Herein we report a case of Lyme borreliosis in a pediatric patient, highlighting the diagnostic challenges associated with this condition. An 11-year-old girl was admitted with high fever, headaches, abdominal pain, and a progressing rash. Initial symptoms included small rashes that vanished with antihistamine treatment, but maculopapular rashes later emerged on the trunk and limbs, prompting further investigation. Differential diagnosis included toxic erythema, Stevens-Johnson syndrome, and Lyme borreliosis. Despite no reported tick bite and initial doubt due to the season, Lyme borreliosis was confirmed by serologic testing, diagnosing the patient with early disseminated Lyme disease. The diagnostic complexity was increased by the rash’s atypical presentation – large, homogeneous papular rashes. This case emphasizes the necessity for physicians to adeptly gather detailed histories and employ thorough, up-to-date diagnostic methods. Effective correlation of clinical findings with laboratory results and ongoing patient observation proved critical for an accurate diagnosis. This report underscores the importance of recognizing atypical presentations of Lyme borreliosis in children and the need for careful differential diagnosis.