Extract
Diurnal variation in white blood cells (WBC), particularly neutrophils, is well-described [1]. WBC levels are lower in the morning and increase through the day [1, 2]. Drugs with immunosuppressive effects, such as sirolimus, may further lower WBC counts. This phenomenon has been observed in clozapine and related atypical antipsychotic medications, drugs with known immunosuppressive effects [3, 4]. For patients receiving these drugs, blood counts measured in the early morning may lead to a false impression of low WBC/neutrophil counts (“pseudoleukopenia/pseudoneutropenia”) [4–8] that may result in discontinuation or a reduction in dose and suboptimal treatment. Of importance, isolated morning neutropenia is not known to increase the risk of infection [6, 9].
Abstract
In lymphangioleiomyomatosis patients receiving sirolimus treatment, transient leukopenia in the morning may be due to circadian rhythm, with leukocyte counts recovering later in the day, indicating that a decrease in drug dose may not be warranted http://ow.ly/jPFz30iysgV
Acknowledgements
We thank the LAM Foundation and the Tuberous Sclerosis Alliance for their assistance in recruiting patients for our studies. We thank Henry Masur of the Critical Care Medicine Department at the NIH Clinical Center (Bethesda, MD, USA) for his advice and support.
Footnotes
This article has supplementary material available from openres.ersjournals.com
Support statement: This study was funded by the Intramural Research Program, NIH, National Heart, Lung, and Blood Institute (95-H-0186), and the NIH Medical Research Scholars Program, a public–private partnership supported jointly by the NIH and generous contributions to the Foundation for the NIH from the Doris Duke Charitable Foundation, the American Association for Dental Research, the Colgate-Palmolive Company, Genentech, and other private donors. For a complete list, visit the Foundation website at http://www.fnih.org. Funding information for this article has been deposited with the Crossref Funder Registry.
Conflict of interest: None declared.
- Received October 2, 2017.
- Accepted February 2, 2018.
- The content of this work is not subject to copyright. Design and branding are copyright ©ERS 2018
This article is open access and distributed under the terms of the Creative Commons Attribution Non-Commercial Licence 4.0.