This case report describes Pasteurella multocida illness in a woman who initially presented to a clinic with progressive left shoulder pain and functional limitation. The patient was empirically treated with antiinflammatory drugs, with no clinical response. She presented again with fever and warmth, tenderness, and swelling on the upper shoulder and was admitted to the hospital with leukocytosis, a high erythrocyte sedimentation rate, and high C-reactive protein levels. Findings on MRI were consistent with septic arthritis, and the patient began receiving amoxicillin-clavulanic acid therapy. She developed septic shock with associated hypotension, renal failure, and disseminated intravascular coagulation. The shoulder was surgically drained and cultures were positive for P multocida. Imipenem therapy was instituted and the patient had a full clinical recovery. There was no obvious cause for the aggressive sepsis. However, the patient revealed that she had previously sustained scratches in the affected shoulder area from her household cat, which were confirmed on physical examination. P multocida is a common commensal organism in the nasopharynx of many animals, including cats. P multocida infections frequently occur in response to cat bites and scratches, although systemic sepsis is rare. Patients who develop complications after such scratches usually have underlying disease, which was not evident in this patient. The patient was elderly and had a delayed diagnosis, both of which could have contributed to the aggressive progression.

This article emphasizes the importance of rapid examination, diagnosis, and treatment of pet bites and scratches in clinical practice, particularly among immunocompromised, elderly, and young individuals. The report is particularly relevant in our field because of continuous exposure to P multocida ourselves and by our clients. Veterinarians should advise clients to seek medical care for bites and scratches sustained outside the clinical setting.

Pasteurella multocida septic shock after a cat scratch in an elderly otherwise healthy woman: A case report. Fernandez-Valencia JA, Garcia S, Prat S. AM J EMERG MED 26:380.e1-380.e3, 2008.