Unilateral Laterothoracic Exanthema

A 10-year-old Caucasian boy was referred for evaluation of an acute eruption that had developed over the past 8 days. The began in right popliteal fossa, and then coalesced spread along side his body. fever up to 38°C joint pain were reported 3 days before appearance skin lesions. Physical examination showed erythematous edematous macules papules on hemibody (Figure). left did not show any Laboratory testing IgM positivity parvovirus B19. Unilateral laterothoracic exanthema diagnosed. Oral antihistamine (loratadine 10 mL/day) emollients prescribed. Follow-up at weeks complete resolution symptoms. is typically starts around axilla or hollow.1Mendelsohn S.S. Verbov J.L. Asymmetric periflexural exanthem childhood.Clin Exp Dermatol. 1994; 19: 421Crossref PubMed Scopus (12) Google Scholar There no dominance. It usually spreads affected hemibody, lesions coalesce form large erythematous-edematous plaques. often becomes more generalized, but always maintains a unilateral predominance. Usually, itching predominant symptom. self-limited process lasting 3-6 weeks. diagnosis fundamentally clinical, because it does require biopsy. Serologic study negative, although there are authors who postulate relationship between viral infection rash, such as B19 influenza virus, among others.2Guimerá-Martínn-Neda F. Fagundo E. Rodríguez Cabrera R. Sánchez García M. et al.Asymmetric childhood: report two cases with B19.J Eur Acad Dermatol Venereol. 2006; 20: 461-462Crossref (22) Scholar,3Cohen-Sors Dadban A. Pezron J. Lok C. childhood virus infection.Dermatol Online 2020; 26: 13030PubMed main differential Gianotti-Crosti syndrome, this syndrome symmetrical, face extremities being area's most commonly affected. antihistamines soothing lotions first treatment recommendation.