Alveolar hemorrhage in anti-basement membrane antibody disease: a series of 28 cases

Anti-Glomerular Basement Membrane Disease: Recent Updates

Anti-glomerular basement membrane disease is a small-vessel vasculitis involving the kidneys (∼90%) and the lungs (∼60%). Antibodies against the glomerular basement membrane are directly pathogenic in anti-glomerular basement membrane disease; however, recent research has highlighted the critical role of T cells. Novel autoantigens within the glomerular basement membrane are also now recognized. Atypical forms of the disease are reported along with preceding triggers, such as immune checkpoint inhibitors, immunomodulatory drugs, and vaccines. Kidney outcomes in anti-glomerular basement membrane disease remain poor despite significant improvement in patient survival in the last 2 to 3 decades. Treatment typically relies on combined plasmapheresis with intensive immunosuppression. Dialysis dependency at presentation is a dominant predictor of kidney outcome. Histologically, a low (<10%) percentage of normal glomeruli, 100% crescents, together with dialysis dependency at presentation, is associated with poor kidney outcomes. In such cases, an individualized approach weighing the risks and benefits of treatment is recommended. There is a need for better ways to stop the toxic inflammatory activity associated with this disease. In this narrative review, we discuss recent updates on the pathogenesis and management of anti-glomerular basement membrane disease relevant to patients of all ages.

Pulmonary pathology in vasculitis

Pulmonary involvement is frequent in vasculitis, particularly in ANCA-associated small vessel vasculitis. Laboratory and radiological data alone are often sufficient to confirm the clinical hypothesis, but sometimes the pathologist plays a crucial role in the differential diagnosis and the patient's management. In this review, the pathologic features of pulmonary vasculitis and the pathologist's role in this field are illustrated.

The Immunobiological Agents for Treatment of Antiglomerular Basement Membrane Disease

Combination therapy with glucocorticoids, cyclophosphamide, and plasmapheresis is recommended as the standard treatment for anti-glomerular basement membrane (anti-GBM) disease, but the prognosis of this disease remains poor. Several immunobiological agents have been administered or are expected to be useful for anti-GBM disease in light of refractory disease or the standard treatments' tolerability. Many data regarding the use of biologic agents for anti-GBM disease have accumulated, verifying the effectiveness and potential of biologic agents as a new treatment option for anti-GBM disease. Tumor necrosis factor (TNF) inhibitors were shown to be useful in animal studies, but these agents have no clinical use and were even shown to induce anti-GBM disease in several cases. Although the efficacy of the TNF-receptor antagonist has been observed in animal models, there are no published case reports of its clinical use. There are also no published reports of animal or clinical studies of anti-B-cell-activating factor, which is a member of the TNF family of agents. Anti-interleukin (IL)-6 antibodies have been demonstrated to have no effect on or to exacerbate nephritis in animal models. Anti-C5 inhibitor was observed to be useful in a few anti-GBM disease cases. Among the several immunobiological agents, only rituximab has been demonstrated to be useful in refractory or poor-tolerance patients or small uncontrolled studies. Rituximab is usually used in combination with steroids and plasma exchange and is used primarily as an alternative to cyclophosphamide, but there is insufficient evidence regarding the efficacy of rituximab for anti-GBM disease, and thus, randomized controlled studies are required.

Hemoptysis of Uncertain Cause Leading to Delayed Diagnosis in an Elderly Lady With Anti-glomerular Basement Membrane Disease

Anti-glomerular basement membrane (GBM) disease or Goodpasture syndrome is a rare disorder characterized by anti-GBM autoantibodies targeting the type 4 collagen of the basement membrane, resulting in rapidly progressive glomerulonephritis with or without alveolar hemorrhage. Pulmonary manifestations are less common in the elderly. Isolated pulmonary manifestations are rare in all age groups, and even more so in the elderly. We present the case of a lady in her late 70s, who presented initially with massive hemoptysis in the absence of renal dysfunction, which was presumed to be secondary to underlying bronchiectasis and infection. However, she later developed rapidly progressive acute kidney injury despite improvement in pulmonary symptoms and was diagnosed with anti-GBM disease. The delay in diagnosis and subsequent treatment due to the atypical presentation resulted in irreversible renal injury and the need for lifelong dialysis. This case demonstrates the need to consider atypical presentations of rare disorders, to ensure early diagnosis and optimal prognosis, especially when the clinical history cannot be explained by findings on examination and investigation.

Unleashing the power of complement activation: unraveling renal damage in human anti-glomerular basement membrane disease

Anti-glomerular basement membrane (GBM) disease is a rare but life-threatening autoimmune disorder characterized by rapidly progressive glomerulonephritis with or without pulmonary hemorrhage. Renal biopsies of anti-GBM patients predominantly show linear deposition of IgG and complement component 3 (C3), indicating a close association between antigen-antibody reactions and subsequent complement activation in the pathogenesis of the disease. All three major pathways of complement activation, including the classical, lectin, and alternative pathways, are involved in human anti-GBM disease. Several complement factors, such as C3, C5b-9, and factor B, show a positive correlation with the severity of the renal injury and act as risk factors for renal outcomes. Furthermore, compared to patients with single positivity for anti-GBM antibodies, individuals who are double-seropositive for anti-neutrophil cytoplasmic antibody (ANCA) and anti-GBM antibodies exhibit a unique clinical phenotype that lies between ANCA-associated vasculitis (AAV) and anti-GBM disease. Complement activation may serve as a potential "bridge" for triggering both AAV and anti-GBM conditions. The aim of this article is to provide a comprehensive review of the latest clinical evidence regarding the role of complement activation in anti-GBM disease. Furthermore, potential therapeutic strategies targeting complement components and associated precautions are discussed, to establish a theoretical basis for complement-targeted therapies.

Rituximab for the Treatment of Anti-glomerular Basement Membrane Disease with Isolated Diffuse Alveolar Hemorrhage

Anti-glomerular basement membrane (GBM) disease with isolated diffuse alveolar hemorrhage (DAH) is rare. We herein report a 91-year-old man admitted with hypoxia and diagnosed with anti-GBM disease with DAH based on positive bronchoalveolar lavage and serum antibody test results. There was no renal involvement. Although remission was achieved using glucocorticoids and plasmapheresis, the patient experienced DAH relapse one week after the last plasmapheresis. Rituximab 375 mg/m2 was administered 4 times weekly; thereafter, DAH relapse was not observed, and the glucocorticoid dosage was tapered. Rituximab was thus effective in treating anti-GBM disease with isolated DAH in an extremely elderly patient.

Pulmonary renal syndrome: a clinical review

The term "pulmonary renal syndrome" describes a clinical syndrome which is characterised by the presence of both diffuse alveolar haemorrhage and glomerulonephritis. It encompasses a group of diseases with distinctive clinical and radiological manifestations, as well as different pathophysiological processes. The most common diseases implicated are anti-neutrophil cytoplasm antibodies (ANCA)-positive small vessel vasculitis and anti-glomerular basement membrane (anti-GBM) disease. Prompt recognition is required as respiratory failure and end-stage renal failure can rapidly occur. Treatment includes a combination of glucocorticoids, immunosuppression, plasmapheresis and supportive measures. The use of targeted treatments has significantly reduced mortality. Thus, an understanding of pulmonary renal syndrome is essential for the respiratory physician.

Anti-glomerular basement membrane disease in children: a brief overview

Anti-glomerular basement membrane disease (Anti-GBM), previously known as Goodpasture syndrome, is an extremely rare cause of rapidly progressive glomerulonephritis and chronic kidney disease stage 5 (CKD5) in children. It is associated with acute pulmonary haemorrhage and it has a poor prognosis. It is classified as an autoimmune, small-vessel vasculitis caused by autoantibody formation against the alpha-3 chain in type IV collagen found in the glomerular basement membrane. Evidence of anti-GBM antibodies in serum or histologically are required for diagnosis. Treatment in children is based on very limited adult data and often involves the use of acute apheresis to rapidly remove circulating factors coupled with intensive immunosuppression such as cyclophosphamide and intravenous corticosteroids. There is also an emerging role for the use of biologic agents such as B cell depletion. The evidence base in children with anti-GBM disease is extremely limited. Multi-centre international collaboration is required to provide insight into this disease, better describe its prognosis and work towards improving outcomes. This review article summarises the key features of this disease in children, highlights treatment options and considers areas of unmet need.

Accuracy of Anti-GBM Antibodies in Diagnosing Anti-Glomerular Basement Membrane Disease: A Systematic Review and Meta-Analysis

BACKGROUND

The sensitivity and specificity of anti-glomerular basement membrane (GBM) antibodies have not been systematically analyzed. In this systematic review, we aimed to evaluate the diagnostic accuracy of anti-GBM antibodies for anti-GBM disease.

SUMMARY

Potential studies were searched using MEDLINE, Embase, the Cochrane Library, and the International Clinical Trials Registry Platform based on the index test and target condition. The inclusion criteria were prospective or retrospective cohort studies or case-control studies assessing the sensitivity and specificity of anti-GBM antibodies, and the reference standard was clinical diagnosis including biopsy results. The exclusion criteria were review articles, case reports, animal studies, and in vitro studies. Quality assessment was conducted based on the Quality Assessment of Diagnostic Accuracy Studies-2. The pooled estimates of sensitivity and specificity were calculated using a bivariate random-effects model. The overall quality was evaluated using the Grades of Recommendation, Assessment, Development, and Evaluation. Six studies (1,691 patients) and 11 index tests were included in our systematic review. A high risk of bias and concerns regarding the applicability of patient selection were noted because of the case-control design in 67% of the included studies. The pooled sensitivity and specificity were 93% (95% CI: 84-97%) and 97% (95% CI: 94-99%), respectively. The certainty of evidence was low because of the high risk of bias and indirectness. Key Messages: Anti-GBM antibodies may exhibit high sensitivity and specificity in the diagnosis of anti-GBM disease. Further cohort studies are needed to confirm their precise diagnostic accuracy and compare diagnostic accuracies among different immunoassays.

Double-Positive Anti-GBM and ANCA-MPO Vasculitis Presenting With Crescentic Glomerulonephritis

We report the case of a 61-year-old man with rapidly progressing glomerulonephritis (RPGN) due to double-positive anti-neutrophil cytoplasmic antibodies (ANCA) and anti-glomerular basement membrane antibodies (GBM) vasculitis. The past medical history included stable untreated psoriatic arthritis and arterial hypertension. He presented with asthenia, anorexia, and rapidly deteriorating renal function with metabolic acidosis and hyperkalemia evolving with the need for hemodialysis. No nephrotoxic drugs were identified. Urinalysis showed proteinuria, erythrocyturia, and mild leukocyturia with no pathological casts and renal ultrasound excluded obstruction as the cause of the acute kidney injury. The subsequent study established the diagnosis of double-positive ANCA and anti-GBM vasculitis with renal biopsy confirming the presence of crescentic glomerulonephritis. The patient was started on corticosteroids, cyclophosphamide, and plasmapheresis with the improvement of symptoms and decrease of antibody titers. The renal function recovery was not obtained and referral for transplantation is ongoing.

A Review of Clinical and Imaging Features of Diffuse Pulmonary Hemorrhage

OBJECTIVE. The purpose of this article is to review the clinical and imaging features of diffuse pulmonary hemorrhage. CONCLUSION. Diffuse pulmonary hemorrhage is a life-threatening syndrome associated with a wide variety of underlying pathologic categories. Nonspecific clinical and imaging features pose challenges to promptly diagnosing this condition. Chest radiography commonly shows alveolar opacification, and CT reveals the extent of disease. Integration of clinical, radiologic, laboratory, and pathologic findings facilitates timely diagnosis and etiologic identification.

Recurrent, Atypical Anti-Glomerular Basement Membrane Disease

Anti-glomerular basement membrane disease (GBM) (Goodpasture's disease) typically presents with acute manifestations of rapidly progressive glomerulonephritis often accompanied by lung haemorrhage. Anti-GBM disease is usually monophasic. However, atypical presentations with indolent renal involvement are being increasingly recognized. Herein we report a patient who presented with lung haemorrhage, minimal renal involvement, and negative result for serum anti-GBM antibody, while immunofluorescence examination of the renal biopsy provided the diagnosis leading to the institution right treatment with excellent response. Interestingly, he had presented 10 years earlier with lung hemorrhage, more significant renal involvement clinically and histologically, with positive serum anti-GBM antibody. The present case is intended to increase our awareness regarding the variable presentations of anti-GBM disease, such as with negative serology and recurrence of anti-GBM disease. The presentation of anti-GBM nephritis with non-proliferative, non-crescentic glomerulonephritis is also highlighted. The possible explanations for negative serum anti-GBM antibody are explored with a brief review of literature.

Anti-glomerular basement membrane disease: A clinicomorphological study of 16 cases

Introduction

Antiglomerular basement membrane disease manifests as rapidly progressive glomerulonephritis and alveolar hemorrhage. It encompasses 10-15% of crescentic glomerulonephritis and is associated with poor outcome. In this study, we have elaborated on the clinical details, morphological features, and outcome of anti-GBM glomerulonephritis.

Materials and Methods

All the consecutive biopsy-proven cases of anti-GBM glomerulonephritis over a period of 4½ years were analyzed, retrospectively.

Results

Sixteen cases were diagnosed as anti-GBM glomerulonephritis during the study period. Twelve patients presented with rapidly progressive renal failure of which four patients required hemodialysis at the time of presentation. Goodpasture's syndrome was noted in two patients. Thirteen cases were positive for circulating anti-GBM antibodies and two patients showed double positivity for both anti-GBM antibodies and ANCA. Fifteen biopsies revealed crescentic glomerulonephritis with linear deposition of IgG along the glomerular basement membrane in all the 16 cases.

Conclusion

Renal biopsy analysis is important in the diagnosis of Anti GBM nephritis. Morphology is an important predictor of disease progression.

Diffuse alveolar hemorrhage, a rare presentation of polymyositis

Background

Diffuse alveolar hemorrhage is a medical emergency caused by persistent and recurrent pulmonary hemorrhage [1]. It is an uncommon presentation of polymyositis. Symptoms of polymyositis include fatigue, muscle pains, proximal muscle weakness, and joint pains [2].

Case presentation

A 44-year-old male presented with new onset shortness of breath and productive cough with white sputum and occasional hemoptysis. The patient was diagnosed with diffuse alveolar hemorrhage (DAH) via bronchoscopy and discharged initially on prednisone. The patient's laboratory work indicated positive titers of ANA & anti-Jo-1 antibody with low complement levels. These results pointed towards the diagnosis of polymyositis [3]. DAH can also be caused by systemic lupus erythematosus, Goodpasture's syndrome, Sjogren syndrome, anticoagulant therapy, and antiphospholipid antibody syndrome [4]. However, the possibility of these potential causes was excluded.

Conclusion

This case of diffuse alveolar hemorrhage was most likely due to polymyositis.

A Man in His 50s With Hemoptysis, Dyspnea, and Bilateral Patchy Ground-Glass Opacities

CASE PRESENTATION

A man in his 50s presented to the ED with a 3-day history of small-volume hemoptysis and new-onset dyspnea. The patient did not have fevers, chills, chest pain, abdominal pain, or changes in urination. His medical history included hypertension, a 35-pack-year active smoking history, and occupational hydrocarbon exposure as a mechanic in the foresting industry. He reported no recent travels, and he denied sick contacts. His medications included amlodipine, hydrochlorothiazide, lisinopril, omeprazole, and nicotine replacement therapy.

[Successful rituximab treatment of recurrent glomerulonephritis associated with antibodies against the glomerular basement membrane]

This article presents a case of recurrent anti-GBM disease (with antibodies against the glomerular basement membrane [GBM]) in a 17-year-old patient successfully treated with rituximab. Kidney biopsy with detection of linear deposition of immunoglobulin G (IgG) along the basement membrane is the diagnostic gold standard, which should be accompanied by serological testing. However, standard assays for the detection of anti-GBM antibodies have a high rate of false-negative results. In this particular case, an increase in proteinuria despite standard therapy (plasmapheresis, steroids, cyclophosphamide) was the clinical correlate of relapsing disease. The use of rituximab completely resolved the recurrent anti-GBM disease.

Anti-glomerular basement membrane disease: an update on subgroups, pathogenesis and therapies

Most patients with anti-glomerular basement membrane (anti-GBM) disease present with rapidly progressive glomerulonephritis with or without pulmonary haemorrhage; however, there are several variants and vigilance is necessary to make a correct diagnosis. Such variants include overlap with anti-neutrophil cytoplasm antibodies-associated vasculitis and membranous nephropathy as well as anti-GBM occurring de novo after renal transplantation. Moreover, patients can present with isolated pulmonary haemorrhage as well as with negative tests for circulating anti-GBM. Virtually all patients with anti-GBM disease have autoantibodies that react with two discrete epitopes on the α3 chain of type IV collagen. Recent evidence suggests that healthy persons have low-affinity natural antibodies reacting with the same epitopes, but most people are protected from developing disease-causing high-affinity autoantibodies by human leukocyte antigen-dependent regulatory T-cells (Tregs). The α3 chain-derived peptides presented by the HLA-DR15 antigen lack the ability to promote the development of such Tregs. The detection of anti-GBM in circulation using the rapid assay test has led to early diagnosis and improved prognosis. However, our present tools to curb the inflammation and to eliminate the assaulting antibodies are insufficient. Only about one-third of all patients survive with functioning native kidneys. More effective therapies need to be developed; agents that inhibit neutrophil recruitment, deplete B cells and cleave immunoglobulin G (IgG) in vivo may become new weapons in the arsenal to combat anti-GBM disease.

Inpatient Burden and Mortality of Goodpasture's Syndrome in the United States: Nationwide Inpatient Sample 2003-2014

Background: Goodpasture’s syndrome is a rare, life-threatening, small vessel vasculitis. Given its rarity, data on its inpatient burden and resource utilization are lacking. We conducted this study aiming to assess inpatient prevalence, mortality, and resource utilization of Goodpasture’s syndrome in the United States. Methods: The 2003–2014 National Inpatient Sample was used to identify patients with a principal diagnosis of Goodpasture’s syndrome. The inpatient prevalence, clinical characteristics, in-hospital treatment, end-organ failure, mortality, length of hospital stay, and hospitalization cost were studied. Multivariable logistic regression was performed to identify independent factors associated with in-hospital mortality. Results: A total of 964 patients were admitted in hospital with Goodpasture’s syndrome as the principal diagnosis, accounting for an overall inpatient prevalence of Goodpasture’s syndrome among hospitalized patients in the United States of 10.3 cases per 1,000,000 admissions. The mean age of patients was 54 ± 21 years, and 47% were female; 52% required renal replacement therapy, whereas 39% received plasmapheresis during hospitalization. Furthermore, 78% had end-organ failure, with renal failure and respiratory failure being the two most common end-organ failures. The in-hospital mortality rate was 7.7 per 100 admissions. The factors associated with increased in-hospital mortality were age older than 70 years, sepsis, the development of respiratory failure, circulatory failure, renal failure, and liver failure, whereas the factors associated with decreased in-hospital mortality were more recent year of hospitalization and the use of therapeutic plasmapheresis. The median length of hospital stay was 10 days. The median hospitalization cost was $75,831. Conclusion: The inpatient prevalence of Goodpasture’s syndrome in the United States is 10.3 cases per 1,000,000 admissions. Hospitalization of patients with Goodpasture’s syndrome was associated with high hospital inpatient utilization and costs.

An uncommon presentation of a rare disease: A case of anti-glomerular basement membrane disease without renal involvement

Anti-glomerular basement membrane disease (anti-GBM) is a well-documented, small vessel vasculitis that is classically associated with glomerulonephritis and alveolitis [1]. However, regardless of clinical process, not every patient will present with a constellation of classically associated symptoms. Literature review demonstrates that early anti-GBM disease can present as glomerulonephritis without alveolitis [2,3]. In this case report, we describe the unique clinical course of a 26-year-old male who originally presented with hemoptysis and his subsequent clinical workup revealing anti-glomerular basement membrane disease without renal involvement.

[Review on anti-glomerular basement membrane disease or Goodpasture's syndrome]

Anti-glomerular basement membrane (anti-GBM) disease or Goodpasture's syndrome is a small vessel vasculitis affecting the capillary beds of kidneys and lungs. It is an autoimmune disease mediated by autoantibodies targeting the glomerular and alveolar basement membranes, leading to pneumorenal syndrome. It is a rare, monophasic and severe disease, associating rapidly progressive glomerulonephritis and alveolar hemorrhage. The presence of antineutrophil cytoplasmic antibodies (ANCA) is reported in 20 to 60% of cases. Management should be prompt and combine plasma exchange with systemic corticosteroids and immunosuppressive therapy by cyclophosphamide. The objective of this review is: 1) to describe the pathogenesis, clinical and histological features of the disease; 2) to characterize double-positive anti-GBM/ANCA patients; 3) to highlight the prognostic factors of renal and global survival, and 4) to focus on the treatment of anti-GBM disease.

Guidelines on the Use of Therapeutic Apheresis in Clinical Practice - Evidence-Based Approach from the Writing Committee of the American Society for Apheresis: The Eighth Special Issue

The American Society for Apheresis (ASFA) Journal of Clinical Apheresis (JCA) Special Issue Writing Committee is charged with reviewing, updating and categorizing indications for the evidence-based use of therapeutic apheresis (TA) in human disease. Since the 2007 JCA Special Issue (Fourth Edition), the committee has incorporated systematic review and evidence-based approaches in the grading and categorization of apheresis indications. This Eighth Edition of the JCA Special Issue continues to maintain this methodology and rigor in order to make recommendations on the use of apheresis in a wide variety of diseases/conditions. The JCA Eighth Edition, like its predecessor, continues to apply the category and grading system definitions in fact sheets. The general layout and concept of a fact sheet that was introduced in the Fourth Edition, has largely been maintained in this edition. Each fact sheet succinctly summarizes the evidence for the use of TA in a specific disease entity or medical condition. The Eighth Edition comprises 84 fact sheets for relevant diseases and medical conditions, with 157 graded and categorized indications and/or TA modalities. The Eighth Edition of the JCA Special Issue seeks to continue to serve as a key resource that guides the utilization of TA in the treatment of human disease.

Atypical Goodpasture's disease: a clinical case report and literature review

Goodpasture's disease (anti-GBM disease) is a rare small vessels vasculitis characterized by the presence of autoantibodies directed against the glomerular basement membrane (GBM) and alveolar basement membrane. Common feature of anti-GBM disease is a combination of rapidly progressive glomerulonephritis and alveolar hemorrhage (pulmonary-renal syndrome). We present a case of atypical disease course in a young male patient who developed alveolar hemorrhage without renal failure. The only symptom of renal involvement was isolated hematuria. Plasmapheresis combined with immunosuppression (cyclophosphamide and corticosteroids) was effective. We present a review of state-of-art data on the pathogenesis and disease course of anti-GBM disease.

[Pulmonary hemorrhage in rheumatic diseases]

In the article, we report the causes of pulmonary hemorrhage (PH) according to the literature data and own experience, with an emphasis on patients suffering from rheumatic diseases. Methods of diagnosis and modern approaches to the treatment of PH are analyzed.

Antibody-Negative Relapse of Goodpasture Syndrome with Pulmonary Hemorrhage

Goodpasture syndrome is a rare autoimmune disease comprising antiglomerular basement membrane (anti-GBM) crescentic glomerulonephritis and pulmonary capillaritis with circulating anti-GBM antibodies. Rarely, antibody-negative cases have been described. We report a young, African American adult woman admitted with flank pain and hematuria with laboratory testing and kidney biopsy demonstrating anti-GBM crescentic glomerulonephritis with elevated anti-GBM antibody levels. She received treatment but remained dialysis-dependent. She was seronegative and clinically stable until she presented 8 months later with dyspnea and hemoptysis requiring mechanical ventilation. Bronchoscopy revealed diffuse alveolar hemorrhage. She was treated for relapse of Goodpasture syndrome. However, anti-GBM antibodies were undetectable. This case emphasizes prompt diagnosis and treatment of Goodpasture syndrome to preserve renal function. Additionally, clinical manifestations of Goodpasture syndrome and its degree of activity do not necessarily correlate with the actual antibody titer on relapse. Clinicians should have enhanced awareness of this atypical presentation of a rare disease.

Hémorragies intra-alvéolaires

L’hémorragie intra-alvéolaire (HIA), maladie rare, est une urgence thérapeutique, car elle peut conduire rapidement vers une insuffisance respiratoire aiguë asphyxiante avec décès. La triade, hémoptysie–anémie–infiltrat radiologique, suggère le diagnostic d’HIA, mais elle peut manquer dans deux tiers des cas, y compris chez des patients en détresse respiratoire. La tomodensitométrie thoracique peut aider dans les formes atypiques. Le diagnostic d’HIA repose sur la réalisation d’un lavage bronchoalvéolaire. Les étiologies en sont très nombreuses. Il importera de séparer, en urgence, les HIA d’origine non immune, avec un dépistage de celles d’origine septique qui doivent bénéficier d’une enquête microbiologique ciblée et cardiovasculaire avec la réalisation d’une échographie cardiaque, des HIA immunes (les vascularites liées aux anticorps anticytoplasme des polynucléaires neutrophiles, les connectivites et le syndrome de Goodpasture), avec la recherche d’autoanticorps et la réalisation de biopsies au niveau des organes facilement accessibles. La biopsie pulmonaire doit rester exceptionnelle. En cas d’HIA immune inaugurale, un traitement par stéroïdes et cyclophosphamide peut être débuté. Les indications du rituximab commencent à être mieux établies. Le bénéfice des échanges plasmatiques est débattu. En cas de réapparition d’infiltrats pulmonaires, chez un patient suivi pour une HIA immune, on s’efforcera d’écarter une infection dans un premier temps.

Clinical mimics: an emergency medicine focused review of pneumonia mimics

Pneumonia is a common cause of morbidity and mortality in adults in the United States. While pneumonia classically presents with a fever, cough, and shortness of breath, the presentation can vary widely in adults. This review evaluates history and physical examination findings of pneumonia and several conditions that mimic pneumonia. Pneumonia is a potentially deadly disease. History and examination findings are variable in pneumonia, and many conditions mimic pneumonia. These conditions include pulmonary embolism, diffuse interstitial lung disease, endocarditis, vasculitis, diffuse alveolar hemorrhage, acute decompensated heart failure, tuberculosis, lung cancer, and acute respiratory distress syndrome. Emergency clinicians should assess the patient while resuscitation occurs. Early antibiotics and the diagnosis of pneumonia can improve outcomes. Key historical and physical examination findings may lead the clinician to consider other conditions that require immediate management. Using clinical evaluation and adjunctive imaging, these conditions can be diagnosed and treated. Knowledge of pneumonia mimics is vital for the care of patients with respiratory complaints. Pneumonia is common and may be deadly, and emergency clinicians must differentiate conditions that mimic pneumonia. Rapid evaluation and management may alleviate morbidity and mortality for each of these conditions. The history and physical examination, in addition to utilizing imaging modalities such as ultrasound and computed tomography, are vital in diagnosis of pneumonia mimics.

An Official American Thoracic Society Workshop Report: Translational Research in Rare Respiratory Diseases

Rare respiratory diseases (RRDs) are a heterogeneous group of disorders that collectively represent a significant health care burden. In recent years, strong advocacy and policy initiatives have led to advances in the implementation of research and clinical care for rare diseases. The development of specialized centers and research networks has facilitated support for affected individuals as well as emerging programs in basic, translational, and clinical research. In selected RRDs, subsequent gains in knowledge have informed the development of targeted therapies and effective diagnostic tests, but many gaps persist. There was therefore a desire to identify the elements contributing to an effective translational research program in RRDs. To this end, a workshop was convened in October 2015 with a focus on the implementation of effective transnational research networks and collaborations aimed at developing novel diagnostic and therapeutic tools. Key elements included an emphasis on molecular pathogenesis, the continuing engagement of patient advocacy groups and policy makers, the effective use of preclinical models in the translational research pipeline, and the detailed phenotyping of patient cohorts. During the course of the workshop, current logistical and knowledge gaps were identified, and new solutions or opportunities were highlighted.

Anti-Glomerular Basement Membrane Disease

Anti-glomerular basement membrane (anti-GBM) disease is a rare small vessel vasculitis that affects the capillary beds of the kidneys and lungs. It is an archetypic autoimmune disease, caused by the development of directly pathogenic autoantibodies targeting a well characterized autoantigen expressed in the basement membranes of these organs, although the inciting events that induce the autoimmune response are not fully understood. The recent confirmation of spatial and temporal clustering of cases suggests that environmental factors, including infection, may trigger disease in genetically susceptible individuals. The majority of patients develop widespread glomerular crescent formation, presenting with features of rapidly progressive GN, and 40%-60% will have concurrent alveolar hemorrhage. Treatment aims to rapidly remove pathogenic autoantibody, typically with the use of plasma exchange, along with steroids and cytotoxic therapy to prevent ongoing autoantibody production and tissue inflammation. Retrospective cohort studies suggest that when this combination of treatment is started early, the majority of patients will have good renal outcome, although presentation with oligoanuria, a high proportion of glomerular crescents, or kidney failure requiring dialysis augur badly for renal prognosis. Relapse and recurrent disease after kidney transplantation are both uncommon, although de novo anti-GBM disease after transplantation for Alport syndrome is a recognized phenomenon. Copresentation with other kidney diseases such as ANCA-associated vasculitis and membranous nephropathy seems to occur at a higher frequency than would be expected by chance alone, and in addition atypical presentations of anti-GBM disease are increasingly reported. These observations highlight the need for future work to further delineate the immunopathogenic mechanisms of anti-GBM disease, and how to better refine and improve treatments, particularly for patients presenting with adverse prognostic factors.

Anti-glomerular basement membrane disease: Case series from a tertiary center in North India

Anti-glomerular basement (anti-GBM) disease is an uncommon disorder with a bimodal age of presentation. Patients presenting with dialysis-dependent renal failure have poor renal outcomes. There is limited data regarding the clinical presentation and outcomes of anti-GBM disease from India. We conducted this prospective study to analyze the clinical presentation and outcomes of anti-GBM disease at a large tertiary care hospital in North India over 1½ years. Subjects with a biopsy proven anti-GBM disease (light microscopic examination showing crescents and immunofluorescence examination showing linear deposition of IgG) with or without positive anti-GBM antibodies in serum were included in the study and followed-up for at least 12 months. All the patients were treated with steroids, cyclophosphamide, and plasma exchange. A total of 17 patients (nine males) were included. The mean age at presentation was 39.11 ± 16.58 (range 11-72) years. Twelve patients (70%) presented with rapidly progressive glomerulonephritis (RPGN), 4 (23.5%) presented with Goodpasture syndrome, while 1 (5.8%) had nephritic syndrome, 7 (41%) were hypertensive, and 14 (82.3%) required dialysis at the time of presentation. Four patients (23.5%) had associated anti-neutrophil cytoplasmic antibody positivity (anti-myeloperoxidase antibodies in all). Fourteen (87.5%) patients had crescentic glomerulonephritis, while 5 (31.25%) showed necrotizing (n = 4) or granulomatous (n = 1) in the vasculitis. Of 16 patients who received treatment, four (23.25%) achieved complete remission. In this single-center study, the majority of anti-GBM disease patients presented with RPGN and had crescentic glomerulonephritis on biopsy with poor treatment outcome.

Guidelines on the Use of Therapeutic Apheresis in Clinical Practice-Evidence-Based Approach from the Writing Committee of the American Society for Apheresis: The Seventh Special Issue

The American Society for Apheresis (ASFA) Journal of Clinical Apheresis (JCA) Special Issue Writing Committee is charged with reviewing, updating, and categorizing indications for the evidence-based use of therapeutic apheresis in human disease. Since the 2007 JCA Special Issue (Fourth Edition), the Committee has incorporated systematic review and evidence-based approaches in the grading and categorization of apheresis indications. This Seventh Edition of the JCA Special Issue continues to maintain this methodology and rigor to make recommendations on the use of apheresis in a wide variety of diseases/conditions. The JCA Seventh Edition, like its predecessor, has consistently applied the category and grading system definitions in the fact sheets. The general layout and concept of a fact sheet that was used since the fourth edition has largely been maintained in this edition. Each fact sheet succinctly summarizes the evidence for the use of therapeutic apheresis in a specific disease entity. The Seventh Edition discusses 87 fact sheets (14 new fact sheets since the Sixth Edition) for therapeutic apheresis diseases and medical conditions, with 179 indications, which are separately graded and categorized within the listed fact sheets. Several diseases that are Category IV which have been described in detail in previous editions and do not have significant new evidence since the last publication are summarized in a separate table. The Seventh Edition of the JCA Special Issue serves as a key resource that guides the utilization of therapeutic apheresis in the treatment of human disease. J. Clin. Apheresis 31:149-162, 2016. © 2016 Wiley Periodicals, Inc.

Basement membranes and autoimmune diseases

Basement membrane components are targets of autoimmune attack in diverse diseases that destroy kidneys, lungs, skin, mucous membranes, joints, and other organs in man. Epitopes on collagen and laminin, in particular, are targeted by autoantibodies and T cells in anti-glomerular basement membrane glomerulonephritis, Goodpasture's disease, rheumatoid arthritis, post-lung transplant bronchiolitis obliterans syndrome, and multiple autoimmune dermatoses. This review examines major diseases linked to basement membrane autoreactivity, with a focus on investigations in patients and animal models that advance our understanding of disease pathogenesis. Autoimmunity to glomerular basement membrane type IV is discussed in depth as a prototypic organ-specific autoimmune disease yielding novel insights into the complexity of anti-basement membrane immunity and the roles of genetic and environmental susceptibility.

Frequently relapsing anti-glomerular basement membrane antibody disease with changing clinical phenotype and antibody characteristics over time

Anti-glomerular basement membrane (GBM) antibody disease is a typically monophasic autoimmune disease with severe pulmonary and renal involvement. We report an atypical case of frequently relapsing anti-GBM antibody disease with both anti-GBM antibody-positive flares with pulmonary and renal involvement, and anti-GBM antibody-negative flares that were pulmonary limited with no histologic renal disease. This is the first report of alternating disease phenotype and anti-GBM antibody status over time. Disease severity paralleled the detection of anti-GBM antibodies but was independent of IgG subtype staining along the GBM. This case suggests a role for changing subpopulations of pathogenic antibodies as an explanation for variation in disease phenotype and anti-GBM antibody results.

Multiple recurrences of anti-glomerular basement membrane disease with variable antibody detection: can the laboratory be trusted?

Anti-glomerular basement membrane (GBM) disease is commonly a monophasic illness. We present the case of multiple recurrences of anti-GBM disease with varying serum anti-GBM antibody findings. A 33-year-old female tobacco user presenting with hematuria was diagnosed with anti-GBM disease by renal biopsy. Five years later, she presented with alveolar hemorrhage and positive anti-GBM antibody. She presented a third time with alveolar hemorrhage but undetectable anti-GBM antibody. With each occurrence, symptoms resolved with plasmapheresis, intravenous methylprednisone and oral cyclophosphamide. The relationship between anti-GBM antibody findings and disease presentation is complex. Clinicians should be aware of the possibility of seronegative anti-GBM disease.

Atypical anti-glomerular basement membrane disease

Background

Anti-glomerular basement membrane (anti-GBM) disease classically presents with aggressive necrotizing and crescentic glomerulonephritis, often with pulmonary hemorrhage. The pathologic hallmark is linear staining of GBMs for deposited immunoglobulin G (IgG), usually accompanied by serum autoantibodies to the collagen IV alpha-3 constituents of GBMs.

Methods

Renal pathology files were searched for cases with linear anti-GBM to identify cases with atypical or indolent course. Histopathology, laboratory studies, treatment and outcome of those cases was reviewed in detail.

Results

Five anti-GBM cases with atypical clinicopathologic features were identified (accounting for ∼8% of anti-GBM cases in our laboratory). Kidney biopsies showed minimal glomerular changes by light microscopy; one patient had monoclonal IgG deposits in an allograft (likely recurrent). Three patients did not have detectable serum anti-GBM by conventional assays. Three patients had indolent clinical courses after immunosuppressive treatment. One patient, untreated after presenting with brief mild hematuria, re-presented after a short interval with necrotizing and crescentic glomerulonephritis.

Conclusions

Thorough clinicopathologic characterization and close follow-up of patients with findings of atypical anti-GBM on renal biopsy are needed. Review of the literature reveals only rare well-documented atypical anti-GBM cases to date, only one of which progressed to end-stage kidney disease.

Goodpasture's Disease: An Uncommon Disease With an Atypical Clinical Course

Goodpasture’s disease is an uncommon composite of features including renal failure with pulmonary hemorrhage secondary to an autoimmune response that specifically targets these organ systems. We present a case of particular interest in regards to atypical presentation, and the uncommon treatment that the patient underwent. A 65-year-old Afghani female arrived with complaints of nausea, vomiting, loss of appetite, malaise, decreased urine output, exertional dyspnea, and cough. The patient presented initially with renal failure and unexpectedly developed respiratory failure after hemodialysis. Initial CT of thorax revealed diffuse bilateral pulmonary edema. Subsequently, the patient received a bronchoscopy demonstrating alveolar hemorrhage, which highlights a clinician’s need to maintain a differential and reassess patients. Anti-GBM antibody in the serum was detected and the renal biopsy revealed evidence of the antibody on immunofluorescence. In regards to management, the patient could only be treated with plasmapheresis as she had contraindication to initiation of immunosuppression, after which she showed significant clinical improvement. We would like to highlight the benefit of plasmapheresis without concomitant immunosuppression and recommend such an approach to be considered in similar clinical scenarios, where contraindication for immunosuppressant therapy exists.

Severe Uncompensated Metabolic Alkalosis due to Plasma Exchange in a Patient with Pulmonary-Renal Syndrome: A Clinician's Challenge

Metabolic alkalosis secondary to citrate toxicity from plasma exchange is very uncommon in patients with normal renal function. In patients with advanced renal disease this can be a fatal event. We describe a case of middle-aged woman with Goodpasture's syndrome treated with plasma exchange who developed severe metabolic alkalosis. High citrate load in plasma exchange fluid is the underlying etiology. Citrate metabolism generates bicarbonate and once its level exceeds the excretory capacity of kidneys, the severe metabolic alkalosis ensues. Our patient presented with generalized weakness, fever, and oliguria and developed rapidly progressive renal failure. Patient had positive serology for antineutrophilic cytoplasmic antibodies myeloperoxidase (ANCA-MPO) and anti-glomerular basement membrane antibodies (anti-GBM). Renal biopsy showed diffuse necrotizing and crescentic glomerulonephritis with linear glomerular basement membrane staining. Patient did not respond to intravenous steroids. Plasma exchange was started with fresh frozen plasma but patient developed severe metabolic alkalosis. This metabolic alkalosis normalized with cessation of plasma exchange and initiation of low bicarbonate hemodialysis. ANCA-MPO and anti-GBM antibodies levels normalized within 2 weeks and remained undetectable at 3 months. Patient still required maintenance hemodialysis.

Pulmonary vasculitis

Pulmonary vasculitis encompasses inflammation in the pulmonary vasculature with involved vessels varying in caliber from large elastic arteries to capillaries. Small pulmonary capillaries are the vessels most commonly involved in vasculitis affecting the lung. The antineutrophil cytoplasmic antibody-associated vasculitides, which include granulomatosis with polyangiitis (formerly Wegener granulomatosis), microscopic polyangiitis, and eosinophilic granulomatosis with polyangiitis (formerly Churg-Strauss syndrome), are the small vessel vasculitides in which pulmonary vasculitis is most frequently observed and are the major focus of this review. Vasculitic involvement of the large pulmonary vessels as may occur in Behçet syndrome and Takayasu arteritis is also discussed.