The Role of Complement Activation and Possibility of Inhibition by Factor H
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Digitalcommons@UNMC Agranulocytosis
University of Nebraska Medical Center DigitalCommons@UNMC MD Theses Special Collections 5-1-1935 Agranulocytosis Gordon A. Gunn University of Nebraska Medical Center This manuscript is historical in nature and may not reflect current medical research and practice. Search PubMed for current research. Follow this and additional works at: https://digitalcommons.unmc.edu/mdtheses Part of the Medical Education Commons Recommended Citation Gunn, Gordon A., "Agranulocytosis" (1935). MD Theses. 386. https://digitalcommons.unmc.edu/mdtheses/386 This Thesis is brought to you for free and open access by the Special Collections at DigitalCommons@UNMC. It has been accepted for inclusion in MD Theses by an authorized administrator of DigitalCommons@UNMC. For more information, please contact [email protected]. AGRANULOOYTOSIS ,- Senior Thesis by GOrdon .M.. Gunn INTRODUCTION Fifteen years ago the medioal profession new nothing of the disease spoken of in this paper as agranulocytosis. Since Schultz, in 1922, gave an accurate description of a fulminat ing case, agranulocytosis has oomettoClOCo.'UPy more and more prominence in the medical field. Today, the literature is fairly teeming with accounts of isolated cases of all descriptions. Added to this a confus ing nomenclature, varied classifications, and heterogeneous forms of treatment; and the large question of whether it is a disease entity, a group of diseases, or only a symptom complex, and some idea may be garnered as to the progress made. Time is a most important factor in diagnosis of this disease, and the prognosis at best is grave. The treatment has gone through the maze of trials as that of any other new disease; there must be a cause and so there must be some specific treatment. -
Complement Recognition Pathways in Renal Transplantation
BRIEF REVIEW www.jasn.org Complement Recognition Pathways in Renal Transplantation Christopher L. Nauser, Conrad A. Farrar, and Steven H. Sacks Medical Research Council Centre for Transplantation, Division of Transplantation Immunology and Mucosal Biology, King’s College London, National Health Service Guy’s and St. Thomas’ Trust, London, United Kingdom ABSTRACT The complement system, consisting of soluble and cell membrane–bound compo- weigh its effect on organ injury and nents of the innate immune system, has defined roles in the pathophysiology of renal rejection with dampening the antimi- allograft rejection. Notably, the unavoidable ischemia-reperfusion injury inherent to crobial functions of the complement sys- transplantation is mediated through the terminal complement activation products tem, such as opsonisation, cell lysis, and C5a and C5b-9. Furthermore, biologically active fragments C3a and C5a, produced recruitment of neutrophils and other in- during complement activation, can modulate both antigen presentation and T cell flammatory cells.7 It is our belief that priming, ultimately leading to allograft rejection. Earlier work identified renal tubule therapeutic strategies can be designed cell synthesis of C3, rather than hepatic synthesis of C3, as the primary source of C3 to specificallytargetthekeyinitiators driving these effects. Recent efforts have focused on identifying the local triggers of of complement activation at the relevant complement activation. Collectin-11, a soluble C-type lectin expressed in renal tis- location, such as complement-binding sue, has been implicated as an important trigger of complement activation in renal anti-HLA antibodies in the vascular tissue. In particular, collectin-11 has been shown to engage L-fucose at sites of compartment or the initiator(s) of local ischemic stress, activating the lectin complement pathway and directing the innate complement activation in the extravas- immune response to the distressed renal tubule. -
Leukocyte Adhesion Deficiency-I
Clinical Communications Leukocyte adhesion deficiency-I: A this article’s Online Repository at www.jaci-inpractice.org for a comprehensive review of all published comprehensive listing of publications and patient numbers by cases country and Table E2 for a comprehensive listing of references). Elena Almarza Novoa, PhDa,b,*, Per investigator assessment, 113 patients were considered to have severe LAD-I, 63 moderate, and 147 not classified. Sanchali Kasbekar, PharmDc,*, d e Neutrophil CD18 expression was reported for 265 cases and was Adrian J. Thrasher, MD, PhD , Donald B. Kohn, MD , less than 2% in 135 patients (51%) and 2% or more in 130 Julian Sevilla, MD, PhDf, Tony Nguyen, MBAg, patients (49%). Four patients with CD18 greater than or equal Jonathan D. Schwartz, MDc,z, and to 2% were considered to have severe LAD-I (CD18% range, Juan A. Bueren, PhDa,b,z 2.4-17.3). Sex information was available for 282 patients, of which 148 (52%) were males. Clinical Implications Age at presentation was reported for 146 cases. For 63 patients with CD18 less than 2%, median presentation was at age 1 Leukocyte adhesion deficiency-I (LAD-I) is a rare, serious month (range, 0.03-18 months); for 62 patients with CD18 of disorder with severity determined by defective CD18 2% or more, median presentation was at age 6 months (range, expression. LAD-I is characterized by umbilical 0.03-192 months). HSCT was performed for 125 patients; 198 complications, granulocytosis, and diverse infections. patients did not undergo HSCT. Severe LAD-I is frequently fatal before the age of 2 years Infections were described for 248 (77%) of the 323 cases; fi without allogeneic transplant. -
Anti-Thymocyte Globulin (Atg) and Ciclosporin (Csa)
Myeloid group ANTI-THYMOCYTE GLOBULIN (ATG) AND CICLOSPORIN (CSA) INDICATION ATG and CSA is indicated for patients who require treatment for aplastic anaemia (AA) but who are not eligible for sibling donor BMT. This includes (note references to severity are based on the modified Camitta criteria): Patients with non-severe aplastic anaemia who are dependent on red cell and/or platelet transfusions. Patients with severe aplastic anaemia (SAA) or very SAA who are > 35-50 years of age. Patients with SAA or very SAA disease who lack an HLA-compatible sibling donor. Protocol may be used in selected patients with hypoplastic marrow conditions. Patients with severe AA who are ≤ 35 years old and have a HLA identical sibling donor, should be treated with allogenic bone marrow transplantation as soon as possible after diagnosis. TREATMENT INTENT Prolong survival Provide a rapid (within 3 months) and sustained improvement in peripheral blood counts Restore haematopoiesis PRE-ASSESSMENT 1. ATG should only used by physicians familiar with administering ATG. Medical and nursing teams must be aware of the side effects and how to treat promptly and appropriately. 2. ATG is highly immunosuppressive - only use in centres with at least level 2 facilities. Patients should be nursed in a single or double isolation room, as an inpatient. 3. Risk of transfusion-associated GvHD following treatment with ATG is unclear, therefore irradiated blood components are currently recommended. It is not known how long the use of irradiated products This is a controlled document and therefore must not be changed Page 1 of 9 ML.2 ATG & CSA Authorised by Myeloid Lead Oct 2019 V.4.1 Prof Adam Mead Myeloid group should be continued, but it may be reasonable to continue while patients are still taking CSA following ATG therapy. -
Rash During Procedural Sedation for Trimalleolar Fracture
Rash during Procedural Sedation for Trimalleolar Fracture Saint John, Emergency Medicine Case Rounds – 10 October, 2017 Dr. Jacqueline Hiob, BScPharm MD PGY1, FRCP Emergency Medicine Learning points for discussion around… • Response to possible drug reaction during procedural sedation • Options for avoiding or mitigating histamine release reactions to opioids Case 14 y/o M, healthy Fall from bicycle ~ 1 hour prior to presentation to ED No head injury, no LOC c/o pain and swelling R. ankle Unable to ambulate Transport by EMS – pt splinted on route, extremity NVI, Entonox for analgesia Case In the ED…. - Entonox Acetaminophen, Fentanyl - closed R. ankle injury, remains NVI - BP 145/72, P 90, S 96% RA, T 36.8 - off to xray he goes…. Imaging - Comminuted fractures, distal tibia + fibula - Apex medial and posterior angulation - Ankle and growth plate intact Case - Ortho consulted - Ortho R3 arrives in ED to assist with reduction - Full team: ED attending, ED resident, Emerg CC3, Ortho resident, RN, RN (training), RT, RT (student), LPN, X-Ray Tech Case Balanced Procedural Sedation with…. - Fentanyl - Ketamine - Propofol Case - ~ 20 minutes into procedure, macular rash noted over patients chest, progressing over abdomen - - no airway involvement, no hypotension or tachycardia - - decision made to treat with IV diphenhydramine and have epinephrine on hand ** smaller area of involvement than pictured - meds for anaphylaxis not immediately available and nurse sent to retrieve Case - Reduction completed within few minutes of rash presentation - Rash -
• Cytosis: O Neutrophilia: Defined As an Increase in the Neutrophilic Count in the Peripheral Blood Above Reference Range for Age
HENATOLYMPHOID SYSTEM THIRD YEAR MEDICAL STUDENTS-UNIVERSITY OF JORDAN AHMAD T. MANSOUR, MD NONNEOPLASTIC DISEASES OF THE WHITE BLOOD CELLS • There are five major types of WBCs in the blood: neutrophils, lymphocytes, eosinophils, basophils and monocytes. • The normal function of the white blood cells depends on a tight regulation of their count and their function. Therefore, disease develops if there is a derangement of the cells count or function, it takes one of the following forms: o Cytosis: increase in the number of circulating cells above reference range. (Note: leukocytosis means an increase in the WBC count, neutrophilia means increase in the neutrophilic count, lymphocytosis means increase in the lymphocytic count, monocytosis means increase in the monocytic count, basophilia means increase in the basophilic count and eosinophilia means in crease in the eosinophilic count). o Cytopenia: decrease in the number of circulating cells below reference range. (Note: neutropenia means decreased neutrophils, lymphocytopenia, or simply lymphopenia, means decrease in lymphocytes, monocytopenia means decrease in monocytes, eosinopenia means decrease in eosinophils, and basopenia means decrease in basophils). o Abnormal or absent function • Cytosis: o Neutrophilia: defined as an increase in the neutrophilic count in the peripheral blood above reference range for age. o Causes: bacterial infection is the most common and most important etiology. Tissue necrosis in cases of burns or trauma and medications such as epinephrine and corticosteroids are also additional causes for neutrophilia. § Some physiologic conditions can lead to neutrophilia such as stress, smoking and pregnancy. o Pathophysiology: neutrophils are present in the blood in two populations: circulating and marginal (meaning neutrophils stuck to the vessel wall). -
Blood Cell Changes in Complement Activation- Related Pseudoallergy
Eur. J. Nanomed. 2015; 7(3): 233–244 Mini Review Zsófia Patkó* and János Szebeni Blood cell changes in complement activation- related pseudoallergy DOI 10.1515/ejnm-2015-0021 Introduction Received April 13, 2015; accepted May 19, 2015 Complement activation-related pseudoallergy (CARPA), as the name implies, is a non-Ig-E-mediated (pseudo- Abstract: The characteristic physiological changes allergic) hypersensitivity reaction (HSR) that is triggered in complement (C) activation-related pseudoallergy by C activation, or C activation plays a major contributing (CARPA) include thrombocytopenia, leukocytosis and role. CARPA is best known in the context of nanotoxicity, leukopenia with or without compensatory leukocytosis. since nanomedicines, i.e. particulate drugs and agents in In the background of these phenomena it is known that the nano (10−9–10 −6 m) size range often cause such reac- anaphylatoxins, the triggers of CARPA, can activate white tions. As reviewed earlier (1–8), and also discussed in blood cells (WBCs) and platelets, and that this activation other papers of this issue, the phenomenon represents can lead to the binding of these cells to each other and an immune barrier to the clinical use of many promising also to capillary endothelial cells, entailing microthrom- nanomedicines. In essence, CARPA may be perceived as bus formation and circulatory blockage mainly in the pul- a biological stress on blood that arises as a consequence monary and coronary microcirculation. These changes of the similarity of nanomedicines to viruses, between are key contributors to the hemodynamic alterations in which the immune system cannot make difference (8). CARPA, and can lead to anaphylactic shock. -
An Anticomplement Agent That Homes to the Damaged Brain and Promotes Recovery After Traumatic Brain Injury in Mice
An anticomplement agent that homes to the damaged brain and promotes recovery after traumatic brain injury in mice Marieta M. Rusevaa,1,2, Valeria Ramagliab,1, B. Paul Morgana, and Claire L. Harrisa,3 aInstitute of Infection and Immunity, School of Medicine, Cardiff University, Cardiff CF14 4XN, United Kingdom; and bDepartment of Genome Analysis, Academic Medical Center, Amsterdam 1105 AZ, The Netherlands Edited by Douglas T. Fearon, Cornell University, Cambridge, United Kingdom, and approved September 29, 2015 (received for review July 15, 2015) Activation of complement is a key determinant of neuropathology to rapidly and specifically inhibit MAC at sites of complement and disability after traumatic brain injury (TBI), and inhibition is activation, and test its therapeutic potential in experimental TBI. neuroprotective. However, systemic complement is essential to The construct, termed CD59-2a-CRIg, comprises CD59a linked fight infections, a critical complication of TBI. We describe a to CRIg via the murine IgG2a hinge. CD59a prevents assembly targeted complement inhibitor, comprising complement receptor of MAC in cell membranes (16), whereas CRIg binds C3b/iC3b of the Ig superfamily (CRIg) fused with complement regulator CD59a, deposited at sites of complement activation (17). The IgG2a designed to inhibit membrane attack complex (MAC) assembly at hinge promotes dimerization to increase ligand avidity. CD59- sites of C3b/iC3b deposition. CRIg and CD59a were linked via the 2a-CRIg protected in the TBI model, demonstrating that site- IgG2a hinge, yielding CD59-2a-CRIg dimer with increased iC3b/C3b targeted anti-MAC therapeutics may be effective in prevention binding avidity and MAC inhibitory activity. CD59-2a-CRIg inhibited of secondary neuropathology and improve neurologic recovery MAC formation and prevented complement-mediated lysis in vitro. -
I Have Spots and My Skin Burns
I have spots and my skin burns Patient presentation History Differential diagnosis Examination Investigations Discussion Treatment Final Outcome References Evaluation - Questions & answers MCQs Patient presentation Peter, a 60 year-old Caucasian policeman, complains of a painful burning sensation in his lower extremities lasting for several months. Lower limbs petechiae (small purple/red hemorrhagic spots) appeared one week ago. Acknowledgement This case study was provided by Prof. Olivier Boyer (M.D., Ph.D., Head of the Department of Immunology and Biotherapy, Rouen University Hospital, France) and Dr. Maëlle Le Besnerais (M.D., Assistant Professor of Internal Medicine, Rouen University Hospital, France) of the Faculty of Medicine of Rouen, Normandy University, France. The authors would like to thank David Saadoun, Odile Goria, Lucie Guyant-Maréchal and Fabienne Jouen for their critical reading of this case study, Isabelle Duval for the development of pictures and Laetitia Demoulins for technical assistance. We are grateful to Nikki Sabourin-Gibbs, Rouen University Hospital, for her help in editing the manuscript. Immunopaedia.org.za History Peter complains of chronic fatigue and aching joints which started several months ago. He denies significant alcohol consumption and intravenous drug abuse. He received a blood transfusion after a gunshot injury to his arm 35 years ago. He reports distal paraesthesia (tingling or numbness) of both legs and painful burning in both feet which has progressed to the lower and upper limbs. Knee pain wakes him up at night. Past medical history None No allergies Surgical history Appendix removed at 10 years old Arm gunshot injury 35 years ago Family history His father has hypertension and type 2 diabetes Travel history He traveled to Thailand 25 years ago Social history Policeman, married, two children Medication None Differential diagnosis IgA vasculitis Polyarteritis nodosa ANCA-associated vasculitis (eg. -
Penicillin Allergy Guidance Document
Penicillin Allergy Guidance Document Key Points Background Careful evaluation of antibiotic allergy and prior tolerance history is essential to providing optimal treatment The true incidence of penicillin hypersensitivity amongst patients in the United States is less than 1% Alterations in antibiotic prescribing due to reported penicillin allergy has been shown to result in higher costs, increased risk of antibiotic resistance, and worse patient outcomes Cross-reactivity between truly penicillin allergic patients and later generation cephalosporins and/or carbapenems is rare Evaluation of Penicillin Allergy Obtain a detailed history of allergic reaction Classify the type and severity of the reaction paying particular attention to any IgE-mediated reactions (e.g., anaphylaxis, hives, angioedema, etc.) (Table 1) Evaluate prior tolerance of beta-lactam antibiotics utilizing patient interview or the electronic medical record Recommendations for Challenging Penicillin Allergic Patients See Figure 1 Follow-Up Document tolerance or intolerance in the patient’s allergy history Consider referring to allergy clinic for skin testing Created July 2017 by Macey Wolfe, PharmD; John Schoen, PharmD, BCPS; Scott Bergman, PharmD, BCPS; Sara May, MD; and Trevor Van Schooneveld, MD, FACP Disclaimer: This resource is intended for non-commercial educational and quality improvement purposes. Outside entities may utilize for these purposes, but must acknowledge the source. The guidance is intended to assist practitioners in managing a clinical situation but is not mandatory. The interprofessional group of authors have made considerable efforts to ensure the information upon which they are based is accurate and up to date. Any treatments have some inherent risk. Recommendations are meant to improve quality of patient care yet should not replace clinical judgment. -
Letters to the Editor
LETTERS TO THE EDITOR Complications of plasma exchange in after percutaneous insertion of a subclavian central ve- thrombotic thrombocytopenic nous catheter from pneumothorax and hemorrhage. Two purpura-hemolytic uremic syndrome: patients suffered cardiac arrest with pulseless electrical a study of 78 additional patients activity: one from an anaphylactic reaction to plasma and The frequency of patients treated with plasma exchange the other from pericardial hemorrhage and tamponade, (PE) for thrombotic thrombocytopenic purpura- presumably due to cardiac perforation by an internal hemolytic uremic syndrome (TTP-HUS) increased seven- jugular catheter insertion guidewire. fold from 1981 to 1997.1 Therefore, the morbidity and Other major catheter-related complications included mortality due to PE is an increasingly important consid- one patient with a retroperitoneal hemorrhage following eration in management decisions for patients with clini- femoral catheter insertion and seven patients with cath- cally suspected TTP-HUS. Some studies have described eter thrombosis that prevented PE and/or required place- few complications associated with PE,2 but our previous ment of a new central venous catheter; two of these seven report on 71 consecutive patients with clinically sus- patients had catheter-related venous thrombosis requir- pected TTP-HUS treated with PE from 1996 to 1999 dem- ing systemic anticoagulation. Ten patients developed sys- onstrated a major complication rate of 30 percent, in- temic infection: eight had blood cultures positive for the cluding two deaths.3 This report describes our experience presence of bacteria (Staphylococcus aureus [five], Staph- during the subsequent 3 years, 1999 to 2002, with 78 con- ylococcus epidermidis [three]); the two patients with secutive patients. -
Objectives Complement (C') Complement Proteins Functions Of
Complement Objectives Foundations of Public Health Identify functions of complement Immunology Recognize the similarities and differences of the three complement pathways Complement Identify important complement components & their functions Identify deleterious effects of complement activation and deficiency 1 2 Complement (C’) Complement Proteins Synthesized in the liver and by several Series of approximately 30 heat-labile proteins cells types (splenic macrophages) Normally inactive in the serum Plays an essential role in Inactive complement proteins known as zymogens inflammation and in facilitating Can be sequentially activated in a antibody effectiveness controlled sequence Amplification of the reaction occurs at each step Severe infections or autoimmune Production of biologically active fragments diseases can result from complement for lysis or killing of the target deficiencies (rare in the population) 3 4 Functions of Complement Functions of Complement Essential role in inflammation Assists antibodies in effector functions (Antibody Dependent Cell- mediated Cytotoxicity- ADCC) Assist in clearing immune complexes Opsonization and facilitation of phagocytosis No antigen specificity 5 6 1 Complement 3 Pathways of Activation Complement Activators Classical Triggered when IgM or certain IgG subclasses bind antigens Alternative (Properdin) Triggered by the deposition of complement protein, C3b, onto microbial surfaces No antibodies required for activation Lectin Triggered by the attachment of plasma mannose-binding lectin (MBL) to microbes No antibodies required for Activators start the domino effect… activation 7 8 Early Steps Late Steps The initial steps vary between pathways Dependent on activating substance C3 convertase quickly forms in all paths to cleave C3 Watch this well-done animation on the activation of complement, the Late steps (after C5 convertase) are same in all pathways steps in the complement pathways, Lead to formation of MAC & the functions of complement.