Epidemiology
Causes
Genetics/Path
Clinical Features
Treatment
100
age of peak incidence and geographic area of highest annual incidence?
age 20-39, northern europe (5-40/100,000
100
what bacteria commonly associated?
myobacterial and propionibacterial DNA and RNA recovered from sarcoid tissue. Serum of sarcoid patients often has ab to mycobacterial antigens.
100
Association with which hepatitis and sarcoid? and why?
Sarcoidosis has been reported to develop after IFN-a therapy for hep C; likely because IFN-a treatment increases IFN-g and IL_2 --> granuloma formation. Also, hep C infection itself may be involved.
100
What is the histological finding?
noncaseating epithelioid-cell granulomas w/o organisms or particles. basically, just a granuloma. you need to do AFB and fungi stains to make sure thats not the culprit
100
if you do need to treat sarcoid, what do you use?
steroids are the cornerstone. immunosuppressive and cytotoxic drugs are anecdotal, small sample sizes. hydroxychloroquine - sometimes for skin lesions, but no large studies. TNF-alpha inhibitors (thalidomide and pentoxifylline), no large studies
200
How much more common in black americans?
~3x; 35.5/100,000 vs 10.9/100,000. In black americans peak incidence occurs later in life in the fourth decade
200
Indications for chest CT for sarcoid patients?
unnecessary for most. indicated with CXR is atypical for sarcoid or if pt has hemoptysis.
200
Pathogenesis of pulmonary fibrosis in sarcoid?
Occurs in 20-25% of pts. Unopposed MMP 8 and 9. Shift from Th1 cell cytokines to Th2 cell cytokines-->activated macrophages --> fibronectin and CCL18--> upregulation of collagen production by lung fibroblasts --> increased CCL18 release --> loop
200
This is how you do the Kveim-Siltzbach test
injecting human sarcoid tissue extract intradermally, letting it percolate for 4 weeks, then biopsying the papule that develops. Most useful for people whose lesions are not easily accessible for biopsy.
200
This is the most common neuro manifestation of sarcoid:
CN palsies. then headache, ataxia, cognitive dysfunction. There are neuro manifestations in ~25% of patients
300
where does sarcoidosis get its name?
Norwegian dermatologist, named due to skin nodules with path resembling sarcoma (epithelioid cells with large pale nuclei and a few giant cells).
300
how do you treat erythema nodosum - sarcoid?
NSAIDs
300
What is Lofgren's syndrome?
Acute presentation of arthritis, erythema nodosum, bilateral hilar adenopathy (9-34% of pts). Women: erythema nodosum Men: marked ankle periarticular inflammation/arthritis w/o EN
300
This is how a diagnosis of sarcoidosis is confirmed.
CXR evidence + clinical features + noncaseating granulomas on biopsy with all other causes of granulomas ruled out
300
this is the most common optho manifestation
anterior uveitis (65% of optho involvement). optho involvement in 25-80% of patients.
400
Most common 3 organs involved?
lungs, eyes skin. This is why search for environmental causes centers on exposure to airborne antigens
400
does biopsy of erythema nodosum confirm the diagnosis?
no - occurs in 10% of pts, lasts ~3 weeks, biopsy shows nonspecific septal panniculitis
400
most common sarcoid presentation?
systemic symptoms (fatigue, night sweats, weight loss) + CXR with bilateral mediastinal lymphadenopathy.
400
This is how most patients with sarcoidosis are treated
most do not require therapy!! a good general rule is to start treatment when organ function is threatened.
400
this is a common enzyme abnormality seen in sarcoid
increased ACE - in 60% of patients. the granulomas make ACE
500
exposure to what type of environment + HLA-DQB1 locus has been identified as an interaction associated with sarcoid?
water damage, high-humidity in the workplace
500
Fundamental abnormality in sarcoid pathogenesis?
GRANULOMA development and accumulation due to CD4+ T cells + APC interactions (exact antigen unknown).
500
What is usual disease course? (what fraction have remission vs unrenting disease vs death from disease?)
1/2 - remission within a year 2/3 - remission within a decade 1/3 - unrelenting disease, clinical organ impairment <5% die (usually from pulm fibrosis with respiratory failure)
500
Can sarcoid patients get organ transplants?
yes - 1 and 5 year graft survival rates are no different than in patients without.
500
what is the pathophys of hypercalciuria/hypercalcemia/renal calculi in sarcoid?
sarcoidal macrophages have 25-hydroxyvitaminD-1a-hydroxylase to convert vit D to active form