summary Dog and Cat Bites to the hand are common and are associated with secondary infections due to a large number of animal oral flora pathogens. Diagnosis is often delayed and is confirmed with a careful history and physical examination. Treatment is generally oral antibiotics but presence of soft tissue infection, abscess or tenosynovitis requires urgent irrigation and debridement. Epidemiology Incidence (dog > cat > human) dog bites are most common animal bites in the US (90%) dog is known to victim in 90% of cases cat bites are 2nd most common (10%) human bites are 3rd most common Demographics more common in males more frequent at ages 2-19 years Anatomic Location upper extremity > lower extremity Etiology Pathophysiology mechanism dog bites login to view 3 more bullets cat bites login to view 4 more bullets microbiology most infections are polymicrobial, with > 1 anerobe most common isolate from both cats and dogs is Pasteurella sp. login to view 3 more bullets dog bites login to view 10 more bullets cat bites login to view 4 more bullets Associated conditions secondary bacterial infection most bites do not become infected risk factors for infection login to view 10 more bullets rabies caused by a rhabdovirus common animal carriers include dogs, raccoons, bats, foxes increased risk with open wounds, scratches/abrasions, mucous membranes Presentation History important to determine type of animal time since injury presence of comorbidities Symptoms pain and swelling bleeding signs of local or systemic sepsis Physical Exam evaluate depth of puncture wound and presence of crush injury check for neurovascular status look for joint penetration important to photograph wounds Imaging Radiographs indications to obtain crush injuries suspected fracture suspected foreign body Studies Culture indications if signs of infection are present routine culture not indicated technique deep aerobic and anaerobic culture Diagnosis Clinical diagnosis is made with careful history and physical examination Treatment Nonperative copious irrigation, prophylactic antibiotics, tetanus toxoid, +/- rabies prophylaxis copious irrigation in emergency room login to view 2 more bullets indications for antibiotics login to view 9 more bullets rabies prophylaxis login to view 3 more bullets immobilization login to view 1 more bullet Operative formal surgical debridement indications login to view 6 more bullets Prognosis Serious and fatal bites include large, aggressive dogs small children head and neck bites