A 29-year-old previously healthy man comes to the physician with malaise, rash, and joint pain with swelling for the last week. He has no energy and can hardly get out of bed. He has no abdominal pain, vomiting, or genital lesions. The patient reports several new sexual partners over the last year and says that he had a negative HIV test 2 months ago. He smokes marijuana but does not use tobacco, alcohol, or other illicit drugs.
His temperature is 38.2° C (100.7° F), blood pressure is 122/68 mm Hg, and pulse is 89/min. Several small, mobile lymph nodes are palpated in the submandibular region. There is no pharyngeal erythema. There is diffuse swelling, warmth, and pain with active motion in the elbow, knee, and ankle joints. The abdomen is soft and mildly tender in the epigastrium. There is no hepatosplenomegaly. Multiple urticarial skin lesions with excoriation are seen on the upper and lower extremities. There are no oral or genital lesions.
Laboratory results are as follows:

Which of the following would be most helpful in establishing a diagnosis in this patient?

Question

A 29-year-old previously healthy man comes to the physician with malaise, rash, and joint pain with swelling for the last week.  He has no energy and can hardly get out of bed.  He has no abdominal pain, vomiting, or genital lesions.  The patient reports several new sexual partners over the last year and says that he had a negative HIV test 2 months ago.  He smokes marijuana but does not use tobacco, alcohol, or other illicit drugs.
His temperature is 38.2° C (100.7° F), blood pressure is 122/68 mm Hg, and pulse is 89/min.  Several small, mobile lymph nodes are palpated in the submandibular region.  There is no pharyngeal erythema.  There is diffuse swelling, warmth, and pain with active motion in the elbow, knee, and ankle joints.  The abdomen is soft and mildly tender in the epigastrium.  There is no hepatosplenomegaly.  Multiple urticarial skin lesions with excoriation are seen on the upper and lower extremities.  There are no oral or genital lesions.
Laboratory results are as follows:

Which of the following would be most helpful in establishing a diagnosis in this patient?

Quizplus · Accepted Answer

This patient's clinical presentation suggests a serum sickness-like reaction associated with acute hepatitis B viral (HBV) infection. Acute HBV infection can present with mild flu-like symptoms or fulminant liver failure. In some patients, a serum sickness-like reaction (fever, rash, and symmetric polyarthralgias/arthritis) may develop, followed by jaundice and nonspecific systemic complaints. Serum sickness-like reaction is due to accumulation of antigen-antibody or immune complexes leading to vascular and cellular inflammation. The rash is usually pruritic and urticarial with no mucosal involvement. The symmetrical polyarthralgias/arthritis involves primarily small joints and may be associated with morning stiffness resembling that of rheumatoid arthritis. The rash and joint symptoms often resolve within 2-3 weeks followed by development of the icteric phase of HBV infection. Treatment is usually supportive. (Choice A) Although lupus can present with many of the symptoms described in this patient, urticarial skin lesions are unlikely. (Choice B) Early localized Lyme disease typically presents with nonspecific viral illness and erythema migrans. Serologic testing in the acute phase of Lyme disease is not helpful as IgM antibodies are not present for 2-6 weeks after infection. (Choice C) Epstein-Barr virus mononucleosis usually presents with fever, fatigue, lymphadenopathy, persistent exudative sore throat, and possible splenomegaly. The EBV heterophile test (Monospot) should be performed > 4 days after symptom onset to avoid false-negative test results. This patient's skin and joint findings make this less likely. (Choice E) Disseminated gonococcal infection usually presents with purulent arthritis without skin lesions or the triad of tenosynovitis, dermatitis (painless pustular lesions), and migratory asymmetric polyarthralgias. This patient's urticarial skin lesions and lymphadenopathy are less consistent with disseminated gonococcal infection. Educational objective: Acute hepatitis B viral (HBV) infection may be associated with serum sickness-like syndrome (fever, symmetric polyarthritis, and urticarial skin lesions without mucosal involvement). Diagnosis is confirmed by the presence of hepatitis B surface antigen. The rash and joint symptoms often resolve within 2-3 weeks followed by development of the icteric phase of HBV infection. Treatment is usually supportive. __________ References: Hepatitis B surface antigen deposition in the blood vessel walls of urticarial lesions in acute hepatitis B. (http://www.ncbi.nlm.nih.gov/pubmed/7236503) The extrahepatic manifestations of hepatitis B virus. (http://www.ncbi.nlm.nih.gov/pubmed/18760074) Extrahepatic manifestations of viral hepatitis. (http://www.ncbi.nlm.nih.gov/pubmed/242219)

A 29-Year-Old Previously Healthy Man Comes to the Physician with Malaise