lymphfantastic

Die Suche geht weiter- The search goes on


4 Kommentare

Collaboration between two Stanford labs has resulted in the discovery of a molecular cause for lymphedema the first possible drug treatment for it

Study finds first possible drug treatment for lymphedema

Collaboration between two Stanford labs has resulted in the discovery of a molecular cause for lymphedema and the first possible drug treatment for it.

Woman standing in front of her garden and home

Tracey Campbell suffers from lymphedema and is participating in a clinical trial of a drug to determine whether it can treat the painful condition.
Mark Williams

Tracey Campbell has lived for seven years with lymphedema, a chronic condition that causes unsightly swelling in her left leg.

The disease, which stems from a damaged lymphatic system, can lead to infections, disfigurement, debilitating pain and disability. There is no cure. The only available treatment is to wear compression garments or use massage to suppress the swelling, which can occur throughout the body in some cases. Campbell — who had two quarts of excess water in her left leg by the time she was diagnosed — has for years worn restrictive garments 24 hours a day and has spent an hour each night massaging the lymph fluid out of her leg.

Lymphedema is uncomfortable, exhausting and dangerous if left uncontrolled. As many as 10 million Americans and hundreds of millions of people worldwide suffer from the condition, many from the after-effects of cancer therapy treatments.

“There’s this extra layer of emotional burden,” said Campbell, who added that she has to be constantly vigilant to protect against infection. “All you want to be is normal.”

Now there’s new hope for a possible pharmaceutical treatment for patients like Campbell. A study led by scientists at the Stanford University School of Medicine has uncovered for the first time the molecular mechanism responsible for triggering lymphedema, as well as a drug with the potential for inhibiting that process.

The study was published May 10 in Science Translational Medicine.

“We figured out that the biology behind what has been historically deemed the irreversible process of lymphedema is, in fact, reversible if you can turn the molecular machinery around,” said Stanley Rockson, MD, professor of cardiovascular medicine and the Allan and Tina Neill Professor of Lymphatic Research and Medicine at Stanford. Rockson shares senior authorship of the study with Mark Nicolls, MD, professor of pulmonary and critical care medicine. Stanford research scientists Wen “Amy” Tian, PhD, and Xinguo Jiang, MD, PhD, share lead authorship of the study and are also affiliated with the Veterans Affairs Palo Alto Health Care System.

‘Fundamental new discovery’

“This is a fundamental new discovery,” said Nicolls, who is also a researcher at the VA Palo Alto.

Stanley Rockson

Stanley Rockson

The researchers found that the buildup of lymph fluid is actually an inflammatory response within the tissue of the skin, not merely a “plumbing” problem within the lymphatic system, as previously thought.

Working in the lab, scientists discovered that a naturally occurring inflammatory substance known as leukotriene B4, or LTB4, is elevated in both animal models of lymphedema and in humans with the disease, and that at elevated levels it causes tissue inflammation and impaired lymphatic function.

Further research in mice showed that by using pharmacological agents to target LTB4, scientists were able to induce lymphatic repair and reversal of the disease processes.

“There is currently no drug treatment for lymphedema,” Tian said. Based on results of the study, the drug bestatin, which is not approved for use in the United States but which has been used for decades in Japan to treat cancer, was found to work well as an LTB4 inhibitor, with no side effects, she said.

Based on the research, bestatin (also known as ubenimex), is being tested in a clinical trial that started in May 2016 — known as ULTRA — as a treatment for secondary lymphedema, which occurs because of damage to the lymphatic system from surgery, radiation therapy, trauma or infection. Primary lymphedema, on the other hand, is hereditary. The results of the research pertain to both types.

Rockson is principal investigator for this multisite phase-2 clinical trial.

“The cool thing about this story — which you almost never see — is that a clinical trial testing the therapy has already started before the basic research was even published,” Nicolls said. “This is the first pharmaceutical company-sponsored trial for a medical treatment of lymphedema, a condition that affects millions.”

Nicolls and Tian are co-founders of Eiccose LLC. Eiccose is now part of Eiger BioPharmaceuticals, which gets the drug from Nippon Kayaku in Japan. Eiger is sponsoring the clinical trial. Nicolls and Rockson are both scientific advisers to the company.

Two labs, two diseases

The study, which got underway about four years ago, began somewhat uniquely as a collaboration between two labs that were studying two completely different diseases. At the time, the Nicolls lab, where Tian works, was studying pulmonary hypertension. The Rockson lab was conducting lymphedema research.

Mark Nicolls

Mark Nicolls

The two teams met through SPARK, a Stanford program designed to help scientists translate biomedical research into treatments for patients.

“I was in a privileged position of seeing two faculty conducting important research and recognizing the possible link in causality,” said Kevin Grimes, MD, associate professor of chemical and systems biology and co-founder of SPARK. “It occurred to me that both diseases affected vascular tissues and had strong inflammatory components.”

“He blind-dated us,” Nicolls said. “When Amy Tian and I looked at the data from Stan’s research, Amy said, ‘It looks like it could be the same molecular process.’”

“It was an arranged marriage between us and Stan which worked out great,” Tian said.

At the time, Rockson had begun to suspect that lymphedema was an inflammatory disease. This led to his team’s discovery that the anti-inflammatory drug ketoprofen successfully helped to relieve lymphedema symptoms, although it wasn’t a perfect drug; side effects were a concern, and it remained unclear how the drug worked at the molecular level.

Meanwhile, the Nicolls lab had discovered that LTB4 was part of the cycle of inflammation and injury that keeps pulmonary hypertension progressing. When researchers blocked LTB4 in rats with the disease, their symptoms lessened and blood vessels became less clogged, lowering blood pressure in the lungs.

“When we became aware of Mark’s work, we began to realize that we were both possibly dealing with the activation of steps downstream of the 5-LO [5-lipoxygenase] pathway,” Rockson said. “This became intriguing and formed the basis of our relationship.”

Joining forces

The two teams joined forces to figure out the mechanism that triggered lymphedema, hopefully revealing a target for drug treatment in humans. After determining that ketoprofen was primarily working on the 5-LO pathway, the researchers began blocking the various endpoint pathways after 5-LO activation in mouse models of lymphedema, Rockson said.

“It turned out that, in fact, we were both dealing with the same branch, which is LTB4,” Rockson said.

When all of the sudden one of your limbs begins to swell, you want to understand what the heck is going on.

“So now it became clear we really were dealing with a very similar biological process in two different diseases,” he said. “Because of Mark’s work in pulmonary hypertension, we knew that we had an ideal form of therapy that we could try in lymphedema as well.”

The Nicolls lab had used the drug bestatin, which blocks the enzyme that generates LTB4, to reverse pulmonary hypertension disease processes. When researchers tested bestatin in the mouse lymphedema model, it worked to reverse symptoms of that disease.

“I’m still in awe,” Rockson said. “There are few situations where you take a problem at the bedside, and go into the lab, and then take discoveries back to the bedside. It’s amazingly gratifying.”

Campbell, who is now participating in the double-blinded, placebo-controlled bestatin trial at Stanford, remains hopeful.

“When all of the sudden one of your limbs begins to swell, you want to understand what the heck is going on,” she said. “It’s a tough condition that few people seem to care about, even though millions and millions suffer with it. We’re hoping for something that gives some relief.”

Other Stanford authors are research associate Jeanna Kim; former medical students Adrian Begaye, MD, and Abdullah Feroze, MD; Roham Zamanian, MD, associate professor of medicine and director of the Adult Pulmonary Hypertension Service; Gundeep Dhillon, MD, associate professor of medicine and medical director of the Stanford Lung Transplant Program; and research assistants Eric Shuffle and Allen Tu. Shuffle and Tu are affiliated with both Stanford and the VA Palo Alto.

Researchers at Georgia Institute of Technology, Virginia Commonwealth University, the University of Michigan Health Systems and the University of Illinois at Chicago are also co-authors.

Eiger BioPharmaceuticals has licensed intellectual property developed by Tian, Rockson, Jiang, Kim and Nicolls involving the targeting of LTB4 for the treatment of lymphedema.

Stanford’s Department of Medicine supported the work.



Stanford Medicine integrates research, medical education and health care at its three institutions – Stanford University School of Medicine, Stanford Health Care (formerly Stanford Hospital & Clinics), and Lucile Packard Children’s Hospital Stanford. For more information, please visit the Office of Communication & Public Affairs site at http://mednews.stanford.edu.

 

 

http://med.stanford.edu/news/all-news/2017/05/study-finds-first-possible-drug-treatment-for-lymphedema.html

Advertisements


Hinterlasse einen Kommentar

Fighting cancer with immunotherapy: Signaling molecule causes regression of blood vessels

Immunotherapy with T-cells offers great hope to people suffering from cancer. Some initial successes have already been made in treating blood cancer, but treating solid tumors remains a major challenge. The signaling molecule interferon gamma, which is produced by T-cells, plays a key role in the therapy. It cuts off the blood supply to tumors, as a new study reveals.

A microscopic image of tumor tissue under the influence of TNF (left) and IFN- ? (right). Red blood cells are pictured in a magenta color. TNF bursts the blood vessels and releases large amounts of blood cells, whereas IFN-? lets vessels retreat.
Credit: Christian Friese / MDC

Immunotherapy with T-cells offers great hope to people suffering from cancer. Some initial successes have already been made in treating blood cancer, but treating solid tumors remains a major challenge. The signaling molecule interferon gamma, which is produced by T-cells, plays a key role in the therapy. It cuts off the blood supply to tumors, as a new study in the journal Nature reveals.

The immune system is the body’s most powerful weapon against diseases. So what if it were possible to use the immune system to fight cancer? For a long time now, researchers have been trying to do just that — for example, by employing a special kind of immune cell called T-cells. They are „special mobile forces“ that — after undergoing training — patrol the body, and can seek out and kill cancer cells. This strategy has been successful in initial clinical trials — but mostly just in the treatment of cancers that do not form tumors, such as blood cancer.

Good at fighting blood cancer, but not so effective against solid tumors

Large solid tumors, on the other hand, sometimes pose big problems for T-cells. Though adept at targeting cancer cells swimming in the bloodstream, they have difficulty attacking compact tumors. The tumor weakens the aggressors through the delivery of inhibiting signals.

The scientists working with Dr. Thomas Kammertöns, Prof. Thomas Blankenstein, Prof. Hans Schreiber and Christian Friese are searching for solutions with their research team at Charité — Universitätsmedizin Berlin, Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin Institute of Health (BIH) and the Einstein Foundation.

In a study published in the journal Nature, they investigated how the signaling molecules of T-cells affect the immediate tumor environment, which includes the connective tissue as well as the blood vessels that supply the tumor.

T-cells produce not only tumor necrosis factor (TNF) but also the molecule interferon gamma (IFN-γ). Until now, however, there has been little understanding about how IFN-γ really works. „We knew that IFN-γ attacks cancer cells via the tumor microenvironment,“ says Kammertöns. „We now wanted to find out exactly which cells are targeted by the signaling molecules.“

Blood vessel regression is induced

The researchers generated genetically modified mice and used a clinically relevant cancer model. This included animals in which only blood vessel cells were susceptible to the signaling molecule.

In this mouse model IFN-γ pruned back the blood vessels in the tumors, thus shutting down the supply of oxygen and nutrients and killing the tumors. The researchers were able to observe this process microscopically in living mice in fine detail. They found that the blood vessel cells alone responded to the signaling molecule. When the researchers targeted other types of cells with IFN-γ, the tumors continued their growth.

These findings provided an explanation for the molecule’s powerful properties, which were already well known. „IFN-γ is one of the most important weapons in the T-cells‘ arsenal,“ says Thomas Kammertöns.

Thomas Blankenstein, lead investigator of the study, says: „The two together — IFN-γ and tumor necrosis factor — are a powerful team. TNF bursts tumor blood vessels, thus opening up the tissue, while IFN-γ cuts off the blood supply and keeps the tumor at bay over the long term.“

Optimizing T-cell therapy

The study offered the researchers clues on how to improve T-cell therapy for solid cancer tumors. Thomas Blankenstein explains: „We want to understand exactly how T-cells target tumors. Destroying a tumor’s infrastructure is probably more effective than killing individual cancer cells.“

„Our findings are significant beyond tumor therapy,“ says Thomas Kammertöns. „Interestingly, the mechanism used by IFN-γ to eliminate solid tumors resembles the physiological regression of blood vessels during development. It also disrupts wound healing.“

„IFN-γ might also affect the formation of new blood vessels after strokes or heart attacks. That’s why we want to find out more about the molecular processes behind all of this.“


Story Source:

Materials provided by Max Delbrück Center for Molecular Medicine in the Helmholtz Association. Note: Content may be edited for style and length.


Journal Reference:

  1. Thomas Kammertoens, Christian Friese, Ainhoa Arina, Christian Idel, Dana Briesemeister, Michael Rothe, Andranik Ivanov, Anna Szymborska, Giannino Patone, Severine Kunz, Daniel Sommermeyer, Boris Engels, Matthias Leisegang, Ana Textor, Hans Joerg Fehling, Marcus Fruttiger, Michael Lohoff, Andreas Herrmann, Hua Yu, Ralph Weichselbaum, Wolfgang Uckert, Norbert Hübner, Holger Gerhardt, Dieter Beule, Hans Schreiber, Thomas Blankenstein. Tumour ischaemia by interferon-γ resembles physiological blood vessel regression. Nature, 2017; DOI: 10.1038/nature22311

Max Delbrück Center for Molecular Medicine in the Helmholtz Association. „Fighting cancer with immunotherapy: Signaling molecule causes regression of blood vessels.“ ScienceDaily. ScienceDaily, 26 April 2017. <www.sciencedaily.com/releases/2017/04/170426131018.htm>

Quelle: Fighting cancer with immunotherapy: Signaling molecule causes regression of blood vessels


3 Kommentare

Lymphedema After Mastectomy Breathing Exercises & Restorative Yoga

It is not unusual for a woman to develop lymphedema after a mastectomy. Lymphedema is a sometimes-painful swelling in the soft tissues.  This can be due to the removal of lymph nodes, scar tissue, strictures, and other factors.

Manual lymph drainage massage is the usual recommended technique to treat this swelling.  It may be surprising to know that another therapy that benefits lymphedema is yoga, especially restorative yoga. When the lymphatic system is at its optimum, it is like a free flowing river, running without obstacles.  However, when the lymph nodes are removed or damaged, that same river meets obstacles and begins to slow down and this creates a pooling of fluids.  This build up in the tissues can cause swelling and inflammation and reduce oxygen in the lymphatic tissues. The white blood cells, or immune soldiers of the body, can be impaired in their function in this situation.  This may increase the risk of infection and create a possible permanent disability.  Edema is often found in the arms and legs, but can be found in other parts of the body.

Knowing how important it is to keep this fluid running like a free flowing river, we need to foster relaxation and gentle movements that encourage its increased flow.  This is especially important after breast surgery or removal of nodes, when it is paramount to undertake new activities to increase impaired lymphatic function.

The need to develop a deeper state of relaxation to counter the mental and physical stress of illness and its treatment is critically important to our health and well-being.

Practicing yoga, especially Restorative Yoga which targets the pectoral area, keeps the fluid moving through the body rather than slowing down and creating a back up.  This benefits the breasts by promoting drainage and healing and creating a sense of safety when expanding the chest.

Practicing Restorative Yoga daily will undo the harmful effects of too much sitting or inactivity.  Starting yoga practice with a knowledgeable Restorative Yoga teacher is as important as wearing a bandage or support garment.

An important thing to understand in your practice of Restorative Yoga is that you must to slow down enough to listen to what your body is telling you.  Any time you overwork your muscles or strain your healing tissues,  you run the risk of fluid build up.

Let this be the yoga practice of self-understanding.

More Great Articles

  1. How Breathing Exercises Can Raise Energy Levels For Breast Cancer Patients
  2. Breathing, Yoga and Cancer
  3. Breast Cancer Breathing Guidelines & Techniques During Exercise
  4. Diaphragmatic Breathing for Cancer Survivors
  5. Learn Natural Breath Breathing Exercise For Breast Cancer Treatment
  6. Yoga Pose for Breast Cancer – Root Lock KRIYA Breathing
  7. 4 Benefits of Breathing Exercises For Breast Cancer Treatment
  8. Why Start A Breathing Practice For Breast Cancer Recovery? Good Health!

Dawn Breast CancerAbout Dawn Bradford Lange:  Co-founder of Breast Cancer Yoga. Dawn is making a difference with Breast Cancer Yoga therapeutic products designed to support you emotionally and physically during breast cancer . We want to give you the attention and personal service you need so please email us at info@breastcanceryoga.com if you have questions.

Lymphedema After Mastectomy Breathing Exercises & Restorative Yoga


Hinterlasse einen Kommentar

Herantis Pharma’s clinical study with Lymfactin advances to high dose level

Herantis Pharma’s clinical study with Lymfactin advances to high dose level

Herantis Pharma Plc
Company release 6 March 2017 at 10:00 am

Herantis Pharma Plc’s („Herantis“) clinical study with the company’s innovative gene therapy investigational product Lymfactin® for the treatment of secondary lymphedema has advanced to highest planned dose level owing to good reported safety. A Data Monitoring Committee of independent experts recommended proceeding to high dose treatments after assessing safety data on the previously treated patients. Following the recommendation, the first high dose treatment has already been administered.

 „We are naturally very happy for the safety of Lymfactin® in the first treatments“, comments Pekka Simula, Herantis‘ CEO. „This is the first clinical study in the world to apply gene therapy for repairing damages of the lymphatic system. Safety of the patients is our #1 priority so we want to move ahead carefully. We are thrilled to announce this milestone by coincidence on March 6: World Lymphedema Day!“

„Collaboration with the participating university hospitals in this study has been excellent“, adds Katarina Jääskeläinen, Herantis‘ Project Manager for the clinical study. „Secondary lymphedema is a disfiguring, disabling disease that severely impacts the quality of life of patients. We hope our Lymfactin® will significantly improve the quality of life of patients in the future.“

The Phase 1 clinical study continues recruiting patients with breast cancer associated lymphedema at three university hospitals in Finland: In Helsinki, Tampere, and Turku. The study intends to recruit at most 18 patients by the end of 2017.

World Lymphedema Day

March 6 was officially recognized World Lymphedema Day since 2015 by e.g. the U.S. Senate. It is celebrated around the world largely thanks to the patient advocacy group Lymphatic Education & Research Network (LE&RN) to increase lymphedema awareness.

About breast-cancer associated lymphedema

Approximately 20% of breast cancer patients who undergo axillary lymph node dissection develop secondary lymphedema, a chronic, progressive, disabling and disfiguring disease that severely affects quality of life. Symptoms include a chronic swelling of an upper limb, thickening and hardening of skin, loss of mobility and flexibility, pain, and susceptibility to secondary infections. Secondary lymphedema is currently treated with compression garments, special massage, and exercises. While these therapies may relief the symptoms in some patients they do not cure lymphedema, which is caused by damage to the lymphatic system. There are currently no approved medicines for the treatment of this condition.

About Lymfactin®

Lymfactin® is a gene therapy expressing the growth factor VEGF-C specific to the development of lymphatic vessels. Based on preclinical studies Lymfactin® triggers the growth of new functional lymphatic vasculature in the damaged area and thus repairs the underlying cause of secondary lymphedema. Lymfactin®, patented by Herantis, is based on the internationally renowned scientific research of academy professor Kari Alitalo and his research group, a national centre of excellence at the University of Helsinki. Herantis also holds patents for a combination therapy, which may expand the use of Lymfactin® in other lymphedemas. See our introductory video on Lymfactin®: http://herantis.com/media/videos/

About Herantis Pharma Plc

Herantis Pharma Plc is an innovative drug development company focused on regenerative medicine and unmet clinical needs. Our first-in-class assets are based on globally leading scientific research in their fields: CDNF for disease modification in neurodegenerative diseases, primarily Parkinson’s and ALS; and Lymfactin® for breast cancer associated lymphedema, with potential also in primary lymphedema. The shares of Herantis are listed on the First North Finland marketplace run by Nasdaq Helsinki Ltd.

Distribution:

Nasdaq Helsinki
Main media
http://www.herantis.com

https://globenewswire.com/news-release/2017/03/06/931689/0/en/Herantis-Pharma-s-clinical-study-with-Lymfactin-advances-to-high-dose-level.html?utm_content=buffer4533b&utm_medium=social&utm_source

 

LE&RN Symposium Real-time Visualization of Lymph Movement

Hinterlasse einen Kommentar

https://livestream.com/LymphaticRF/Aldrich

Thanks for all the fantastic work you are doing Lymphatic Education & Research Network !


Hinterlasse einen Kommentar

Primäre Lymphödeme-Hereditary Lymphedema – NORD (National Organization for Rare Disorders)

Quelle: Hereditary Lymphedema – NORD (National Organization for Rare Disorders)

Hereditary Lymphedema

NORD gratefully acknowledges Joseph L. Feldman, MD, Senior Clinician Educator, Pritzker School of Medicine University of Chicago; Director, Lymphedema Treatment Center, NorthShore University Health System, for assistance in the preparation of this report.

Synonyms of Hereditary Lymphedema

  • primary lymphedema

Subdivisions of Hereditary Lymphedema

  • congenital hereditary lymphedema
  • hereditary lymphedema, type I
  • lymphedema-distichiasis
  • lymphedema praecox
  • lymphedema tarda
  • Milroy disease
  • Nonne-Milroy disease

General Discussion

Hereditary lymphedema is a genetic developmental disorder affecting the lymphatic system. It is characterized by swelling (edema) of certain parts of the body. The lymphatic system is a circulatory network of vessels, ducts, and nodes that filter and distribute certain protein-rich fluid (lymph) and blood cells throughout the body. In hereditary lymphedema, lymphatic fluid collects in the subcutaneous tissues under the epidermis due to obstruction, malformation, or underdevelopment (hypoplasia) of various lymphatic vessels. There are three forms of hereditary lymphedema: congenital hereditary lymphedema or Milroy disease; lymphedema praecox or Meige disease; and lymphedema tarda. Symptoms include swelling (lymphedema) and thickening and hardening of the skin in affected areas. In most cases, hereditary lymphedema is inherited as an autosomal dominant trait. Lymphedema may be classified as primary or secondary. Hereditary lymphedema is also known as primary lymphedema. Secondary lymphedema occurs because of damage to the lymphatic system from surgery, radiation therapy, trauma or infection (e.g. filariasis). Lipedema is a symmetrical accumulation of subcutaneous fat, most often in the legs. Lipedema occurs almost exclusively in females. Tenderness and bruising are also common. Typically, the feet are not swollen and thickening of the skin of the toes (Stemmer’s sign).  Lipedema is frequently misdiagnosed as lymphedema.

Signs & Symptoms

The main symptom associated with hereditary lymphedema is swelling (edema) or puffiness in different parts of the body because of the accumulation of protein-rich fluid (lymph) in the soft layers of tissue under the epidermis (lymphedema). Swelling frequently occurs in one or both legs, but may also be present in the trunk, face, genitalia and arms. When lymphedema develops in the legs, swelling is usually most noticeable in the foot and ankle but may also be present in the calf and thigh.. In some cases, swelling may cause tightness, discomfort and unusual tingling sensations (paresthesias) in the affected areas. The affected area heals poorly even after minor trauma (e.g., cut or insect bite). The skin of the affected area may become abnormally dry, thickened or scaly skin (hyperkeratosis) resulting in a “woody” texture.

Hereditary lymphedema type IA (Milroy’s disease) is characterized by swelling (edema) that is present at or shortly after birth (congenital). In rare cases, edema may develop later in life. The legs are most often affected. The extent and location of edema varies greatly from case to case even among individuals in the same family. In some cases the genitals may also be affected. Additional complications sometimes associated with hereditary lymphedema type I include upslanting toenails, small warty growths on the affected areas (papillomatosis), abnormally large or prominent leg veins, and, in males, urethral abnormalities and the development of a fluid-filled sac along the spermatic cord of the scrotum (hydrocele).

Hereditary lymphedema type II (Meige disease, lymphedema praecox) develops around puberty or shortly thereafter in most individuals. This is the most common type of primary lymphedema. In addition to lymphedema of the legs, other areas of the body such as the arms, face and larynx may be affected. Some individuals may develop yellow nails.

Lymphedema tarda is defined as primary lymphedema occurring after the age of 35. The legs are most often affected, but the arms and other areas may be affected as well.

Hereditary lymphedema may progress and, in some cases, may improve over time. Obesity makes management of lymphedema more difficult. Affected individuals with lymphedema are at risk for developing infections including bacterial infection of the skin and underlying tissue (cellulitis) or infection of the lymphatic vessels (lymphangitis). These infections are characterized by areas of warm, painful and reddened skin. Red skin “streaks” may also develop in the infected area. Increased edema is common. A general feeling of ill health (malaise), fever, chills, and/or headaches may also occur. If left untreated, cellulitis can lead to septicemia, skin abscesses, areas of ulceration, and/or tissue damage (necrosis). Cellulitis is more common in males than females. Athlete’s foot (Tinea pedis) can cause cracks in the interdigital skin, bacterial invasion and cellulitis.

In rare cases of persistent lymphedema, additional complications may develop including fluid (e.g., chyle) accumulation body cavities such as the thorax (chylothorax) and abdomen (chylous ascities). Chyle is a fat-laden cloudy fluid that is absorbed during digestion by the lymphatic vessels located around the intestine. Chyle normally flows through lymphatic vessels into the upper chest (thoracic duct) and is then deposited into veins, where it mixes with blood. In some people with hereditary lymphedema, the lymphatic vessels may rupture or become blocked (obstructed), causing chyle to accumulate in the chest cavity (chylothorax). A patient with primary chylous ascites needs to be on a no-fat diet supplemented with medium chair triglycerides and vitamins. Addition of a diuretic such as Spironolactone has been reported to be a valuable adjunct to dietary control.

Affected individuals may also be at a greater risk than the general population for developing a malignancy at the affected site. These malignancies include angiosarcoma. Angiosarcomas are cancerous tumors that develop from blood or lymphatic vessels. They may occur in any area of the body. A specific type of angiosarcoma is known as lymphagiosarcoma, or Stewart-Treves syndrome. This cancerous tumor may rarely develop in longstanding cases of primary or secondary lymphedema. Angiosarcoma occurs in the lymphedematous extremity but can spread to the adjacent trunk and lungs.

Causes

Many researchers believe that hereditary lymphedema may result from changes (mutations) in one of the different disease genes (genetic heterogeneity). Most cases of hereditary lymphedema type IA and type II are inherited as autosomal dominant traits. Genetic diseases are determined by the combination of genes for a particular trait that are on the chromosomes received from the father and the mother. Dominant genetic disorders occur when only a single copy of an abnormal gene is necessary for the appearance of the disease. The abnormal gene can be inherited from either parent, or can be the result of a new mutation (gene change) in the affected individual. The risk of passing the abnormal gene from affected parent to offspring is 50 percent for each pregnancy regardless of the sex of the resulting child.

Investigators have determined that some cases of hereditary lymphedema type IA (Milroy’s disease) occur because of mutation in the FLT4 gene which encodes of the vascular endothelial growth factor receptor 3 (VEGFR-3) gene located on the long arm (q) on chromosome 5 (5q35.3). Chromosomes, which are present in the nucleus of human cells, carry the genetic information for each individual. Human body cells normally have 46 chromosomes. Pairs of human chromosomes are numbered from 1 through 22 and the sex chromosomes are designated X and Y. Males have one X and one Y chromosome and females have two X chromosomes. Each chromosome has a short arm designated “p” and a long arm designated “q”. Chromosomes are further sub-divided into many bands that are numbered. For example, “chromosome 5q35.3” refers to band 35.3 on the long arm of chromosome 5. The numbered bands specify the location of the thousands of genes that are present on each chromosome.

Investigators have determined that some cases of hereditary lymphedema type II (Meige disease) occur because of mutations of the ‘forkhead’ family transcription factor (FOXC2) gene located on the long arm (q) of chromosome 16 (16q24.3).

Affected Populations

Hereditary lymphedema affects females more often than males. The estimated prevalence of these disorders is 1 in 6,000 individuals within the general population. Hereditary lymphedema type II (Meige syndrome) is the most common form accounting for approximately 80 percent of cases. The prevalence of hereditary lymphedema type I (Milroy disease) is unknown. Approximately 200 cases have been reported in the medical literature.

Diagnosis

The diagnosis of hereditary lymphedema may be confirmed by a thorough clinical evaluation and a variety of specialized imaging tests including lymphoscintigraphy, ultrasound, and magnetic resonance imaging (MRI). During lymphoscintigraphy, a radioactively labeled colloid substance is injected intradermally into either the hands or feet. The time required for the tracer to be transported from the point of injection to the regional lymph nodes is recorded. In congenital lymphedema, the tracer may move sluggishly or not move from the site of injection. During an ultrasound, reflected sound waves create an image of the developing fetus. An ultrasound is used to rule out other conditions. A Doppler ultrasound can evaluate venous conditions such as varicose veins and venous blood clots. An MRI uses a magnetic field and radio waves to produce cross-sectional images of particular organs and bodily tissues. An MRI is used to detect findings characteristic of hereditary lymphedema including swelling (edema), a mass surrounded by a sac containing lymph fluid (lymphocele), and the formation of fibrous tissue (fibrosis).

Standard Therapies

Treatment

No gene therapy for hereditary lymphedema is currently available. There is no FDA approved medication to treat lymphedema. Lymphedema risk reduction practices should be followed to reduce complications such as infection and an increase in swelling. Treatment is aimed at reducing swelling and preventing infection. Complete decongestive therapy (CDT) is a form of treatment in which specialized manual techniques (manual lymph drainage) is combined with multilayered compression bandaging, meticulous skin care, exercise, and the use of well-fitted compression garments.. Decongestive and conditioning exercises are important components of CDT. Patients and their parents/caregivers should be counseled on the importance of adhering to lymphedema management recommendations to prevent progression the lymphedema. Antibiotics can be used to treat infections such as cellulitis or as a preventive (prophylactic) measure in individuals with recurrent infections. Athlete’s foot can be treated with antifungal topical medications.

Various surgical techniques have been used to treat individuals with hereditary lymphedema including the surgical joining of small lymphatic vessels to nearby small veins (microsurgical anastomosis) has had some limited success in people with lymphedema. The goal of this surgery is to reduce swelling by creating new pathways for lymphatic fluid flow and “rechanneling” this flow into the venous system. According to the medical literature, these therapies have had only limited effectiveness. Reducing operations are available to remove excess fibrotic tissue in cases of severe lymphedema. Continued use of compression garments is necessary after reducing surgery. Liposuction has not been found to be effective in primary lymphedema.

Individuals with hereditary lymphedema should avoid long periods of immobility with legs in a dependent position. Affected individuals should also take special care to avoid wounds in any affected area because of a reduced resistance to infection. Certain medications such as calcium channel blocking drugs and non-steroidal anti-inflammatory drugs may worsen swelling in the legs and the benefits and risks need to be discussed with the patient’s physician. Excessive salt intake can cause fluid retention.

Genetic counseling will benefit people with hereditary lymphedema and their families. Rehabilitation therapy may be necessary in cases where extreme lymphedema impairs daily activities.

 

Investigational Therapies

Information on current clinical trials is posted on the Internet at www.clinicaltrials.gov. All studies receiving U.S. government funding, and some supported by private industry, are posted on this government web site.

For information about clinical trials being conducted at the NIH Clinical Center in Bethesda, MD, contact the NIH Patient Recruitment Office:

Tollfree: (800) 411-1222
TTY: (866) 411-1010
Email: prpl@cc.nih.gov

For information about clinical trials sponsored by private sources, contact:
www.centerwatch.com.

For information about clinical trials conducted in Europe, contact:
https://www.clinicaltrialsregister.eu/

Botanicals such as the Benzopyrones and Saponins (e.g., horse chestnut seed extract) as well as the trace element Selenium have been advocated by some as adjunctive treatments for lymphedema.

Benzopyrones, a group of substances such as coumarin, hydroxethylrutin and flavinoid derivatives, have been used for the treatment of individuals with hereditary lymphedema. These drugs breakdown proteins found in lymph and may stimulation lymph flow thereby reducing lymph accumulation and subsequent swelling. However, the effectiveness of such medications is unproven and under debate. Hepatotoxicity has been reports in up to 6% of the patients taking coumarin. More research is necessary to determine the long-term effectiveness and safety of benzopyrone therapy in individuals with hereditary lymphedema.

Occasionally, drugs that promote fluid mobilization (i.e., diuretics) have been used for people with lymphedema. These medications increase urinary output and may help to reduce swelling in some affected individuals. However, diuretics have not been proven successful in reducing the swelling in primary lymphedema but may be beneficial in patients with mixed origin edema, e.g., phlebolymphedema. The prolonged use of diuretics for the treatment of hereditary lymphedema should be carefully directed by a physician as these medications may have several long-term side effects.

Contact for additional information about hereditary lymphedema:

Joseph L. Feldman, MD
Senior Clinician Educator
Pritzker School of Medicine
University of Chicago
Director, Lymphedema Treatment Center
NorthShore University HealthSystem

 


Hinterlasse einen Kommentar

Understanding Lymphedema – Lymphedema & Wound Care Session – LE&RN -David Zawieja PhD

Einen super interessanten Beitrag! Herzlichen Dank für die Bereitstellung.