TY - JOUR T1 - Pseudoneutropenia in lymphangioleiomyomatosis (LAM) patients receiving sirolimus: evaluation in a 100 patient cohort JF - ERJ Open Research JO - erjor DO - 10.1183/23120541.00121-2017 VL - 4 IS - 1 SP - 00121-2017 AU - Vissagan Gopalakrishnan AU - Amanda M. Jones AU - Patricia Julien-Williams AU - Tania Machado AU - Robert L. Danner AU - Jeffrey J. Swigris AU - Robert Paine III AU - Jay N. Lozier AU - Joel Moss Y1 - 2018/01/01 UR - http://openres.ersjournals.com/content/4/1/00121-2017.abstract N2 - 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].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/jPFz30iysgVWe 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. ER -