ALECT 2 Amyloidosis
Amyloidosis is the name given to a group of more than 30 complicated, rare diseases that result from the abnormal deposition of various misfolded proteins as amyloid in different tissues and organs of the body. Without treatment these proteins build up overtime leading to organ failure. (See section “What is amyloidosis” and “living with amyloidosis”)
ALECT2 is one of the most recently described types of amyloidosis.
It was first identified in 2008 when a 61-year-old woman had her kidney removed for what was thought to be kidney cancer. She had been diagnosed with amyloidosis “of unknown type” some years before and had developed progressive kidney failure.
Analysis of the amyloid fibrils from the kidney removed at surgery, identified the protein called leukocyte chemotactic factor 2 (LECT2)
For many years ALECT2 may have been misdiagnosed or given the label “of unknown type”.
It is now being diagnosed in increasing numbers around the world.
5 cases have been diagnosed in Australia to date.
What does the protein LECT2 do?
LECT2 is a normal bloodstream protein mainly produced in the liver but Its true biological role is still being defined. It is thought it may be involved in auto immune response and may play a role in white blood cell migration and stimulation of bone cell growth and repair.
Before the discovery of its relationship with amyloid, ALECT2 had never been known to have amyloid forming potential.
What causes ALECT2 amyloidosis?
- The cause is unknown
- It usually occurs in people over the age of 60 but has been diagnosed in younger people
- It is not an inherited type of amyloidosis but does tend to occur in clusters with a high incidence in the elderly Hispanic population. It is also seen in other ethnic groups but the burden of disease seems to be less in Caucasians.
ALECT2 is considered a systemic form of amyloidosis.
Amyloid deposits may be found in the liver, spleen, colon, and adrenal glands but in most cases the kidney and liver are the predominant organs affected.
- The kidney
- Patients often present with chronic progressive kidney failure with low level/mild proteinuria
- Loss of appetite
- swelling in ankles and legs
- The liver
- Alect2 affecting the liver is often found incidentally at biopsy.
- It can cause raised alkaline phosphatase also seen in other liver diseases.
Patients diagnosed with ALECT2 are also often found to have chronic hypertension and diabetes.
Diagnosing ALECT 2 Amyloidosis
To ensure the correct treatment is given It is imperative that this disease is correctly typed. After a diagnosis of amyloidosis has been verified through a tissue or organ biopsy stained with Congo red dye the biopsy will undergo further testing to identify the type of amyloidosis.
Other tests will also be ordered. These may include:
- DNA to make certain the patient’s disease is not of a hereditary type.
- Blood tests, x-rays, scans to pinpoint which organs are involved and to what degree.
Refer to section on “What is amyloidosis”
Once tests have established the type of amyloidosis and the extent of organ involvement a treatment plan will be made in consultation with the patient.
- Chemotherapy is not indicated for ALECT2 amyloidosis.
- At this time there is no specific treatment to slow or stop the production of the amyloid in ALECT2.
- Supportive care is the main stay of treatment.
Alect2 affecting the liver may not require treatment.
Abnormal kidney function caused by the infiltration of the amyloid protein may result in fluid retention due to difficulty in passing urine.
Fluid retention can result in:
- swelling in the legs
- difficulty breathing because of heart failure.
Fluid balance is therefore very important.
- Patients may be asked to keep a record of their weight
- Medications such as diuretics many be recommended to help manage urine production and body fluid levels.
- Dialysis may be indicated for those with kidney failure.
- Kidney transplant may be suggested in selected patients.
A renal physician familiar with the treatment of amyloidosis is usually the primary specialist in the care of patients with ALECT2.
Refer to sections “What is Amyloidosis” and “Living with Amyloidosis”
See also the Amyloidosis Patient Information Site at the UK’s National Amyloidosis Centre
Answers to Questions about LECT2 Amyloidosis