A 17-year-old girl comes to the office for evaluation of a generalized rash. The rash was present when she woke up this morning and does not feel painful or itchy. For the past 10 days, the patient has had a sore throat, fever, fatigue, and body aches. She had a bottle of amoxicillin from a recent episode of pharyngitis and took a few pills this week, but the symptoms did not resolve. Her only medical problem was major depression, which resolved with behavioral therapy 3 years ago. She is sexually active and takes oral contraceptive pills. The patient takes no other medications. She does not use tobacco, alcohol, or illicit drugs. Temperature is 38 C (100.4 F), blood pressure is 110/76 mm Hg, pulse is 88/min, and respirations are 16/min. Physical examination demonstrates an awake but tired-appearing adolescent. There is no rhinorrhea, tympanic membranes are clear, and tonsils are enlarged and erythematous with white exudate bilaterally. There is tender cervical lymphadenopathy but no neck stiffness. S1 and S2 are normal. Lungs are clear to auscultation bilaterally. The abdomen is soft and nontender with mild hepatosplenomegaly. A diffuse, erythematous, blanching, maculopapular rash is seen on the chest, abdomen, and extremities. Laboratory results are as follows:

In addition to discontinuing antibiotics, which of the following is the most appropriate management for this patient's rash?

Question

A 17-year-old girl comes to the office for evaluation of a generalized rash. The rash was present when she woke up this morning and does not feel painful or itchy. For the past 10 days, the patient has had a sore throat, fever, fatigue, and body aches. She had a bottle of amoxicillin from a recent episode of pharyngitis and took a few pills this week, but the symptoms did not resolve. Her only medical problem was major depression, which resolved with behavioral therapy 3 years ago. She is sexually active and takes oral contraceptive pills. The patient takes no other medications. She does not use tobacco, alcohol, or illicit drugs. Temperature is 38 C (100.4 F) , blood pressure is 110/76 mm Hg, pulse is 88/min, and respirations are 16/min. Physical examination demonstrates an awake but tired-appearing adolescent. There is no rhinorrhea, tympanic membranes are clear, and tonsils are enlarged and erythematous with white exudate bilaterally. There is tender cervical lymphadenopathy but no neck stiffness. S1 and S2 are normal. Lungs are clear to auscultation bilaterally. The abdomen is soft and nontender with mild hepatosplenomegaly. A diffuse, erythematous, blanching, maculopapular rash is seen on the chest, abdomen, and extremities. Laboratory results are as follows:

In addition to discontinuing antibiotics, which of the following is the most appropriate management for this patient's rash?

Quizplus · Accepted Answer

Explanation: 11ec2b69_bfa4_c6c6_8f63_47016f72e1d6_MD0005_00 Infectious mononucleosis (IM) is a viral syndrome most commonly due to Epstein-Barr virus, with manifestations that commonly include fever, fatigue, exudative pharyngitis, lymphadenopathy, and hepatosplenomegaly. Liver function test results may be mildly elevated. Patients with IM may develop an erythematous exanthematous rash, which is usually maculopapular, urticarial, or morbilliform and most often erupts after inappropriate administration of amoxicillin or ampicillin. This etiology of this well-known phenomenon is unclear, although it may be an immune-mediated response to circulating antibodies against penicillin derivatives. The rash is not considered a true antibiotic allergy and will resolve spontaneously over time with observation and supportive care. (Choice A) Intravenous immunoglobulin is the appropriate treatment for Kawasaki disease, a vasculitis of unclear etiology that is characterized by fever, mucous membrane changes, cervical lymphadenopathy, conjunctivitis, extremity edema, and rash. Kawasaki disease is unlikely to be the source of this patient's rash as she does not meet these diagnostic criteria, is older than the typical age at onset, and has exudative pharyngitis. (Choice B) In IM, the rash will not improve if treated with medications used to combat allergic reactions (eg, corticosteroids, antihistamines). The rare occasions in which corticosteroids are indicated in the management of IM include severe sequelae such as hemolytic anemia or airway obstruction. (Choice D) Although a skin biopsy can be used to definitively diagnose an exanthem, it is not indicated when the diagnosis is clear (eg, rash following amoxicillin, which is well-documented in patients with IM). If the diagnosis is uncertain, or if symptoms fail to resolve in a timely manner, biopsy might be considered. (Choice E) Given the prolonged course of this patient's illness (10 days), it is unlikely that she has a bacterial infection requiring continued antibiotic therapy. Her clinical picture is classic for IM, a viral illness; therefore, no further antibiotic therapy is indicated. Educational objective: Amoxicillin administration in a patient with infectious mononucleosis classically causes a generalized maculopapular rash. The rash will resolve spontaneously after withdrawal of the antibiotic and observation alone. References: Incidence of rash after amoxicillin treatment in children with infectious mononucleosis. (http://www.ncbi.nlm.nih.gov/pubmed/23589810)

A 17-Year-Old Girl Comes to the Office for Evaluation of a Generalized