Introduction The primary objective of this study was to assess response to plasma exchange (PLEX) in myasthenia gravis (MG) patients with and without autoantibodies (Ab) to acetylcholine receptor (AChR) or muscle‐specific kinase (MuSK). Analysis was also done to determine if correlation existed between sex, early or late onset MG, thymoma, or thymectomy and response to PLEX. Materials and Methods Data was analyzed on 58 consecutive MG patients treated with PLEX. Responses were categorized as complete response, clinical improvement requiring maintenance PLEX, or no/minimal response to PLEX. Results Eighty‐eight percent (51/58) of patients were Ab‐positive; 44 had AChR and 7 had MuSK Ab. Complete response was seen in 26 patients (24 Ab+), 24 remain on maintenance PLEX (19 Ab+), and 2 had no/minimal response (both AChR Ab+). Ab status (P = 0.43), AChR Ab (P = 0.10), MuSK Ab (P = 0.45), early onset MG (P = 0.63), thymoma (P = 0.46), and thymectomy (P = 0.16) were not significantly associated with outcome. Patient sex did show significant association with outcome (P = 0.01), with men more likely to have complete response and women more likely to require maintenance. Late onset MG is significantly associated with higher likelihood of complete response (P = 0.03). Antibody titers declined after PLEX in 83% of patients with complete response, in whom pre‐ and post‐PLEX titers were available (n = 6). Conclusions In conclusion, our study showed 96% response rate to PLEX in MG; however, only patient gender and late onset MG were significantly associated with treatment response.

Mantle cell lymphoma is an aggressive malignant B-cell disorder that often presents with a leukemic picture. Circulating lymphoma cell morphology may vary from small round mature-appearing lymphocytes resembling the lymphocytes of chronic lymphocytic leukemia to large prolymphocytoid or blastoid cells. Rare reports of hyperleukocytosis with leukostasis, treated with leukocytapheresis, are described in patients with prolymphocytoid or blastoid morphology. We report an 88 year old woman with mantle cell lymphoma, hyperleukocytosis (WBC > 400 × 10(3) /µL) with severe respiratory compromise but without interstitial or alveolar infiltrates on radiograph or computerized tomography of the chest. She was afebrile and had no central nervous system signs. Circulating lymphoma cell morphology was predominantly of the small lymphocyte type. A two-whole-blood-volume leukocytapheresis reduced her WBC from 465 to 221 × 10(3) /µL in 150 min. Her respiratory rate decreased from 28/min to 18/min and her arterial oxygen saturation (SpO2 ) rose from 91% to 97% on 6 L/min of oxygen by nasal cannula. Severe breathlessness before the procedure abated completely by the end of the procedure. Respiratory compromise may occur in mantle cell lymphoma with hyperleukocytosis with a mature lymphoma cell phenotype, even without a clear picture of leukostasis. Although the ultimate survival of the patient depends on treatment with chemotherapy, leukocytapheresis for alleviation of symptoms may be warranted and should be considered. Respiratory status and response to leukocytapheresis should be documented with physiological measurements. J. Clin. Apheresis 31:398-402, 2016. © 2015 Wiley Periodicals, Inc.