Medical imaging in melioidosis - 20-year experience in a non-endemic Australian city.

Introduction: Melioidosis may occasionally be encountered in non-endemic areas and medical imaging is frequently used to identify and characterise sites of disease. The purpose of this study is to describe the spectrum of imaging findings encountered in melioidosis patients treated in the tertiary public hospitals of Perth, Western Australia, between 2002 and 2022.

Methods: A database search and electronic medical record review was used to identify cases. Cases were included if they had Burkholderia pseudomallei isolated on culture and if they had at least one diagnostic imaging study performed at a Perth public tertiary hospital. The relevant imaging studies were reviewed, and imaging findings were recorded.

Results: Thirty-six cases were identified. The most common disease manifestation was bacteraemia (72%, 26 cases), followed by pulmonary infection (58%, 21 cases), skin and soft tissue infection (22%, eight cases), prostate abscess (14%, five cases) and septic arthritis (6%, two cases). A previously unreported case of isolated melioid pleural effusion was identified, as was a case of reactivated chronic latent pulmonary melioidosis with an apparent delay of over 20 years between the onset of symptoms and the time of infection. In cases with pulmonary melioidosis, the major lung abnormalities on CT chest could be categorised into one of two distinct patterns: nodular-predominant (78%) or consolidation-predominant (22%).

Conclusion: Further research is required to assess the utility of the pattern-based categorisation of lung abnormalities on CT chest seen in the pulmonary melioidosis cases of this series.