Perinuclear antineutrophil cytoplasmic antibodies (pANCA) are most strongly associated with which condition?
Correct Answer B: cANCA = Wegener's; pANCA = Churg-Strauss + others.
ANCA:
There are two main types of anti-neutrophil cytoplasmic antibodies (ANCA) - cytoplasmic (cANCA) and perinuclear (pANCA).
For the exam, remember:
cANCA:
pANCA:
Other causes of positive ANCA (usually pANCA):
The presence of anti-cyclic citrullinated peptide antibody is suggestive of which one of the following conditions?
Correct Answer B: Anti-cyclic citrullinated peptide antibodies are associated with rheumatoid arthritis.
Anti-cyclic citrullinated peptide antibody may be detectable up to 10 years before the development of rheumatoid arthritis. It may therefore play a key role in the future of rheumatoid arthritis, allowing early detection of patients suitable for aggressive anti-TNF therapy. It has a sensitivity similar to rheumatoid factor (70-80%, see below) with a much higher specificity of 90-95%.
Rheumatoid factor:
Rheumatoid factor (RF) is a circulating antibody (usually IgM) which reacts with the Fc portion of the patients own IgG.
RF can be detected by either:
RF is positive in 70-80% of patients with rheumatoid arthritis, high titre levels are associated with severe progressive disease (but NOT a marker of disease activity).
Other conditions associated with a positive RF include:
A 27-year-old woman presents with painful genital ulceration. She has had recurrent attacks for the past four years. Oral acyclovir has had little effect on the duration of her symptoms. She has also noticed for the past year almost weekly attacks of mouth ulcers which again are slow to heal. Her only past medical history of note is being treated for thrombophlebitis two years ago.
What is the most likely diagnosis?
Correct Answer A:
Behcet's syndrome: Behcet's syndrome is a complex multisystem disorder associated with presumed autoimmune mediated inflammation of the arteries and veins. The precise aetiology has yet to be elucidated however. The classic triad of symptoms are oral ulcers, genital ulcers and anterior uveitis.
Epidemiology:
Features:
Diagnosis:
*More specifically HLA B51, a split antigen of HLA B5.
Which one of the following statements regarding the 2010 American College of Rheumatology / European League Against Rheumatism classification criteria for rheumatoid arthritis is correct?
Rheumatoid arthritis: diagnosis:
NICE have stated that clinical diagnosis is more important than criteria such as those defined by the American College of Rheumatology.
2010 American College of Rheumatology criteria Target population. Patients who:
Classification criteria for rheumatoid arthritis (add score of categories A-D; a score of 6/10 is needed definite rheumatoid arthritis) Key:
A 56-year-old lady is referred to rheumatology clinic due to severe Raynaud's phenomenon associated with arthralgia of the fingers. On examination you note shiny and tight skin of the fingers with a number of telangiectasia on the upper torso and face. She is also currently awaiting a gastroscopy to investigate heartburn.
Which one of the following antibodies is most specific for the underlying condition?
Correct Answer D: Limited (central) systemic sclerosis = anti-centromere antibodies.
This lady has some features of CREST syndrome. Although ANA is positive in 90% of patients with systemic sclerosis, anti-centromere antibodies are the most specific test for limited cutaneous systemic sclerosis.
Systemic sclerosis:
Systemic sclerosis is a condition of unknown aetiology characterized by hardened, sclerotic skin and other connective tissues. It is four times more common in females.
There are three patterns of disease:
1- Limited cutaneous systemic sclerosis:
2- Diffuse cutaneous systemic sclerosis:
3- Scleroderma (without internal organ involvement):
Antibodies: