Amyloidosis

Amyloidosis
Amyloidosis symptoms are often vague and require different physician specialists for diagnosis. Telltale symptoms may include an enlarged tongue (macroglossia) or bruising around the eyes (purpura)[1]
SpecialtyInternal medicine
SymptomsFeeling tired, weight loss, swelling of the legs, shortness of breath, bleeding, feeling light headed with standing[2]
Usual onset55–65 years old[2]
CausesGenetic or acquired[3]
Diagnostic methodTissue biopsy[2]
TreatmentSupportive care, directed at the underlying cause, dialysis, organ transplantation[3]
PrognosisImproved with treatment[3]
Frequency3–13 per million per year (AL amyloidosis)[2]
Deaths1 per 1,000 people (developed world)[3]

Amyloidosis is a group of diseases in which abnormal proteins, known as amyloid fibrils, build up in tissue.[4] There are several non-specific and vague signs and symptoms associated with amyloidosis.[5] These include fatigue, peripheral edema, weight loss, shortness of breath, palpitations, and feeling faint with standing.[5] In AL amyloidosis, specific indicators can include enlargement of the tongue and periorbital purpura.[5] In wild-type ATTR amyloidosis, non-cardiac symptoms include: bilateral carpal tunnel syndrome, lumbar spinal stenosis, biceps tendon rupture, small fiber neuropathy, and autonomic dysfunction.[5]

There are about 36 different types of amyloidosis, each due to a specific protein misfolding.[6] Within these 36 proteins, 19 are grouped into localized forms, 14 are grouped as systemic forms, and three proteins can identify as either.[6] These proteins can become irregular due to genetic effects, as well as through acquired environmental factors.[6] The four most common types of systemic amyloidosis are light chain (AL), inflammation (AA), dialysis-related (Aβ2M), and hereditary and old age (ATTR and wild-type transthyretin amyloid[7]).[2]

Diagnosis may be suspected when protein is found in the urine, organ enlargement is present, or problems are found with multiple peripheral nerves and it is unclear why.[2] Diagnosis is confirmed by tissue biopsy.[2] Due to the variable presentation, a diagnosis can often take some time to reach.[3]

Treatment is geared towards decreasing the amount of the involved protein.[2] This may sometimes be achieved by determining and treating the underlying cause.[2] AL amyloidosis occurs in about 3–13 per million people per year and AA amyloidosis in about two per million people per year.[2] The usual age of onset of these two types is 55 to 60 years old.[2] Without treatment, life expectancy is between six months and four years.[2] In the developed world about one per 1,000 deaths are from systemic amyloidosis.[3] Amyloidosis has been described since at least 1639.[2]

  1. ^ "Amyloidosis Awareness" (PDF). amyloidaware.com. Amyloidosis Support Groups. 1 March 2022. Retrieved 15 June 2024.
  2. ^ a b c d e f g h i j k l m Hazenberg BP (May 2013). "Amyloidosis: a clinical overview" (PDF). Rheumatic Disease Clinics of North America. 39 (2): 323–345. doi:10.1016/j.rdc.2013.02.012. PMID 23597967. S2CID 215069282.
  3. ^ a b c d e f Pepys MB (2006). "Amyloidosis". Annual Review of Medicine. 57: 223–241. doi:10.1146/annurev.med.57.121304.131243. PMID 16409147.
  4. ^ "AL amyloidosis". rarediseases.info.nih.gov. Genetic and Rare Diseases Information Center (GARD). Archived from the original on 24 April 2017. Retrieved 22 April 2017.
  5. ^ a b c d Cite error: The named reference Gertz_2020 was invoked but never defined (see the help page).
  6. ^ a b c Picken MM (2020). "The Pathology of Amyloidosis in Classification: A Review". Acta Haematologica. 143 (4): 322–334. doi:10.1159/000506696. PMID 32392555. S2CID 218600304.
  7. ^ Ando Y, Coelho T, Berk JL, Cruz MW, Ericzon BG, Ikeda S, et al. (February 2013). "Guideline of transthyretin-related hereditary amyloidosis for clinicians". Orphanet Journal of Rare Diseases. 8: 31. doi:10.1186/1750-1172-8-31. PMC 3584981. PMID 23425518.