Diagnosis and genotyping of melioidosis in a domestic cat in New Caledonia.

Abstract

OBJECTIVES: To report a case of melioidosis in a domestic cat in New Caledonia, describing the diagnostic, microbiological and molecular findings. To evaluate the potential of a glanders serological test for assessing exposure to Burkholderia pseudomallei. METHODS: A domestic cat presenting with respiratory symptoms underwent clinical and radiographic examination. Bacterial culture was performed on bronchoalveolar lavage fluid, and the strain was characterised using MALDI-TOF mass spectrometry and whole-genome sequencing. In silico multi-locus sequence typing (MLST) and phylogenetic analyses were also conducted. Serology was assessed using a commercial ELISA (GLANDA ELISA, IDVet), which was originally developed for diagnosing glanders. RESULTS: Burkholderia pseudomallei was isolated and sequenced, revealing ST2147, which has been previously identified in New Caledonia. Phylogenetic analysis confirmed clustering with strains from the Pacific region. The cat's serum tested strongly positive by ELISA, suggesting the potential of this test for assessing exposure to B. pseudomallei in cats and other animals. Screening of archived feline sera identified only one additional seropositive cat, suggesting low prevalence. CONCLUSIONS: This case supports the presence of multiple B. pseudomallei genotypes in New Caledonia and highlights the risk of melioidosis in cats. The commercial GLANDA ELISA shows promise as a tool for demonstrating animal exposure to B. pseudomallei, directing the need for culturing for confirmation of melioidosis. Enhanced awareness among veterinarians is essential for the early diagnosis and management of this disease in companion animals.