Complications of leukocytapheresis

Apheresis: A cell-based therapeutic tool for the inflammatory bowel disease

Inflammatory Bowel Disease (IBD) is a hallmark of leukocyte infiltration, followed by the release of cytokines and interleukins. Disease progression to Ulcerative Colitis (UC) or Crohn’s Disease (CD) remained largely incurable. The genetic and environmental factors disrupt enteral bacteria in the gut, which hampers the intestinal repairing capability of damaged mucosa. Commonly practiced pharmacological therapies include 5-aminosalicylic acid with corticosteroids and tumor necrosis factor (TNF)-α. New interventions such as CDP571 and TNF-blocking RDP58 report the loss of patient response. This review discusses the non-pharmacologic selective granulocyte–monocyte-apheresis (GMA) and leukocytapheresis (LCAP) that have been proposed as treatment modalities that reduce mortality. GMA, an extracorporeal vein-to-vein technique, presents a strong safety profile case for its use as a viable therapeutic option compared to GMA's conventional medication safety profile. GMA reported minimal to no side effects in the pediatric population and pregnant women. Numerous studies report the efficacious nature of GMA in UC patients, whereas data on CD patients is insufficient. Its benefits outweigh the risks and are emerging as a favored non-pharmacological treatment option. On the contrary, LCAP uses a general extracorporeal treatment that entraps leukocytes and suppresses cytokine release. It has been deemed more efficacious than conventional drug treatments, the former causing better disease remission, and maintenance. Patients with UC/CD secondary to complications have responded well to the treatment. Side effects of the procedure have remained mild to moderate, and there is little evidence of any severe adverse event occurring in most age groups. LCAP decreases the dependence on steroids and immunosuppressive therapies for IBD. The review will discuss the role of GMA and LCAP.

Cytapheresis (CAP) with leukocyte removal filter/bead column as one therapeutic option for inflammatory bowel disease

Inflammatory bowel disease (IBD) like Crohn's disease and ulcerative colitis are chronic inflammatory disorders that affect the bowel. The disease is characterized by periods of clinical remission and relapse due to severe intestinal inflammation. Drug therapy of IBD is associated with unpleasant side effects. Further, efficacies of conventional drugs decrease with chronic use and this can represent a major difficulty in the long term management of IBD. However, in active IBD, leukocytes are elevated in the lesion they may be able to be a factor of IBD aggravation. Membrane filters column and leukocyte adsorbing beads have been developed which are direct blood perfusion systems for removing any desired level of leukocytes. Clinical studies with these two new models have shown good effects for active IBD. Clinical data suggest that leukocytapheresis might be an effective adjunct to therapy of IBD, to promote remission, taper conventional drug dosage and potentially should reduce the number of patients who require colectomy. The results may further understandings of the pathophysiology of IBD and this in turn should contribute to a more effective treatment of this disorder.

Safety and Tolerability of Nafamostat Mesilate and Heparin as Anticoagulants in Leukocytapheresis for Ulcerative Colitis: Post Hoc Analysis of a Large-Scale, Prospective, Observational Study

Nafamostat mesilate is the first anticoagulant of choice for leukocytapheresis (LCAP) with a Cellsorba E column for treating ulcerative colitis (UC). However, because of complications, mainly due to allergy to nafamostat mesilate, heparin may be used as a substitute. To evaluate the safety and tolerability of nafamostat mesilate and heparin as anticoagulants in LCAP for UC, we conducted post hoc analysis of data from a large-scale, prospective, observational study of LCAP, which was conducted at 116 medical facilities in Japan between May 2010 and December 2012. Of 832 patients included in this analysis, nafamostat mesilate and heparin were used in 676 (81.3%) and 113 (13.6%), respectively. There were no significant differences in the incidence of adverse reactions (8.6% vs. 7.1%) and intrafilter pressure increases (12.7% vs. 16.8%) between the nafamostat mesilate and heparin groups. Adverse reactions of hemorrhage or blood pressure decreases associated with heparin use were not observed. There were no significant differences in rates of clinical remission (69.1% vs. 68.1%) and mucosal healing (62.9% vs. 63.6%) between the nafamostat mesilate and heparin groups. Thus, the safety and tolerability were comparable in the nafamostat mesilate and heparin groups, indicating that both nafamostat mesilate and heparin can be well tolerated as anticoagulants in LCAP for UC.

Univariate analysis to examine predictors of response to leukocytapheresis in ulcerative colitis patients

Leukocytapheresis (LCAP) is reportedly effective for the treatment of active ulcerative colitis (UC) and is a therapeutic option for steroid-dependent or steroid-resistant patients with UC. However, a consensus regarding the use of LCAP for UC patients has not yet been established. Therefore, we analyzed patients' records to identify predictors of response to LCAP therapy and subsequent recurrence. Between October 2001 and March 2011, we recruited 41 patients who had been diagnosed as having UC and had received LCAP therapy. Patients diagnosed with moderate to severe UC with left-side or total colitis and received LCAP therapy for the first time were enrolled. We retrospectively performed a univariate analysis using the patients' medical records to identify factors affecting the therapeutic effect of LCAP. Body mass index exceeding 18.5 kg/m(2) was found to influence the therapeutic effect of LCAP. Male sex was correlated with a rapid response to LCAP treatment and the maintenance of remission. UC patients experiencing their first attack or had an elevated C-reactive protein level prior to LCAP therapy exhibited a relatively long remission period. In the "after LCAP therapy" group, a low Rachmilewitz endoscopic score, low erythrocyte sedimentation rate, or high white blood cell count was associated with a long remission period. Our results suggest that LCAP should be performed for the treatment of early-onset UC. LCAP can be expected to induce a long remission period, enabling mucosal healing, although the factors that affected the remission period did not influence the therapeutic effect and responsiveness.

Microarray analyses of peripheral whole blood cells from ulcerative colitis patients: effects of leukocytapheresis

Complementary DNA microarray technology allows the simultaneous analysis of the expression of hundreds to thousands of genes. We applied this technique to clarify the molecular mechanisms underlying the therapeutic effects of leukocytapheresis (LCAP) therapy in patients with ulcerative colitis (UC). A 776-gene microarray analysis was performed using whole blood cells from six normal subjects and six patients with active UC who had undergone filtration LCAP. Widespread gene upregulation was observed in patients with UC, compared with normal subjects. After LCAP, genes with proinflammatory actions, such as CD97, CD74, human leukocyte antigen-DRβ1 and -DP light chain, were downregulated, while genes responsible for antimicrobial actions, such as neutrophil gelatinase-associated lipocalin, and acute phase reactions, such as haptoglobin α1S and α1-acid glycoprotein, were upregulated. In conclusion, we identified several genes expressed in the whole blood cells of UC patients as well as the transcriptional events following LCAP. Following LCAP, the gene profile shifted toward a pattern indicating disease improvement. These results suggest a basis for the molecular mechanisms leading to the therapeutic effects of LCAP and also indicate new therapeutic targets, providing important prognostic information.

Therapeutic leukocytapheresis in inflammatory bowel disease: clinical efficacy and mechanisms of action

Intense infiltration of the intestinal mucosa by activated leukocytes is a hallmark of inflammatory bowel disease (IBD). Therefore, removal of circulating leukocytes may be an attractive approach for treating IBD. Leukocytapheresis with Cellsorba, a column of polyethylenephtarate fibers that captures monocytes, granulocytes and lymphocytes, has been used to treat IBD, particularly ulcerative colitis, in Japan and Europe. This article reviews the clinical efficacy and safety data and the mechanisms of action of leukocytapheresis in IBD. Although the majority of clinical studies enrolled only small numbers of patients and had open-labeled designs, leukocytapheresis showed clinical efficacy with an excellent safety profile. Leukocytapheresis depletes granulocytes, monocytes, lymphocytes and platelets, alters cell population profiles, modulates cytokine production, and induces bone marrow-derived cells. In conclusion, leukocytapheresis exerts anti-inflammatory and tissue-repairing effects on the intestinal mucosa in IBD. Further studies are needed to explain the exact mechanism of action and to determine the true efficacy of this approach.

Mobilization of bone marrow cells by leukocytapheresis in patients with ulcerative colitis

While several trials have suggested that leukocytapheresis by filtration can benefit patients with active ulcerative colitis (UC), mechanisms underlying these benefits are largely unknown. We studied how leukocytapheresis mobilizes bone marrow cells into the peripheral circulation in patients with active UC. Leukocytapheresis transiently reduced peripheral leukocytes, followed by an overshoot increase with emergence of immature leukocytes. The numbers of colonies and CD34(+) cells were comparable between UC patients and normal controls. Shortly after leukocytapheresis, the numbers of both colonies and CD34(+) cells increased significantly in UC patients (P < 0.0001 and P = 0.0372, respectively). This was not associated with changes in the concentration of circulating cytokines or epinephrine. These results indicate that leukocytapheresis mobilizes bone marrow cells into the circulation. This cell replacement may partly explain the therapeutic benefit in UC. The functional role of the mobilized bone marrow cells in affected intestine remains to be characterized.

Microarray analysis of leukocytapheresis-induced changes in gene expression patterns of peripheral blood mononuclear cells in patients with ulcerative colitis

To elucidate the molecular mechanisms involved in the therapeutic effects of leukocytapheresis (LCAP), we performed microarray analysis for gene expression patterns in peripheral blood mononuclear cells (PBMCs) before and after LCAP therapy in patients with ulcerative colitis (UC). Four patients with UC were enrolled. PBMCs were isolated from peripheral venous blood obtained within 5 min before and after the first session of LCAP therapy. Cells were stimulated with IL-1beta for 12 h, and gene expression patterns were analyzed by an IntelliGene HS Human Expression Chip. The LCAP session reduced various genes, such as proinflammatory cytokines (IL-1alpha, IL-1beta, IL-6, IL-8, TNF-alpha, and IFN-gamma), cytokine receptors (IL-1R and IL-2Ralpha), chemokines, chemokine receptors, and intracellular signal transduction molecules. Genes which had increased after the LCAP session included those regulating anti-inflammatory cytokines and proteins (TGF-beta1 and IL-R antagonist), receptors for anti-inflammatory cytokines (IL-10R and IL-4R), growth factor receptors (IGF-R1, R2) and antioxidant proteins. Total changes in gene expression patterns after LCAP session were a combination of a decrease in pro-inflammatory genes and an enhancement of anti-inflammatory genes. These changes may explain some parts of the mechanisms by which LCAP improves clinical symptoms of UC patients.

Selective leukocyte apheresis for the treatment of inflammatory bowel disease

The etiology of inflammatory bowel disease (IBD) is not completely understood, thus current therapies have been empirical and directed at treating symptoms rather than addressing the cause. In IBD, the overexpression of proinflammatory cytokines, such as tumor necrosis factor-alpha, interleukin-1beta, interleukin-6, leads to a persistent intestinal inflammatory response that damages the intestinal mucosa. Recent advances in pharmacologic therapies that target specific cytokines, chemokines, and adhesion molecules have proved successful in alleviating symptoms for some patients. There are 2 selective adsorption apheresis devices that remove leukocytes from whole blood, which are currently available in Japan and Europe-the Cellsorba leukocytapheresis column and the Adacolumn adsorptive extracorporeal granulocyte/monocyte apheresis device. The purported mechanisms of action of these devices have been extensively reviewed and are believed to exert an immunomodulatory and/or anti-inflammatory effect on patients with systemic inflammatory disease. The clinical trials presented here indicate that selective leukocyte apheresis effectively removes activated granulocytes and monocytes/macrophages from peripheral blood while maintaining an excellent safety profile. Despite these findings, large controlled trials of selective leukocyte apheresis in the treatment of IBD are needed to determine the true efficacy of this approach.

Leukocytapheresis (LCAP) in the management of chronic active ulcerative colitis--results of a randomized pilot trial

Recent studies suggest that leukocytapheresis with Cellsorba is a valuable therapy for ulcerative colitis after failure of conventional treatment. In this study the potential of leukocytapheresis to induce remission in refractory chronic colitis under the conditions of European treatment guidelines was investigated. The therapeutic benefit of leukocytapheresis in the maintenance of remission was additionally elucidated. Twenty patients were treated weekly for 5 weeks. A significant decrease in the activity index was observed. Fourteen patients achieved clinical remission, and mucosal healing was observed endoscopically in six patients. After randomization these 14 patients in remission entered a second period of either monthly leukocytapheresis or no further treatment. In both groups steroids were tapered down. After 6 months, only one patient in the control group remained in remission, in contrast to five of eight patients in the leukocytapheresis group. In conclusion, leukocytapheresis may offer a therapeutic option in the induction and the maintenance of remission in chronic active ulcerative colitis.

Extracorporeal leukocyte removal therapy for patients with ulcerative colitis

BACKGROUND

The purpose of the present paper was to investigate efficacy of leukocytapheresis (LCAP) or granulocytapheresis (GCAP) in pediatric patients with ulcerative colitis (UC), including reduction of the total dose and side-effects of corticosteroids.

METHODS

Courses of five Japanese adolescents with UC were analyzed. Four patients had recurrent UC with repeated remissions and exacerbations despite therapy including 5-aminosalicylic acid in combination with a corticosteroid. The other patient had a first attack. Effectiveness of adding LCAP or GCAP was assessed with regard to short-term changes in clinical activity, complications, and longer-term outcome.

RESULTS

Clinical improvement was attained in three patients, while the other two did not improve and underwent colectomy. One of the two patients had moderately severe complications from LCAP and showed increased clinical activity during LCAP. The other, who began therapy with LCAP alone, had moderate improvement only after addition of a corticosteroid.

CONCLUSION

Additional studies are needed to determine optimum timing of LCAP or GCAP and initiation of remission-maintenance therapy.

Improvements in Treatment Strategies for Patients With Antineutrophil Cytoplasmic Antibody-associated Rapidly Progressive Glomerulonephritis

The course of rapidly progressive glomerulonephritis (RPGN) caused by antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis is often life-threatening, especially in the elderly when pulmonary involvement and/or severely impaired renal function are present. Corticosteroids and cyclophosphamide are the first-line treatment, but ironically infection, not vascular events such as hemorrhage, caused by the vasculitis itself, is the most common cause of death of RPGN patients. Several new treatment strategies, such as leukocytapheresis (LCAP) and intravenous immunoglobulin (IVIg), have become available during the past decade and these treatments have made it possible to treat high-risk RPGN patients without inducing serious immunosuppressive states. In the present paper we review recent clinical trials of LCAP and IVIg therapy in patients with pauci-immune/ANCA-associated RPGN, and show improved clinical outcomes after using these new treatment strategies in our institution.

Leukocyte removal therapy for ulcerative colitis does not affect postoperative complications

BACKGROUND

We investigated the incidence of postoperative complications in patients treated with or without preoperative leukocyte removal therapy (LRT).

METHODS

The case notes of 387 patients with ulcerative colitis (UC) who underwent surgical intervention were retrospectively reviewed. One hundred nine patients were treated with LRT within 8 weeks before surgery (LRT group), and 278 had not received LRT since at least 8 weeks before surgery (without LRT group). We reviewed the postoperative complications according to type of initial operation.

RESULTS

Of the patients who underwent an ileal J-pouch anal anastomosis (IPAA) without an ileostomy, 3 (6.5%) in the LRT group developed pouch-related complications (PRC), while 11 (7.5%) in the without LRT group developed PRC. The overall postoperative complication rates were 28.3% in the LRT group and 21.8% in the without LRT group. For patients who underwent an IPAA with an ileostomy, the overall rates of postoperative complications were 39.1% in the LRT group and 31.8% in the without LRT group. Among those undergoing a total colectomy, 33.3% in the LRT group and 18.2% in the without LRT group had postoperative complications. No statistically significant differences were demonstrated between the two groups with respect to postoperative complications.

CONCLUSIONS

Our results suggest that preoperative LRT does not influence the rate of postoperative complications in UC patients.

Modulation of platelet aggregation responses by leukocytapheresis therapy in patients with active ulcerative colitis

BACKGROUND

Recent studies suggest that platelet activation plays an important role in the pathophysiology of inflammatory bowel disease. In this study, we evaluated the effects of leukocytapheresis (LCAP) on platelet functions in patients with ulcerative colitis (UC).

METHODS

Thirteen patients with active UC (five women and eight men) were treated with LCAP therapy. Platelet-rich plasma (PRP) was prepared, and platelet aggregation in response to agonist solution (epinephrine, collagen, and ADP) was measured with a platelet aggregometer. Platelet-derived microparticle (PDMP) plasma levels were determined by enzyme-linked immunosorbent assay.

RESULTS

Nine patients responded to LCAP therapy, but no clinical responses were observed in four patients. The aggregation response to 0.1 microg/ml epinephrine was enhanced in all patients. In all responders, enhanced epinephrine aggregation was normalized after the LCAP session. However, in the four nonresponders, enhanced epinephrine aggregation was maintained after the LCAP session. In responders, the mean maximum aggregation induced by 0.1 microg/ml epinephrine was 76.8 +/- 5.0% before and 15.4 +/- 3.8% after LCAP, respectively (P < 0.05). Increased aggregation responses to both 0.2 microg/ml collagen and 1.0 microM ADP were observed, and LCAP also normalized these enhanced responses. LCAP significantly reduced circulating PDMP levels (56.8 +/- 28.3 U/ml before and 46.3 +/- 30.4 U/ml after LCAP, P < 0.05).

CONCLUSIONS

LCAP reduced enhanced platelet aggregation responses in active UC patients. Because platelets play an important role in inflammatory and immune responses, therapeutic effects of LCAP may be partially mediated by reduction of increased platelet aggregation activities.

Leukocytapheresis for Ulcerative Colitis: A Comparative Study of Anticoagulant (Nafamostat Mesilate vs. Dalteparin Sodium) for Reducing Clinical Complications

Leukocytapheresis (LCAP) is a therapeutic strategy for extra corporeal immunomodulation that has been used to treat several immunological disorders, including ulcerative colitis (UC), with encouraging results, inducing remission in steroid-resistant patients. However, we have experienced some complications during or after LCAP therapy. Common adverse effects include fever, chills, nausea, vomiting, and hypotension. One of the reasons for these adverse effects might be the use of nafamostat mesilate (NM) as an anticoagulant. In the present study, 75 patients with UC were divided into two groups, an NM group and a dalteparin sodium (DS) group. The clinical efficacy of these treatments, improvement after treatment, changes in leukocyte differential count, and adverse effects after LCAP therapy were then compared. The clinical efficacy, improvement after treatment, and changes in leukocyte classification were not significantly different between the two groups, while some adverse effects were observed in the NM group but not in the DS group. In conclusion, LCAP therapy is a useful therapy for patients with moderate to severe UC who fail to respond to glucocorticoid therapy, however, a safe anticoagulant should be used to avoid its related adverse effects.

Diminished cytokine signalling against bacterial components in mononuclear leucocytes from ulcerative colitis patients after leukocytapheresis

Infiltration by circulating inflammatory cells is a prominent local inflammatory feature of ulcerative colitis (UC). Several trials have suggested that leukocytapheresis by filtration can benefit patients with active UC. We investigated how this therapy might modulate the inflammatory response. Patients with active UC who were beginning repeated filtration leukocytapheresis were studied. Mononuclear cell preparations were obtained from blood before and after the first treatment, and expression of cytokine signalling components and the cell-proliferative response were analysed in vitro. Leukocytapheresis reduced lipopolysaccharide-induced production of proinflammatory cytokines (interleukin-1, -6, -8 and tumour necrosis factor-alpha, P < 0.05 for all) and activation of intracellular signalling components (nuclear factor-kappaB, mitogen-activated protein kinases, and signal transducer and activator of transcription-3), as well as surface expression of toll-like receptor-4 (P < 0.05) in mononuclear cells. The therapy also reduced the cell-proliferative response by mononuclear cells stimulated with sonicated bacterial preparations from autologous intestine (P < 0.05). These results indicate that activated mononuclear cells in the peripheral blood of patients with active UC are removed by leukocytapheresis and replaced by cells with a lower activation status. This replacement may partly explain the therapeutic benefit.

Leukocytapheresis Therapy Modulates Circulating T cell Subsets in Patients With Ulcerative Colitis

The aim of this study was to elucidate the molecular mechanisms responsible for the therapeutic effects of leukocytapheresis (LCAP). We investigated the alterations in circulating T cell subsets after LCAP therapy in ulcerative colitis (UC) patients. Eighteen patients with UC were enrolled. Fourteen patients were responders, and four patients were non-responders. Peripheral venous blood was obtained within 5 min before and 5 min after LCAP therapy. Flow cytometric analysis for T cell markers and intracellular interferon (IFN)-gamma (Th1) and interleukin (IL)-4 (Th2) was then performed. The average numbers of lymphocytes, T and B cells were significantly decreased after LCAP therapy, respectively (P < 0.01). The numbers of CD4+ and CD8+ T cells were also significantly decreased, respectively (P < 0.01), but the CD4+/CD8+ ratio was not changed. The number of CD45RO+ CD4+ memory T cells was significantly decreased. The number of CD25+ CD4+ T cells tended to decrease after LCAP therapy (not significant). However, the ratio of CD25+ CD4+-cells/CD25- CD4+-cells was significantly increased (P < 0.05). The number of IFN-gamma-positive (Th1) cells was significantly decreased after LCAP therapy, but there was no significant change in the number of IL-4-positive (Th2) cells. The Th1/Th2 ratio was significantly decreased after LCAP therapy. Some of the immuno-suppressive effects of LCAP therapy may be associated with a modulation of circulating T cell subsets.

Detection of specific IgE antibodies to nafamostat mesilate as an indication of possible adverse effects of leukocytapheresis using nafamostat mesilate as anticoagulant

The aim was to determine whether adverse effects of leukocytapheresis (LCAP) are related to nafamostat mesilate (NM) as an anticoagulant. Anti-NM IgE were detected in inflammatory bowel disease (IBD) patients who were administrated LCAP in our institute. Forty-nine patients (ulcerative colitis (UC)/Crohn's disease (CD): 30/19) were evaluated. Anti-NM IgE was measured by the ELISA method. Total IgE level and eosinophil count was tested concurrently. We retrospectively checked the presence of allergic symptoms and medications used concurrently with LCAP. Anti-NM IgE were present in six symptomatic patients (6/49; 12.2%) whose adverse effects were highly suspected to be from NM. However, 21 patients showed anti NM IgE-negative, in spite of the fact that their adverse effects were also highly suspected to be from NM. Through the detection of anti-NM IgE alone we could not estimate the relevance of NM as an anticoagulant to the adverse effects of LCAP.

Clinical-scale generation of dendritic cells in a closed system

Immunotherapy of malignant diseases based on dendritic cells (DCs) pulsed with tumor antigens is a promising approach. Therefore, there is a demand for large-scale, clinical-grade ex vivo generation of DCs. Here, a procedure is presented that combines monocyte selection and tissue culture in closed systems under current good manufacturing practice conditions. Leukocytes from three patients with urologic cancers were collected by leukapheresis and subjected to immunomagnetic enrichment. From leukapheresis products containing 1.6 +/- 0.2 x 1010 (mean +/- SEM) leukocytes with a frequency of CD14+ monocytes of 18.7 +/- 2.3%, monocytes were enriched to 94.3 +/- 2.2%. CD14+ cell recovery was 67.0 +/- 4.7%. After 6 days of culture in Teflon bags in X-Vivo 15 medium supplemented with autologous plasma, GM-CSF, and IL-4, cells showed an immature DC phenotype and efficient antigen uptake. Following an additional 3 days of culture in the presence of GM-CSF, IL-4, IL-1beta, IL-6, TNFalpha, and PGE(2), cells (82.0 +/- 5.8% CD83+) displayed a mature DC morphology and phenotype, including expression of CD11b, CD11c, CD18, CD25, CD40, CD54, CD58, CD80, CD86, HLA class I, and HLA-DR as well as expression of CCR7 but not CCR5. The mature DC phenotype remained stable for at least 5 days in the absence of cytokines. Yield of DC was 14.0 +/- 4.7% and viability was 91.9 +/- 3.5%. Mature DCs effectively clustered with naive T cells and potently induced allogeneic T-cell proliferation and IL-2 and IFNgamma but not IL-4 production. Thus, this procedure allows large-scale generation of stably mature, Th1 responses inducing DCs under cGMP conditions in a closed system from cancer patients and is therefore well suited for immunotherapy.

A review of leukofiltration therapy for decreasing the morbidity associated with cardiopulmonary bypass and acute inflammatory bowel disease

Complications of cardiopulmonary bypass (CPB) and acute inflammatory bowel disease (IBD) are associated with increased morbidity and cost. During reperfusion post-CPB, activated neutrophils adhere to microvascular endothelial cells mediated by cell adhesion molecules (CAMs) and cytokines/chemokines with subsequent myocardial damage caused by activated neutrophil-derived oxidants and enzymes. Leukofiltration was shown to reduce myocardial reperfusion injury and improve gas exchange as suggested by improvements in surrogate markers of inflammation and clinical end points. In acute IBD, characterized by rectal bleeding and protracted hospital stays, circulating neutrophils emigrate to the inflamed colon and adhere to microvascular endothelial cells by CAMs. Multiple treatments with leukofiltration in IBD were shown to induce long-term remission of acute IBD. Hence, leukofiltration may reduce reperfusion injury and rectal bleeding in CPB and IBD, respectively, and therefore decrease the morbidity and cost associated with these diseases.

Leukapheresis reduces early mortality in patients with acute myeloid leukemia with high white cell counts but does not improve long- term survival

PURPOSE

Current published data on therapeutic leukapheresis in hyperleucocytic AML does not define the impact on survival from this procedure. Between 1992 and 1999 we saw 146 patients with newly-diagnosed AML (APL excluded) and an initial WBC count > 50 x 10(9)/L of whom 71 underwent leukapheresis at the discretion of their treating doctors. We compared outcome (early mortality, CR, and overall survival) rates in the patients who were and were not pheresed. After accounting for covariates relevant to these outcomes, including age, performance status, and cytogenetics, there was evidence (p = .006) that pheresis reduced 2-week mortality rate and a suggestion (p = .06) that this resulted in a higher CR rate. However there was no evidence that pheresis lengthened longer-term or overall survival; if anything the suggestion was the converse (p = .06). These data may reflect the fact that the patients chosen to have pheresis were prognostically unfavorable as defined by variables that were not captured in our data set, since the alternative explanation i.e. that pheresis per se shortens overall survival seems less likely. Whether the above justifies the use of pheresis in the absence of evidence from a randomized trial is doubtful, but it seems likely that any long-term benefit to be derived from this procedure must await further advances in anti-leukemia therapy.

Fulminant Ulcerative Colitis

Fulminant ulcerative colitis necessitates immediate hospitalization. Supportive therapy such as aggressive rehydration, restriction of oral intake, and consideration of parenteral nutrition should be initiated. High-dose intravenous steroids should be started in almost all cases. Antibiotics and cyclosporine should be considered, especially in disease refractory to steroid therapy. Indications for surgery should always be kept in mind, and early involvement of the surgical team is always encouraged. Avoidance of life-threatening complications such as toxic megacolon, hemorrhage, and perforation is the goal of any treatment for fulminant ulcerative colitis.