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Upper limbs

• Carpal tunnel syndrome
• Peripheral neuropathy
• Nail dystrophy

Gastrointestinal

• Reduced appetite
• Bloating
• Altered bowel habits( diarrhoea or constipation)

Lower limbs

• Oedema
• Peripheral neuropathy
• Weakness
• Nail dystrophy

Head and neck

• Postural dizziness
• Periorbital purpura(‘ racoon eye’ appearance)
• Macroglossia

Cardiorespiratory

• Dyspnoea
• Palpitations
• Chest pain
• Fatigue

Urinary

• Frothy urine
• Reduced urine output
• Nocturia

General

• Easy bruising / bleeding
• Intertriginous purpura
Vague pervasive symptoms These may include unintentional weight loss, fatigue, presyncope, postural hypotension, gastrointestinal disturbance, peripheral neuropathy including autonomic nervous dysfunction, erectile dysfunction and limb oedema.
Investigation
A few simple tests may confirm suspicions of amyloidosis. That said, the diagnosis is complex and diagnostic confirmation requires involvement of a specialised service. If amyloidosis is suspected, prompt referral is warranted.
Box 1 outlines clinical scenarios that
Box 1. When to refer on suspicion of amyloidosis
Proteinuria
• Order a monoclonal gammopathy screen( serum and urine protein electrophoresis and serum free light chains) to assess for a monoclonal band, indicative of a plasma dyscrasia causing AL amyloidosis. Refer urgently to a haematologist or nephrologist.
Heart failure
• Cardiologist investigation and management is warranted.
• Heart failure with preserved ejection fraction makes amyloidosis cardiomyopathy more likely.
• Cardiac B-type natriuretic peptide may indicate amyloidosis cardiomyopathy before heart failure is symptomatic. 8
• A bone scan( cardiac amyloid bone scintigraphy) in ATTR amyloidosis can be diagnostic and avoids the need for risky and invasive cardiac muscle biopsy.
Online resources
• Australian Amyloidosis Network aan. org. au( Includes amyloidosis treatment centres of excellence)
• Leukaemia Foundation bit. ly / 3zTFL21
• Optimal care pathway for people with AL amyloidosis, June 2023 bit. ly / 3TDidF5
was PBS-listed in 2024 for the treatment of ATTR amyloidosis cardiomyopathy. This agent may delay disease progression. Sim-
Figure 1: The many potential manifestations of AL amyloidosis.
warrant further investigation and immediate specialist referral on suspicion of amyloidosis. This may be to a haematologist, nephrologist, cardiologist, neurologist, gastroenterologist or dermatologist, depend-
Gastrointestinal manifestations
• Gastroenterology review for endoscopy or colonoscopy is indicated
• Biopsies need to be stained with Congo red for amyloid. This may be performed retrospectively on retrieved samples, if these are still available.
ilarly, patisiran, a double-stranded small interfering RNA that blocks TTR mRNA, was PBS-listed in 2024 for treatment of ATTRv with neuropathy.
There are ongoing trials of multiple
ing on presenting organ involvement.
promising new therapies both in Australia
Definitive diagnosis may be complex.
and internationally.
Biopsy samples, stained with Congo red for amyloid( staining apple-green birefringence under polarised light) may aid iden-
Australian Amyloidosis Network outlines where to locate these centres of excellence nationally( see online resources).
treatment of the underlying infectious or inflammatory disorder, where applicable.
A number of novel disease-modify-
Conclusion
Amyloidosis is a rare condition which
tification of the condition. However, biopsy of potentially affected organs, including liver, kidney and heart, carry signifi-
Treatment
The treatment of amyloidosis is highly
ing agents targeted at amyloidosis have been developed in recent years, which has resulted in significant improvements
can present with myriad manifestations. Early identification and specialised targeted treatment is critical for improv-
cant rates of complications. Additionally,
specialised and can be very effective when
in disease survival and quality of life for
ing morbidity and mortality outcomes
even when amyloid is identified histolog-
the condition is diagnosed early. Treat-
these subtypes of amyloidosis.
for patients with this condition. GPs have
ically, this does not determine whether
ment varies widely based on the type of
These agents include daratumumab
an important role to play in suspecting
the finding is localised( often not serious)
amyloidosis, and whether there is a dis-
( an anti-CD38 monoclonal antibody) in
amyloidosis, particularly in those with
or systemic( can range from incidental to
ease process that may be directly targeted,
combination with bortezomib( a protea-
suggestive presentations, when more
rapidly fatal). Specialised amyloidosis cen-
to reduce amyloid deposits. For example,
some inhibitor). This combination was
typical diagnoses have been excluded.
tres of excellence can confirm the type of amyloidosis with immunohistochemistry, immunofluorescence or proteomics. The
in AL amyloidosis, this involves measures to suppress the underlying plasma cell dyscrasia, and in AA amyloidosis,
PBS-listed in January 2023 for the initial treatment of AL amyloidosis.
Tafamidis, a selective stabiliser of TTR
References on request from kate. kelso @ adg. com. au