Day 1 question 180-190

Day 1
question 180-190
http://usmlestep3blog.com/usmle-step-3-mcq/question-of-the-week-190/

erythema nodosum

Erythema nodosum (EN) is an acute, nodular, erythematous eruption that usually is limited to the extensor aspects of the lower legs. 

Erythema nodosum can be self-limited and resolve on its own in three to six weeks. After it's gone, it may leave only a temporary bruised appearance or a chronic indentation in the skin where the fatty layer has been injured.

What causes erythema nodosum?

the most common cause of erythema nodosum is streptococcal infection in children and streptococcal infection and sarcoidosis in adults.

Erythema nodosum may occur as an isolated condition or in association with other conditions. Conditions that are associated with erythema nodosum include medications (sulfa-related drugs, birth control pills, estrogens), strep throat, Cat scratch disease, fungal diseases, infectious mononucleosis, sarcoidosis, Behcet's disease, inflammatory bowel diseases (Crohn's disease and ulcerative colitis), and normal pregnancy.

Erythema nodosum and Pyoderma Gangrenosum indicate poor prognosis in ulcerative colitis. Other poor prognostic features in UC are lymphopenia, pancolitis and hypoalbuminemia.
Proctitis indicate left sided involvement only , better than pancolitis. ANCA has no prognostic value

Lichen Sclerosus

Lichen sclerosus is a chronic skin disorder that most commonly affects post-menopausal women. 

Menopause + vulva itching = suspect lichen sclerosus until proven otherwise .

vulva biopsy

Hair-on-end skull: Thin fine linear extensions radiating out from the skull that look on an X-ray like hair standing "on-end" from the skull, an appearance associated with hemolytic anemias such as sickle cell diseaseand thalassemia.

The "hair" represents the accentuated trabeculae extending between the inner and outer skull tables through the diploe in the expanded bone marrow space (because the bone marrow has expanded due to the excessive breakdown of red blood cells). The "hair" appears to be "on end" because the trabeculae are oriented perpendicular to the inner and outer tables of the skull.

amyloidosis

the condition is related to abnormal and excess production of antibodies by a type of immune cell called plasma cells. Clumbs of abnormal proteins build up in certain organs. This reduces their ability to work correctly.

This disease can affect the tongue, intestines, skeletal and smooth muscles, nerves, skin, ligaments, heart, liver, spleen, and kidneys.

Symptoms include:

• Abnormal heart rhythm
• Swollen tongue
• Fatigue
• Numbness of hands or feet
• Shortness of breath
• Skin changes
• Swallowing problems
• Swelling in the arms and legs
• Weak hand grip
• Weight loss

The first step in diagnosing amyloidosis should be blood and urine tests to look for abnormal proteins.

Tests that can help confirm the diagnosis include:

• Abdominal fat pad aspiration
• Bone marrow biopsy
• Rectal mucosa biopsy

This condition is treated the same way as multiple myeloma.

Treatment may include:

• Chemotherapy 
• Stem cell transplant

Thalassemia
http://www.marchofdimes.com/baby/birthdefects_thalassemia.html

MS flare
IV corticosteroid
if contraindicate, use plasma exchange
if frequent relapse, disease modify agent, such as interferon beta,

First step is to evaluate and stop the offending agent always! ETOH abuse can lead to hypertriglyceridemia and stopping ETOH can bring back TGs to normal.
If patient persistently has hypertriglyceridemia even after ETOH cessation, then fibrates or niacin or statin are appropriate depending on whether TG alone is elevated ( TG alone – fibrates are first choice) or if there are concomitant HDL/ LDL abnormalities.

Which anti-lipid therapy to choose. Here is a general guideline on treating lipid abnormalities – combinations :

LDL high – Statin
LDL high + HDL low – statin
TG moderately high + LDL high – Statin
TG moderately high + HDL low – Niacin
TG very high – Fibrates
TG very high + HDL low – Fibrates
TG very high + LDL high – Statin + Fibrates

What is needed for your exam?

Remember when LDL is high, STATIN always gets first preference and statin can also modestly increase HDL level. If you do not achieve the LDL or HDL goals, you can always combine other agents.

If low HDL is the only risk factor; NIACIN gets the preference ( It can increase HDL by 35% max – no other drug can increase more than 20%). Side effects of Niacin are severe flushing and headaches. Start low dose and slowly tit-rate up based on tolerance.
If severe elevation in TGs are the only problem, fibrates get preference. No other drug can reduce TGs as much as fibrates do. ( Niacin reduces by 25, Statins by 15% % where as fibrates reduce TG by 40%)

Lipid lowering class of Fibrates: Gemfibrozil, Clofibrate, Fenofibrate

Gemfibrozil belong to the same class “fibrates” and can be used in pure hypertriglyceridemia and it is a cheaper alternative to other fibrates ( Clofibrate and fenofibrate). If a patient has acute pancreatitis from hypertriglyceridemia, pharmacological intervention is needed to prevent future attacks and in such cases fibrates can be used . All Fibrates have an additional advantage of increasing HDL cholesterol. Gemfibrozil can cause rhabdomyolysis especially, when combined with statins ( this toxic effect is lesser with other fibrates)
So, when a patient has high TG and low HDL –> any fibrtae is a preferred choice but if they are also on statins, would use other fibrates rather than gemfibrozil because it has higher incidence of rhabdomyolysis.