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strawberry tongue Pastia lines, bright red, orange, or even hemorrhagic lines, can occasionally be seen in the axillae or antecubital fossa The rash generally lasts to days, followed by brownish discoloration and peeling of the skin as small flakes to entire casts of the digits A rapid streptococcal test or throat culture confirms infection Epstein–Barr Virus Between 5% and 15% of patients with Epstein–Barr viral infection, otherwise known as infectious mononucleosis, will have an erythematous maculopapular eruption Infection in young children is usually asymptomatic or so mild that diagnosis is not sought Older patients between 15 and 25 years of age are more likely to present for evaluation Fifty percent to 100% of patients with infectious mononucleosis develop a maculopapular rash after receiving concurrent ampicillin or amoxicillin-containing antibiotics—most commonly for an incorrect diagnosis of streptococcal pharyngitis The illness begins insidiously with headache, malaise, and fever, followed by sore throat, membranous tonsillitis, and lymphadenopathy Splenomegaly is common The exanthem occurs within to days as a macular or maculopapular morbilliform eruption most prominent on the trunk and proximal extremities An enanthem consisting of discrete petechiae at the junction of the hard and soft palate occurs in approximately 25% of patients Diagnosis is often presumed clinically but may be supported by an absolute increase in atypical lymphocytes or a positive heterophile antibody (monospot) test (obtained after the first week of symptoms), or may be confirmed by serology The heterophile antibody test is less sensitive in children younger than years of age The illness is most commonly self-limited, requiring no therapy, but due to the frequency of associated splenomegaly, affected children should not be allowed to participate in contact sports until fully recovered and the spleen is no longer palpable Mycoplasma Infections Infections with Mycoplasma pneumoniae may cause morbilliform rashes in up to 15% of cases The classic clinical presentation is of a child with malaise, lowgrade fever, and prominent cough The cough is initially nonproductive but may become productive, particularly in older children, and may persist for to weeks Physical examination may reveal bilateral rales Diagnosis is suggested by mycoplasma PCR of the sputum or by IgM or IgG titers of the blood Erythromycin, clarithromycin, or azithromycin are the treatment of choice Mycoplasma can also induce Stevens–Johnson syndrome (see Chapter 68 Rash: Drug Eruptions ) The rash here is characterized by hemorrhagic lips and mucosal involvement with fewer bullous lesions on the rest of the skin and is thus sometimes referred to as Mycoplasma pneumoniae-associated mucositis Roseola Infantum Roseola infantum, also called exanthem subitum or sixth disease , is attributed to primary infection with human herpes virus (HHV)-6 The illness is characterized by the onset of a maculopapular rash that appears following a 3- to 4-day febrile illness The fever is characteristically high The rash is widely disseminated, appearing as discrete, small, pinkish macules that rarely coalesce, beginning on the trunk and then extending peripherally The rash may last for hours to days The occurrence of the rash within 24 hours of defervescence rather than the morphologic appearance of the rash itself leads to the correct diagnosis The rash can appear very similar to that seen in measles, but the child with roseola appears well and is no longer febrile Diagnosis is made clinically and care is supportive Disseminated Neisseria Gonorrhoeae Disseminated Neisseria gonorrhoeae should be considered in sexually active or potentially abused children, especially if associated with a history of vaginal or penile discharge A distinct minority of patients develop disseminated gonorrhea infection through hematogenous spread Disseminated gonorrhea may cause a range of cutaneous lesions, including small erythematous papules, petechiae, or vesicle-pustules on a hemorrhagic base These cutaneous lesions usually develop on the trunk but may occur anywhere on the extremities An etiologic diagnosis can be established by demonstration of the organism on Gram stain of the skin lesion, positive blood culture, or positive culture of oral or genital sites Based on resistance patterns, recommended current therapy is ceftriaxone 50 mg/kg/day (maximum g/day) until clinical improvement is seen, at which point it can be changed to an oral antibiotic, such as cefixime, ciprofloxacin, ofloxacin, or levofloxacin, for a total of a 7-day course Quinolones should not be used for infections in men who have intercourse with men or in those with a history of recent foreign travel or partners’ travel, or infections acquired in other areas with increased resistance Concomitant sexually transmitted diseases should be sought and treated Secondary Syphilis One needs a high level of suspicion when viewing rashes in sexually active (or potentially abused) children to make the diagnosis of secondary syphilis, caused by the spirochete Treponema pallidum Manifestations of secondary syphilis usually occur to weeks after the appearance of the primary lesion, which may have gone unnoticed The exanthem extends rapidly and is usually pronounced The rash of secondary syphilis is characterized by a generalized cutaneous eruption, usually composed of brownish, dull-red macules or papules that range in size from a few millimeters to cm in diameter ( Fig 88.20 ) They are generally discrete and symmetrically distributed, particularly over the trunk, where they follow the lines of cleavage in a pattern similar to pityriasis rosea Papular lesions on the palms and soles, as well as the presence of systemic symptoms, such as general malaise, fever, headaches, sore throat, rhinorrhea, lacrimation, and generalized lymphadenopathy, help differentiate secondary syphilis Acquired syphilis is sexually contracted from direct contact with ulcerative lesions of the skin or mucous membranes of an infected individual Diagnosis may be presumed after a positive nontreponemal test, such as the VDRL slide test, rapid plasma reagin (RPR) test, or the automated reagin test Diagnosis should be confirmed by a treponemal test, such as the fluorescent treponemal antibody absorption test, the microhemagglutination test for T pallidum , or the T pallidum immobilization test Definitive diagnosis may also be made by identifying spirochetes by microscopic dark-field examination or direct fluorescent antibody tests of lesion exudate or tissue Penicillin is the treatment of choice unless contraindicated, in which case tetracycline, doxycycline, ceftriaxone, or erythromycin may be substituted Length of therapy should be based on duration and stage of infection Concomitant sexually transmitted diseases should be sought and treated empirically HIV testing is recommended for patients with secondary syphilis FIGURE 88.20 Secondary syphilis Nonspecific Viral Exanthems Many times, a specific diagnosis cannot be made, given the large number of viruses that can be associated with macular or morbilliform eruptions In particular, enteroviruses and adenoviruses can cause a macular or morbilliform eruption There is little to distinguish the rash caused by one of these viruses from that of another, based on the location and morphology, with the exception of those viral infections previously discussed One usually arrives at the diagnosis of