Rheumatology multiple choice question bank

Ask the 3 key questions in your history:

Do you have any pain or stiffness in your arms, legs or back?

Can you walk up and down stairs without any difficulty?

Can you dress yourself without any difficulty?

Now if you can remember these three then you’re onto a winner. The GALS screening questions were designed to be used across medical schools in the UK and has the support of
a) The British Society of Rheumatology
b) THe ARC (Arthritis Research Council)

Remember GALS is different to REMS

REMS is Regional Examination of the Musculoskeletal System or put more simply examining the upper limbs / lower limbs / spine. This is in turn different to the examination of “the hands” or “the hip” etc.

ACR Criteria: 4 from 7 for at least 6 weeks

Morning Stiffness for > 1 hour
3 or more joint arthritis PIP/ MCP Wrist elbow ankle and MTP (i.e. not the hip neck back or shoulder).
Arthritis of wrist MCP or PIP joint
SymetricalRheumatoid nodules over extensor surfaces
Radiographic chances including erosions or periarticular osteopaenia
Positive Rheumatoid Factor

Therefore:
MRI scans and ultrasound are not used
Anti CCP antibody is not used
Biopsy / joint aspiration is not used.

CCP (Cyclic citrullinated) antibodies and MRI scans appear to be highly sensitive and specific for rheumatoid arthritis, however they do not form part of any formal ACR criteria.

Young man.
“Hip” pain.
Sclerotic SI joints?
This is ankylosing spondylitis: the classical Xray changes are:

Bridging syndesmophytes that actually represent ossification of the annulus fibrosus: the hardd ring of fibrous tissue that surrounds the intervertebral disc. Its these syndesmophytes that fuse together resulting in the fused spine of ankylosing spondylitis.
Squaring of the anterior bodies of the vertebrae.
Sclerotic Corners of the vertebrae.
Sacroiliitis: sclerosis of the sacroiliac joints as a result of inflammatory arthritis.

Benign Joint Hypermobility Syndrome

The Beighton score is used to define if someone is hypermobile and is scored as follows:

Hands flat on the floor with knees straight: 1 point
Elbows 10 degrees past midline: 1 point
Knees 10 degrees past midline: 1 point each
Little finger 90 degrees past midline: 1 point each
Thumbs against wrist: 1 point for each

Beighton Criteria: 4 or more out of 9 plus symptoms.

So from what we’re given here this patient has a beighton score of at least 5/9 and joint sympotms for >3/12. The “best” answer is therefore hypermobility.

REMEMBER c.10% of the normal population have a positive rheumatoid factor.

Diabetes Mellitus

The xray changes strongly suggest a Charcot joint: a joint damaged by lack of sensation / proprioception leading to overloading and subsequent catestrophic destruction.

The changes include what’s known as the 5D’s of a Charcot joint:

Destruction of the joint
Disorganisation (bones not arranged in the correct /usual arrangement through gross destruction e.g. cuniforms of the foot.
Increased density (sclerosis)
Debris (boney debris from a destoryed joint: often with well defined margins
Dislocation

Proximal muscle weakness

Fibromyalgia is a disorder characterised by soft tissue pain / sleep disturbance and unrefreshing sleep.

Its commonly associated with low mood.
Up to 25% of patients with SLE have fibromyalgia.

Clinical signs consist of multiple soft tissue tender points which essentially cause “non articular ” pain.

Weakness / high inflammatory markers/ abnormal clinical examination other than pain suggests the need to look for another underlying disorder. Its often a diagnosis of exclusion, and the differential diagnosis is wide.

Symmetrical

Gout is not classically a symmetrical disease. It characteristically picks off the MTP’s and knees. Its associated with a high serum urate.

X-ray’s show erosive disease and peri-articular osteopaenia.

Symmetrical arthritis: think rheumatoid as the classical prototype.

Gout

The classical signs of gout on an Xray are:

Erosions with sclerotic margins
A relatively preserved joint space
Minimal periarticular osteoporosis
Nodules (these are in fact tophi)

So in this case: think gout.

He has a septic arthritis casued by a gram positive cocci infection

A knee aspirate is the investigation of choice in most patients with an acute mono arthritis. In this case you would have to consider an underlying reason for the infection e.g.
Immunosupression (drugs/HIV)
Immunoglobulin deficiency
Other bacterial source for infection (e.g. abscess in intra venous drug user)

It is unusual for a 27 year old man with a swollen joint to have a gout…

The slide is a gram positive cocci – gram positive organisms stain purple.

Osteoarthritis

There are classically 4 signs of OA on an Xray:

Subchondral bone sclerosis
Cystic Change
Osteophytes
Reduced Joint Space

Remember Osetophytes are characteristic of OA. In the hands this classically affects the thumb CMC joints.

There are classically 4 signs of OA on an X-ray:

Subchondral bone sclerosis
Cystic Change
Osteophytes
Reduced Joint Space

BUT! this is occurring in one joint in a distribution that is not classical of simple OA. (e.g. hands/ hip/ knee).

This is likely to be secondary OA from an older injury to that ankle. Other prior problems there (fracture/ avascular necrosis/ gout) can lead to joint damage and a secondary osteoarthritis.

Osteomalacia

She has a low serum calcium and a high alkaline phostphatase. These are the classic findings of osteomalacia in comparison to
osteoporosis (normal bone biochemistry).

The aetilogy is most likely vitamin D deficiency. But vitamin D deficiency isn’t right because there is a ‘better’ answer in osteomalacia: proximal weakness and bone pain / high alkaline phosphatase / vitamin D deficiency.

Psoriatic Arthritis

There are generally 5 types of psoriatic arthritis described.

They are:

1. symetrical
2. asymetrical
3. arthritis mutilans
4. spinal disease
   5 .DIP predominance

The X-ray Changes are similar to rheumatoid but they differ in their distribution, and the formaiton of pencil in cup deformities along twith osteolysis.

Asymmetrical distribution of disease
Often affects PIP and DIP joints
Relative absence of peri-articular osteoporosis
Erosions seen at the distal interphalangeal joints joints
Reduced joint space
Pencil in cup deformity (arthritis mutilans with telescoping of the fingers)- this is a result of osteolysis
Loss of the terminal tufts of the phalanges (acro-osteolysis)
Sacroiliac and spondylitic changes (similar to those of Ank. Spond.)

Symetrical disease?
Erosions?
This is classical of RA.

The classical signs of gout on an Xray are:

Erosions
Reduced joint space
Periarticular osteoporosis
Nodules

Characteristic Xray changes include erosions

Erosive disease is seen in inflammatory arthritis, most commonly A/ gout and Psoriatic arthritis.

To cover the other points:

RF positivity is not necessary for a diagnosis of RA. Such cases are called seronegative.
RA is around 3 times commoner in women than men.
Subchondral bone sclerosis is a characteristic feature of RA: this is along with Subchondral sclerosis/ joint space narrowing (also seen in RA) and bone cysts.
NSAIDs improve symptoms but do not modify the disease process.
Seropositive means “rheumatoid factor” positive or RF+. RA is only seropositive in a proportion of people. Conversely around 10% of the population will be RF positive.

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Specificity is therefore 99000 / (99300)

= 99/99.3

99 as a fraction of 99.3 is almost 1. The exact value is therefore 0.9969

[ or 99.69% specific ]

Therefore the answer is >99% specific

False.

The GALS screening questions aim to identify if a patient has any global problem with their musculoskeletal system. It is intended as a screening test only.

Xray changes only form part of thediagnostic criteria. As ever the history is the most important tool for making the diagnosis.