Mycoplasma edwardii (M. edwardii) is an anthropozoonotic microorganism found in the upper respiratory and urogenital tracts of dogs. M. edwardii was one of the microbes isolated from peritoneal fluid of a 10-year-old child diagnosed with polymicrobial peritonitis following a puncture of dialysis tubing by a pet dog. Other unique pathogens representative of canine oral microflora isolated from this patient on peritoneal dialysis were Kingella denitrificans, Actinomycetes species and Capnocytophaga cynodegmi.