Superficial Cat Bite on Wrist with Early Localized Erythema

Case at a Glance

A healthy 35-year-old male presented with concern over a superficial cat bite on his wrist sustained approximately 15 hours prior. Despite immediate wound cleansing, localized erythema developed, prompting evaluation for infection risk, particularly due to the location on the wrist.

Patient's Story

The patient, a healthy 35-year-old with no significant medical history or current medications, was handling his indoor cat. When he picked up the animal to move it, the cat reacted by digging its claws into his arm and inflicting a minor bite on his left wrist. The patient described the bite as a 'superficial knick' rather than a deep puncture. He immediately cleansed the bite and associated scratches with 3% hydrogen peroxide and applied a topical antibiotic ointment. Approximately 15 hours later, he noted a circular area of redness, about 1 cm in diameter, surrounding the bite mark. He was concerned about the potential for infection, especially given the bite's proximity to the major blood vessels of the wrist.

Initial Assessment

On presentation, the patient was afebrile and in no acute distress. Examination of the left volar wrist revealed a single, small puncture wound consistent with a cat's canine tooth. Surrounding the puncture was a non-indurated, blanching erythematous patch measuring approximately 10 mm in diameter. There was no significant edema, purulent drainage, or warmth to the touch beyond the immediate area. Several linear, superficial scratches were also noted on the forearm, without signs of infection. Range of motion of the wrist and fingers was full and painless. Distal neurovascular status was intact.

The Diagnostic Journey

The diagnosis was primarily clinical. Given the history of a cat bite, a high index of suspicion for infection with organisms such as Pasteurella multocida was maintained. Although the wound was superficial and systemic signs of infection were absent, the location on the wrist (a high-risk area due to underlying tendons and poor vascularity of some structures) and the development of early cellulitis (localized erythema) within 24 hours warranted consideration for treatment. The discussion centered on the risks and benefits of prophylactic antibiotics versus a 'wait-and-see' approach with close monitoring. The patient's concern and the typical virulence of oral feline flora guided the decision toward intervention.

Final Diagnosis

Early localized cellulitis secondary to a cat bite on the wrist.

Treatment Plan

Considering the high risk of infection associated with cat bites, especially on the hand or wrist, a course of prophylactic antibiotics was prescribed. The patient was started on amoxicillin-clavulanate 875/125 mg twice daily for 7 days. He was instructed on proper wound care, including gentle daily cleansing with soap and water and keeping the area clean and dry. He was also advised on signs of worsening infection that would necessitate immediate re-evaluation, such as expanding redness, increased swelling or pain, purulent discharge, or the onset of fever.

Outcome and Follow-up

The patient was advised to follow up if symptoms did not begin to improve within 24-48 hours. A telephone follow-up was conducted 48 hours after the initial visit. The patient reported that the redness around the bite had significantly decreased and had not spread. He denied any increase in pain, swelling, or any systemic symptoms. He completed the full 7-day course of antibiotics without complications. At a final check, the wound had healed completely, leaving only a minuscule mark.