Angioedema: Part 3

Acquired angioedema (AAE) is characterized by a deficiency of C1INH not associated with a genetic defect; overactivation of the classical complement pathway; and frequent angioedema episodes. AAE is rare, about ten times less common than HAE. However, the two conditions are clinically identical. AAE often presents with low CH50, C2, C4 and sometimes C1q, with low or poorly functioning C1INH.

AAE was originally associated with lymphoma and has since been found secondary to a number of autoimmune and hematologic diseases, particularly lymphoproliferative conditions and monoclonal gammopathy of unknown significance (MGUS, which often precedes multiple myeloma). Historically, AAE has been divided into two groups: type I, which I just described; and type II, in which there are IgG antibodies to C1INH that inactivate C1INH. However, further research found that anti-C1INH antibodies are also found in type I. It has since been recognized that these are really different presentations of the same condition, with lymphoma cells depleting C1INH more readily. There have been documented instances in which achieving remission from lymphoma cured the associated AAE.

There are other types of angioedema that are difficult to classify. Idiopathic angioedema is the instance of three episodes in 6-12 months without a clear trigger or pathology. It is distinguished from hereditary angioedema by the shorter duration of symptoms. Further testing demonstrates normal levels and function of C1INH in these patients. This is sometimes called “idiopathic non-histaminergic AAE” to distinguish from an allergic process.

Type III HAE patients are sometimes positive for mutations in the Factor XII gene. However, in some patients, no mutation is found. All type III patients demonstrate normal level and function of C1INH. Type III patients experienced four attacks per year on average, with 42.9% having swelling in the airway. 85% had abdominal attacks, with some severe enough to result in emergency (though unnecessary) surgical procedures and ascites, free fluid in the abdomen.

In the patients with the Factor XII mutation, attacks were most likely to occur during high estrogen states, but were not exclusive to these periods. Initial attacks for this patient group usually occurred while on oral contraceptives or during pregnancy. However, men and children were also found to have Factor XII mutations. Initial attacks were less likely to affected by estrogen state in type III HAE with no FXII mutation or in idiopathic non-histaminergic angioedema. .

23% of type III patients exhibited elevated D-dimer levels outside of attack periods. Some also had extended clotting times. In the FXII mutated group, bruising was seen in a number of patients when swelling in the swollen portions of anatomy, but strictly in the skin. 27.9% of pregnancies in this group terminated in spontaneous miscarriage. Two births were extremely premature and one liveborn child died shortly after birth with no obvious cause of death.

References:

Zuraw, B. L., et al. A focused parameter update : Hereditary angioedema, acquired C1 inhibitor deficiency, and angiotensin-converting enzyme inhibitor-associated angioedema. J Allergy Clin Immunol 2013; 131(6); 1491-1493e25.

Kaplan AP, et al. Pathogenic mechanisms of bradykinin mediated diseases: dysregulation of an innate inflammation pathway. Adv Immunol 2014; 121:41-89.

Kaplan AP, et al. The plasma bradykinin-forming pathways and its interrelationships with complement. Mol Immunol 2010 Aug; 47(13):2161-9.

Firinu, Davide, et al. Characterization of patients with angioedema without wheals: the importance of F12 gene screening. Clinical Immunology (2015) 157, 239-248.

Csuka, Dorottya, et al. Activation of the ficolin-lectin pathway during attacks of hereditary angioedema. J Allergy Clin Immunol 134 (6) 1388-1393.e3.

Ohsawa, Isao, et al. Clinical manifestations, diagnosis, and treatment of hereditary angioedema: survey data from 94 physicians in Japan. Ann Allergy Asthma Immunol 114 (2015) 492-498.

Kajdacsi, E., et al. Endothelial cell activation during edematous attacks of hereditary angioedema types I and II. J Allergy Clin Immunol 133 (6); 1686-1691.

Triggianese, Paola, et al. The autoimmune side of hereditary angioedema: insights on the pathogenesis. Autoimmunity Reviews 2015 (ahead of press).

Madsen, Daniel Elenius, et al. C1-inhibitor polymers activate the FXII-dependent kallikrein-kinin system: implication for a role in hereditary angioedema. Biochimica and Biophysica Act 1850 (2015) 1336-1342.

Lasek-Bal, Anetta, et al. Hereditary angioedema with dominant cerebral symptoms finally leading to chronic disability. Clinical Neurology and Neurosurgery 135 (2015) 38-40.

 

 

 

Angioedema: Part 2

Patients with HAE may have normal bloodwork for routine tests. Blood counts, electrolytes and liver function tests are often unremarkable. Upon further testing, complement protein C4 is often low. This deficiency is most profound during attacks but often continues in interim periods. C3 is usually normal.

  • In HAE type I, C1 inhibitor (C1INH), C4 and C2 levels are low, while C1q is normal.
  • In HAE type II, C1INH is normal or marginally increased, C4 and C2 levels are low, and C1q is normal. C1INH functional tests yield low function.
  • In HAE type III, CIINH is normal and functions normally and C4 is sometimes normal. Mutation for Factor XII is sometimes found. This is still largely a diagnosis of exclusion based upon similar clinical presentation as the other two types.

Hereditary angioedema (HAE) attacks carry the risk of significant danger as airway constriction can lead to suffocation. More than half of HAE patients will experience laryngeal swelling at least once in their lifetime. Swells typically last 2-3 days and then resolve over the following two days. Antihistamines and steroids are ineffective in mitigating swelling of this type.

HAE attacks have many triggers in the same way mast cell disease does. HAE was originally termed angioneurotic disease because patients frequently had a strong emotional event that activated the disease. In women, swells may correspond to changes in circulatory estrogen – pregnancy, menopause, puberty, menses. Psychological stress is a well characterized trigger for HAE and patients are strongly urged to eliminate sources of stress wherever possible. ACE inhibitors are known to interfere with regulation of the pathway to produce bradykinin and should therefore by avoided.

The last few years have seen several medications for acute angioedema attacks come to market. Cinryze, Berinert and Ruconest are C1INH solutions for intravenous infusion that can be administered at home. Kalbitor is a kallikrein inhibitor that is formulated for subcutaneous injection. Firazyr blocks the bradykinin receptor and is also available for injection. It is universally agreed that these medications should be available on demand in the event of a swell as they have been shown to safely and effectively reduce the risk to life.

With the advent of these targeted medications, more outmoded treatments are start to be phased out. Previous treatment modalities include fresh frozen plasma for acute attacks or short term prophylaxis, anabolic steroids like anabolic steroids, such as danazol, and antifibrinolytic medications, such as tranexamic acid. These medications often had difficult side effects, but still see some use for prophylaxis to avoid swell episodes. For short term prophylaxis for procedures, 1000-2000U of C1INH, 2U of freshly frozen plasma or a week of high dose danazol can be used.

References:

Zuraw, B. L., et al. A focused parameter update : Hereditary angioedema, acquired C1 inhibitor deficiency, and angiotensin-converting enzyme inhibitor-associated angioedema. J Allergy Clin Immunol 2013; 131(6); 1491-1493e25.

Kaplan AP, et al. Pathogenic mechanisms of bradykinin mediated diseases: dysregulation of an innate inflammation pathway. Adv Immunol 2014; 121:41-89.

Kaplan AP, et al. The plasma bradykinin-forming pathways and its interrelationships with complement. Mol Immunol 2010 Aug; 47(13):2161-9.

Firinu, Davide, et al. Characterization of patients with angioedema without wheals: the importance of F12 gene screening. Clinical Immunology (2015) 157, 239-248.

Csuka, Dorottya, et al. Activation of the ficolin-lectin pathway during attacks of hereditary angioedema. J Allergy Clin Immunol 134 (6) 1388-1393.e3.

Ohsawa, Isao, et al. Clinical manifestations, diagnosis, and treatment of hereditary angioedema: survey data from 94 physicians in Japan. Ann Allergy Asthma Immunol 114 (2015) 492-498.

Kajdacsi, E., et al. Endothelial cell activation during edematous attacks of hereditary angioedema types I and II. J Allergy Clin Immunol 133 (6); 1686-1691.

Triggianese, Paola, et al. The autoimmune side of hereditary angioedema: insights on the pathogenesis. Autoimmunity Reviews 2015 (ahead of press).

Madsen, Daniel Elenius, et al. C1-inhibitor polymers activate the FXII-dependent kallikrein-kinin system: implication for a role in hereditary angioedema. Biochimica and Biophysica Act 1850 (2015) 1336-1342.

Lasek-Bal, Anetta, et al. Hereditary angioedema with dominant cerebral symptoms finally leading to chronic disability. Clinical Neurology and Neurosurgery 135 (2015) 38-40.

 

 

 

Administrative stuff

Hey, everyone –

Just a quick note about administrative stuff.

I am getting a lot of emails, FB messages and blog comments with questions from patients and providers.  This is fantastic!  I had GI surgery last month and am still in the process of recuperating.  I am responding to questions as I am able, but it will take me a bit to get through the backlog.  I appreciate your patience.

I am pretty accessible via the MastAttack Facebook group and have answered tons of questions there.  Additionally, there are lots of other people in that group who are veteran mast cell patients and/or subject matter experts on mast cell disease, dysautonomia or any number of other topics.  Feel free to join if you like.

I have had some questions about whether or not I take requests for posts.  I sure do.  If there is something you are dying to know about, just let me know.  My turnaround time is usually a few weeks.

Everyone seems to like my “master table” posts.  I have a bunch of these that I use for quick reference.  Since people find them helpful, I will upload some more.  These are living documents and will be updated as I find new information.  Likewise, if you have a helpful addition to a master table, let me know.

Some patients have told me that in the past few months, some of my posts are more “sciency” and it’s less easy to understand.  I agree that this is the case.  The purpose of these posts is for you to provide articles with references to providers, and for providers to be able to utilize this site as a source of easy to digest information.  I am considering doing some simplified posts on specific topics for patients.  I am not completely sure yet how I will do this.

MastAttack was started for the purpose of making information about these diseases accessible to the patients who live with them.  To that end, I will find a solution to make sure patients can come here and feel comfortable in their understanding.

Thanks for your patience while I get back up to speed.  I feel really fortunate to have such interested and thoughtful readers.  You guys are the best!

Lisa

Angioedema: Part 1

Hereditary angioedema (HAE) is a heritable blood disorder that causes episodes of protracted swelling, which can be life threatening. It has three subtypes, with two known to be caused by a mutation in the C1-INH (C1 inhibitor) gene.

HAE causes angioedema, a condition in which fluid leaves the bloodstream and passes into the space between the deep dermis and subcutaneous tissue. Swelling episodes can last for up to five days and swelling resolves between attacks. About 30% of HAE patients also have a rash similar to erythema marginatum, pink, slightly raised rings that don’t itch or wheal. HAE patients do not have hives or itching, an important distinction that allows diagnostic separation from chronic urticaria and angioedema

Swelling can occur in any region of the body, but face, GI tract, limbs, penis and scrotum are the most common. Angioedema of the tongue and pharynx can compromise the airway, as can edema of the larynx. In these patients, a tracheostomy may need to be placed.

Over 90% of patients suffer severe abdominal swells lasting 2-4 days. Abdominal pain, nausea, vomiting and diarrhea are common symptoms in this group. It is not unusual for doctors to assess the patient as having an “acute abdomen” in need of surgical intervention. Likewise, unnecessary surgery is often performed looking for the source of the swelling. These symptoms occur as a result of edema in the bowel wall, with complete or partial obstruction, sometimes causing ascites, or free fluid in the abdomen.

Angioedema seen in HAE patients is caused by excessive production of bradykinin, which is initiated by factor XII (also called Hageman factor). There are three types of HAE:

  • Patients with HAE type I (85% of cases) have too little C1 inhibitor which functions poorly.
  • Patients with type II (15% of cases) have normal levels of C1 inhibitor but it does not function correctly.
  • Patients with HAE type III have normal levels and function of C1 inhibitor, but have symptoms and treatment responses similar to those with types I and II. Current research indicates that these people sometimes have mutations in the gene for Factor XII, which is also involved in the production of bradykinin.

Bradykinin acts on B2 receptors to cause blood vessels to dilate, decreasing blood pressure. It also increases vessel permeability, allowing fluid and cells to leave the blood stream and become trapped in tissues, resulting in angioedema.

C1 inhibitor (C1INH) is a molecule with multiple regulatory functions. Its name derives from its relation to the complement protein C1, the activation of which is the initiating step in the classical pathway for the complement system, a mechanism for fighting infections. A side product of this pathway is the large scale production of complement proteins C3a and C5a, both of which can induce anaphylaxis. C1INH also regulates steps involving the formation of plasminogen and plasmin, which prevent the formation of blood clots.

C1INH also inhibits the molecule Factor XII, also called Hageman Factor. C1INH prevents Factor XII from activating itself, the first step in a pathway that produces bradykinin. Activation of Factor XII causes formation of molecules XIIa and XIIf. Factor XIIa induces conversion of prekallikrein to kallikrein, and kallikrein then acts on high molecular weight kininogen to release bradykinin. All of those steps are regulated by C1INH.

 

References:

Zuraw, B. L., et al. A focused parameter update : Hereditary angioedema, acquired C1 inhibitor deficiency, and angiotensin-converting enzyme inhibitor-associated angioedema. J Allergy Clin Immunol 2013; 131(6); 1491-1493e25.

Kaplan AP, et al. Pathogenic mechanisms of bradykinin mediated diseases: dysregulation of an innate inflammation pathway. Adv Immunol 2014; 121:41-89.

Kaplan AP, et al. The plasma bradykinin-forming pathways and its interrelationships with complement. Mol Immunol 2010 Aug; 47(13):2161-9.

Firinu, Davide, et al. Characterization of patients with angioedema without wheals: the importance of F12 gene screening. Clinical Immunology (2015) 157, 239-248.

Csuka, Dorottya, et al. Activation of the ficolin-lectin pathway during attacks of hereditary angioedema. J Allergy Clin Immunol 134 (6) 1388-1393.e3.

Ohsawa, Isao, et al. Clinical manifestations, diagnosis, and treatment of hereditary angioedema: survey data from 94 physicians in Japan. Ann Allergy Asthma Immunol 114 (2015) 492-498.

Kajdacsi, E., et al. Endothelial cell activation during edematous attacks of hereditary angioedema types I and II. J Allergy Clin Immunol 133 (6); 1686-1691.

Triggianese, Paola, et al. The autoimmune side of hereditary angioedema: insights on the pathogenesis. Autoimmunity Reviews 2015 (ahead of press).

Madsen, Daniel Elenius, et al. C1-inhibitor polymers activate the FXII-dependent kallikrein-kinin system: implication for a role in hereditary angioedema. Biochimica and Biophysica Act 1850 (2015) 1336-1342.

Lasek-Bal, Anetta, et al. Hereditary angioedema with dominant cerebral symptoms finally leading to chronic disability. Clinical Neurology and Neurosurgery 135 (2015) 38-40.

 

 

 

Activating the complement system: Classical, alternative and lectin pathways

The complement system is part of the innate immune system, meaning it does not “learn” over time by being exposed to organisms, and its behavior is the same throughout life. This system is made up of many small proteins that are manufactured in the liver and then released into the bloodstream. Importantly, these proteins are in an inactive state when they move out of the liver. To be active, these proteins have to be “cleaved” or have pieces of the molecule cut off. This is done by other proteins when specific signals are detected.

The complement system undergoes large scale amplification, meaning many, many proteins can be cleaved to fight infection from only one small signal. Once there are many complement proteins to help, they help to kill microbes by building a tunnel through the cell membrane. This tunnel is called the membrane attack complex (MAC).

There are three methods for activating the complement system, all of which involve several steps and several molecules.  It is crucial that these complements are present in the correct ratio or it can contribute to inflammation and disease.

The classical pathway is activated in one of three ways:

  1. Activation:
  • An antibody binds to the outside of microbe. This can be done by certain types of IgG (but not IgG4) or IgM.
  • The enzyme C1 can also bind to the surface of some microbes.
  • C-reactive protein can also activate the classical system by binding to some microbial products.
  1. In the blood, C1 is actually made up of three small parts called subunits: C1q, C1r and C1s. The C1q binds to the antibody on the surface of the microbe. This activates the subunits.
  2. C1s cleaves C4 into two pieces. C4b binds to the cell surface of the microbes. C4a has no function here and is broken down after being released.
  3. C1s cleaves C2 into two pieces. C2b binds to C4b, which is bound to the cell surface. C2a has no function here and is broken down after being released.
  4. When C4b and C2b are bound together, they are called C3 convertase and they perform the special function of cleaves C3. C3 is cleaved into two pieces.
  5. C3b binds to various places on the cell surface. Macrophages and neutrophils (immune cells) can bind to C3b. When macrophages bind to C3b, it may then phagocytose (or eat) the microbe. C3b can also bind to C5, which allows it to be cleaved by C3/C5 convertase.
  6. C3a is an anaphylatoxin. (I have written a previous detailed post on this). It can trigger basophils and mast cells to degranulate.
  7. C5 is cleaved by C3/C5 convertase. This release C5a and C5b.
  8. C5a is a very strong anaphylatoxin and also attracts neutrophils to fight infections.
  9. C5b is the anchor for the membrane attack complex. C6, C7, C8 and several molecules of C9 form a long line on molecules that pokes a whole in the membrane of the microbe. If the membrane is broken, water will rush into the cell and the cell will not function correctly. This results in cell death.

The alternative pathway is activated as follows:

  1. C3 can turn itself into the molecule C3b. This is spontaneous and does not require any other molecules. C3b is short lived under normal circumstances.
  2. If a microbe is nearby, C3b will bind to a molecule on the microbial surface called Factor B.
  3. C3b and Factor B bound together are a different kind of C3 convertase than the one described for classical pathway. This C3 convertase cleaves other molecules.
  4. C3b-Factor B, a C3 convertase, cleaves a molecule of C3.
  5. The liberated molecule of C3b binds to C3b-Factor B-C3b. This is a C5 convertase, which starts the membrane attack complex.
  6. While the MAC is being made, this C5 convertase is still cleaving C3 to release large amounts of C3b.

The lectin pathway is activated as follows:

  1. MBL and ficolin bind to microbial surfaces.
  2. This activates the molecule MASP-2.
  3. MASP-2 cleaves C4 and C2, forming a grouping of molecules called the terminal complement complex (TCC).
  4. C1s cleaves C2 into two pieces. C2b binds to C4b, which is bound to the cell surface. C2a has no function here and is broken down after being released.
  5. When C4b and C2b are bound together, they are called C3 convertase and they perform the special function of cleaves C3. C3 is cleaved into two pieces.
  6. C3b binds to various places on the cell surface. Macrophages and neutrophils (immune cells) can bind to C3b. When macrophages bind to C3b, it may then phagocytose (or eat) the microbe. C3b can also bind to C5, which allows it to be cleaved by C3/C5 convertase.
  7. C3a is an anaphylatoxin. (I have written a previous detailed post on this). It can trigger basophils and mast cells to degranulate.
  8. C5 is cleaved by C3/C5 convertase. This release C5a and C5b.
  9. C5a is a very strong anaphylatoxin and also attracts neutrophils to fight infections.
  10. C5b is the anchor for the membrane attack complex. C6, C7, C8 and several molecules of C9 form a long line on molecules that pokes a whole in the membrane of the microbe. If the membrane is broken, water will rush into the cell and the cell will not function correctly. This results in cell death.

 

Some molecules control the complement system so that the amplification does not cause problems.

  • Factor H controls the alternative pathway. It helps to degrade the C3b-Factor B-C3b complex.
  • Factor I converts C3b to an inactive form.
  • C1INH (C1 inhibitor) binds to activated C1r and C1s, making them inactive. This happens quickly, so there is only a brief time before C1INH binds to C1r or C1s during which they can cleave C4 and C2.

 

 

 

Master table of de novo mast cell mediators

 

Mediator Symptoms Pathophysiology
b-FGF (basic fibroblast growth factor) Angiogenesis, proliferation, wound healing, binds heparin
GM-CSF (granulocyte macrophage colony stimulating factor) Rheumatoid arthritis Induces stem cells to make granulocytes and monocycles
IL-1a Fever, insulin resistance, inflammatory pain Activates TNFa, stimulates production of PGE2, nitric oxide, IL-8 and other chemokines
IL-1b Pain, hypersensitivity Autoinflammatory syndromes, regulates cell proliferation, differentiation and death, induces COX2 activity to produce inflammatory molecules
IL-2 Itchiness, psoriasis Regulates T cell differentiation
IL-3 Drives differentiation of several cell types, including mast cells, and proliferation
IL-4 Airway inflammation, allergic asthma Regulates T cell differentiation
IL-5 Eosinophilic allergic disease Activates eosinophils, stimulates proliferation of B cells and antibody secretion, heavily involved in eosinophilic allergic disease
IL-6 Fever, acute phase inflammation, osteoporosis Inhibits TNFa and IL-1, stimulates bone resorption, reduces inflammation in muscle during exercise
IL-9 Asthma, bronchial hypersensitivity Increases cell proliferation and impedes apoptosis of hematopoietic cells
IL-10 Regulates the JAK-STAT pathway, interferes with production of interferons and TNFa.   Exercise increases levels of IL-10
IL-13 Airway disease, goblet cell metaplasia, oversecretion of mucus Induces IgE release from B cells, links allergic inflammation to non-immune cells
IL-16 Allergic asthma, rheumatoid arthritis, Crohn’s disease Attracts activated T cells to inflamed spaces,
IL-18 Linked to several autoimmune and inflammatory conditions, including Hashimoto’s thyroiditis Induces release of interferon-g, causes severe inflammatory reactions
Interferon-a Flu like symptoms, malaise, muscle soreness, fever, sore throat, nausea Inhibition of mast cell growth and activity
Interferon-b Flu like symptoms, malaise, muscle soreness, fever, sore throat, nausea Inhibition of mast cell growth and activity
Interferon-g Granuloma formation, chronic asthma Induces production of nitric oxide, IgG2a and IgG3 from B cells, increases production of histamine, airway reactivity and inflammation
Leukotriene B4 Mucus secretion, bronchoconstriction, vascular instability, pain Draws white cells to site of inflammation
Leukotriene C4 Mucus secretion, bronchoconstriction, vascular instability, pain Draws white cells to site of inflammation
MCP-1 Neuroinflammation, diseases of neuronal degeneration, glomerulonephritis Draws white blood cells to inflamed spaces,
MIF (macrophage migration inhibitory factor) Regulate acute immune response, release triggered by steroids
MIP-1a (macrophage inflammatory protein) Fibrosis Activates granulocytes, nduces release of IL-1, IL-6 and TNFa
Neurotrophin-3 Nerve growth factor
NGF (nerve growth factor) Regulates survival and growth of nerve cells, suppresses inflammation
Nitric oxide Bruising, hematoma formation, excessive bleeding Vasodilation, inhibition of platelet aggregation
PDGF (platelet derived growth factor) Platelet growth factor, growth of blood vessels, wound healing
Platelet activating factor Constriction of airway; urticaria; pain Platelet activation and aggregation, vasodilation
Prostaglandin D2 Flushing, mucus secretion, bronchoconstriction, vascular instability, mixed organic brain syndrome, nausea, abdominal pain, neuropsych symptoms, nerve pain Inflammation, pain, bronchoconstriction
Prostaglandin E2 Muscle contractions, cough Draws white blood cells to site of inflammation
RANTES (CCL5) Osteoarthritis Attracts white cells to inflamed spaces, causes proliferation of some white cells
SCF (stem cell factor) Regulates mast cell life cycle, induces histamine release
TGFb (transforming growth factor beta) Bronchial asthma, heart disease, lung fibrosis, telangiectasia, Marfan syndrome, vascular Ehlers syndrome syndrome Regulates vascular and connective tissues
TNFa (tumor necrosis factor) Fever, weight loss, fatigue Regulates death of cells and acute inflammation
VEGF (vascular endothelial growth factor) Bronchial asthma, diabetes Angiogenesis, draws white cells to inflamed spaces, vasodilation

 

 

Master table of stored mast cell mediators

Mediator Symptoms Pathophysiology
Angiogenin Tissue damage Formation of new blood vessels, degradation of basement membrane and local matrix
Arylsulfatases Breaks down molecules to produce building blocks for nerve and muscle cells
Bradykinin Angioedema, swelling of airway, swelling of GI tract, inflammation, pain, hypotension Vasodilation, induces release of nitric oxide and prostacyclin
Carboxypeptidase A Muscle damage Tissue remodeling
Cathepsin G Pain, muscle damage Converts angiotensin I to II, activates TGF-b, muscle damage, pain, fibrosis, activates platelets, vasodilation
Chondroitin sulfate Cartilage synthesis
Chymase Cardiac arrhythmia, hypertension, myocardial infarction Tissue remodeling, conversion of angiotensin I to II, cleaves lipoproteins, activates TGF-b, tissue damage, pain, fibrosis
Corticotropin-releasing hormone Dysregulation has wide reaching and severe effects Stimulates secretion of ACTH to form cortisol and steroids
Endorphins Numbness Pain relief
Endothelin Hypertension, cardiac hypertrophy, type II diabetes, Hirschsprung disease Vasoconstriction
Eotaxin (CCL11) Cognitive deficits Attracts eosinophils, decreases nerve growth
Heparin Hematoma formation, bruising, prolonged bleeding post-biopsy, gum bleeding, epistaxis, GI bleed, conjunctival bleeding, bleeding ulcers Cofactor for nerve growth factor, anticoagulant, prevents platelet aggregation, angiogenesis
Histamine Headache, hypotension, pruritis, urticaria, angioedema, diarrhea, anaphylaxis Vasodilation of vessels, vasoconstriction of atherosclerotic coronary arteries, action of endothelium, formation of new blood vessels cell proliferation, pain
Hyaluronic acid Degradation contributes to skin damage Tissue repair, cartilage synthesis, activation of white blood cells
IL-8 (CXCL8) Mast cell degranulation Attracts white blood cells (mostly neutrophils) to site of infection, activates mast cells, promotes degranulation
Kininogenases Angioedema, pain, low blood pressure Synthesis of bradykinin
Leptin Obesity Regulates food intake
Matrix metalloproteinases Irregular menses (MMP-2) Tissue damage, modification of cytokines and chemokines (modifies molecules to make them useful)
MCP-1 (CCL2) Nerve pain Attracts white blood cells to site of injury or infection, neuroinflammation, infiltration of monocytes (seen in some autoimmune diseases)
MCP-3 (CCL7) Increases activity of white blood cells in inflamed spaces
MCP-4 (CCL13) Shortness of breath, tightness of airway, cough Attracts white blood cells to inflamed spaces, induces mast cell release of TNFa and IL-1, asthma symptoms
Phospholipase A2 Vascular inflammation, acute coronary syndrome Generates precursor molecule for prostaglandins and leukotrienes
RANTES (CCL5) Osteoarthritis Attracts white cells to inflamed spaces, causes proliferation of some white cells
Renin Cardiac arrhythmias, myocardial infarction, blood pressure abnormalities Angiotensin synthesis, controls volume of blood plasma,lymph and interstitial fluid, regulates blood pressure
Serotonin/5-HT Nausea, vomiting, diarrhea, headache, GI pain Vasoconstriction, pain
Somatostatin Low stomach acid symptoms, low blood sugar Regulates endocrine system, cell growth and nerve signals, inhibits release of glucagon and insulin, decreases release of gastrin, secretin and histamine
Substance P Neurologic pain, inflammation, nausea, vomiting, mood disorders, anxiety Transmits sensory nerve signals, including pain, mood disorders, stress perception, nerve growth and respiration
Tissue plasminogen activator Blood clots Activates plasminogen, clotting
Tryptase Hematoma formation, bruising, prolonged bleeding post-biopsy, gum bleeding, epistaxis, GI bleed, conjunctival bleeding, bleeding ulcers; inflammation Activation of endothelium, triggers smooth muscle proliferation, activates degradation of fibrinogen, activates MMP molecules,tissue damage, activation of PAR, inflammation, pain
Urocortin Increased appetite when stressed, inflammation, low blood pressure Vasodilation, increases coronary blood flow
Vasoactive intestinal peptide Decreased absorption, low blood pressure, low stomach acid symptoms Vasodilation, mast cell activation, lowers blood pressure, relaxes muscles of trachea, stomach and gall bladder, inhibits gastric acid secretion, inhibits absorption
VEGF Diseases of blood vessels Formation of new blood vessels, vasodilation and permeability of smaller vessels

Winding in the light

I have a wound on my abdomen, a literal open wound where my stoma was. Every night I undress it, removing long thin strips of gauze before replacing them with clean packing, manipulating the tendrils with sterilized scissors. It is graphic, visceral. But I prefer to do it myself. I prefer this active stewardship of my body.

It is healing, closing up along the seams that have formed on my skin, one on each side. I am participating in the act of healing my body. Soon the line will be continuous, all the tissue underneath knitted together. Just a line that keeps a secret, like lips sewn shut. No one will ever look at this scar and know I had an ostomy until I tell them.

My GI tract is trying to figure out how to work with this new continuity. It hurts. It feels like everything holding my abdomen together on the left side is trying to give out. I am starting the very slow and arduous process of regaining strength and routine. It feels like a lot on some days. Today it feels like a lot.

But two years ago this was unfathomable. Even six months ago, I thought I knew pretty well the path my life would take it, and it was a short road, a straight line to pain and anaphylaxis and liquids and soft solids forever. I still see that road, but it is longer and it winds its way more into the light.

I don’t believe anymore that there is any fear that is so wide and so deep that you cannot meet it. I just don’t believe it.

Deconditioning, orthostatic intolerance, exercise and chronic illness – Part 7

A number of studies have investigated whether loading with intravenous hydration solutions (saline, etc) or with a volume expander such as dextran can ameliorate symptoms associated with deconditioning. These studies have found that volume expansion (also called fluid or volume loading) can improve a number of symptoms in deconditioned patients, but does not improve exercise capacity. Multiple studies have found the best effects from intravenous saline in conjunction with exercise.

Shibata investigated whether orthostatic intolerance could be mitigated following bed rest with exercise and/or fluid loading (Shibata 2010). This study found that OI could be dextran solution (IV fluids) given after twenty days of bed rest was insufficient to control OI symptoms, but that it was successful when used in conjunction with a daily exercise program. This finding was important, as it indicated that low blood volume was not the exclusive factor in orthostatic intolerance.

Figueroa et al looked at the relationship between blood volume and exercise capacity in POTS patients (Figueroa 2014). They found that acute volume loading with IV saline reduces heart rate and improves orthostatic tolerance and other symptoms in POTS patients. Importantly, IV saline significantly increased the stroke volume, cardiac output and reduced systemic vascular resistance. However, IV saline did not affect peak exercise capacity or improve cardiovascular markers during exercise. So while IV saline does help symptoms in these deconditioned patients, it does not improve exercise capacity. The author notes that for this purpose, acute infusion may not be sufficient and may need to undergone chronically to see benefits on exercise physiology.

Whole body heating is known to increase cardiac output, constrict the blood vessels in the abdominal cavities, increase sympathetic nerve activity in the muscles and decrease vascular resistance in the skin. Taken together, these factors stress the regulatory mechanism of the cardiovascular system. One study (Keller 2009) found that acute expansion of blood volume (with dextran) completely mitigated the impact of heat stress on orthostatic tolerance. In short, receiving an infusion that increased the blood volume allowed the cardiovascular system to function properly in the face of a known stressor.

One study looked at the effect of fluid loading on orthostatic intolerance and blood flow in the brain (Jeong 2012). They found that following bed rest, volume loading alone prevented larger reductions in cerebral blood flow, but did not prevent orthostatic intolerance. Exercise and volume loading prevented orthostatic intolerance but did not affect cerebral blood flow. Importantly, aerobic or resistance exercise before bed rest did not prevent development of decompensation.

A 2000 paper notes that POTS symptom scores improved significantly following administration of IV saline (Gordon 2000). Additionally, a 2013 study evaluated the frequency and characterization of “brain fog”, a common term for the cognitive deficits associated with this (and other) conditions (Joyner 2013). 86% (56/66) of patients reported that IV saline was the most effective treatment for brain fog.

In summary, bolus IV fluids or volume expanders have been found to improve a number of symptoms in deconditioned patients, although they have not been found to improve exercise capacity. For this metric, a graded exercise program is recommended. 

(Author’s note: I have recently been made aware that the data supporting use of graded exercise for chronic fatigue patients was hugely flawed. I retract this statement at this time. For details on this topic, please refer to this Lancet article: http://www.thelancet.com/journals/lancet/article/PIIS0140-6736(11)60686-7/fulltext)

A 2008 paper compared POTS and deconditioning (Joyner 2008). The author pointed out that a number of parallels existed between the physiological changes seen in POTS patients and those seen in deconditioned patients. Additionally, he made note of the parallels between POTS, chronic fatigue syndrome and fibromyalgia and the fact that exercise training had seen benefits in all of them. Given the significant relationship between mast cell disease and POTS, and the large overlap in CFS, fibromyalgia and mast cell populations, it is a comfortable assumption that an effective treatment modality for CFS, POTS and fibromyalgia may also be effective for mast cell disease. It is my belief that this is the basis for the frequently discussed finding of mast cell patients that intravenous fluids ameliorate a number of symptoms.

Furthermore, there are special considerations for mast cell disease that make intravenous fluids likely to cause a positive change in symptom profile. The first is that mast cell degranulation can induce systemic effects on arterial tone, hypotension and vasodilation (Willingham 2009). The next is that hypotension is characteristic of systemic mastocytosis, and that hypotension and syncope may occur due to cerebral hypoperfusion (Ozdemir 2010). Lastly, it is well known that mast cell mediators, including histamine, serotonin and tryptase, can induce capillary leakage leading leading to edema, and that they can increase vascular permeability (He 1997). Taken together, these points indicate that a mast cell patient may lose volume from the bloodstream into the surrounding tissues, which can exacerbate an already existing tendency toward hypotension, in turn made worse by orthostatic intolerance.

Fluid loading in the form of intravenous fluids may decrease symptoms in mast cell patients due to deconditioning, orthostatic intolerance and the capillary leakage often seen as a result of mast cell disease, which is especially present following mast cell attacks and anaphylaxis.

 

References:

Gordon VM., et al. Hemodynamic and symptomatic effects of acute interventions on tilt in patients with postural tachycardia syndrome. Clin Auton Res. 2000 Feb; 10(1): 29-33.

Ross, Amanda J., et al. What is brain fog? An evaluation of the symptom in postural tachycardia syndrome. Clin Auton Res 2013 Dec; 23(6): 305-311.

Raj, Satish R., et al. Postural orthostatic tachycardia syndrome (POTS). Circulation 2013; 127: 2336-2342.

Rocío A. Figueroa, et al. Acute volume loading and exercise capacity in postural tachycardia syndrome. J Appl Physiol 117:663-668, 2014.

He, Shaoheng, Walls, Andrew F. Mast cell activation may be all that is sufficient and necessary for the rapid development of microvascular leakage and tissue edema. European Journal of Pharmacology 1997; 328(1): 89-97.

Ozdemir, D., et al. Hypotension, syncope and fever in systemic mastocytosis without skin infiltration and rapid response to corticosteroid and cyclosporine: a case report. Case Reports in Medicine, Volume 2010 (2010), Article ID 782595.

Willingham DL, et al. Unexplained and prolonged perioperative hypotension after orthotopic liver transplantation: undiagnosed systemic mastocytosis. Liver Transpl 2009 Jul; 15(7): 701-8.

Keller, David M., et al. Acute volume expansion preserves orthostatic tolerance during whole body heat stress in humans. J Physiol 2009 Mar; 587(5): 1131-1139.

Sung-Moon Jeong , Shigeki Shibata , Benjamin D. Levine , Rong Zhang. Exercise plus volume loading prevents orthostatic intolerance but not reduction in cerebral blood flow velocity after bed rest. American Journal of Physiology – Heart and Circulatory Physiology 2012 Vol. 302 no. 2.

Shizue Masuki , John H. Eisenach , William G. Schrage , Christopher P. Johnson , Niki M. Dietz , Brad W. Wilkins , Paola Sandroni , Phillip A. Low , Michael J. Joyner. Reduced stroke volume during exercise in postural tachycardia syndrome. Journal of Applied Physiology 2007 Vol. 103 no. 4, 1128-1135.

 

 

 

 

 

Do all mast cell patients need central lines? No. But some do.

A newer patient asked a couple of days if everyone with mast cell disease needs a PICC line, Broviac/Hickman or port for IV access. The answer is no, but I think we should talk about this a bit.

Central lines are usually given for people who need chemo or long term IV treatmet. These lines are not really designed to be left in your body forever, even ports. They generally are pulled once treatment is done, although ports can be left in for years as long as they are flushed monthly.

In my experience, mast cell patients get central lines for a few reasons:

  1. They have very poor IV access, so poor that it could delay treatment in an emergency (anaphylaxis).
  2. They get regular IV medications (this is not very common, although it’s hard to tell in this group).
  3. They regularly take IV medication that can damage veins if given frequently in peripheral veins (like Benadryl).
  4. They get them for IV hydration (it is not recommended to get a central line just for IV hydration, however some people do get them).

In the groups, it seems like there are so many patients who have these lines. Please keep in mind that those with more disabling disease are the most likely to be present in those forums. This group often also has other diagnoses for which central lines may be beneficial. On the other hand, the other group that is quite visible is the rookies. So the new patients see this very severe face on a disease which is quite manageable for many. You are seeing a subset of the population. Central lines in the mast cell community are not as common as it seems.

Regarding IV hydration, there are a few reasons why people receive this. Some of us vomit frequently and so fluids are difficult to get into us orally. Some of us have POTS or dysautonomia and have low blood volume, so the IV hydration stabilizes our blood pressure and heart rate. Some of us third space badly, and oral fluids end up in the wrong place.

This patient asked if they could just drink fluids. The answer is absolutely yes. If you can keep oral fluids down and are functioning, then I would do that. Receiving regular IV fluids can help with some symptoms, but there is no reason they need to be delivered through a central line. I used to get IV fluids at the infusion center with a new IV everytime. It is a pain but it’s not awful.

In an acute situation, IV fluids can be very helpful to mast cell patients. Long term, you need to be monitored properly as it can affect your electrolytes and for some this may raise kidney concerns. I would not get IV fluids based simply upon “feeling dehydrated”. If you “feel dehydrated” and also your blood pressure is wacky and you can’t keep down oral fluids, I think that then regular IV hydration might be useful.

I know it is frustrating to feel that you are not doing as well as you used to, but if you have mast cell disease, it is very possible you never will again, even with IV fluids. I am sorry, but that is the reality. You need to adapt to the level of ability you can manage currently.  Get some stability and things will improve.

If you and your doctor feel that IV hydration is appropriate, I would try it outpatient for a few weeks. If they then feel you need to do it at home, placing a PICC line is a good place to start. If you have a problem with the PICC line, it can be pulled without much trouble. The other lines are implanted and require surgery to remove them. The risk of bloodstream infections from central lines is real and these are very serious situations with long term effects.

Mast cell patients also run the risk of reacting to the materials used to make the line. They can also react to the maintenance of the line, such as flushing, use of heparin and alcohol swabs. This is a real problem for some people. So any time you can avoid an indwelling line long term, that is the better option.

Lastly, central lines require maintenance so you need to be sure that if your doctor wants to order one, they will also order the solutions and nursing care needed to keep you safe.