Snapshot A 4-year-old boy presents to the urgent care clinic for a new rash. His mother reports that the rash started on both his cheeks yesterday, but since then he has developed a rash on his trunk. On physical exam, he has a slapped cheeks appearance and has a maculopapular rash on his trunk with some areas having a lacy or reticular appearance. The physician advises him to stay home while he is still contagious and to stay away from pregnant women. Introduction Classification parvovirus B19 a nonenveloped, linear, single-stranded DNA virus causes a variety of diseases aplastic crisis in patients with red blood cell disorders pure red blood cell aplasia in adults rheumatoid arthritis-like symptom in adults erythema infectiosum (fifth disease) in children hydrops fetalis in fetuses if pregnant women are infected transmission via respiratory droplets Epidemiology Incidence highest in winter and spring Demographics children > adults Risk factors sickle cell disease thalassemia hereditary spherocytosis close proximity to others (e.g., school or daycare centers) ETIOLOGY Pathogenesis infects red blood cells through the P antigen viral replication in bone marrow causes the death of erythroid progenitor cells causes hydrops fetalis in fetuses due to severe fetal anemia Presentation Symptoms prodrome with flu-like symptom hydrops fetalis and fetal death in pregnant women polyarthropathy small joints (e.g., hands) - typically the only symptom in adults Physical exam erythema infectiosum first rash appears as slapped cheeks subsequent rash is an erythematous maculopapular rash on the trunk and limbs, which may appear reticular or lacy Studies Labs parvovirus-specific immunoglobulin M detection of parvovirus on polymerase chain reaction anemia Differential Measles distinguishing factors confluent maculopapular rash without slapped cheeks rash Koplik spots on buccal mucosa Rubella distinguishing factor non-confluent maculopapular rash that spreads from face to body DIAGNOSIS Making the diagnosis based on clinical presentation may be confirmed with laboratory studies Treatment Management approach mainstay of treatment is supportive care Conservative supportive care indication all patients modalities analgesics hydration Medical non-steroidal anti-inflammatory drugs indication polyarthropathy Complications Myocarditis Behcet syndrome Aplastic crisis
QUESTIONS 1 of 3 1 2 3 Previous Next Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK (M2.PD.17.4678) A 7-year-old Caucasian boy is brought to your clinic with a 2-day complaint of fatigue and easy bruising. The patient has been healthy up until this point, except for a cold 1 week before. On physical exam, the patient has the following appearance seen in Figure A. A complete blood count is performed and reveals the following significant values: WBC 7,000/mm^3, Hgb 8.0 g/dL, and PLT 200,000/mm^3. Further workup via hemoglobin electrophoresis reveals absent levels of HgS and normal levels of HgA2. Which of the following comorbidities is most likely in this patient? QID: 107267 FIGURES: A Type & Select Correct Answer 1 Vitamin D deficiency 0% (0/10) 2 Beta-thalassemia minor 30% (3/10) 3 Sickle cell disease 0% (0/10) 4 Human immunodeficiency virus (HIV) infection 10% (1/10) 5 Hereditary spherocytosis 60% (6/10) M 6 Question Complexity D Question Importance Select Answer to see Preferred Response SUBMIT RESPONSE 5 Review Tested Concept Review Full Topic (M2.PD.15.4694) A 7-year-old boy is brought in by his mother after he developed a rash, shown in Figure A. On interview, you learn that four days ago your patient had a fever of 100F, headache, coryza, and diarrhea. Besides the rash, the patient has no other complaints. It is recorded that his vaccinations are up-to-date. With regards to the rash, which of the following is the best treatment? QID: 107696 FIGURES: A Type & Select Correct Answer 1 Reassure parent that the rash is self-limiting 72% (13/18) 2 Red blood cell transfusion 28% (5/18) 3 Monoclonal antibody against tumor necrosis factor-alpha 0% (0/18) 4 Guanosine analog that leads to viral DNA polymerase inhibition 0% (0/18) 5 Vitamin A administration 0% (0/18) M 7 Question Complexity D Question Importance Select Answer to see Preferred Response SUBMIT RESPONSE 1 Review Tested Concept Review Full Topic