Wild type ABeta2M amyloidosis

What it is

From: Orphanet

A form of amyloidosis affecting patients with chronic kidney disease (CKD), on long term dialysis characterized by the accumulation of amyloid fibrils consisting of beta 2 microglobulin (β2M) deposits in the musculoskeletal system leading to carpal tunnel syndrome (CTS), chronic arthropathy, cystic bone lesions, destructive osteoarthropathy, and pathologic fractures.

Reported clinical features and what the terms mean

The following findings are associated with this condition in Orphanet. They are not a checklist for diagnosing yourself, and they do not all occur in every affected person. Some are examination, imaging or laboratory findings that cannot be recognised at home.

The frequency labels describe how often a finding was reported among people with the condition in the source. They do not give the chance that a person with that symptom has the condition. Definitions below reproduce HPO terminology; they explain the term, not the likely severity in an individual.

Arthritis · Very frequent (99-80%)

Inflammation of a joint.

Neck pain · Very frequent (99-80%)

An unpleasant sensation characterized by physical discomfort (such as pricking, throbbing, or aching) localized to the neck.

Shoulder pain · Very frequent (99-80%)

An unpleasant sensation characterized by physical discomfort (such as pricking, throbbing, or aching) localized to the shoulder.

Abnormality of the thenar eminence · Frequent (79-30%)

An abnormality of the thenar eminence, i.e., of the muscle on the palm of the human hand just beneath the thumb.

Axonal loss · Frequent (79-30%)

A reduction in the number of axons in the peripheral nervous system.

Bone cyst · Frequent (79-30%)

A fluid filled cavity that develops with a bone.

Constrictive median neuropathy · Frequent (79-30%)

Injury to the median nerve caused by its entrapment at the wrist as it traverses through the carpal tunnel. Clinically, constrictive median neuropathy is characterized by pain, paresthesia, and weakness in the median nerve distribution of the hand.

Decreased amplitude of sensory action potentials · Frequent (79-30%)

A reduction in the amplitude of sensory nerve action potential. This feature is measured by nerve conduction studies.

Decreased nerve conduction velocity · Frequent (79-30%)

A reduction in the speed at which electrical signals propagate along the axon of a neuron.

Dysesthesia · Frequent (79-30%)

Painful sensations elicited by a nonpainful cutaneous stimulus such as a light touch or gentle stroking over affected areas of the body. Sometimes referred to as hyperpathia or hyperalgesia. Often perceived as an intense burning, dyesthesias may outlast the stimulus by several seconds.

Pain · Frequent (79-30%)

An unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage.

Paresthesia · Frequent (79-30%)

Abnormal sensations such as tingling, pricking, or numbness of the skin with no apparent physical cause.

Abnormal intervertebral disk morphology · Occasional (29-5%)

Any structural abnormality of the intervertebral disk.

Abnormal intestine morphology · Occasional (29-5%)

An abnormality of the intestine. The closely related term enteropathy is used to refer to any disease of the intestine.

Other findings in the same source

From: Orphanet

Additional reported features include Abnormality of the vertebral endplates (Occasional (29-5%)); Dysphagia (Occasional (29-5%)); Gastrointestinal hemorrhage (Occasional (29-5%)); Macroglossia (Occasional (29-5%)); Arthropathy (Occasional (29-5%)); Abnormal tendon morphology (Very rare (<4-1%)); Abnormality of the shoulder (Very rare (<4-1%)); Arrhythmia (Very rare (<4-1%)); Cardiac amyloidosis (Very rare (<4-1%)); Congestive heart failure (Very rare (<4-1%)). This is a selected summary, not a complete description of the condition.

When it may begin

From: Orphanet

Adult

Inheritance in the source

From: Orphanet

Not applicable

Frequency and the population described

From: Orphanet

Point prevalence: 1-9 / 100 000; Europe; Value and class.

Which doctor should you see?

The suggested department for discussing Wild type ABeta2M amyloidosis is Rheumatology, with a rheumatologist as the relevant type of clinician. General physician / Family Medicine; paediatrician for children. Referral depends on symptoms.

This is an editorial referral starting point. The appropriate clinic depends on the person’s age, symptoms, previous diagnosis and local services. The first clinician can decide whether another specialty or a team is needed; a department label does not confirm the diagnosis.

How to prepare for an assessment

Bring a short timeline of the main symptoms: when they first appeared, whether they are constant or episodic, what seems to change them, and how they affect daily activities. Include previous reports, discharge summaries, current medicines and supplements, allergies, and any relevant family history. A dated record is more useful than trying to match every feature in an online article.

Ask the clinician what is already established and what remains uncertain. If a test is suggested, ask what question it answers, what its limitations are and how the result would change the next step. The information here is not an instruction to arrange every possible test. In children, bring growth, developmental and school information if it is relevant to the concern.

• Are the findings inflammatory, structural or due to another mechanism?
• Is there evidence that other organs need assessment?
• How will function and any treatment-related risks be monitored?

Treatment discussions and follow-up

The material gathered for this draft does not provide a complete condition-specific treatment pathway for Wild type ABeta2M amyloidosis. That gap does not mean that treatment is unavailable. A clinician needs to establish the diagnosis and review current guidance before recommending medicines, procedures, rehabilitation or other support.

Before leaving the appointment, clarify the next review date, who will communicate results, and whom to contact if the situation changes. Discuss difficulties with sleep, work, school, mobility, eating or emotional wellbeing when these are relevant. Practical support may require coordination between the treating clinician and other services.

The collected references do not establish a complete prevention or long-term outlook section for this entry. Missing information should not be interpreted as proof that prevention is impossible or that a particular outcome is inevitable. Ask what is known for the exact subtype, stage and personal circumstances, and which uncertainties remain.

When to seek emergency help

Severe breathing difficulty, collapse, new stroke-like symptoms, a seizure that is prolonged or repeated without recovery, uncontrolled major bleeding, or an immediate risk of self-harm require emergency help. In India, call 112 or reach the nearest emergency department. This is a general, non-exhaustive warning list; it is not a condition-specific triage tool.