Renal amyloidosis overview: Difference between revisions

Jump to navigation Jump to search
Okamal (talk | contribs)
Aditya Ganti (talk | contribs)
No edit summary
 
(24 intermediate revisions by 2 users not shown)
Line 1: Line 1:
__NOTOC__
__NOTOC__
{{Renal Amyloidosis}}
{{Renal Amyloidosis}}
{{CMG}}; {{AE}}
{{CMG}} ; {{AE}} [[User:Okamal|Omer Kamal, M.D.]] [Mailto:okamal@bidmc.harvard.edu| <nowiki>[2]</nowiki>]
==Overview==
==Overview==
Nicolaus Fontanus was the first to describe [[amyloidosis]] based on the result of an autopsy while Rudolph Virchow was the first to introduce the term [[amyloidosis]]. [[Renal amyloidosis]] can be classified according to the site of [[amyloid]] deposition into glomerular, vascular, and tubular [[amyloidosis]]. Suggested mechanisms of renal involvement include abnormal [[protein]] production or hereditary mutation. If left untreated, [[renal amyloidosis]] may progress into end stage renal disease. Common complications include [[chronic renal failure]] and [[nephrotic syndrome]]. After a few years, [[renal amyloidosis]] eventually leads to end stage renal disease and it may be progressed  in presence of certain factors such as steroid administration, [[renal vein thrombosis]], [[Infection|infections]] and [[surgery]]. There is insufficient evidence to recommend routine screening for [[renal amyloidosis]]. Renal biopsy is the gold standard test for the diagnosis of [[Renal amyloidosis|renal diagnosis]]. The mainstay of treatment for renal amyloidosis is to decrease the production or increase clearing of [[amyloid]]. Pharmacologic medical therapies for renal amyloidosis include [[colchicine]], [[azathioprine]], [[Dimethyl sulfoxide|dimethylsulfoxide]], [[chlorambucil]], [[methotrexate]], [[cyclophosphamide]] and TNF-alpha antagonists (ie, [[etanercept]], [[infliximab]], and [[adalimumab]]).
==Historical Perspective==
==Historical Perspective==
* In 1639, Nicolaus Fontanus [[Autopsy|autopsied]] a young man who had [[Ascites|ascitis]], [[jaundice]], [[liver abscess]] and [[splenomegaly]] and his report has been the first description of amyloidosis.<ref name="pmid21838413">{{cite journal |vauthors=Kyle RA |title=Amyloidosis: a brief history |journal=Amyloid |volume=18 Suppl 1 |issue= |pages=6–7 |date=June 2011 |pmid=21838413 |doi=10.3109/13506129.2011.574354001 |url=}}</ref>
Nicolaus Fontanus was the first to describe [[amyloidosis]] based on the result of an autopsy while Rudolph Virchow was the first to introduce the term [[amyloidosis]].
* In 1854, Rudolph Virchow introduced the term of [[amyloid]] as an macroscopic abnormality in some tissues.<ref name="pmid10940217">{{cite journal |vauthors=Sipe JD, Cohen AS |title=Review: history of the amyloid fibril |journal=J. Struct. Biol. |volume=130 |issue=2-3 |pages=88–98 |date=June 2000 |pmid=10940217 |doi=10.1006/jsbi.2000.4221 |url=}}</ref>
 
*In 1969, Finnish-type familial amyloidosis (FAF) was first described as one of the causes of renal amyloidosis.<ref name="pmid26019848">{{cite journal |vauthors=Yamanaka S, Miyazaki Y, Kasai K, Ikeda S, Kiuru-Enari S, Hosoya T |title=Hereditary renal amyloidosis caused by a heterozygous G654A gelsolin mutation: a report of two cases |journal=Clin Kidney J |volume=6 |issue=2 |pages=189–93 |date=April 2013 |pmid=26019848 |pmc=4432447 |doi=10.1093/ckj/sft007 |url=}}</ref>


==Classification==
==Classification==
 
[[Renal amyloidosis]] can be classified according to the site of [[amyloid]] deposition into glomerular, vascular, and tubular [[amyloidosis]].
Renal amyloidosis may be classified according to site of amyloid deposition into 3 subtypes:<ref name="pmid21360109">{{cite journal |vauthors=Bilginer Y, Akpolat T, Ozen S |title=Renal amyloidosis in children |journal=Pediatr. Nephrol. |volume=26 |issue=8 |pages=1215–27 |date=August 2011 |pmid=21360109 |pmc=3119800 |doi=10.1007/s00467-011-1797-x |url=}}</ref>
*Glomerular amyloid deposition (more common and have a poorer prognosis)
*Vascular amyloid deposition
*Tubular amyloid deposition
Renal amyloidosis may be classified according to type of amyloidogenic protein into 3 subtypes:<ref name="pmid23704299">{{cite journal |vauthors=Said SM, Sethi S, Valeri AM, Leung N, Cornell LD, Fidler ME, Herrera Hernandez L, Vrana JA, Theis JD, Quint PS, Dogan A, Nasr SH |title=Renal amyloidosis: origin and clinicopathologic correlations of 474 recent cases |journal=Clin J Am Soc Nephrol |volume=8 |issue=9 |pages=1515–23 |date=September 2013 |pmid=23704299 |pmc=3805078 |doi=10.2215/CJN.10491012 |url=}}</ref>
{| class="wikitable"
!
!Amyloidosis type
!Amyloidogenic protein
|-
| rowspan="4" |Common types
| rowspan="3" |AL/AHL/AH
(Primary amyloidosis)
|Ig light chains (AL)
|-
|Fragments of Ig heavy chains and light chains (AHL)
|-
|Fragments of heavy chains only (AH)
|-
|AA
(Secondary amyloidosis)
|Serum amyloid A
|-
| rowspan="6" |Rare types
|AFib
|Fibrinogen A α chain
|-
|AApo AI/AII/AIV
|Apo AI, Apo AII, or Apo AIV
|-
|ATTR
|Transthyretin
|-
|ALys
|Lysozyme
|-
|AGel
|Gelsolin
|-
|ALECT2
|Leukocyte chemotactic factor 2
|}


==Pathophysiology==
==Pathophysiology==
 
Suggested mechanisms of renal involvement include abnormal [[protein]] production or hereditary mutation.
===Pathogenesis===
*In systemic amyloidosis (AL/AH/AHL is much more common than AA) kidney is the most frequently involved organ.<ref name="pmid23704299">{{cite journal |vauthors=Said SM, Sethi S, Valeri AM, Leung N, Cornell LD, Fidler ME, Herrera Hernandez L, Vrana JA, Theis JD, Quint PS, Dogan A, Nasr SH |title=Renal amyloidosis: origin and clinicopathologic correlations of 474 recent cases |journal=Clin J Am Soc Nephrol |volume=8 |issue=9 |pages=1515–23 |date=September 2013 |pmid=23704299 |pmc=3805078 |doi=10.2215/CJN.10491012 |url=}}</ref>
*In renal amyloidosis, the mechanisms of amyloidogenesis may include:<ref name="pmid25852856">{{cite journal |vauthors=Khalighi MA, Dean Wallace W, Palma-Diaz MF |title=Amyloid nephropathy |journal=Clin Kidney J |volume=7 |issue=2 |pages=97–106 |date=April 2014 |pmid=25852856 |pmc=4377792 |doi=10.1093/ckj/sfu021 |url=}}</ref>
**Abnormal protein production
**Overproduction wild-type proteins
**Decreased excretion of wild-type proteins
**Hereditary mutation
*In multiple myeloma, the cast nephropathy in distal tubules of nephrons results in renal impairment and deposition of AL amyloid protein in glomeruli can cause massive fibrillar involvement.<ref name="pmid27942184">{{cite journal |vauthors=Hajra A, Bandyopadhyay D |title=An interesting case of renal amyloidosis |journal=Indian J Nephrol |volume=26 |issue=6 |pages=467–469 |date=2016 |pmid=27942184 |pmc=5131391 |doi=10.4103/0971-4065.177143 |url=}}</ref>
 
==Microscopic Pathology==
Microscopic Pathology of all types of amyloid after Congo red dye staining include: <ref name="pmid25852856">{{cite journal |vauthors=Khalighi MA, Dean Wallace W, Palma-Diaz MF |title=Amyloid nephropathy |journal=Clin Kidney J |volume=7 |issue=2 |pages=97–106 |date=April 2014 |pmid=25852856 |pmc=4377792 |doi=10.1093/ckj/sfu021 |url=}}</ref>
* Orange-red appearance by normal light microscopy
* Apple-green birefringence upon polarized light
For more general information about amyloidosis, click [[Amyloidosis|'''here''']].


==Causes==
==Causes==
===Common Causes===
Most common causes of renal [[amyloidosis]] include primary and secondary [[amyloidosis]]. Other causes include [[transthyretin]] and [[fibrinogen]] [[amyloid]] deposition.
In renal amyloidosis, most common causes include:<ref name="pmid23704299">{{cite journal |vauthors=Said SM, Sethi S, Valeri AM, Leung N, Cornell LD, Fidler ME, Herrera Hernandez L, Vrana JA, Theis JD, Quint PS, Dogan A, Nasr SH |title=Renal amyloidosis: origin and clinicopathologic correlations of 474 recent cases |journal=Clin J Am Soc Nephrol |volume=8 |issue=9 |pages=1515–23 |date=September 2013 |pmid=23704299 |pmc=3805078 |doi=10.2215/CJN.10491012 |url=}}</ref>
* Primary (AL) amyloidosis
* Secondary (AA) amyloidosis:
** [[Tuberculosis|TB]]
** [[Familial mediterranean fever|Familial mediterranean fever (FMF)]]
** [[Rheumatoid arthritis|Rheumatoid arthritis (RA)]]
** [[Multiple myeloma]]
 
===Less Common Causes===
In renal amyloidosis, less common causes include:<ref name="pmid24497558">{{cite journal |vauthors=Mahmood S, Palladini G, Sanchorawala V, Wechalekar A |title=Update on treatment of light chain amyloidosis |journal=Haematologica |volume=99 |issue=2 |pages=209–21 |date=February 2014 |pmid=24497558 |pmc=3912950 |doi=10.3324/haematol.2013.087619 |url=}}</ref>
*.Hereditary amyloidosis due to amyloidogenic [[Mutation|mutations]]:
** [[Transthyretin|Transthyretin (TTR)]] (most common [[inherited]] [[mutation]])
** [[Fibrinogen]]
** [[Apolipoprotein A1]]
** [[Apolipoprotein A2]]
** [[Lysozyme]]
** [[Gelsolin]] [[Gene|genes]]


==Differentiating Renal amyloidosis from Other Diseases==
==Differentiating Renal amyloidosis from Other Diseases==


==Epidemiology and Demographics==
==Epidemiology and Demographics==
===Incidence===
The [[incidence]] is 97 to 140 cases per 100,000 individuals. The incidence of renal amyloidosis increases with age; the median age at diagnosis is 65 years.
The incidence is 9.7 to 14.0 cases per million person-years.<ref name="pmid29748430">{{cite journal |vauthors=Quock TP, Yan T, Chang E, Guthrie S, Broder MS |title=Epidemiology of AL amyloidosis: a real-world study using US claims data |journal=Blood Adv |volume=2 |issue=10 |pages=1046–1053 |date=May 2018 |pmid=29748430 |pmc=5965052 |doi=10.1182/bloodadvances.2018016402 |url=}}</ref>
 
===Prevalence===
The prevalence of AL amyloidosis was 40.5 in 2015, an annual percentage change (APC) of 12%. <ref name="pmid29748430" />
 
===Mortality rate===
*AL has higher mortality than AA type<ref name="pmid18184882">{{cite journal |vauthors=Bollée G, Guery B, Joly D, Snanoudj R, Terrier B, Allouache M, Mercadal L, Peraldi MN, Viron B, Fumeron C, Elie C, Fakhouri F |title=Presentation and outcome of patients with systemic amyloidosis undergoing dialysis |journal=Clin J Am Soc Nephrol |volume=3 |issue=2 |pages=375–81 |date=March 2008 |pmid=18184882 |pmc=2390937 |doi=10.2215/CJN.02470607 |url=}}</ref>
 
===Age===
*In renal amyloidosis, is usually first diagnosed in average age of 65 years and it is uncommon before age of 40.<ref name="pmid25852856">{{cite journal |vauthors=Khalighi MA, Dean Wallace W, Palma-Diaz MF |title=Amyloid nephropathy |journal=Clin Kidney J |volume=7 |issue=2 |pages=97–106 |date=April 2014 |pmid=25852856 |pmc=4377792 |doi=10.1093/ckj/sfu021 |url=}}</ref><ref name="pmid27942184">{{cite journal |vauthors=Hajra A, Bandyopadhyay D |title=An interesting case of renal amyloidosis |journal=Indian J Nephrol |volume=26 |issue=6 |pages=467–469 |date=2016 |pmid=27942184 |pmc=5131391 |doi=10.4103/0971-4065.177143 |url=}}</ref>
 
===Race===
*There is no racial predilection to renal amyloidosis.
===Gender===
*In renal amyloidosis, the male to female ratio is approximately 2 to 1.<ref name="pmid25852856">{{cite journal |vauthors=Khalighi MA, Dean Wallace W, Palma-Diaz MF |title=Amyloid nephropathy |journal=Clin Kidney J |volume=7 |issue=2 |pages=97–106 |date=April 2014 |pmid=25852856 |pmc=4377792 |doi=10.1093/ckj/sfu021 |url=}}</ref>
 
===Region===
*ALECT2 is more frequent in the United States area.<ref name="pmid23704299">{{cite journal |vauthors=Said SM, Sethi S, Valeri AM, Leung N, Cornell LD, Fidler ME, Herrera Hernandez L, Vrana JA, Theis JD, Quint PS, Dogan A, Nasr SH |title=Renal amyloidosis: origin and clinicopathologic correlations of 474 recent cases |journal=Clin J Am Soc Nephrol |volume=8 |issue=9 |pages=1515–23 |date=September 2013 |pmid=23704299 |pmc=3805078 |doi=10.2215/CJN.10491012 |url=}}</ref>
*AFib cases are most reported in Europe countries.


==Risk Factors==
==Risk Factors==
The most potent risk factor in the development of Renal amyloidosis are genetic . Other risk factors include age.<ref name="pmid19790131" />
Common risk factors in the development of renal amyloidosis may be environmental and genetic such as heterozygous mutations in the genes for [[lysozyme]], [[Apolipoprotein A1|apolipoprotein AI]], [[Apolipoprotein A2|apolipoprotein AII]], or [[Fibrinogen alpha chain|fibrinogen]] A alpha-chain.
===Common Risk Factors===
*Common risk factors in the development of Renal amyloidosis may be environmental and genetic.
*Common risk factors in the development of Renal amyloidosis include:<ref name="pmid19790131">{{cite journal |vauthors=Obici L, Raimondi S, Lavatelli F, Bellotti V, Merlini G |title=Susceptibility to AA amyloidosis in rheumatic diseases: a critical overview |journal=Arthritis Rheum. |volume=61 |issue=10 |pages=1435–40 |date=October 2009 |pmid=19790131 |doi=10.1002/art.24735 |url=}}</ref><ref name="pmid10036584">{{cite journal |vauthors=Booth DR, Booth SE, Gillmore JD, Hawkins PN, Pepys MB |title=SAA1 alleles as risk factors in reactive systemic AA amyloidosis |journal=Amyloid |volume=5 |issue=4 |pages=262–5 |date=December 1998 |pmid=10036584 |doi= |url=}}</ref>
**Age
**SAA1
**Point mutations in the ''apoAI'' gene
**Point mutations in the ''apoAII'' gene
**Heterozygous mutations in the genes for lysozyme, apolipoprotein AI, apolipoprotein AII, or fibrinogen A alpha-chain


==Screening==
==Screening==
There is insufficient evidence to recommend routine screening for renal amyloidosis.
There is insufficient evidence to recommend routine screening for [[renal amyloidosis]].


==Natural History, Complications, and Prognosis==
==Natural History, Complications, and Prognosis==
 
If left untreated, [[renal amyloidosis]] may progress into end stage renal disease. Common complications include chronic renal failure and nephrotic syndrome. After a few years, [[renal amyloidosis]] eventually leads to end stage renal disease and it may be accelerated by some factors such as steroid administration, [[renal vein thrombosis]], [[Infection|infections]] and [[surgery]].
===Natural History===
*If renal amyloidosis left untreated it usually manifests as nephrotic range proteinuria and then progresses to acute kidney injury and then end stage renal disease.<ref name="pmid27840752">{{cite journal |vauthors=Lohani S, Schuiteman E, Garg L, Yadav D, Zarouk S |title=Apolipoprotein C-II Deposition Amyloidosis: A Potential Misdiagnosis as Light Chain Amyloidosis |journal=Case Rep Nephrol |volume=2016 |issue= |pages=8690642 |date=2016 |pmid=27840752 |pmc=5093243 |doi=10.1155/2016/8690642 |url=}}</ref>
 
===Complications===
*Common complications of renal amyloidosis include:<ref name="pmid21360109">{{cite journal |vauthors=Bilginer Y, Akpolat T, Ozen S |title=Renal amyloidosis in children |journal=Pediatr. Nephrol. |volume=26 |issue=8 |pages=1215–27 |date=August 2011 |pmid=21360109 |pmc=3119800 |doi=10.1007/s00467-011-1797-x |url=}}</ref><ref name="pmid27942184">{{cite journal |vauthors=Hajra A, Bandyopadhyay D |title=An interesting case of renal amyloidosis |journal=Indian J Nephrol |volume=26 |issue=6 |pages=467–469 |date=2016 |pmid=27942184 |pmc=5131391 |doi=10.4103/0971-4065.177143 |url=}}</ref>
**Proteinuria (32%)
**Nephrotic syndrome (40%)
**Chronic renal failure (28%)
**Hypoalbuminemia
 
===Prognosis===
*After a few years, renal amyloidosis eventually leads to end stage renal disease and it may be accelerated by some factors such as:<ref name="pmid10231478">{{cite journal |vauthors=Kaaroud H, Ben Moussa F, Goucha R, Abderrahim E, Ben Hamida F, Ben Hamida F, Ben Hamida F, Kheder A, Ben Miaz H |title=Influence of surgery on renal amyloidosis |journal=Kidney Int. |volume=55 |issue=5 |pages=2117–2133 |date=May 1999 |pmid=10231478 |doi=10.1046/j.1523-1755.1999.00455.x |url=}}</ref>
**Steroid administration
**Renal vein thrombosis
**Infections
**Surgery


==Diagnosis==
==Diagnosis==
===Diagnostic Study of Choice===
===Diagnostic Study of Choice===
Renal biopsy is the gold standard test for the diagnosis of [[Renal amyloidosis|renal diagnosis]]


===History and Symptoms===
===History and Symptoms===
The majority of patients with renal amyloidosis have [[proteinuria]]. [[Swelling]] is very common in lower limbs. [[Numbness]] or tingling in hands or feet ([[carpal tunnel syndrome]]) is a less common finding.


===Physical Examination===
===Physical Examination===
Physical examination of patients with [[renal amyloidosis]] is usually remarkable for [[swelling]], [[hepatosplenomegaly]], facial or neck [[purpura]] and [[macroglossia]]. Fatigue and unintentional [[weight loss]], are common in patients with AL [[amyloidosis]]. [[Tachycardia]]/[[bradycardia]] depends on the accompanying [[complication]]. Pulmonary fine [[crackles]], faint pulmonary auscultation, suggestive of [[pleural effusion]], decreased [[tactile fremitus]] and dull percussion.


===Laboratory Findings===
===Laboratory Findings===
In patients with secondary [[amyloidosis]], [[urinalysis]] should be routinely examined. Laboratory findings consistent with the diagnosis of [[renal amyloidosis]] include [[proteinuria]] and increased serum [[creatinine]]


===Electrocardiogram===
===Electrocardiogram===
There are no ECG findings associated with [[renal amyloidosis]].


===X-ray===
===X-ray===
There are no definitive findings on x-ray associated with [[renal amyloidosis]].


===Echocardiography and Ultrasound===
===Echocardiography and Ultrasound===
There are no echocardiography/ultrasound findings associated with [[renal amyloidosis]]


===CT scan===
===CT scan===
There are no CT scan findings associated with [[renal amyloidosis]]


===MRI===
===MRI===
There are no MRI findings associated with [[renal amyloidosis]].


===Other Imaging Findings===
===Other Imaging Findings===
There are no other imaging findings associated with [[renal amyloidosis]]


===Other Diagnostic Studies===
===Other Diagnostic Studies===
Kidney biopsy can represent amyloid deposition as [[vascular]], [[tubulo-interstitial]] and/or [[glomerular]] deposits. All types of [[amyloidogenic]] proteins show affinity for Congo red dye.


==Treatment==
==Treatment==
===Medical Therapy===
===Medical Therapy===
 
The mainstay of treatment for renal amyloidosis is to decrease the production or increase clearing of [[amyloid]]. Pharmacologic medical therapies for renal amyloidosis include [[colchicine]], [[azathioprine]], [[Dimethyl sulfoxide|dimethylsulfoxide]], [[chlorambucil]], [[methotrexate]], [[cyclophosphamide]] and TNF-alpha antagonists (ie, [[etanercept]], [[infliximab]], and [[adalimumab]]).
=== Interventions ===


===Surgery===
===Surgery===
In [[renal amyloidosis]], [[surgery]] is usually reserved for patients developed with end stage renal disease. The patients with [[renal amyloidosis]] are good candidates for transplantation. In primary amyloidosis, [[Kidney transplantation|renal transplantation]] is considered and it will improve long-term survival and quality of life.


===Primary Prevention===
===Primary Prevention===
There are no established measures for the primary prevention of [[renal amyloidosis]].


===Secondary Prevention===
===Secondary Prevention===
 
Treatment of the primary disease and underlying cause will provide favorable renal outcome.{{WikiDoc Help Menu}}
==References==
{{reflist|2}}
 
{{WikiDoc Help Menu}}
{{WikiDoc Sources}}
{{WikiDoc Sources}}
[[Category: (name of the system)]]
[[Category: (name of the system)]]

Latest revision as of 18:32, 8 August 2018

Renal amyloidosis Microchapters

Home

Patient Information

Overview

Historical Perspective

Classification

Pathophysiology

Causes

Differentiating Renal amyloidosis from other Diseases

Epidemiology and Demographics

Risk Factors

Screening

Natural History, Complications and Prognosis

Diagnosis

Diagnostic Study of Choice

History and Symptoms

Physical Examination

Laboratory Findings

Electrocardiogram

Chest X Ray

Echocardiography or Ultrasound

CT

MRI

Other Imaging Findings

Other Diagnostic Studies

Treatment

Medical Therapy

Surgery

Primary Prevention

Secondary Prevention

Cost-Effectiveness of Therapy

Future or Investigational Therapies

Case Studies

Case #1

Template:Renal amyloidosis On the Web

Most recent articles

cited articles

Review articles

CME Programs

Powerpoint slides

Images

American Roentgen Ray Society Images of Renal amyloidosis overview

All Images
X-rays
Echo & Ultrasound
CT Images
MRI

Ongoing Trials at Clinical Trials.gov

US National Guidelines Clearinghouse

NICE Guidance

FDA on Renal amyloidosis overview

CDC on Renal amyloidosis overview

Renal amyloidosis overview in the news

Blogs on Renal amyloidosis overview

Directions to Hospitals Treating Cystic fibrosis

Risk calculators and risk factors for Renal amyloidosis overview

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] ; Associate Editor(s)-in-Chief: Omer Kamal, M.D. [2]

Overview

Nicolaus Fontanus was the first to describe amyloidosis based on the result of an autopsy while Rudolph Virchow was the first to introduce the term amyloidosis. Renal amyloidosis can be classified according to the site of amyloid deposition into glomerular, vascular, and tubular amyloidosis. Suggested mechanisms of renal involvement include abnormal protein production or hereditary mutation. If left untreated, renal amyloidosis may progress into end stage renal disease. Common complications include chronic renal failure and nephrotic syndrome. After a few years, renal amyloidosis eventually leads to end stage renal disease and it may be progressed in presence of certain factors such as steroid administration, renal vein thrombosis, infections and surgery. There is insufficient evidence to recommend routine screening for renal amyloidosis. Renal biopsy is the gold standard test for the diagnosis of renal diagnosis. The mainstay of treatment for renal amyloidosis is to decrease the production or increase clearing of amyloid. Pharmacologic medical therapies for renal amyloidosis include colchicine, azathioprine, dimethylsulfoxide, chlorambucil, methotrexate, cyclophosphamide and TNF-alpha antagonists (ie, etanercept, infliximab, and adalimumab).

Historical Perspective

Nicolaus Fontanus was the first to describe amyloidosis based on the result of an autopsy while Rudolph Virchow was the first to introduce the term amyloidosis.

Classification

Renal amyloidosis can be classified according to the site of amyloid deposition into glomerular, vascular, and tubular amyloidosis.

Pathophysiology

Suggested mechanisms of renal involvement include abnormal protein production or hereditary mutation.

Causes

Most common causes of renal amyloidosis include primary and secondary amyloidosis. Other causes include transthyretin and fibrinogen amyloid deposition.

Differentiating Renal amyloidosis from Other Diseases

Epidemiology and Demographics

The incidence is 97 to 140 cases per 100,000 individuals. The incidence of renal amyloidosis increases with age; the median age at diagnosis is 65 years.

Risk Factors

Common risk factors in the development of renal amyloidosis may be environmental and genetic such as heterozygous mutations in the genes for lysozyme, apolipoprotein AI, apolipoprotein AII, or fibrinogen A alpha-chain.

Screening

There is insufficient evidence to recommend routine screening for renal amyloidosis.

Natural History, Complications, and Prognosis

If left untreated, renal amyloidosis may progress into end stage renal disease. Common complications include chronic renal failure and nephrotic syndrome. After a few years, renal amyloidosis eventually leads to end stage renal disease and it may be accelerated by some factors such as steroid administration, renal vein thrombosis, infections and surgery.

Diagnosis

Diagnostic Study of Choice

Renal biopsy is the gold standard test for the diagnosis of renal diagnosis

History and Symptoms

The majority of patients with renal amyloidosis have proteinuria. Swelling is very common in lower limbs. Numbness or tingling in hands or feet (carpal tunnel syndrome) is a less common finding.

Physical Examination

Physical examination of patients with renal amyloidosis is usually remarkable for swelling, hepatosplenomegaly, facial or neck purpura and macroglossia. Fatigue and unintentional weight loss, are common in patients with AL amyloidosis. Tachycardia/bradycardia depends on the accompanying complication. Pulmonary fine crackles, faint pulmonary auscultation, suggestive of pleural effusion, decreased tactile fremitus and dull percussion.

Laboratory Findings

In patients with secondary amyloidosis, urinalysis should be routinely examined. Laboratory findings consistent with the diagnosis of renal amyloidosis include proteinuria and increased serum creatinine

Electrocardiogram

There are no ECG findings associated with renal amyloidosis.

X-ray

There are no definitive findings on x-ray associated with renal amyloidosis.

Echocardiography and Ultrasound

There are no echocardiography/ultrasound findings associated with renal amyloidosis

CT scan

There are no CT scan findings associated with renal amyloidosis

MRI

There are no MRI findings associated with renal amyloidosis.

Other Imaging Findings

There are no other imaging findings associated with renal amyloidosis

Other Diagnostic Studies

Kidney biopsy can represent amyloid deposition as vascular, tubulo-interstitial and/or glomerular deposits. All types of amyloidogenic proteins show affinity for Congo red dye.

Treatment

Medical Therapy

The mainstay of treatment for renal amyloidosis is to decrease the production or increase clearing of amyloid. Pharmacologic medical therapies for renal amyloidosis include colchicine, azathioprine, dimethylsulfoxide, chlorambucil, methotrexate, cyclophosphamide and TNF-alpha antagonists (ie, etanercept, infliximab, and adalimumab).

Surgery

In renal amyloidosis, surgery is usually reserved for patients developed with end stage renal disease. The patients with renal amyloidosis are good candidates for transplantation. In primary amyloidosis, renal transplantation is considered and it will improve long-term survival and quality of life.

Primary Prevention

There are no established measures for the primary prevention of renal amyloidosis.

Secondary Prevention

Treatment of the primary disease and underlying cause will provide favorable renal outcome. Template:WikiDoc Sources