Rheumatology Flashcards
Which 2 ANA subtypes are specific for a diagnosis of SLE?
The anti-DSDNA and anti-Smith antibodies are specific to lupus.
Anti-U1-RNP is a very sensitive indicator for which rheumatologic disorder?
Anti-U1-RNP is a sensitive but not very specific indicator of mixed connective tissues disease.
Which rheumatologic disease is associated with a positive c-ANCA and anti-PR3?
Granulomatosis with polyangiitis is associated with c-ANCA and anti-PR3.
Name 2 diseases that are p-ANCA+ and anti-MPO+.
Microscopic polyangiitis, eosinophilic granulomatosis with polyangiitis are associated with c-ANCA and anti-MPO+. Other diseases that are positive for these antibodies include pauci-immune RPGN, anti-GBM disease, and drug induced (PTU, methimazole, levamisol).
Name 2 diseases that consume complement during a flare
Hypocomplementemia is seen in SLE, vasculitis, RA, and infectious endocarditis.
Other than rheumatoid arthritis, a positive RF can be seen with which other diseases?
Other than RA, a positive RF can be seen in chronic infections (TB, HIV, viral hepatitis), chronic lung disease, Sjogren’s, SLE, infectious endocarditis, and hematologic malignancy.
What antibody test is more specific than RF for rheumatoid arthritis?
Anti-CCP (anticitrullinated cyclic peptide) is more specific for RA than the RF.
Compare and contrast “noninflammatory”, “inflammatory”, and “septic” joint fluid.
“Noninflammatory” joint fluid has <2000 WBC with clear to light yellow color and normal viscosity. “Inflammatory” joint fluid has 2,000-100,000 WBC with light yellow to cloudy color and low viscosity. “Septic” fluid has 15,000 and higher WBC with yellow to green color.
Describe gout crystals and their birefringence.
Uric acid crystals are needle shaped and exhibit negative birefringence (yellow) under polarized microscopy.
Describe calcium pyrophosphate (pseudogout) crystals and their birefringence.
Calcium pyrophosphate crystals are rhomboid-shaped and positively birefringent (blue) under polarized microscopy.
How long is the typical morning stiffness in RA vs. OA?
Morning stiffness last >1 hour in RA and less than 30 minutes in OA.
What are the essential diagnostic criteria for RA?
The diagnostic criteria for RA include: inflammatory arthritis (1 to 10 joints), positive RF and/or anti-CCP, increased ESR/CRP, and duration >6 weeks.
What imaging tests are mandatory before electively intubating a patient with RA?
Before electively intubating a patient with RA, flexion and extension cervical spine Xrays should be performed to rule out atlanto-axial instability.
What part of the spine is sometimes involved in RA? Which parts are not involved?
RA involves the cervical spine but does not involve the thoracic or lumbar spines or the SI joints.
Name the pulmonary manifestations of RA.
Pulmonary manifestations of RA include exudative pleural effusion, diffuse interstitial fibrosis, and intrapulmonary nodules.
What is Felty syndrome?
Felty syndrome is the triad of RA, splenomegaly, and neutropenia
Which DMARD is recommended by the American College of Rheumatology as 1st line for all moderate-to-severe cases of RA?
The ACR considers methotrexate to be the 1st line DMARD treatment for RA.
What follow up is required in patients treated with hydroxychloroquine?
The most common adverse effect of hydroxychloroquine is retinopathy. Therefore, baseline ophthalmology exam and annual exams once patient has been on MTX for 5 years are indicated.
What are the categories of biologics used to treat RA?
The categories of biologics used to treat RA include: anti-TNF alpha, CTLA-4/costimulator inhibitor, IL-6 inhibitor, IL-1 antagonist, and monoclonal Ab to CD20.
What are the representative drugs for each category of biologics?
TNF-alpha inhibitors: Infliximab, Adalimumab, Golimumab, Certolizumab
TNF-alpha inhibitor (small molecule): Etanercept
CTLA-4/costimulator inhibitor: Abatacept
Monoclonal AB to CD20: Rituximab
IL-1 antagonist: Anakinra
Name some serious complications of the various biologics.
All biologics are associated with increased risk of infection. The monoclonal AB TNF-alpha inhibitors are associated with lymphoma and skin cancers, reactivation of TB, heart failure.
Which DMARDs are relatively safe during pregnancy?
Hydroxychloroquine and sulfasalazine are safe in pregnancy. TNF-inhibitors are generally safe in pregnancy, but consider stopping at 30 weeks gestation to decrease risk of infection and placental transfer of drug.
Characterize the pattern of arthritis in SLE.
The arthritis of SLE is inflammatory and nonerosive. It can be symmetrical or asymmetrical, oligoarticular or polyarticular, and can affect large or small joints.
What are the patterns of skin rashes in SLE?
Chronic cutaneous lupus erythematosis (aka discoid lupus) is localized with central scarring/atrophy. It portends a more benign course of lupus. Acute cutaneous lupus erythematosis (ie. malar rash) flares with disease activity. Subacute cutaneous lupus erythematosis is an annular rash seen in SLE, Sjogrens and with certain medications including calcium channel blockers.