34) A 10 y/o boy is brought by his mother for extensive rash on his lower extremities that started one day ago and has been worsening. There is no history of fever . The family just returned four days ago from a camping trip and the mother does not recall any exposure to ticks except that the boy stepped in to a bush while walking downhill. On examination, there is extensive erythema along with vesicles and bullae on the front and the back of bilateral lower extremities up until the level of the knees. The upper portion of the lower extremities is unaffected. The rest of the physical examination is normal. The best treatment for the management of this child’s condition is : •
A. Topical triamcinolone •
B. Prednisone orally •
C. Ceftriaxone intra-muscular •
D. Diphenhydramine •
E. Observation
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Archer USMLE Step 3 Blog 
b
B. Prednisone orally ….. Poison Ivy
b
b
A
Can you please comment on this question, Dr. Archer?
A
A
Option B prednisone is recommended for more extensive involvement.
B
D_diphenhydramine- benadryl
B
If the rash is widespread or results in a large number of blisters, prescribe an oral corticosteroid, such as prednisone
Dr. Archer would you please comment on this question. Thanks
Prednisolone orally B.
The initial treatment is prevention, cleaning it with alchol and washing it with water but for sever cases you give oral predinisone.
B
b
AA -topical triamcilone
B
D. Can give topical steroid.
Dr Archer,
Could you kindly clarify why we do not give antihistamines and give sterfoids?
a
This is a case of Contact dermatitis and oral prednisolone is the answer because the patient has developed type 4 hypersensitivity reaction.
I too would like to know why a topical steroid is not appropriate. The child is growing, best to avoid orally administered steroids. Also, contact dermatitis is not without symptoms sich as itch and pain. Would not benedryl assist with those as well?
Topical steroids do not control migration of central T effector memory cells. Meaning, they do not affect migration and homing memory cells nor do they suppress these cells outside the inflamed area. Recruitment of these ‘rogue’ cells will delay recovery compared to systemic oral steroid. (which suppress these cells as well)
Another problem is that the application and absorption of topical agents is erratic causing an erratic response compared to systemic agents. Oral steroids provide relief in 12 -24 hours.
The issue of growth becomes a concern in long term steroid therapy like in childhood asthma. There are no studies that show that short term (like 1 week) systemic steroid therapy will delay growth or cause short stature. Short term Systemic steroid will provide the best response for pain, itch and swelling.
Evidence based medicine?, until somebody proves that use of systemic steroid for 1 week affects growth. The best treatment in terms of response profile would be systemic not topical steroids. Of course avoidance of trigger is the best preventive measure, but we are past that stage in this patient.
Until it is proven that short term steroid therapy is dangerous, there is no reason to avoid systemic steroids in acute contact dermatitis such as poison ivy. Short term oral steroid will provide the best treatment vs topical, observation. Diphenhydramine will be ineffective because this is not a histamine mediated reaction. Ceftriaxone has anti infective and anti-inflammatory properties (shown in the nervous system) in rat models but it has not be proven to be effective for this purpose in acute contact dermatitis like poison ivy.
References:
http://www.ncbi.nlm.nih.gov/pubmed/20027934 -topical vs oral
http://www.ncbi.nlm.nih.gov/pubmed/18835197 – memory cells
http://www.ncbi.nlm.nih.gov/pubmed/10878177 – child growth
http://www.ncbi.nlm.nih.gov/pubmed/22710775 – ceftriaxone
Why not topical steroid
http://emedicine.medscape.com/article/911711-treatment
The American Academy of Allergy, Asthma, and Immunology and the American College of Allergy, Asthma, and Immunology have established a practice parameter for the management of contact dermatitis.[11]
Once the correct diagnosis has been established, many patients improve with adequate hygiene and avoidance of the contactant. Further therapy depends on the degree of involvement, duration, and presence or absence of secondary infection.
In acute contact dermatitis, contaminated clothing must be removed and the contactant rinsed from the skin with large quantities of water. Mild-to-moderate acute allergic contact dermatitis responds to topical care with astringents in a wet compress, topical corticosteroids, and systemic antipruritics. Acute severe allergic contact dermatitis with marked edema and bullae should receive the same treatment but may also require the addition of systemic corticosteroids.
Acute irritant contact dermatitis from acids or alkalis should be treated with vigorous irrigation with water to remove the irritant and then should be treated as a thermal burn. Treatment of chronic contact dermatitis requires identification and removal of the contactant.
Chronic allergic contact dermatitis should be treated with mid-potency topical corticosteroids and general skin care with emollients. Chronic irritant dermatitis is extremely common. Irritant dermatitis of the hands secondary to soaps or volatile solutions are exceedingly common in adolescents and adults.
Patients should be educated about the cause of the dermatitis and instructed in methods of skin protection and care with emollients.
Investigators have found that most people could be immunized against poison ivy through prescription pills; however, this procedure can take months to achieve a reasonable degree of hyposensitization and must be continued over a long period. Immunization can cause uncomfortable side effects and should only be considered for individuals, such as firefighters, who must live or work in areas where they come into constant contact with poison ivy.
Sounds like contact derm 2to poison ivy. Answer is B, since the question clearly states its been getting worse and there are bullae now (indicating severity). As we know, both topical steroids and a/histamines are right choices in mild/moderate cases and since they both are indicated as potential answers, picking choice A or D wont be correct. Given the severity, PO prednisone of short course is the answer.
The question is ‘what is the best treatment?’
My answer is Option B, oral or systemic steroid. Why?
The best treatment will provide effective relief in the quickest possible time. Any treatment that falls short of this is not the best and option B stands out.
Some of my colleagues are concerned about side effect profile of oral or systemic steroid. Short term steroid use has not been shown to cause any problems in normal children and normal adults.
Moreover, the only drug in the list of options that will control the systemic interleukin surge in this patient is systemic steroids. He has a sizable effector T cell mediated flare and the best treatment should control this surge effectively. Even though I have not heard of systemic inflammatory response syndrome from poison ivy, interleukin surge is not beneficial in this case (this is a hypersensitivity reaction) and it will only delay recovery.
Observation – No, not justified. Patient has pain, itch, and symptoms ‘are worsening’ and ‘extensive’. You must do something to alleviate symptoms.
Diphenhydramine – No, it’s ineffective. This is not a histamine mediated reaction. Same way, Poison ivy can not cause anaphylaxis but it can theoritically cause SIRS or a systemic reaction.
Topical triamcinolone – Not as effective as Option B. It does not suppress central memory T cells and recruitment of these cells delays recovery. Option B suppresses these cells.
Ceftriaxone – is not approved for management of poison ivy reaction. It is not the best treatment for poison ivy reaction.
References:
http://www.ncbi.nlm.nih.gov/books/NBK27149/ – armed effector T cell
http://emedicine.medscape.com/article/168943-overview#a0104 – SIRS
http://en.wikipedia.org/wiki/Systemic_inflammatory_response_syndrome – SIRS
http://en.wikipedia.org/wiki/Cytokine_storm – Cytokine storm
http://www.aafp.org/afp/2010/0801/p249.html – Mgx of Contact Derm.
…and the official answer from Dr. Red is…?
Contact Dermititis
ID causative agent → remove
Rx mild case w/ antihistamines and topical steroids, or traimcinolone
IF > 10% of body or extensive bullae → oral prednisone 2-3w
A