So, what did the examiners have to say? (Quite a lot - see below!). Our comments are below the examiners.
FACEM VAQ Exam 2012.1 – Question 5
The overall pass rate for this question was 80/104 (76.9%)
Pass Criteria
Part A: Severe anaemia – microcytic, hypochromic in an otherwise well child. Candidates needed to mention iron deficiency as the most likely cause for this full blood count picture.
Part B: Candidates needed to mention iron studies as an investigation they would undertake.
High Scoring Answers:
Recognition that the process occurring was more likely to be of a chronic nature given the results and clinical picture provided. That the other cell lines were normal, and as such candidates did not include differentials that would be inconsistent with this. They noted that the reticulocyte count was mildly elevated; which would reflect a normal marrow reacting to the anaemic state, or, though less likely, reflect a chronic blood loss or chronic haemolytic situation.
They provided potential causes for the iron deficiency (poor dietary intake – most likely due to reliance on cow’s milk, poor intestinal absorption, chronic blood loss). It was accepted that some candidates would reasonably put forward other differentials for a microcytic, hypochromic anaemia, such as thalassaemia and other appropriate differentials for the mildly raised reticulocyte count. However, these differentials do have some inconsistencies with the results provided. Higher scoring answers also did not include differential diagnoses that were inconsistent with the patient’s age.
With respect to investigations, answers that scored well provided the specifics of what constitutes iron studies and expected findings in an iron deficient child (low serum iron, low serum ferritin, high total iron binding capacity, low transferrin saturation). They also mentioned the use of a peripheral blood film; checking for other trace element deficiencies (Serum folate) and included investigations for other potential differentials: test for faecal occult blood (re: chronic blood loss); Hb electrophoresis (re: thalassaemia) and tests for presence of haemolysis (LDH, haptoglobin, unconjugated bilirubin).
Features of unsuccessful answers
Failure to include Fe deficiency in the differential diagnosis
Classifying the clinical situation as ‘life threatening’ and/or requiring urgent blood transfusion
Overemphasis on conditions such as thalassaemia or haemolysis when these are either unlikely for the clinical scenario (profound anaemia but not unwell), age and would be associated with other overt signs e.g. haemolysis likely jaundiced and significant splenomegaly.
So, what does all of that tell us? A couple of things.
1. The examiners were very big on ensuring the answers correlated with the clinical information given. (If you've ever seen a case of cow's milk anaemia the answer was blaringly obvious). 2. Again, we re-inforce the point that it is fundamentally critical to listen to what the examiners are telling you. 3. Having a customisable list of causes of anaemia and being able to fit to to the clinical information given was the key to passing this question. Again, it's about the application and understanding of knowledge, rather than the knowledge itself per se. 4. Being able to sensibly investigate this child was the key to a high scoring answer. Again, this required steps 1,2 and 3 to be watertight. 5. Finally, you'll note that candidates who failed classified this (well) child as having a life threatening illness. As always, it's important to maintain consultant level perspective.