Localised amyloidosis

Parts of the body most commonly affected by localised amyloidosis?

Eye

Especially the conjunctiva (If deposits are symptomatic they may have to be excised).

Genito-urinary tract

Often presents as small pseudo tumors localized in the renal pelvis, ureters and bladder.

Skin

May present as what is called macular (flat) lesion or popular (raised) lesion. This is sometimes known as lichen amyloidosis which is often seen in the skin on thighs and forearms. Most often seen in people with a dark skin.

Upper airways and lungs

May also be seen in the respiratory system throat and lung tissue.

Gastro intestinal tract

Deposits may be found in the stomach or intestine.

Insulin injection sites

Occasionally localised amyloidosis is found in the skin around the injection sites of insulin dependent diabetics.

In localised amyloidosis deposits often appear as small nodules or tumors and may be treated by local incision. This may cure the disease however the amyloid may recur in the future in the same area of the body and need further excision, laser surgery or other localized treatment.

Symptoms

Symptoms may be vague and sometimes nonexistent. They will vary according to where the amyloid occurs. Localised amyloidosis may be found incidentally when procedures such as endoscopy or cystoscopy are being carried out.

  • Eye. Local deposits may affect the cornea affecting sight.
  • Genitourinary tract. Bladder irritation. Burning sensation on passing urine. Passing blood.
  • Skin. An Itch, raised annoying nodules on the skin.
  • Upper airways. Shortness of breath, cough, hoarseness.
  • Gastrointestinal Tract. Heart burn, constipation, bleeding in the gut

Diagnosis

  • Amyloidosis can only be definitively diagnosed through a tissue or organ biopsy.
  • In localized amyloidosis a tissue biopsy will involve taking a small piece of the tissue from the affected area.
  • The biopsy is then stained with a dye, Congo red, in the laboratory.
  • If amyloid is present, the biopsy will appear red under normal light and green (apple-green birefringence) under special polarized light

2nd procedure in the laboratory

  • Further testing on the biopsy to identify the type of amyloidosis by identifying the protein composition of the amyloid fibrils.
  • It is imperative to identify the “type” even though all information may point to the diagnosis being localized amyloidosis, as treatment is different for each type of amyloid.

To be certain that this is localized disease the usual work up tests will be performed to rule out systemic amyloidosis.

These may include:

  • A bone marrow biopsy
  • Free light chain tests
  • ECG
  • Echocardiography
  • Urine tests

Once the diagnosis has been established patients may undergo further tests and have consultations with other specialists to establish the extent of the amyloid deposition in the one area and form a treatment plan.

Treatment

Chemotherapy has no place in the treatment of Localised amyloidosis.

  • No treatment may be needed.
  • Symptomatic treatment including surgical excision or laser surgery.
  • Localised amyloidosis may be completely curable by removing the amyloid deposits by surgical excision. However, there is a chance it will grow back again into the same area.

The prognosis for localised amyloidosis is good.

Follow up will mainly by the relevant specialist treating the area affected by the amyloid protein. For example an eye surgeon, ENT specialist, respiratory physician, gastroenterologist, dermatologist or other specialists.

It is however important that patients are followed up on a regular basis by an amyloidosis clinical team to be certain that the localized disease does not become systemic.

CAA
This web site does not contain information on the most common form of localized amyloid angiopathy (CAA) which is totally unrelated to the local or systemic amyloidosis being discussed here.

Read The National Amyloidosis London’s patient information sheet on localized amyloidosis.