Introduction: Genital ulcers are rare in pediatric age; they affect predominantly adolescents, causing concern and discomfort in the patients and their families. We report the case of a 14-years-old girl who came to our Emergency Department (ED) for vulvar ulcers and fever. Case description: A 14-years-old girl presented to our ED for a 5-day fever associated with a vulvar ulcer, malaise, dysuria with urinary retention. She had started oral acyclovir and amoxicillin-clavulanate two days before. Five months before she presented a similar episode. She denied any kind of sexual contact or trauma. Physical examination revealed a deep and painful ulcer of about 1.5 cm in diameter on the left minor labium, covered with fibrin, necrotic tissue, and purulent exudate. Specularly, on the inner right lip there was a small superficial ulcer of 3 mm in diameter. She had hyperemic pharynx, bilateral laterocervical and inguinal polyadenopathy. Blood tests showed increase in blood lymphomonocytes, inflammatory markers and transaminases; the pharyngeal antigenic swab for SARS-CoV2 was positive. EBV serology was compatible with acute primary infection. Serology for CMV, HSV 1-2 and Treponema, ANA, Rheumatoid factor, C3, C4, IgA, IgG, IgM, lymphocyte subpopulations, HLA-B5, B51, B27 and thyroid function tests were normal. Anti thyroid peroxidase and anti TSH receptor antibodies were positive. On the ulceral swab, PCR was positive for EBV and negative for HSV 1-2, CMV and SARS-CoV-2. Vulvar swab culture detected the presence of Escherichia coli, Enterococcus faecalis and Candida albicans. Fundus oculi and pathergy test were negative. A Lipschütz's ulcer during primary infection of EBV in concomitant SARS-CoV2 infection was suspected. The ulcers were treated with impregnated gauzes and hygiene. Antibiotic therapy was continued, and fluconazole was added, given the bacterial superinfection of the ulcer. Oral acyclovir was discontinued. Urinary catheter was kept in place until disappearance of dysuria (4 days). Multidisciplinary approach was required. Fever disappeared on the 11th day after disease onset. Vulvar ulcers completely healed in three weeks. The girl was referred to the Immuno-rheumatologically Center for follow up. Discussion: Genital ulcers in adolescents are most commonly referred to sexually transmitted infections, causing embarrassment and possibly compromising communication between the young patient and the doctors. However, vulvar ulcers can be caused by other conditions: our case shows that Lipschütz Ulcer, an unusual diagnosis in Pediatric ED, should not be neglected and has to be suspected in presence of a concomitant viral infection. It remains a diagnosis of exclusion: if episodes recur, careful follow-up is needed to rule out other causes, such as autoimmune or auto inflammatory diseases.