BMJ 2014;349:g6450 doi: 10.1136/bmj.g6450 (Published 4 November 2014)
Page 1 of 1
Letters
LETTERS NEUTROPENIA IN PRIMARY CARE
Many drugs used for rheumatic disease cause neutropenia Christine Fox specialist registrar, Richard Hull consultant rheumatologist Rheumatology Department, Queen Alexandra Hospital, Portsmouth PO6 3LY, UK
We agree with Hay and colleagues that, although neutropenia worries clinicians, it is often an unimportant finding and rarely requires treatment.1
Drug induced neutropenia is common in patients with rheumatic disease. We recognise that this is an increasing problem in primary care. It rarely leads to an alteration in the patient’s management, although it causes concern to non-specialists. We would like to emphasise that neutropenia is common in patients taking methotrexate and the newer biological agents, and that this is likely to increase in frequency in the future. Perhaps the term “anti-rheumatic drugs” in table 2 could have been better phrased as gold and penicillamine are now rarely used in rheumatic disease. We would like to emphasise the role of tocilizumab (a biological agent that inhibits interleukin 6) in inducing neutropenia in our patients.2 Although all agents directed against tumour necrosis factor α can also cause neutropenia, infliximab is the most common one in our practice. Rituximab, which depletes B cells, has also been associated with neutropenia, although the onset is usually late and not thoroughly understood.3 The authors decided not to list cytotoxic drugs in table 2, but the role of methotrexate in causing neutropenia cannot be underestimated, even at the immunosuppressant doses used in
inflammatory arthritis or psoriasis, rather than the dose used in chemotherapy.
In the section on systemic lupus erythematosus, the authors comment that most cases of neutropenia are caused by drugs. This is not what we see in clinical practice. It is well recognised that neutropenia or leucopenia heralds the onset of lupus activity.4 Azathioprine and mycophenolate (also not included in the drug list) can be associated with neutropenia. We agree with the point that a positive antinuclear antibody test is probably an incidental finding in the context of isolated neutropenia. Competing interests: None declared. 1 2
3 4
Hay D, Hill M, Littlewood T. Neutropenia in primary care. BMJ 2014;349:g5340. (11 September.) Maini RN, Taylor PC, Szechinski J, Pavelka K, Bröll J, Balint G, et al. Double-blind randomized controlled clinical trial of the interleukin-6 receptor antagonist, tocilizumab, in European patients with rheumatoid arthritis who had an incomplete response to methotrexate. Arthritis Rheum 2006;54:2817-29. Voog E, Morschhauser F, Solal-Céligny P. Neutropenia in patients treated with rituximab. N Engl J Med 2003;348:2691-4. Newman K, Owlia MB, El-Hemaidi I, Akhtari M. Management of immune cytopenias in patients with systemic lupus erythematosus—old and new. Autoimmun Rev 2013;12:784-91.
Cite this as: BMJ 2014;349:g6450 © BMJ Publishing Group Ltd 2014
[email protected] For personal use only: See rights and reprints http://www.bmj.com/permissions
Subscribe: http://www.bmj.com/subscribe
Page 1 of 1
Letters
LETTERS NEUTROPENIA IN PRIMARY CARE
Many drugs used for rheumatic disease cause neutropenia Christine Fox specialist registrar, Richard Hull consultant rheumatologist Rheumatology Department, Queen Alexandra Hospital, Portsmouth PO6 3LY, UK
We agree with Hay and colleagues that, although neutropenia worries clinicians, it is often an unimportant finding and rarely requires treatment.1
Drug induced neutropenia is common in patients with rheumatic disease. We recognise that this is an increasing problem in primary care. It rarely leads to an alteration in the patient’s management, although it causes concern to non-specialists. We would like to emphasise that neutropenia is common in patients taking methotrexate and the newer biological agents, and that this is likely to increase in frequency in the future. Perhaps the term “anti-rheumatic drugs” in table 2 could have been better phrased as gold and penicillamine are now rarely used in rheumatic disease. We would like to emphasise the role of tocilizumab (a biological agent that inhibits interleukin 6) in inducing neutropenia in our patients.2 Although all agents directed against tumour necrosis factor α can also cause neutropenia, infliximab is the most common one in our practice. Rituximab, which depletes B cells, has also been associated with neutropenia, although the onset is usually late and not thoroughly understood.3 The authors decided not to list cytotoxic drugs in table 2, but the role of methotrexate in causing neutropenia cannot be underestimated, even at the immunosuppressant doses used in
inflammatory arthritis or psoriasis, rather than the dose used in chemotherapy.
In the section on systemic lupus erythematosus, the authors comment that most cases of neutropenia are caused by drugs. This is not what we see in clinical practice. It is well recognised that neutropenia or leucopenia heralds the onset of lupus activity.4 Azathioprine and mycophenolate (also not included in the drug list) can be associated with neutropenia. We agree with the point that a positive antinuclear antibody test is probably an incidental finding in the context of isolated neutropenia. Competing interests: None declared. 1 2
3 4
Hay D, Hill M, Littlewood T. Neutropenia in primary care. BMJ 2014;349:g5340. (11 September.) Maini RN, Taylor PC, Szechinski J, Pavelka K, Bröll J, Balint G, et al. Double-blind randomized controlled clinical trial of the interleukin-6 receptor antagonist, tocilizumab, in European patients with rheumatoid arthritis who had an incomplete response to methotrexate. Arthritis Rheum 2006;54:2817-29. Voog E, Morschhauser F, Solal-Céligny P. Neutropenia in patients treated with rituximab. N Engl J Med 2003;348:2691-4. Newman K, Owlia MB, El-Hemaidi I, Akhtari M. Management of immune cytopenias in patients with systemic lupus erythematosus—old and new. Autoimmun Rev 2013;12:784-91.
Cite this as: BMJ 2014;349:g6450 © BMJ Publishing Group Ltd 2014
[email protected] For personal use only: See rights and reprints http://www.bmj.com/permissions
Subscribe: http://www.bmj.com/subscribe
