Development of Vesicular Lesions During Antibiotic Treatment for Lower Extremity Cellulitis
Case at a Glance
A 22-year-old female developed vesicular lesions on her right lower extremity three days after initiating antibiotic therapy for cellulitis, raising concerns about treatment response, drug reaction, or alternative diagnosis.
Patient's Story
The patient presented with a chief complaint of new vesicular lesions developing on her right leg. She reported being diagnosed with cellulitis of the right lower extremity three days prior and had immediately started oral antibiotic therapy as prescribed. Two days into treatment, she noticed the appearance of small fluid-filled vesicles on the affected leg. By the following morning, these lesions had increased in number and distribution, remaining localized to the previously infected limb. The patient was concerned about whether this represented normal healing, treatment failure, or a complication requiring immediate medical attention.
Initial Assessment
Upon initial evaluation, the patient appeared well with stable vital signs. Physical examination revealed multiple small vesicular lesions distributed across the right lower extremity. The vesicles contained clear to purulent fluid and were tender to palpation. The surrounding skin showed signs consistent with the previously diagnosed cellulitis, including erythema and warmth. No systemic signs of infection or allergic reaction were noted at the time of assessment.
The Diagnostic Journey
The clinical presentation posed several diagnostic considerations. The development of vesicular lesions during antibiotic treatment for cellulitis was atypical and required careful evaluation. Differential diagnoses included: adverse drug reaction to the prescribed antibiotic, contact dermatitis from topical applications, viral infection (such as herpes simplex), bacterial superinfection, or an alternative diagnosis that may have been initially misdiagnosed as cellulitis. The temporal relationship between antibiotic initiation and vesicle development was particularly noteworthy.
Final Diagnosis
Based on the clinical presentation and photographic documentation, the case represented either an adverse cutaneous drug reaction to the antibiotic therapy or a concurrent viral infection. The vesicular pattern was not consistent with typical cellulitis progression, suggesting either a medication-related eruption or a misdiagnosis of the original condition.
Treatment Plan
The patient was advised to discontinue the current antibiotic and seek immediate follow-up with her primary care physician or dermatologist for in-person evaluation. Symptomatic care with cool compresses and avoidance of irritants was recommended. Culture of vesicle fluid was considered to rule out bacterial or viral etiology. Alternative antibiotic therapy would be considered only after proper evaluation and identification of the underlying cause of the vesicular eruption.
Outcome and Follow-up
The patient was strongly advised to seek urgent medical follow-up due to the atypical presentation. The development of vesicular lesions during cellulitis treatment warranted immediate reassessment to rule out drug reaction, alternative diagnosis, or treatment complications. Close monitoring was essential to prevent potential progression or systemic involvement.