Our patient speakers at the Amyloidosis Speakers Bureau are powerful educators and offer compelling insights. In this clip, Dan shares how his provider commented on his heart’s thickened walls – you’ve got athlete’s heart, and all’s good. A shocking missed opportunity to suspect cardiac amyloidosis.
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AL Amyloidosis: Diagnosis Begins With Suspicion
The diagnosis of amyloidosis can be challenging for several reasons.
- First and foremost, presenting symptoms are often nonspecific and common to other conditions that can send clinicians in multiple directions.
- Second, due to the variability of presenting symptoms, rarely are two patient presentations identical.
- Third, the diagnostic process requires (a) the confirmation of amyloidosis, and (b) the typing of amyloidosis, only after which can an appropriate treatment regimen be developed.
The perceived rarity of the disease itself gives providers pause to consider. Collectively, as a result of these reasons, diagnosis is often delayed and/or misdiagnosed, leading to devastating consequences for patients. Often, the key to diagnosis begins with developing a clinical suspicion.
DEVELOPING A CLINICAL SUSPICION FROM SYMPTOMS
The first step in diagnosing AL amyloidosis is to develop a clinical suspicion, done through connecting the seemingly random presenting symptoms.
As seen in the figure above, multiple pathologies are often present with AL amyloidosis1. The most common is cardiac involvement, which also brings the highest mortality. Other common presentations range from nephropathy, including proteinuria (> 60% of patients), hepatomegaly (>50% of patients), neuropathy, whether autonomic (20% of patients) or peripheral (10-20% of patients), macroglossia (17% of patients), periorbital purpura (15% of patients) and GI manifestations (approximately 7% of patients).
Symptoms do not develop at the same time, nor in the same sequence from patient to patient. As a result, patients and providers often play “whack-a-mole,” going from specialist to specialist for specific symptoms. Misdiagnoses along the way are common, leading patients down paths that prove unproductive and, in some cases, counterproductive. This takes time, which is exactly what patients do not realize they do not have.
Suspicion of amyloidosis should be very high when a patient presents with heart failure combined with a constellation of unexplained extracardiac symptoms such as neuropathy, bleeding, carpal tunnel syndrome, nephrotic syndrome, proteinuria, diarrhea, hepatomegaly, peripheral and autonomic neuropathy, macroglossia, and periorbital purpura.1
ALGORITHM FOR DIAGNOSING AL AMYLOIDOSIS1
The figure below illustrates the current systematic, stepwise process for diagnosing amyloid light chain (AL) amyloidosis and differentiating it from other cardiomyopathies. It identifies each type of test that is essential for suspicion of AL amyloidosis, diagnosing the disease and typing of the amyloidogenic free light chains (FLCs).
ACR = albumin/creatinine ratio
DPD = 99mTc-3-diphosphono-1,2-propanodicarboxylic acid
Echo = echocardiography
EKG = electrocardiography
LFT = liver function test
MRI = magnetic resonance imaging
NT-proBNP = N-terminal pro–brain natriuretic peptide
PYP = 99mTc-pyrophosphate
SIFE = serum immunofixation electrophoresis
UIFE = urine immunofixation electrophoresis
TYPING AND CONFIRMING DIAGNOSIS1
Once the presence of amyloid has been confirmed, it is imperative to next identify the type of amyloid fibril in order to avoid misdiagnosis and initiation of incorrect or inappropriate treatment, which could have disastrous consequences for a patient.
The most common methods of amyloid fibril typing include immunohistochemistry or laser capture, followed by mass spectrometry. As the accuracy of immunohistochemistry is dependent on the expertise of the laboratory and needs an extensive panel of antibodies for accurate reporting, laser capture with mass spectrometry has become the method of choice for amyloid fibril typing.
Despite advances in noninvasive imaging, tissue biopsy remains a common and important confirmational step in most cases.
Once a diagnosis of amyloidosis has been confirmed, along with the specific type, an appropriate treatment regime can then be determined.
CONCLUSION – WHY EARLY DIAGNOSIS MATTERS
With AL amyloidosis, time is of the essence for patients. This is an aggressive disease where early treatment intervention can truly extend lives and improve QoL. As recently as the 1990s, this was considered a terminal disease with a high mortality rate, often offering patients months to a few years to live. With earlier diagnosis and advancements in treatments, survival is extending and QoL is improving.
IN CLOSING
The key take-aways are two-fold: (1) when confronted with multiple unexplained symptoms, suspect multi-system diseases like amyloidosis, and (2) remember that early diagnosis is key for patient survival.
For more detail on diagnosing and treating AL amyloidosis, please see the paper referenced below.
Source:
(1) Wechalekar, A, Fontana, M, Quarta, C. et al. AL Amyloidosis for Cardiologists: Awareness, Diagnosis, and Future Prospects: JACC: CardioOncology State-of-the-Art Review. J Am Coll Cardiol CardioOnc. 2022 Nov, 4 (4) 427–441.
Macroglossia & Amyloidosis
WHAT IS IT?
According to the NIH (1), macroglossia is the abnormal enlargement of the tongue in proportion to other structures in the mouth. It usually occurs secondary to an underlying disorder that may be present from birth (congenital) or acquired.
SYMPTOMS
Symptoms associated with macroglossia may include drooling, speech impairment, difficulty eating, noisy and/or high-pitched breathing (stridor), snoring, airway obstruction, abnormal growth of the jaw and teeth, and ulceration. In some cases, the tongue may protrude from the mouth. (1) (3)
Talking may be affected. The large size of the tongue may also cause abnormal development of the jaw and teeth, resulting in misaligned or protruding teeth. Ulceration and dying tissue on the tip of the tongue may be other symptoms of the disorder. (3)
In addition to an enlarged tongue it is common to see indentations around the tongue perimeter from the constant pressure against the teeth.
Patients who graciously offered their picture for this blog reinforce many of these symptoms, including TMJ, difficulty swallowing, and breathing. Reiterated almost unanimously, eating is a problem – chewing and swallowing, clearing food from their mouth. Food gets stuck in front of their teeth. Speech is affected, and they often sound “slushy.” Snoring can get so bad it wakes them (and partners) up during the night. In addition, sometimes, their tongue gets sore from rubbing against their teeth.
WHAT CAUSES IT?
Macroglossia can be associated with a wide range of congenital (present from birth) and acquired conditions (e.g., malignancies, metabolic/endocrine disorders, inflammatory or infectious diseases; amyloidosis), or it can occur as an isolated feature (with no other abnormalities). In most cases, it is due to vascular malformations (blood vessel abnormalities) and muscular hypertrophy (an increase in muscle mass). (1)
Macroglossia is the most frequent oral manifestation of amyloidosis and may be found as the only presenting symptom of the disease or included in a longer list of other symptoms. In addition, while occurring much more frequently in AL Light Chain amyloidosis, it can also accompany hereditary ATTR Transthyretin amyloidosis. (2, 4)
HOW IS IT TREATED?
There is no cure, but treatments can manage the symptoms. Treatment depends upon the underlying cause and severity and may range from speech therapy in mild cases, to orthodontic procedures, to surgical reduction in more severe cases. (1) (3)
Sources
- National Institutes of Health
- NIH National Library of Medicine
- National Organization for Rare Disorders
- https://ashpublications.org/blood/article/116/21/5007/66459/Macroglossia-Not-Always-AL-Amyloidosis
Ref 5 (picture only)
https://www.mayoclinic.org/diseases-conditions/amyloidosis/multimedia/enlarged-tongue/img-20008056
Amyloidosis and the Gut
Dr. Melissa Hershman, assistant professor from the OHSU Division of Gastroenterology & Hepatology, provides an informative overview of how, and where, amyloidosis can present in the G.I. tract. She reviews patient symptoms, many of which are nonspecific and can be associated with other more common issues, delaying diagnosis. Dr. Hershman goes through how G.I. amyloidosis is tested for, where in the G.I. tract biopsies are most commonly performed, and how the tissue is stained for diagnosis by pathology. In closing, she reviews the array of treatments available to assist patients.
Hereditary Amyloidosis: The V122I Variant
Hereditary Amyloidosis in Americans of African Descent: ATTR V122I Variant
Amyloidosis, still considered a relatively rare disease, can take several forms. Each slightly different, but most sharing similar debilitating symptoms of cardiac and/or neurological impairment, or both. It is viewed by many experts that amyloidosis has been presenting in plain sight and missed, or wildly underdiagnosed, for decades and, in some cases, generations. Thankfully, education to raise awareness within the healthcare community, along with improvements in diagnostic tools and testing, the journey to diagnosis and treatment is becoming more visible.
The hereditary transthyretin amyloidosis (hATTR; also called variant amyloidosis ATTRv) type results from a genetic mutation of a protein, transthyretin, which is produced in the liver and circulates throughout the body. The mutation causes the TTR protein to misfold, becoming unstable and depositing in organs and nerve systems causing impairment and eventual organ failure. Common symptoms for the disease include bilateral carpel tunnel syndrome, muscle weakness, cardiomyopathy, polyneuropathy, GI issues especially chronic diarrhea and constipation, and both nuisance and serious concerns and if untreated can lead to death. Early diagnosis, genetic testing to identify the exact genetic mutation, and treatment are important to slow the progression of the disease and conserve quality of life.
SIGNIFICANTLY UNDER-DIAGNOSED
Considered a rare disease, advances in diagnosis have shown that it is less rare than originally thought.
Familial amyloidosis caused by a transthyretin mutation occurs in approximately 1 in 100,000 Caucasians in the U.S, and more commonly in African Americans (approximately 4% in that population). This condition is prevalent in Portugal, Sweden, Japan, Ireland, Spain, France, Finland, Germany and Greece. Symptoms usually begin between 40 and 65 years of age.
https://rarediseases.org/rare-diseases/amyloidosis/
To date over one hundred variants of TTR have been identified as causing ATTR amyloidosis and they are distributed worldwide with concentrations in various ethnic populations. One variant, V122I is most commonly found in people with African and especially West African ancestry. It has been distributed worldwide but especially in North America and the Caribbean through historic slave trade and the migration of populations. This variant is most often associated with ATTR-CM (Amyloidosis with cardiomyopathy) and heart failure.
Worldwide Carrier Rates of TTR V122I in Self-Reported Countries/Regions
From Multicenter Study JAMA 2019 Dec 10;322(22):2191-2202.
doi: 10.1001/jama.2019.17935.
In an article by J. Buxdaum and F. Ruberg in the Journal Genetics in Medicine January 2017, the authors stated the following findings.
Since the identification of a valine-to-isoleucine substitution at position 122 (TTR V122I; pV142I) in the transthyretin (TTR)-derived fibrils extracted from the heart of a patient with late-onset cardiac amyloidosis, it has become clear that the amyloidogenic mutation and the disease occur almost exclusively in individuals of identifiable African descent. In the United States, the amyloidogenic allele frequency is 0.0173 and is carried by 3.5% of community-dwelling African Americans. Genotyping across Africa indicates that the origin of the allele is in the West African countries that were the major source of the slave trade to North America. At autopsy, the allele was found to be associated with cardiac TTR amyloid deposition in all the carriers after age 65 years; however, the clinical penetrance varies, resulting in substantial heart disease in some carriers and few symptoms in others. The allele has been found in 10% of African Americans older than age 65 with severe congestive heart failure. At this time there are potential forms of therapy in clinical trials. The combination of a highly accurate genetic test and the potential for specific therapy demands a greater awareness of this autosomal dominant, age-dependent cardiac disease in the cardiology community.
Genet Med advance online publication 19 January 2017
The prevalence and distribution of the amyloidogenic transthyretin (TTR) V122I allele in Africa.
1:CAS:528:DC%2BC28XhsFSlsbfJ 10.1002/mgg3.231 Mol Genet Genomic Med. 2016; 4: 548-556
Dr. Martha Grogan, director of the Cardiac Amyloid Clinic of Mayo Clinic in Rochester, Minnesota commented in an interview published in the Mayo News Network (https://newsnetwork.mayoclinic.org/discussion/expert-alert-cardiac-amyloidosis-masquerades-as-other-conditions-1-type-affects-more-black-americans/) that amyloidosis can be tricky to suspect because symptoms may not be initially present and they may mimic other more common diseases. Currently there are options for free saliva or blood tests through several pharmaceutical companies. To determine the type of the disease genetic testing is important.
The University of Pennsylvania and the Icahn School of Medicine at Mount Sinai conducted a study of 52,492 participants of which 11,143 were of self-reported African ancestry. https://jamanetwork.com/journals/jama/fullarticle/2757227
An excellent discussion of the results emphasizes the conclusion that a significant association of TTR V122I and heart failure in the tested population, primarily in those of West African ancestry, exists. In addition, they confirm previous studies that have suggested a high rate of underdiagnosis of hATTR-CM in cases of cardiomyopathy and heart failure in elderly patients of African Ancestry. The discussion further suggests that this is likely due to lack of information and familiarity with the disease in the medical community.
CITATION: Damrauer SM, Chaudhary K, Cho JH, et al. Association of the V122I Hereditary Transthyretin Amyloidosis Genetic Variant With Heart Failure Among Individuals of African or Hispanic/Latino Ancestry. JAMA. 2019;322(22):2191–2202. doi:10.1001/jama.2019.17935. https://pubmed.ncbi.nlm.nih.gov/31821430/
Discussion of a different study of 7,514 African American participants in the US considered the question of the association between genetic variation and the risk of heart failure. This study was conducted by the University of Alabama, University of Colorado, Columbia University, and Cornel University. The results are similar to those in the University of Pennsylvania study discussed above, with additional comments that more subtle symptoms and changes may be apparent well before the typical onset of significant disease, average age 65, and the need for earlier screening for early detection and treatment.
An autosomal-dominant disease, hATTR-CM has a median survival of nearly 2.5 years without treatment after receiving a diagnosis.34,35 Extrapolating the hATTR-CM–associated Val122Ile variant frequency to the population level suggests that approximately 1.4 million Black individuals carry this variant implicated in the development of heart failure and reduced overall survival. Despite the possible clinical implications, the Val122Ile TTR variant, which is seen relatively more commonly among individuals of African ancestry, is not included in the list of clinically actionable deleterious variants compiled by the American College of Medical Genetics and Genomics.9 Thus, this potentially deleterious variant may not be reported as clinically actionable, thereby reducing physician vigilance for hATTR-CM.
Findings In this retrospective cohort study that included 7,514 Black participants in the US with a median 11.1 years of follow-up, the incidence of heart failure was 15.6 per 1000 person-years among Val122Ile variant carriers compared with 7.2 per 1000 person-years among noncarriers, with an adjusted hazard ratio of 2.43.
Meaning Being a carrier of the Val122Ile variant was significantly associated with an increased risk of heart failure among Black individuals living in the US.
CITATION: Parcha V, Malla G, Irvin MR, et al. Association of Transthyretin Val122Ile Variant With Incident Heart Failure Among Black Individuals. JAMA. 2022;327(14):1368–1378. doi:10.1001/jama.2022.2896
From Dr. Kevin Alexander, Stanford Amyloid Center
SUMMARY
Despite the evidence that a meaningful 3-4% of the US Black population of West African ancestry likely carries the V122I genetic mutation, hereditary TTR amyloidosis remains significantly underdiagnosed and undertreated in this population.
Cardiac symptoms in elderly black patients have too often been treated for more common cardiomyopathy and heart conditions, resulting in lack of appropriate treatment and often death. Because of lack of awareness in the medical community and reduced access to expert medical care, more subtle symptoms in younger black patients generally have not caused the physicians to consider amyloidosis. Additionally, lack of genetic testing can mean that entire families are unaware of the implications of the disease.
Amyloidosis can be devastating to both patients and their families. Increased awareness of the disease, availability of testing, and FDA-approved therapies are slowly beginning to shift this dynamic. However, there is still much work to be done to close the gap between diagnosed cases and the population estimated to be affected.
Early diagnosis is key.
For additional information regarding hereditary amyloidosis:
Central Nervous System and Ocular Involvement in hATTR
Dr. Chafic Karam, professor of neurology from the University of Pennsylvania, provides an informative overview of how certain mutations of hereditary transthyretin amyloidosis are being diagnosed in the central nervous system (CNS), such as the eye. It has been long believed that amyloidosis did not cross the blood brain barrier; however, evidence is showing otherwise. In addition, while most of the transthyretin protein originates in the liver, local production is found in other areas of the body such as the brain and retina. Dr. Karam will discuss how patients might present, the developing state of diagnostics, and treatments available. A slower developing symptom, with patients now living longer he predicts neurologists will see more and more patients with CNS and ocular involvement.
Timing and co-occurrence of red-flag symptoms prior to a diagnosis of light chain (AL) amyloidosis
Dr. Anita D’Souza, associate professor of hematology and medical oncology from the Medical College of Wisconsin, discusses recent study findings regarding the timing and co-occurrence of symptoms within the three years prior to a diagnosis of light chain (AL) amyloidosis. Organized by organ system, Dr. D’Souza lists red-flag symptoms that patients may experience, typically presenting in varying combinations. Analyzing EHR records she sought to understand whether red-flag symptoms were indeed being identified, and how their occurrence would accumulate over time towards diagnosis.
Bottom line:
- This work confirms that patients are being diagnosed within the healthcare system with multiple red-flag diagnoses before AL amyloidosis is formally diagnosed.
- It is possible to catalog these diagnoses from electronic health records data and thus has the potential for earlier diagnosis of this complex disease.
- This study shows the timing and combinations between these diagnoses and lays the foundation to develop clinical algorithms aimed at earlier recognition of AL amyloidosis.
ATTR-CM (cardiomyopathy) vs ATTR-PN (peripheral neuropathy)
Over the course of the past few months, we spent time discussing two of the most common hallmark symptoms of ATTR amyloidosis: cardiomyopathy and peripheral neuropathy. In this article, we’ll briefly recap both hallmark symptoms as well as bring it all together by discussing the two most common forms of ATTR amyloidosis: ATTR cardiomyopathy (ATTR-CM) and ATTR peripheral neuropathy (ATTR-PN).
To recap …
Cardiomyopathy
Cardiomyopathy is a broad term that is used to describe disease of the heart muscle, making it difficult for the heart to provide the body with an adequate blood supply. It is a common cause of sudden cardiac arrest and sudden cardiac death, which can lead to heart failure and even death.
Types of Cardiomyopathy:
- Dilated Cardiomyopathy → dilation of the left ventricle prevents the heart from pumping effectively
- Hypertrophic Cardiomyopathy → abnormal thickening of the heart muscle most commonly surrounding the left ventricle
- Restrictive Cardiomyopathy → stiffening of the heart muscle results in an inelasticity
- Arrhythmogenic Right Ventricular Dysplasia → scar tissue replaces healthy tissue of the right ventricle
- Unclassified Cardiomyopathy → all other forms of cardiomyopathy fall within this category
Peripheral Neuropathy
Peripheral neuropathy, also referred to as polyneuropathy, is a very broad term used to describe damage of the peripheral nerves. Damage to these nerves most commonly causes numbness, pain, and weakness but can affect other areas of the body including, but not limited to, circulation, digestion, and urination.
Types of Neuropathy:
- Motor Neuropathy → damage to the motor nerves
- Sensory Neuropathy → damage to sensory nerves
- Autonomic Nerve Neuropathy → damage to autonomic nerves that control involuntary functions
- Combination Neuropathies → damage to a mix of 2 or 3 of these other types of neuropathies
ATTR Amyloidosis
The origin of this disease can be genetic (hATTR) or non-genetic, or “wild-type” (ATTRwt). Regardless, in ATTR amyloidosis, the transthyretin (TTR) protein is misfolded and aggregates, forming amyloid fibers that deposit into tissues and organs. The deposition of protein causes organ dysfunction and can even cause organ failure and death.
ATTR-CM and ATTR-PN
Depending on the location of protein deposition, the disease is referred to in different ways. For instance, when the primary location of amyloid deposit is in the heart, the disease is referred to as ATTR cardiomyopathy (ATTR-CM). On the other hand, when the primary location of amyloid deposit is in the nerves, the disease is referred to as ATTR peripheral neuropathy (ATTR-PN).
ATTR-CM impairs the heart’s ability to pump effectively. A major challenge surrounding this disease is that symptoms of ATTR-CM are often similar to other heart conditions like enlarged heart and heart failure. This makes diagnosing the disease increasingly more difficult. Individuals with hATTR typically present symptoms in their 50s and 60s, whereas those with ATTRwt may not present symptoms until their 70s and later.
Common Symptoms of ATTR-CM:
- Fatigue
- Swelling of legs, ankle, or abdomen
- Shortness of breath with activity
- Orthostatic hypotension
- Difficulty breathing when lying down
- Arrhythmia
ATTR-PN impairs the function of the nervous system. While amyloid most commonly builds up in the peripheral nervous system, deposition can also occur in the autonomous system. This results in a diversity of symptoms that are specific to the site of amyloid deposition. Symptom presentation is much more diverse, occurring as early as the 20s, or as late in life as the 70s.
Common Symptoms of ATTR-PN:
- Carpal tunnel syndrome
- Diarrhea and/or constipation
- Nausea, vomiting
- Loss of appetite
- Sexual dysfunction
- Muscle weakness
- Eye problems
- Orthostatic hypotension
Expert Insights – Cardiac Clues and Clinical Signs
In part 1 of a 2-part series, Dr. Keyur Shah, cardiologist from VCU Health’s cardiac amyloidosis care team, discusses the two most common types of transthyretin (TTR) amyloidosis: hereditary and wild-type. He details how ATTR cardiomyopathy amyloidosis presents and manifests itself to impair the heart. Dr. Shah lists clinical clues, “red flags,” and biomarkers which can raise suspicion of the presence of amyloidosis. Next, he discusses insights that can be gained from echocardiograms, electrocardiograms, and cardiac MRIs and how they offer possible indicators of the disease presence. Once amyloidosis is suspected, definitive diagnosis testing is next.
In part 2 of a 2-part series, Sarah Paciulli, Heart Failure Nurse Practitioner, from VCU Health’s cardiac amyloidosis care team, continues from where Dr. Keyur Shah ended in Part I and discusses here in Part II the non-cardiac clues of transthyretin (TTR) amyloidosis. She expands the list of clinical clues and “red flags” that clinicians should be alert to, including orthopedic manifestations, erectile dysfunction, and polyneuropathy.
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References:
https://www.pfizer.com/news/articles/understanding_this_rare_disease_called_attr_amyloidosis
https://www.mayoclinic.org/diseases-conditions/cardiomyopathy/symptoms-causes/syc-20370709
https://www.yourheartsmessage.com
https://healthjade.net/familial-amyloidosis/
https://my.clevelandclinic.org/health/diseases/14737-neuropathy
https://www.hopkinsmedicine.org/health/conditions-and-diseases/peripheral-neuropathy
https://www.mayoclinic.org/diseases-conditions/peripheral-neuropathy/symptoms-causes/syc-20352061
https://practicalneurology.com/articles/2021-july-aug/neuromuscular-amyloidosis
https://healthjade.net/familial-amyloidosis/
The Systemic Amyloidoses vs. Parkinson’s vs. Alzheimer’s
Current medical education on amyloid diseases is 25 years old and materially outdated, punctuated by rapid advancement in the last five years. Hear from renowned Dr. Jeff Kelly from Scripps Research, developer of ATTR drug tafamidis, about the current biology and how amyloid diseases such as the Systemic Amyloidoses (ATTR and AL), Parkinson’s and Alzheimer’s are today believed to be more similar than different.
For those interested in learning more about neurodegenerative diseases driven by amyloid protein misfolding, below is an excellent video from May 17, 2024 by Dr. Kelly.
AL Amyloidosis: Symptoms, Diagnostics and Challenges
Dr. Gurbakhash Kaur, co-director of the amyloidosis program at UT Southwestern Medical Center, opens with a brief overview of the disease. Focusing on AL Amyloidosis, she shares how heterogeneously this disease presents – it can be very different from patient to patient, amplifying the diagnostic challenge. Symptoms may also be more commonly associated with other diseases. For example, proteinuria is often associated with diabetes and hypertension. However, clinicians should look at the bigger picture to be sure, as amyloidosis can also be a cause. Dr. Kaur reviews what should be in a basic workup when one has a clinical suspicion for amyloidosis. Once tested positive for amyloidosis, a second necessary step is to determine the type of amyloidosis. This is critical as it will determine the appropriate course of treatment. In closing Dr. Kaur summarizes the goals of treatment, what is available today, and what drugs are in clinical trials, giving lots of hope to the AL amyloidosis community.