(2,3) Psoriatic & Reactive Arthritis

Question 1

5-7% of patients with ____ develop psoriatic arthritis

Answer 1

psoriasis
(must have this Dx first)

Question 2

A patient with more surfaces of rough skin and bad dandruff is at most risk of developing ____

Answer 2

joint symptoms (psoriatic arthritis)
(more severe psoriasis = ^risk)

Question 3

Where is psoriasis usually located?

Answer 3

• extensor surfaces around elbows
• knees
• back
• scalp (dandruff)
• pubic regions

Question 4

In a patient with psoriatic arthritis, ____ symptoms precede ____ symptoms

Answer 4

skin; joint

Question 5

At what age do joint symptoms tend to manifest in patients with psoriatic arthritis?

Answer 5

20-50yrs

Question 6

What joints are commonly affected by psoriatic arthritis?

Answer 6

(prefers UE)
- hands (DIPs)
- foot
- SI
- T/L
- c/s

Question 7

The earliest manifestation of psoriatic arthritis is in what joints?

Answer 7

DIP (hands)

Question 8

What gene is implicated in psoriatic arthritis?

Answer 8

HLA-B27

Question 9

What are the clinical manifestations of psoriatic arthritis?

Answer 9

• psoriatic skin rash, bleed when scratched
• dactylitis (spindle digits & sausage digits)
• asymmetrical stiffness & pain (after inactivity)
• pitting (deep grooves) of nails
• arthritis mutilans (later stage)

Question 10

Describe the appearance of a psoriatic skin rash

Answer 10

sharply demarcated, non-elevated, erythematous skin lesions covered by dry silvery lesions

Question 11

Swelling around the joints of the fingers is called ____

Answer 11

spindle digits

Question 12

Swelling of the entire length of the digits is called ____

Answer 12

cocktail sausage digits

Question 13

In psoriatic arthritis, dactylitis initially presents as ____, and may progress to ____

Answer 13

spindle digits
sausage digits

Question 14

What are the common radiographic characteristics of psoriatic and reactive arthritis in the spine and SI joints?

Answer 14

• uniform narrowing of jt space
• asymmetrical sacroiliitis (bilat. or unilat.)
• para/non-marginal syndesmophytes

Question 15

What are the radiographic characteristics specific to psoriatic arthritis in the extremities?

Answer 15

• marginal erosions & fluffy periostitis –> deformities (mouse ear, pencil-in-cup/mortar-in-pestle)
• spindle digits, cocktail digits
• Ray pattern
• Arthritis mutilans (opera glass hand / main en lorgnette)
• hitchhiker thumb, swan neck, boutonniere deformities

Question 16

What is pencil-in-cup deformity?

Answer 16

peripheral erosion of proximal bone + central erosions of distal bone
(*don’t confuse w/ Gull-wing)

Question 17

What joint’s in the hand commonly have mouse ear deformity in patients with psoriatic arthritis?

Answer 17

DIP

Question 18

What is another name for reactive arthritis that should ABSOLUTELY NEVER be used?

Answer 18

Reiter’s syndrome
(bad dude)

Question 19

What demographic is primarily affected by reactive arthritis?

Answer 19

• almost exclusively men (men are sluts; 50:1)
• onset in 18-40s

Question 20

What is the classic triad of symptoms seen in reactive arthritis?

Answer 20

“can’t see, can’t pee, can’t dance with me”
- conjunctivitis
- urethritis
- polyarthritis (SI jts & LE)

Question 21

What are the most common STIs that precede reactive arthritis?

Answer 21

1. chlamydia
2. gonorrhea
   (can affect HIV pts)

Question 22

What enteric disease may precede reactive arthritis?

Answer 22

• Shigella
• Yersinia enterocolitica
• salmonella

Question 23

What genetic variant is commonly associated with reactive arthritis?

Answer 23

HLA-B27

Question 24

What is generally the earliest symptom of reactive arthritis?

Answer 24

urethritis (burning & ^frequency)

Question 25

What are the clinical features of reactive arthritis?

Answer 25

- urethritis - conjunctivitis - asymmetrical polyarthritis - keratoderma blennorrhagica - Balanitis circinata (penile lesion)

Question 26

What is keratoderma blennorrhagica?

Answer 26

red bumps or pustules on the palms, soles of the feet, and trunk, resembling psoriasis or meningitis, but caused by reactive arthritis

Question 27

What are the radiographic characteristics specific to reactive arthritis?

Answer 27

- Favors LE - Lover's heel

Question 28

What is Lover's heel?

Answer 28

- inflammatory erosion from the retrocalcaneal bursa adjacent to the achilles tendon insertion - inflammatory enthesophytes at plantar fascia origin

Question 29

What are the target sites of reactive arthritis?

Answer 29

- SI jts (unilateral or BL asymmetric) - spine - calcaneus (lover's heel) - ankle - knee - forefoor - shoulder - wrist

Question 30

What are the relevant laboratory findings of reactive arthritis?

Answer 30

- HLA-B27 positive - RF negative - anemia, leukocytosis - ^ESR/CRP - often no organism isolated at culture of urethral specimen (occurs 6mo - 2yrs post STI)