Read our clinical feature on haematology
| Test your knowledge |
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| Question 1 |
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Question 1. An 83-year-old gentleman presents to your practice with gradual worsening SOB and lethargy. His medication includes levothyroxine and simvastatin. Blood test results:
Is this:
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Answer: b This is most likely pernicious anaemia. There is a macrocytic anaemia with low B12 level and elevated MMA. Even though both intrinsic factor and parietal cell antibodies are negative, we know that intrinsic factor is only present in approximately 50 per cent of patients and parietal cell antibodies highly non-specific. In this instance B12 levels are so low that MMA does not add to diagnosis. Without the presence of antibodies one cannot say this is definitely pernicious anaemia, however the absence of antibodies does not mean this is not pernicious anaemia. His history of hypothyroidism makes pernicious anaemia (another autoimmune disorder) most likely. |
| Question 2 |
| Question 2: What is your immediate management?
a. Referral to haematology b. Admission to A&E c. Single lM dose of hydroxocobalamin d. Commence oral cobalamin |
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Answer: c Anaemia in B12 deficiency develops slowly. So long as this patient is not haemodynamically compromised he does not warrant admission to A&E. He will benefit from a single IM dose of hydroxocobalamin which will correct the anaemia. He may be a candidate for subsequent oral replacement. |
| Question 3 |
| Question 3: If a patient has a low B12 level, high MMA level, positive gastric parietal antibodies and negative intrinsic factor antibodies - how often would you test for intrinsic factor antibodies?
a. Repeat until positive result b. Once only c. Twice to confirm assay result. |
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Answer = b Once only as the test is specific. Repeated screening for the development of intrinsic factor antibodies is unnecessary and will not make a difference in the clinical management of the patient if there is a high index of suspicion that the diagnosis is pernicious anaemia. |
