Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.
Amyloidosis is a group of diseases that result from the abnormal
deposition of a
particular protein, called amyloid, in various tissues of the
body.
Amyloid protein can be deposited in a localized area and may not
be harmful or only affect a single tissue of the body. This form of amyloidosis is called localized amyloidosis. Amyloidosis that affects tissues throughout the body is referred to as systemic amyloidosis. Systemic amyloidosis can cause serious changes in virtually any organ of the
body.
Amyloidosis can occur as its own entity or "secondarily" as a result of
another
illness, including multiple myeloma, chronic infections (such as
tuberculosis or osteomyelitis), or chronic inflammatory
diseases (such as
rheumatoid arthritis and ankylosing spondylitis). Amyloidosis can also be localized to a specific body area from aging. This localized form of amyloidosis does not have systemic implications for the rest of the body. The protein
that
deposits in the brain of patients with Alzheimer's disease is a
form of
amyloid.
Systemic amyloidosis has been classified into three major types that are very different from each other. These are distinguished by a two-letter code that begins with an A (for amyloid). The second letter of the code stands for the protein that accumulates in the tissues in that particular type of amyloidosis. The types of systemic amyloidosis are currently categorized as primary (AL), secondary (AA), and hereditary
(ATTR).
In addition, other forms of amyloidosis include beta-2 microglobulin amyloidosis and localized amyloidoses.
Primary amyloidosis
Primary amyloidosis, or AL, occurs when a specialized cell in the bone marrow (plasma cell) spontaneously overproduces a particular protein portion of an antibody called the light chain. (This is why it is coded as AL.) The deposits in the tissues of
people with primary amyloidosis are AL proteins. Primary amyloidosis can occur with a bone marrow cancer of plasma cells called multiple myeloma. Primary amyloid is not associated with any other diseases but is a disease entity of its own, conventionally requiring chemotherapy treatment. Researchers at the Mayo Clinic in Rochester, Minnesota, and Boston University in Boston, Massachusetts, have demonstrated benefits from stem-cell transplantation, harvesting patients' own stem cells to treat primary amyloidosis.
Secondary amyloidosis
When amyloidosis occurs
"secondarily" as a result of another illness, such as multiple myeloma, chronic
infections (for example, tuberculosis or osteomyelitis), or chronic inflammatory
diseases (for example, rheumatoid arthritis and ankylosing spondylitis), the condition is referred to as secondary amyloidosis or AA. The amyloid tissue deposits in secondary amyloidosis are AA proteins. The treatment of patients' secondary amyloidosis is directed at treating the underlying illness in that particular patient.
Familial amyloidosis
Familial amyloidosis, or ATTR, is a rare form of inherited amyloidosis. The amyloid deposits in familial amyloidosis are composed of the protein transthyretin, or TTR, which is made in the liver. Familial amyloidosis
is an inherited autosomal dominant in genetics terminology. This means that for the offspring of a person with the condition, there is a 50% chance of inheriting it.
Beta-2 microglobulin amyloidosis
Beta-2 microglobulin amyloidosis occurs when amyloid deposits develop in patients on dialysis with longstanding kidney failure. The amyloid deposits are composed of beta-2 microglobulin protein and are often found around joints.
Localized amyloidoses
The many forms of localized amyloidosis are a result of amyloid deposits in specific areas of the body and are distinct from systemic forms of amyloidosis that deposit amyloid throughout the body. Localized amyloid deposits occur in the brain from Alzheimer's disease. In various tissues, often with aging, amyloid can be locally produced and deposited to cause tissue injury.
Congestive heart failure (CHF) is a condition in which the heart's function as a pump is inadequate to meet the body's needs. A poor blood supply resulting from congestive heart failure may cause the body's organ systems to fail, leading to a weakened heart muscle and fluid accumulation in the lungs and body tissue. There are many diseases that can impair pumping efficiency and symptoms of congestive heart failure including fatigue, diminished exercise capacity, shortness of breath, and swelling. Treatments include lifestyle modifications, medications, heart transplant, and therapy.
Multiple myeloma is a form of cancer that develops in plasma cells, the white blood cells that make antibodies. Symptoms include bone pain, weakness, extreme thirst, nausea, frequent urination, and broken bones. Treatment of multiple myeloma depends upon the staging and symptoms of the disease.
Carpal tunnel syndrome is a condition in which irritation of the wrist's median nerve causes tingling and numbness of the thumb, index, and the middle fingers. This condition is known as tarsal tunnel syndrome in the ankles and feet. Treatment of carpal tunnel syndrome depends on the severity of the symptoms and the nature of any disease that might be causing the symptoms.
Osteomyelitis is an infection of the bone. Potential causes include injections around the bone, fractures that puncture the skin, recent surgeries, and bacterial infections that travel from other areas of the body, spreading through the blood to the bone. Symptoms include pain, fever, chills, stiffness, and nausea. Treatment involves antibiotics and pain medications. Surgery is sometimes necessary.
Orthostatic hypotension symptoms include lightheadedness, weakness, blurred vision, and syncope or passing out. Causes of orthostatic hypotension include dehydration, anemia, medication, blood loss, low blood pressure, heat related illnesses and more. Treatment of orthostatic hypotension depends on the underlying cause.
Sudden cardiac arrest is an unexpected, sudden death caused by sudden cardiac arrest (loss of heart function). Causes and risk factors of sudden cardiac arrest include (not inclusive): abnormal heart rhythms (arrhythmias), previous heart attack, coronary artery disease, smoking, high cholesterol, Wolff-Parkinson-White Syndrome, ventricular tachycardia or ventricular fibrillation after a heart attack, congenital heart defects, history of fainting, and heart failure, obesity, diabetes, and drug abuse. Treatment of sudden cardiac arrest is an emergency, and action must be taken immediately.
Brain lesions (lesions on the brain) are caused by trauma, inflammation, autoimmune diseases, cancers, other diseases, stroke, bleeding, pituitary adenomas, and cerebral palsy. Symptoms of brain lesions include headache, nausea, fever, neck pain and stiffness, affected vision and speech, weakness or paralysis to one side of the body. Diagnosis of brain lesions is generally with imaging studies like CT or MRI scans. Treatment and prognosis of brain lesions depends on the cause of the lesion.
Osteomyelitis is infection in the bone. Osteomyelitis can occur in infants, children, and adults. Different types of bacteria typically affect the different age groups. In children, osteomyelitis most commonly occurs at the ends of the long bones of the arms and legs, affecting the hips, knees, shoulders, and wrists. In adults, it is more common in the bones of the spine (vertebrae) or in the pelvis.
What causes osteomyelitis?
There are several different ways to develop osteomyelitis. The first is for bacteria to travel through the bloodstream (bacteremia) and spread to the bone, causing an infection. This most often occurs when the patient has an infection elsewhere in the body, such as pneumonia or a urinary tract infection, that spreads through the blood to the bone.
An open wound over a bone can lead to osteomyelitis. An open fracture where the bone punctures through the skin is also a poten...