The Complete Clinical Course Of Amyloidosis
Clinical Manifestation Of Amyloidosis
A General Overview
This term refers to a group of disorders characterized by the deposition of amyloid which is a homogenous eosinophilic material in several tissues in the body.
- Without any detectable underlying cause associated with myeloma
- Chronic infections
- Rheumatoid disease
- Lymphoma and other neoplasms
- Heredo-familial Mediterranean fever
- Local amyloidosis- Skin, joints, tendon, nerves and other structures
- Senile amyloidosis.
Common sites of involvement in amyloidosis
- Gastrointestinal tract
- Skeletal and visceral muscles
- Joints, tendons
- Adrenal cortex
- Other glands
Note that considerable overlap may occur between the two forms.
Patient With Amyloidosis
Systemic Amyloidosis: Clinical features depend on the tissue involved. Since the kidneys are affected most frequently in secondary amyloidosis, 60% cases present with nephritic syndrome. The rest may be asymptomatic. It is the common cause of death in chronic renal failure.
The heart is affected in 80-90% of cases of primary amyloidosis and this results in restrictive congestive cardiomyopathy, cardiac failure and arrhythmias. Sudden death may occur.
Gastrointestinal involvement : Macroglossia may interfere with deglutition and respiration. Involvement of the intestines produces diarrhea malabsorption, intestinal obstruction and gastrointestinal bleeding.
Liver is commonly involved in both types of amyloidosis. The organ is enlarged and firm but functional derangement is not marked.
Spleen is commonly enlarged in seconday amyloidosis and this leads to hypofunction of the gland.
Respiratory tract: Amyloid deposition may occur in the respiratory passages or in the lung parenchyma.
Nervous involvement: Common presentations are peripheral neuropathy and carpal tunnel syndrome. Primary cerebrovascular amyloidosis may occur in which amyloid deposits occur in the arteries and arterioles as well as adventitia of the veins and venules.
Nodular masses of amyloid may occur in the around joints and tendons, particularly around the glenohumeral joints. Large deposits may occur giving rise to the “shoulder pad sign”
Arthralgia and arthritis resembling rheumatoid arthritis may occur. Affection of the skin manifests as lichenoid plaques, nodules or purpura around the orbits.
In 80-90% of persons above the age of 80 years, amyloidosis of the heart may occur (senile cardiac amyloidosis).
Prognosis Of Amyloidosis
Diagnosis, Prognosis And Treatment
Amyloidosis is confirmed by biopsy of appropriate tissues. The rectal mucosa is commonly involved in primary amyloidosis and therefore rectal biopsy is a rewarding procedure. Renal biopsy is usually positive when there is proteinuria. Amyloid deposits can be demonstrated in the gingival mucosa when gums are clinically abnormal. Electron microscopy of urine and synovial fluid may reveal amyloid fibrils.
Systemic amyloidosis is always fatal, death is due to renal or cardiac failure within 1-2 years of diagnosis. Progress of amyloidosis can be arrested and the lesions may even regress with treatment of the underlying condition.
Treatment of the underlying cause is instituted wherever a cause can be detected. Cytotoxic drugs are sometimes beneficial in primary and reactive amyloidosis, but not in all cases.
© 2014 Funom Theophilus Makama