Amyloidosis is a group of metabolic familial or inherited, degenerative, and infectious disease processes, characterized by the abnormal protein folding and deposition of a complex substance composed of amyloid protein and fibrils (fine fibers). Amyloid A amyloidosis (AA) is the most common form of systemic amyloidosis worldwide. It is characterized by extracellular tissue deposition of fibrils that are composed of fragments of serum amyloid A (SAA) protein, a major acute-phase reactant protein, produced mainly by hepatocytes. There are several types of amyloid and the classification of amyloidosis is based on which amyloid protein is involved. A particular type of amyloidosis is designated by a capital A (for amyloid) followed by an abbreviation for the fibril protein. Twenty-three different fibril proteins are described in human amyloidosis with variable clinical features. In all forms of amyloidosis, the cell secretes the precursor protein in a soluble form that becomes insoluble at some tissue site, compromising organ function. Amyloidosis may develop in the course of a chronic inflammatory disease of either infectious or noninfectious origin, hereditary periodic fevers, neoplasms such as Hodgkin disease and renal cell carcinoma.1 Glomerular amyloidosis usually causes urinary excretion of protein. The disease is considered to be inherited in the Chinese Shar-Pei breed.
Rheumatoid arthritis
A chronic systemic disease, primarily of the joints, marked by inflammatory changes in the synovial membranes and articular structures, widespread fibrinoid degeneration of the collagen fibers in mesenchymal tissues, and by atrophy and rarefaction of bony structures. Causes are unknown, but autoimmune mechanisms have been implicated.
Juvenile chronic arthritis
Rheumatoid arthritis of children occurring in three major subtypes defined by the symptoms present during the first six months following onset: systemic-onset (Still's Disease, Juvenile-Onset), polyarticular-onset, and pauciarticular-onset. Only one subtype of juvenile rheumatoid arthritis (polyarticular-onset, rheumatoid factor-positive) clinically resembles adult rheumatoid arthritis and is considered its childhood equivalent.
Ankylosing spondylitis
A chronic inflammatory disease that predominantly affects young male individuals. Animals affected by this condition are in pain on arising, drag their legs and refuse to climb stairs.
Psoriasis
A common genetically determined, chronic, inflammatory skin disease characterized by rounded erythematous, dry, scaling patches. The lesions have a predilection for nails, scalp, genitalia, extensor surfaces, and the lumbosacral region. Accelerated epidermopoiesis is considered to be the fundamental pathologic feature in psoriasis.
Adult-Onset Still Disease
A form of systemic-onset rheumatoid arthritis in adults. It differs from classical rheumatoid arthritis in that it is more often marked by acute febrile onset, and generalized lymphadenopathy and hepatosplenomegaly are more prominent.
Crohn disease
A chronic and progressive inflammation of the ileum producing frequent bouts of diarrhea with abdominal pain, nausea, fever, and weight loss. |
Leprosy
A chronic communicable disease caused by Mycobacterium leprae; it occurs in tropical and subtropical regions and is characterized by inflamed nodules beneath the skin and wasting of body parts.
Osteomyelitis
Inflammation of bone and bone marrow that is usually caused by bacterial infections.
Tuberculosis
A bacterial infection that affects the lungs and is spread by inhalation of infected droplets.
Chronic bronchiectasis
| Persistent abnormal dilatation of the bronchi. |
Castleman disease
A rare illness that affects lymph nodes and other immune-cell structures of the body; also called giant lymph node hyperplasia.
Hodgkin disease
| A malignant disease characterized by progressive enlargement of the lymph nodes, spleen, and general lymphoid tissue. |