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The New England Journal of Medicine | 2010

Rituximab versus Cyclophosphamide for ANCA-Associated Vasculitis

John H. Stone; Peter A. Merkel; Robert Spiera; Philip Seo; Carol A. Langford; Gary S. Hoffman; Cees G. M. Kallenberg; E. William St. Clair; Anthony M. Turkiewicz; Nadia K. Tchao; Lisa Webber; Linna Ding; Lourdes P. Sejismundo; Kathleen Mieras; David Weitzenkamp; David Ikle; Vicki Seyfert-Margolis; Mark Mueller; Paul Brunetta; Nancy B. Allen; Fernando C. Fervenza; Duvuru Geetha; Karina A. Keogh; Eugene Y. Kissin; Paul A. Monach; Tobias Peikert; Coen A. Stegeman; Steven R. Ytterberg; Ulrich Specks

BACKGROUND Cyclophosphamide and glucocorticoids have been the cornerstone of remission-induction therapy for severe antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis for 40 years. Uncontrolled studies suggest that rituximab is effective and may be safer than a cyclophosphamide-based regimen. METHODS We conducted a multicenter, randomized, double-blind, double-dummy, noninferiority trial of rituximab (375 mg per square meter of body-surface area per week for 4 weeks) as compared with cyclophosphamide (2 mg per kilogram of body weight per day) for remission induction. Glucocorticoids were tapered off; the primary end point was remission of disease without the use of prednisone at 6 months. RESULTS Nine centers enrolled 197 ANCA-positive patients with either Wegeners granulomatosis or microscopic polyangiitis. Baseline disease activity, organ involvement, and the proportion of patients with relapsing disease were similar in the two treatment groups. Sixty-three patients in the rituximab group (64%) reached the primary end point, as compared with 52 patients in the control group (53%), a result that met the criterion for noninferiority (P<0.001). The rituximab-based regimen was more efficacious than the cyclophosphamide-based regimen for inducing remission of relapsing disease; 34 of 51 patients in the rituximab group (67%) as compared with 21 of 50 patients in the control group (42%) reached the primary end point (P=0.01). Rituximab was also as effective as cyclophosphamide in the treatment of patients with major renal disease or alveolar hemorrhage. There were no significant differences between the treatment groups with respect to rates of adverse events. CONCLUSIONS Rituximab therapy was not inferior to daily cyclophosphamide treatment for induction of remission in severe ANCA-associated vasculitis and may be superior in relapsing disease. (Funded by the National Institutes of Allergy and Infectious Diseases, Genentech, and Biogen; ClinicalTrials.gov number, NCT00104299.)


The New England Journal of Medicine | 2013

Efficacy of Remission-Induction Regimens for ANCA-Associated Vasculitis

Ulrich Specks; Peter A. Merkel; Philip Seo; Robert Spiera; Carol A. Langford; Gary S. Hoffman; Cees G. M. Kallenberg; E. William St. Clair; Barri J. Fessler; Linna Ding; L. Viviano; Nadia K. Tchao; Deborah Phippard; Adam Asare; Noha Lim; David Ikle; Brett Jepson; Paul Brunetta; Nancy B. Allen; Fernando C. Fervenza; Duvuru Geetha; Karina A. Keogh; Eugene Y. Kissin; Paul A. Monach; Tobias Peikert; Coen A. Stegeman; Steven R. Ytterberg; Mark Mueller; Lourdes P. Sejismundo; Kathleen Mieras

BACKGROUND The 18-month efficacy of a single course of rituximab as compared with conventional immunosuppression with cyclophosphamide followed by azathioprine in patients with severe (organ-threatening) antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis is unknown. METHODS In a multicenter, randomized, double-blind, double-dummy, noninferiority trial, we compared rituximab (375 mg per square meter of body-surface area administered once a week for 4 weeks) followed by placebo with cyclophosphamide administered for 3 to 6 months followed by azathioprine for 12 to 15 months. The primary outcome measure was complete remission of disease by 6 months, with the remission maintained through 18 months. RESULTS A total of 197 patients were enrolled. As reported previously, 64% of the patients in the rituximab group, as compared with 53% of the patients in the cyclophosphamide-azathioprine group, had a complete remission by 6 months. At 12 and 18 months, 48% and 39%, respectively, of the patients in the rituximab group had maintained the complete remissions, as compared with 39% and 33%, respectively, in the comparison group. Rituximab met the prespecified criteria for noninferiority (P<0.001, with a noninferiority margin of 20%). There was no significant difference between the groups in any efficacy measure, including the duration of complete remission and the frequency or severity of relapses. Among the 101 patients who had relapsing disease at baseline, rituximab was superior to conventional immunosuppression at 6 months (P=0.01) and at 12 months (P=0.009) but not at 18 months (P=0.06), at which time most patients in the rituximab group had reconstituted B cells. There was no significant between-group difference in adverse events. CONCLUSIONS In patients with severe ANCA-associated vasculitis, a single course of rituximab was as effective as continuous conventional immunosuppressive therapy for the induction and maintenance of remissions over the course of 18 months. (Funded by the National Institute of Allergy and Infectious Diseases and others; RAVE ClinicalTrials.gov number, NCT00104299.)


Annals of Internal Medicine | 2007

Antiproteinase 3 Antineutrophil Cytoplasmic Antibodies and Disease Activity in Wegener Granulomatosis

Javier D. Finkielman; Peter A. Merkel; Darrell R. Schroeder; Gary S. Hoffman; Robert Spiera; E. William St. Clair; John C. Davis; W. Joseph McCune; Andrea Lears; Steven R. Ytterberg; Amber M. Hummel; Margaret A. Viss; Tobias Peikert; John H. Stone; Ulrich Specks

Context Most patients with Wegener granulomatosis have antineutrophil cytoplasmic antibodies (ANCA). The role of ANCA testing in monitoring response to treatment is controversial. Contribution Using data from a large treatment trial, the authors found little association between disease activity and ANCA levels. Decreases in ANCA levels were not associated with remission, and increases were not associated with relapse. Caution Because follow-up duration differed by patient, standard measures of ANCA accuracy, such as sensitivity and specificity for detecting remission and relapse, could not be calculated. Implication Serial ANCA testing should not be used to monitor disease activity or to guide decisions about immunosuppressive treatment in patients with Wegener granulomatosis. The Editors Wegener granulomatosis is characterized by necrotizing granulomatous inflammation and vasculitis, most commonly affecting the respiratory tract and kidneys (1, 2). Remission can be induced in most patients by using glucocorticoids with cyclophosphamide or methotrexate (17), but most patients have relapse when immunosuppression is reduced or withdrawn (1, 2, 6, 8). Consequently, patients experience substantial illness and damage from both the disease and treatment toxicity (1, 9). Accurate assessment of disease activity and prediction of relapse remain the biggest challenges in management of Wegener granulomatosis (10). Most patients with Wegener granulomatosis have antineutrophil cytoplasmic antibodies (ANCA), which produce a cytoplasmic immunofluorescence pattern on ethanol-fixed neutrophils and react with the neutrophil serine protease proteinase 3 (PR3) (1115). Proteinase 3 is synthesized as a proenzyme (pro-PR3) containing an amino-terminal activation dipeptide that preserves PR3 in an inactive state (16). Subsequent cleavage of this dipeptide allows PR3 to assume its active enzyme conformation (mature-PR3) (16). The diagnostic value of ANCA is well established (17, 18); however, the role of serial ANCA measurements during follow-up and their utility in guiding treatment remain controversial (10, 19, 20). A recent study indicated that in individual patients with Wegener granulomatosis, ANCA against pro-PR3 had a stronger correlation with disease activity than did ANCA against mature-PR3 (21). Therefore, we sought to determine whether pro-PR3ANCA levels correlate more strongly with disease activity than do mature-PR3ANCA levels, whether a decrease in pro- or mature-PR3ANCA levels during remission-induction therapy is associated with a shorter time to sustained remission, and whether an increase in pro- or mature-PR3ANCA levels is associated with relapse. Methods This prospective study was done in the context of the WGET (Wegener Granulomatosis Etanercept Trial) (6, 22, 23), a randomized, placebo-controlled trial that evaluated etanercept for maintenance of remission in 180 patients with Wegener granulomatosis at 8 centers across the United States (Appendix 1). All patients met at least 2 of the 5 modified American College of Rheumatology criteria for classification of Wegener granulomatosis and had active disease within 28 days before enrollment and a Birmingham Vasculitis Activity Score for Wegener granulomatosis (BVAS/WG) of at least 3 (22, 24). Follow-up evaluations were done at baseline, after 6 and 12 weeks, and then every 3 months until the end of the trial. Two additional evaluations took place at 3 and 6 months after the end of the trial. During each visit, disease activity was measured by using the BVAS/WG, and serum samples were obtained, frozen, and stored at 80 C. Treatment Patients were treated in a protocol-defined manner with etanercept or placebo in addition to standard therapies. Patients with severe Wegener granulomatosis (life- or organ-threatening disease) received cyclophosphamide and glucocorticoids at enrollment (22, 24). Those with limited (that is, nonsevere) Wegener granulomatosis received methotrexate and glucocorticoids. Medication dosages were tapered according to protocol once disease activity was controlled (6, 22). Assessment of Disease Activity and Definitions of Sustained Remission and Relapse Disease activity was measured by using the BVAS/WG (24). This index considers all manifestations of active disease during the 28 days preceding the date of assessment. A BVAS/WG of 1 or greater is considered active disease, and a BVAS/WG of 0 indicates remission (24). Our analyses focused on first sustained remission and first relapse. Sustained remission was defined as a BVAS/WG of 0 for at least 6 months (6, 22). The PR3-ANCA level at the visit in the middle of this period was considered the PR3-ANCA level at sustained remission. Disease relapse was defined as an increase of at least 1 point in the BVAS/WG in patients who had sustained remission. ANCA Detection Methods A standard immunofluorescence assay and direct enzyme-linked immunosorbent assays (ELISAs) for PR3-ANCA and ANCA against myeloperoxidase were done as described elsewhere (25). Capture ELISA was used to measure PR3-ANCA (2527); levels are expressed as net absorbance, and a level of 0.10 or greater is considered positive (26, 27). The intra-assay and interassay coefficients of variation are 9% and 31%, respectively, for pro-PR3 capture ELISA, and 6% and 28%, respectively, for mature-PR3 capture ELISA. All baseline serum samples were screened at first thaw by using all methods. Patients whose baseline samples tested positive for perinuclear-staining ANCA or ANCA against myeloperoxidase (n= 24) were excluded from further analyses because of substantial differences in disease phenotype between patients positive for ANCA against myeloperoxidase and those positive for PR3-ANCA. In addition, the number of patients who were positive for ANCA against myeloperoxidase was too small for meaningful longitudinal analysis (5, 28, 29). Subsequently, all serum samples were tested for mature- and pro-PR3ANCA in parallel by using capture ELISA at first thaw (except for the baseline samples, which were retested at second thaw). To minimize variability, all serum samples from an individual patient were run at once in the same plate and the same lots of all reagents were used for all assays. Laboratory personnel were blinded to the clinical data. Increase and Decrease of PR3-ANCA Levels We defined an increase in PR3-ANCA levels a priori as an increase of at least 100% in the net absorbance over 6 months. An absolute increase of at least 0.4 was also required to ensure that small elevations were above the intra-assay coefficient of variation. We classified a negative-to-positive conversion of PR3-ANCA status as an increase only if the absolute increase was at least 0.4. Because 6 months corresponded to 3 clinical visits (except for the initial 6 months after enrollment, when it corresponded to 4 clinical visits), we compared the PR3-ANCA levels at each visit with those from the previous 2 to determine whether the criteria for increase were fulfilled. We first looked for an increase in PR3-ANCA 9 months after enrollment (the fourth visit), because that was the first time that a patient could meet the definition of sustained remission. Thus, the PR3-ANCA level at the fourth visit was compared with the levels at the third and second visits after enrollment. No increase in PR3-ANCA before the fourth visit after enrollment was analyzed (Appendix Figure 1). Appendix Figure 1. Diagram of the initial 4 clinical visits. The fourth clinical visit was the first point at which a patient could meet the study definition of sustained remission (SR) (a Birmingham Vasculitis Activity Score for Wegener granulomatosis [BVAS/WG] of 0 for 6 months) and was the first time we looked for an increase in proteinase 3 (PR3) antineutrophil cytoplasmic antibody (ANCA) levels. We compared the net absorbance of PR3-ANCA at this visit with that of the previous 2 visits or the previous 6 months (curved lines). The same comparison was done at every subsequent visit. We defined a decrease in PR3-ANCA levels during the initial 6 months of follow-up as a decline of at least 50% in the net absorbance with an absolute decrease of at least 0.4; for values between 0.1 and 0.4, the capture ELISA needed to yield negative results. Statistical Analysis Descriptive data are summarized as mean (SD), median (interquartile range), or percentages. Groups were compared by using the t test (or the rank-sum test) or the chi-square test (or Fisher exact test), with 95% CIs calculated as appropriate. A P value less than 0.05 was considered statistically significant. We performed unadjusted and adjusted analyses. The adjusting variables were age, sex, disease severity (severe vs. limited Wegener granulomatosis), treatment group (etanercept vs. placebo), disease duration, baseline BVAS/WG, and clinical center (see Appendix 2 for additional details). PR3-ANCA Levels and Disease Activity The cross-sectional and longitudinal associations between the BVAS/WG and the levels of mature- and pro-PR3ANCA were estimated by using random-effect models. We constructed the models with BVAS/WG as the dependent variable and included a random effect for each patient (random intercept) and 2 terms for PR3-ANCA levelsone term for the value of PR3-ANCA level at baseline and the other for the change in PR3-ANCA level from baseline to time t. To assess the magnitude of the association between PR3-ANCA levels and the BVAS/WG, we estimated the relative reduction in the residual variance by comparing the residual variance of the model that included a random effect for each patient and 2 terms for PR3-ANCA levels with the residual variance of a model that only included the random effect for each patient. These analyses included only observations in which both BVAS/WG and PR3-ANCA level were available (9% of the observations had missing PR3-ANCA information). For patients who achieved sustained remission, the mature- and pro-PR3ANCA level


Arthritis & Rheumatism | 2012

Rituximab for remission induction and maintenance in refractory granulomatosis with polyangiitis (Wegener's): Ten‐year experience at a single center

Rodrigo Cartin-Ceba; Jason M. Golbin; Karina A. Keogh; Tobias Peikert; Marta Sánchez-Menéndez; Steven R. Ytterberg; Fernando C. Fervenza; Ulrich Specks

OBJECTIVE This study was conducted to evaluate the efficacy and safety of repeated and prolonged B cell depletion with rituximab (RTX) for the maintenance of long-term remission in patients with chronic relapsing granulomatosis with polyangiitis (Wegeners) (GPA). METHODS We conducted a single-center observational study of all patients with chronic relapsing GPA treated with at least 2 courses of RTX between January 1, 2000 and May 31, 2010. Participants in the Rituximab in ANCA-Associated Vasculitis (RAVE) trial were excluded from this analysis. Data were abstracted from electronic medical records. RESULTS Fifty-three patients with refractory GPA (median age 46 years [interquartile range (IQR) 30-61 years]; 53% women) received at least 2 courses of RTX to treat GPA relapses or to maintain remission. All but 1 patient had antineutrophil cytoplasmic antibodies (ANCA) against proteinase 3 (PR3). These patients received a median of 4 courses of RTX (IQR 3-5); all had depletion of B cells, and the median time to return of B cells was 8.5 months (IQR 6-11 months). All observed relapses occurred after reconstitution of B cells and were accompanied or preceded by an increase in ANCA levels, except for the 1 ANCA-negative patient. Infusion-related adverse events occurred in 16 patients. During the period of B cell depletion, 30 infections requiring antimicrobial therapy were recorded. CONCLUSION RTX appeared to be effective and safe for the induction and maintenance of remission in patients with chronic relapsing GPA. Repeated depletion of B lymphocytes seems to be associated with a low risk of infections. Preemptive re-treatment decisions can be individualized based on serial B lymphocyte and PR3 ANCA monitoring. The use of RTX for the maintenance of long-term remission merits further formal investigation.


Journal of Thoracic Oncology | 2014

B7-H1 Expression in Malignant Pleural Mesothelioma is Associated with Sarcomatoid Histology and Poor Prognosis

Aaron S. Mansfield; Anja C. Roden; Tobias Peikert; Yuri Sheinin; Susan M. Harrington; Christopher J. Krco; Haidong Dong; Eugene D. Kwon

Introduction: B7 homolog 1 (B7-H1; aka programmed cell death 1 ligand 1) is a negative costimulatory molecule that is associated with poor prognosis in many tumor types. Given the poor prognosis and the limited treatments available for mesothelioma, we decided to examine B7-H1 expression and its association with survival in patients with mesothelioma. Methods: Expression of B7-H1 was determined in 106 patients using a mouse monoclonal antihuman B7-H1 (clone 5H1-A3) antibody with immunohistochemistry. Positive expression was defined as ≥5% positively stained cells. Clinicopathologic features and survival were compared between B7-H1-positive and B7-H1-negative groups. Results: Malignant mesotheliomas of 42 patients (40%) expressed B7-H1. Patients with B7-H1-postive tumors were less likely to be offered or undergo therapeutic surgery (p = 0.03). All sarcomatoid mesotheliomas except one desmoplastic subtype expressed B7-H1. Survival was significantly decreased for patients whose tumors expressed B7-H1 (5 months median, 2–9.5 months interquartile range) compared with those whose tumors did not (14.5 months, 9.25–19 months; p < 0.0001). In a multivariate model, B7-H1 expression and sarcomatoid mesothelioma remained significantly associated with worse survival (risk ratio 1.71, 95% confidence interval 1.03–2.78 [p = 0.04] and risk ratio 2.18, 1.08–4.23 [p = 0.03], respectively). Conclusions: B7-H1 is expressed in a substantial proportion of malignant pleural mesotheliomas and is associated with poor survival. Almost all malignant pleural mesotheliomas with sarcomatoid differentiation expressed B7-H1. The expression of B7-H1 may have important therapeutic implications for the management of malignant pleural mesothelioma.


International Journal of Rheumatology | 2012

Spectrum of Disorders Associated with Elevated Serum IgG4 Levels Encountered in Clinical Practice.

Jay H. Ryu; Ryohei Horie; Hiroshi Sekiguchi; Tobias Peikert; Eunhee S. Yi

IgG4-related disease (IgG4-RD) is a recently described systemic fibroinflammatory disease associated with elevated circulating levels of IgG4 and manifests a wide spectrum of clinical presentations. Although serum IgG4 level has been described to be the most sensitive and specific laboratory test for the diagnosis of IgG4-RD, it is recognized that an elevated serum IgG4 level can be encountered in other diseases. In this study, we sought to identify the frequency of IgG4-RD and other disease associations in patients with elevated serum IgG4 levels seen in clinical practice. Among 3,300 patients who underwent IgG subclass testing over a 2-year period from January 2009 to December 2010, 158 (4.8%) had an elevated serum IgG4 level (>140 mg/dL). IgG4 subclass testing was performed for evaluation of suspected IgG4-RD or immunodeficiency. Twenty-nine patients (18.4%) had definite or possible IgG4-RD. Among those patients without IgG4-RD, a broad spectrum of biliary tract, pancreatic, liver, and lung diseases, as well as systemic vasculitis, was diagnosed. We conclude that patients with elevated serum IgG4 levels encountered in clinical practice manifest a wide array of disorders, and only a small minority of them has IgG4-RD.


Cancer Research | 2006

Melanoma Antigen A4 Is Expressed in Non–Small Cell Lung Cancers and Promotes Apoptosis

Tobias Peikert; Ulrich Specks; Carol Farver; Serpil C. Erzurum; Suzy Comhair

A variety of melanoma antigen A (MAGE-A) genes are commonly detected in non-small cell lung cancers. Their biological function is not well characterized but may involve the regulation of apoptosis and cell cycle progression. We hypothesized that MAGE-A4 is involved in the regulation of apoptosis. To investigate this, expression of MAGE-A was evaluated. MAGE-A4 was expressed in 48% of non-small cell lung carcinomas. Ninety percent of lung carcinomas expressing MAGE-A4 were classified as squamous cell carcinomas and 10% were adenocarcinomas. Tumor-free surrounding lung tissue was negative for MAGE-A4. A molecular clone of MAGE-A4 derived from human lung cancer was stably expressed in human embryonic kidney cells (293 cells) to evaluate effects on cell death. Overexpression of MAGE-A4 increased apoptosis as measured by the apoptotic index (P < 0.0001) and caspase-3 activity (P < 0.002). Exposure to 25 micromol/L etoposide, a chemotherapeutic agent, increased the apoptotic effect (P < 0.0001). Furthermore, we show that MAGE-A4 silencing using a small interfering RNA approach results in decreased caspase-3 activity in the squamous cell lung cancer cell line H1703 by 58% (P = 0.0027) and by 24% (P = 0.028) in 293/MAGE-A4 cells. These findings suggest that MAGE-A4 expression may promote tumor cell death, sensitize malignancies to apoptotic stimuli, such as chemotherapeutic agents, and therefore may represent a tumor suppressor protein.


Arthritis & Rheumatism | 2013

Clinical Outcomes of Remission Induction Therapy for Severe Antineutrophil Cytoplasmic Antibody–Associated Vasculitis

Eli M. Miloslavsky; Ulrich Specks; Peter A. Merkel; P. Seo; Robert Spiera; Carol A. Langford; Gary S. Hoffman; Cornelis Kallenberg; E W St Clair; Nadia K. Tchao; L. Viviano; Linna Ding; Lourdes P. Sejismundo; Kathleen Mieras; David Ikle; Brett Jepson; Mark Mueller; Paul Brunetta; Nancy B. Allen; Fernando C. Fervenza; Duvuru Geetha; Karina A. Keogh; Eugene Y. Kissin; Paul A. Monach; Tobias Peikert; Ca Stegeman; Steven R. Ytterberg; John H. Stone

OBJECTIVE To evaluate the reasons that complete remission is not achieved or maintained with original treatment in some patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) treated with rituximab (RTX) or with cyclophosphamide/azathioprine (CYC/AZA). METHODS The Rituximab in AAV trial was a randomized, double-blind, placebo-controlled trial comparing the rate of remission induction among patients treated with RTX (n = 99) and patients treated with CYC followed by AZA (n = 98). Glucocorticoids were tapered over a period of 5 months. The primary outcome measure was lack of disease activity without glucocorticoid treatment at 6 months. To determine the most important reason for failure to achieve the primary outcome, 7 hierarchical categories of reasons were defined retrospectively (uncontrolled disease, adverse event leading to therapy discontinuation, severe flare, limited flare, Birmingham Vasculitis Activity Score for Wegeners Granulomatosis >0, prednisone treatment at any dosage, and other). RESULTS Although remission (lack of disease activity) was achieved in 170 of the 197 patients (86%) in the first 6 months, the primary outcome measure was not achieved in 42%. There were 3 deaths. Twenty-four percent of the patients failed to achieve the primary end point due to active disease: 10 (5%) experienced uncontrolled disease in the first month and 37 (19%) experienced flares after initial improvement. In the majority of such patients, treatment with blinded crossover or according to best medical judgment led to disease control. Ninety-one percent of patients who had uncontrolled disease or experienced a severe flare had proteinase 3 (PR3)-ANCA. When patients with uncontrolled disease were excluded from analysis, those who were PR3-ANCA positive were found to experience fewer flares when treated with RTX compared to CYC/AZA (8 of 59 [14%] versus 20 of 62 [32%]; P = 0.02). Neither ANCA titers nor B cell counts predicted disease flare. CONCLUSION Current treatment regimens are largely successful in controlling AAV, but in approximately one-fourth of patients, active disease persists or recurs in the first 6 months despite treatment. PR3-ANCA positivity is a risk factor for recurrence or persistence of severe disease. ANCA titers and B cell detectability are poor predictors of both disease relapse and disease quiescence in the first 6 months.


Mayo Clinic Proceedings | 2005

Safety, Diagnostic Yield, and Therapeutic Implications of Flexible Bronchoscopy in Patients With Febrile Neutropenia and Pulmonary Infiltrates

Tobias Peikert; Sameer Rana; Eric S. Edell

OBJECTIVE To evaluate the safety, diagnostic yield, and therapeutic implications of flexible bronchoscopy with bronchoalveolar lavage (BAL) and transbronchial biopsy in patients with febrile neutropenia and pulmonary infiltrates. PATIENTS AND METHODS We retrospectively reviewed the medical records of all patients with neutropenic fever and pulmonary infiltrates evaluated by flexible bronchoscopy and BAL between January and December 2002 at the Mayo Clinic in Rochester, Minn. Appropriate demographic, clinical, microbiological, and histological data and procedure-related complications were summarized. Therapeutic decisions implemented based on Information obtained by bronchoscopy, and 28-day mortality were determined. RESULTS Thirty-five patients with febrile neutropenia and associated pulmonary infiltrates were identified. Flexible bronchoscopy, including 35 BALs and 9 transbronchial biopsies, was performed safely (3 complications). The diagnostic yield of BAL was 49%. Sputum analysis was underused (only 34%) but complementary to BAL. The combined diagnostic yield of BAL and sputum analysis was 63%. Transbronchial biopsy provided additional information to BAL and sputum analysis In only 1 patient and did not substantially increase the combined diagnostic yield. The most common diagnoses identified were fungal pneumonias (15/35 [43%]) and diffuse alveolar hemorrhage (5/35 [14%]). Bronchoscopic findings resulted in management changes in 51% of patients. The 28-day mortality rate was 26% and was highest in patients who required mechanical ventilatory assistance before bronchoscopy. CONCLUSION The favorable safety record, good diagnostic yield, and frequent therapeutic implications support the routine use of BAL for the evaluation of pulmonary inflitrates in neutropenic patients. Bronchoalveolar lavage should be combined with the analysis of several sputum specimens. Transbronchial biopsy did only change the management of 1 patient.


Medicine | 2011

Fibrosing Mediastinitis Clinical Presentation, Therapeutic Outcomes, and Adaptive Immune Response

Tobias Peikert; Thomas V. Colby; David E. Midthun; Peter C. Pairolero; Eric S. Edell; Darrell R. Schroeder; Ulrich Specks

Fibrosing mediastinitis (FM) is a rare disorder characterized by the invasive proliferation of fibrous tissue within the mediastinum. FM frequently results in the compression of vital mediastinal structures and has been associated with substantial morbidity and mortality. Its pathogenesis remains unknown. However, in North America most cases are thought to represent an immune-mediated hypersensitivity response to Histoplasma capsulatum infection. To characterize the clinical disease spectrum, natural disease progression, responses to therapy, and overall survival, we retrospectively analyzed all 80 consecutive patients with a diagnosis of FM evaluated at Mayo Clinic, Rochester, MN, from 1998 to 2007. Furthermore, we characterized the adaptive immune response in 15 representative patients by immunohistochemistry. The majority of patients presented with nonspecific respiratory symptoms due to the compression of mediastinal broncho-vascular structures. Chest radiographic imaging most frequently revealed localized, invasive, and frequently calcified right-sided mediastinal masses. Most patients had radiographic or serologic evidence of previous histoplasmosis. In contrast to earlier reports summarizing previously reported FM cases, the clinical course of our patients appeared to be more benign and less progressive. The overall survival was similar to that of age-matched controls. There were only 5 deaths, 2 of which were attributed to FM. These differences may reflect publication bias associated with the preferential reporting of more severely affected FM patients in the medical literature, as well as the more inclusive case definition used in our consecutive case series. Surgical and nonsurgical interventions effectively relieved symptoms caused by the compression of mediastinal vascular structures in these carefully selected patients. In contrast, antifungal and antiinflammatory agents appeared ineffective. Histologic examination and immunostaining revealed mixed inflammatory infiltrates consistent with a fibroinflammatory tissue response in these histoplasmosis-associated FM cases. The immune cell infiltrates included large numbers of CD20-positive B lymphocytes. As B lymphocytes may contribute to the pathogenesis of the disease, therapeutic B-cell depletion should be investigated as a therapeutic strategy for FM. Abbreviations: CT = computed tomography, FM = fibrosing mediastinitis, PET = positron emission tomography, SVC = superior vena cava.

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