gastrointestinal or gynaecological cancers ¹,².