EN Question of the Day

[Guest guest]

Dear Group,

Here are some questions and answers with references by Dr. Gillam:

This week's QAD topic is: Erythema nodosum

* Question-A-Day for Monday, January 24, 2000 (1 of 7)

What is the underlying pathophysiology of erythema nodosum?

* Answer:

Erythema nodosum is an inflammatory eruption of the subcutaneous

fat.

* Reference:

p.1588-1589 Tintinalli, Kelen, Stapczynski: Emergency Medicine:

a comprehensive study guide 5th edition, McGraw Hill, c1999

* Thanks to:

Gillam, MD

Northwestern/ton Emergency Medicine Residency

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

* Question-A-Day for Tuesday, January 25, 2000 (2 of 7)

Where does erythema nodosum (EN) most commonly manifest itself

on the body?

* Answer:

EN is most commonly seen on the pretibial area of the lower

extremities, though the upper extremities and trunk can also be involved.

* Reference:

p.1588-1589 Tintinalli, Kelen, Stapczynski: Emergency Medicine:

a comprehensive study guide 5th edition, McGraw Hill, c1999

* Thanks to:

Gillam, MD

Northwestern/ton Emergency Medicine Residency

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

* Question-A-Day for Wednesday, January 26, 2000 (3 of 7)

How is erythema nodosum differentiated from cellulitis?

* Answer:

Individual lesions may be mistaken for bacterial cellulitis,

however, the nodular component supports the diagnosis of erythema nodosum.

* Reference:

p.1588-1589 Tintinalli, Kelen, Stapczynski: Emergency Medicine:

a comprehensive study guide 5th edition, McGraw Hill, c1999

* Thanks to:

Gillam, MD

Northwestern/ton Emergency Medicine Residency

+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

* Question-A-Day for Thursday, January 27, 2000 (4 of 7)

Do the nodular lesions in erythema nodosum ulcerate?

* Answer:

No. Ulceration is not a feature of EN, and should suggest the

possibility of another type of panniculitis.

* Reference:

p.1588-1589 Tintinalli, Kelen, Stapczynski: Emergency Medicine:

a comprehensive study guide 5th edition, McGraw Hill, c1999

* Thanks to:

Gillam, MD

Northwestern/ton Emergency Medicine Residency

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

* Question-A-Day for Friday, January 28, 2000 (5 of 7)

What are some of the causes of erythema nodosum (EN)?

* Answer:

There are numerous causes of EN including fungal organisms,

bacteria (Strep, Campylobacter, Yersinia, leprosy), parasites

(Toxplasmosis, Leishmaniasis), viruses (Herpes simplex, infectious

mononucleosis), medications (sulfa, contraceptive pills, penicillin,

bromides, vaccines), sarcoidosis, inflammatory bowel disease,

pregnancy, Behcet's syndrome, leukemia and lymphoma. Often cases are

idiopathic.

* Reference:

p.1588-1589 Tintinalli, Kelen, Stapczynski: Emergency Medicine:

a comprehensive study guide 5th edition, McGraw Hill, c1999

* Thanks to:

Gillam, MD

Northwestern/ton Emergency Medicine Residency

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

* Question-A-Day for Saturday, January 29, 2000 (6 of 7)

What studies should you consider obtaining after diagnosing a

patient with erythema nodosum?

* Answer:

Studies to consider might include a throat culture to rule out

strep, stool cultures to rule out campylobacter or yersinia, a CBC to

rule out leukemia, and chest x-ray to rule our sarcoidosis and a PPD.

* Reference:

p.1588-1589 Tintinalli, Kelen, Stapczynski: Emergency Medicine:

a comprehensive study guide 5th edition, McGraw Hill, c1999

* Thanks to:

Gillam, MD

Northwestern/ton Emergency Medicine Residency

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

* Question-A-Day for Sunday, January 30, 2000 (7 of 7)

What is the treatment of erythema nodosum?

* Answer:

Therapy focuses on the underlying cause. If no cause is found,

symptomatic relief with bed rest, leg elevation and NSAIDs can be

tried. Other treatments such as oral potassium iodide (SSKI) and

systemic steroids are typically instituted after the etiology is

established.

* Reference:

p.1588-1589 Tintinalli, Kelen, Stapczynski: Emergency Medicine:

a comprehensive study guide 5th edition, McGraw Hill, c1999

* Thanks to:

Gillam, MD

Northwestern/ton Emergency Medicine Residency