Case Study: Suspected Steven-Johnson Syndrome and Toxic Epidermal Necrolysis caused by Amoxycilin-clavulanic acid in Cat

Abstract

Background: Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are variations of immune-mediated diseases. SJS/TEN has been rarely reported in cats and has consistently been linked to drugs.

Objective: This study aims to report and describe SJS/TEN cases in cats.

Case Description: A 5-year-old female domestic short-hair cat presented with multifocal cutaneous necrolysis and infection in the abdominal area. Based on clinical presentation this case was initial diagnosed as urine scald. Surgery was performed to remove the necrotic skin. During the surgery, multifocal erythema patches were observed on the right flank side of the abdomen.

Test Result and Diagnosis: The emergence of new lesions resembling it raises suspicion of a possible allergic reaction to a substance, including a medication allergy, Unfortunately, there is no definitive diagnostic test for SIS/TEN. The ALDEN algorithm and the Naranjo scale were used to assess amoxicillin-clavulanic acid, yielding an ALDEN score of 7 and a Naranjo scale score of 6, suggesting a probable reaction. Several tests were also conducted, including a complete blood count, and bacterial culture to rule out several possibilities and for treatment consideration.

Treatment: Cyclosporine (7mg/kg) was administered as an immunosuppressant, and wound cleansing was managed using normal saline. No new skin lesions appeared after stopping the antibiotic and administering cyclosporine; unfortunately, the infection worsened.

Conclusion: The differential diagnosis for this case is with skin cancer, adverse drug reaction, bacterial infection, and erythema multiforme. Amoxicillin-clavulanic acid is identified as a very probable cause of SJS/TEN based on the ALDEN algorithm and the Naranjo scale.