How can I differentiate between aplastic anaemia and other causes of bone marrow failure in a primary care setting?

In a primary care setting, definitive differentiation between aplastic anaemia and other causes of bone marrow failure is not possible, as this requires specialist investigations NICE CKS Marsh et al. 2009DeZern & Churpek 2021. The role of primary care is primarily to recognise the potential signs of bone marrow failure and facilitate urgent referral to haematology Marsh et al. 2009DeZern & Churpek 2021.

Key indicators that may prompt suspicion of bone marrow failure include:

• Symptoms of anaemia: Patients may present with fatigue, pallor, or shortness of breath, which are common symptoms of low red blood cell counts Marsh et al. 2009. While iron deficiency anaemia is a common cause of anaemia NICE CKS,NICE CKS, unexplained or severe anaemia warrants further investigation.
• Increased susceptibility to infections: Frequent or severe infections, particularly bacterial or fungal, can indicate a low white blood cell count (neutropenia) Marsh et al. 2009.
• Bleeding or bruising: Easy bruising, petechiae, nosebleeds, or prolonged bleeding from minor cuts may suggest a low platelet count (thrombocytopenia) Marsh et al. 2009.

If these symptoms are present, a full blood count (FBC) is the crucial initial investigation in primary care Marsh et al. 2009DeZern & Churpek 2021. The hallmark of bone marrow failure, including aplastic anaemia, is pancytopenia, which is a reduction in all three major blood cell lines: red blood cells, white blood cells, and platelets Marsh et al. 2009DeZern & Churpek 2021. Other causes of pancytopenia, such as myelodysplastic syndromes, severe megaloblastic anaemia, or certain viral infections like parvovirus B19, would also need to be considered by specialists NICE CKS Marsh et al. 2009DeZern & Churpek 2021.

Upon finding unexplained pancytopenia, an urgent referral to a haematologist is essential for further evaluation Marsh et al. 2009DeZern & Churpek 2021. The definitive diagnosis and differentiation from other bone marrow disorders, including aplastic anaemia, typically involve a bone marrow aspiration and biopsy, which is performed in secondary care Marsh et al. 2009Barone et al. 2015DeZern & Churpek 2021.