Review Question - QID 109136

Action	Numeric Key	Letter Key	Function Key
Choose 1	1
Choose 2	2
Choose 3	3
Choose 4	4
Choose 5	5
Submit Response			Enter
Previous Question			Left Arrow
Next Question		N	Right Arrow
Open/Close Bookmode		C
Open Image			Spacebar

Hypersensitivity Reactions QID: 109136 (M2.DM.17.4769)

QID 109136 (Type "109136" in App Search)

A five-year-old boy presents with his mother to your clinic complaining of a fever and rash. His mother says the patient was in his usual state of health until two weeks ago when he developed “strep throat.” He was prescribed a ten day treatment with oral amoxicillin by his primary care physician, which he has since completed. The mother reports that he seemed to feel better until two days ago when he began to complain of joint pain and an itchy rash. His mother notes the patient is on an “alternative vaccine schedule.” She is nervous because her son attends day-care three days a week, and there has been a recent “viral" outbreak. The patient’s temperature is 103°F (39.4°C), blood pressure is 99/59 mmHg, pulse is 110/min, and respirations are 20/min with an oxygen saturation of 99% O2 on room air. On physical exam, you note cervical adenopathy, joint swelling, mild peripheral edema, and a diffuse rash (shown in Figure A). Which of the following is the best treatment for this patient’s condition?

Type & Select Correct Answer

Type in at least one full word to see suggestions list

Penicillin

3/39

Aspirin and IVIG

18%

7/39

Rituximab

10%

4/39

Diphenhydramine

56%

22/39

Vitamin A

3/39

Select Answer to see Preferred Response

Review TC In New Tab

This patient is presenting with fever, joint pain, and an urticarial rash following administration of amoxicillin, suggesting the diagnosis of serum sickness-like reaction, which is managed by removal of the offending agent and symptomatic treatment with an anti-histamine (diphenhydramine).

Serum sickness and serum sickness-like reactions are type III hypersensitivity reactions that classically occur 5-10 days following exposure to rituximab, infliximab, beta-lactams, sulfa drugs, and anti-venoms. Symptoms include fever, arthralgia, lymphadenopathy, an urticarial rash, and possible renal involvement. It is often a self-limited reaction. Management involves removal of the offending agent and symptomatic treatments such as anti-histamines or steroids.

Figure A is a photograph of the skin showing urticaria, described as smooth, slightly elevated plaques (wheals) that are erythematous.

Incorrect Answers:
Answer 1: Penicillin is the treatment for acute rheumatic fever, which can develop after untreated pharyngeal streptococcal infection, presenting with fever, joint pain, and skin nodules/erythema marginatum. However, this patient did receive proper treatment. Moreover, penicillin would be contraindicated in serum sickness-like reactions caused by exposure to a beta-lactam.

Answer 2: Aspirin and immediate IVIG would be indicated in Kawasaki disease. Although Kawasaki disease can present with fever and adenopathy, there would also likely be evidence of conjunctivitis, a strawberry tongue, and desquamation of the hands and feet. Additionally, the rash associated with Kawasaki disease is normally a polymorphous, truncal rash - not urticaria.

Answer 3: Rituximab can be used to treat systemic juvenile idiopathic arthritis (Still’s disease). This presents as daily spiking fevers, polyarthritis, and an evanescent, salmon-colored rash.

Answer 5: Vitamin A can be used in the management of measles to reduce mortality. Measles presents with an erythematous, maculopapular rash. Measles, specifically, may also present with cough, coryza, conjunctivitis, and Koplik’s spots.

Bullet Summary:
Serum sickness and serum sickness-like reactions should be managed by removal of the offending agent (e.g., beta lactams and sulfa drugs) and with symptomatic treatment.

Rating

Please Rate Question Quality

4.8

(4)