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Here is a NEJM review on Graves.
We also discussed anti-NMDA receptor encephalitis - there is a case presentation here. A discussion of paraneoplastic syndromes involving the CNS is posted here.
Infusion rate depends on volume status, heart function, etc, but should target 100-1500 cc urine output/hr - do not need to hydrate beyond euvolemia
If severe/symptomatic consider: Bisphosphonates (IV) - will not take effect for 48-72 hrs, but will help maintain normal calcium when achieved.
Calcitonin by nasal spray or subQ is also very effective.
If hyperCa2+ is from sarcoid or lymphoma consider steroids (20-40 mg/day) - this works by decreasing calcitriol production from activated mononuclear cells in the lung and lymph nodes.
AVOID LASIX since most patients are profoundly volume depleted initially and once replete can cause hypokalemia, hypomagnesemia, and lead to recurrence of volume depletion. A recent Annals of Internal Medicine article reviews the use/concerns regarding Lasix in hypercalcemia.
Dialysis should be consider if the above fail/can't be done because of renal failure or heart failure.
Sigmoid/Colonoscopy
Generally avoided with typical presentation and positive toxin EIA
Concern regarding endoscopy/insuflation of air causing perforation, especially if toxic megacolon present
May see pseudomembranes diagnostic of pseudomembranous colitis
Consider endoscopy if:
Cardiac Involvement - Myocarditis, pericarditis, arrhythmias
SEROLOGY - ANA+ in 80%. Ongoing research into myositis specific antibodies (currently felt to be present in 30%) to help determine likely clinical progression and treatment response
MALIGNANCY - Incidence of cancer is 5-7x higher than general pop'n. Peak incidence of diagnosis is within 2 years before or after the DM diagnosis. Search guided by complete history and physical. Bloodwork, imaging and tumor markers (CA125, CA 19-9, PSA) and age appropriate cancer screening.
Ongoing cancer surveillance suggested for 3-4 years after diagnosis or recurrence, with the exception of ovarian CA which can occur >5 years after diagnosis (therefore screen for longer).
Publications on malignancy frequency in DM/PM can be found here (don't forget they have a higher baseline incidence of nasopharyngeal CA in China - it isn't the most common DM associated cancer here) and here.
THERAPY- Treat the cancer!! (If you can find it without going overboard looking!)
Involves steroids at relatively high doese for prolonged periods of time. Steroid sparing agents such as azathipone and methotrexate are also used. Guided by clinical exam/weakness rather than CK/other markers.
As steroid course will be prolonged, be sure to consider the associated side effects and posible infections including TB.
Patients with polymyositis/dermatomyositis who have interstitial pulmonary fibrosis may be at increased risk for PCP with glucocorticoids alone compared to other populations.
A review of treatment can be found here.