Retrospective Analysis of Cases of Probable Canine Cutaneous Toxic Shock Syndrome for Clues to Facilitate an Early Diagnosis.

Background: Cutaneous toxic shock syndrome (CTSS), attributed to staphylococcal and streptococcal exotoxins, causes diffuse erythroderma and peripheral oedema with fatal systemic complications. In human medicine, a published list of scoring criteria exists where higher scores correlate with an increased likelihood of CTSS.

Objectives: To describe clinical and clinicopathological findings in canine CTSS and to determine the validity of the human TSS criteria score in dogs.

Animals: Seven client-owned dogs were treated at two veterinary teaching hospitals between 2003 and 2023.

Methods: Dogs with histopathological lesions of coalescing panepidermal cytotoxic dermatitis with neutrophilic satellitosis were included.

Results: Diagnosis was made antemortem in four of seven and postmortem in three of seven. Prodromal clinical signs included lethargy (seven of seven), vomiting and/or diarrhoea (three of seven) and inappetence (three of seven). Primary skin lesions included diffuse erythroderma (seven of seven), ventral oedema (seven of seven), distal limb oedema (six of seven) and vesicles/bullae of the concave pinnae (three of seven), ventrum (one of seven) and perianally (one of seven). Clinicopathological changes included anaemia (seven of seven), neutropaenia (two of seven), neutrophilia (five of seven), hypoalbuminaemia (seven of seven), thrombocytopaenia (seven of seven), increased liver enzymes (six of seven) and azotaemia (four of seven). Blood cultures were negative in five of five dogs and the source of infection was not identified in any dog. Five of seven dogs died or were euthanised and had higher scores using human criteria than the remaining two dogs; these two survived with supportive care and antibiotics.

Conclusions and clinical relevance: CTSS should be a differential diagnosis in dogs with the above prodromal signs before sudden onset of erythroderma, because early diagnosis is critical to survival. The human TSS criteria score could aid in earlier detection of canine CTSS.