Heightened vigilance needed to solve persisting enigma of melioidosis cases in Kansas, Minnesota and Texas

On June 30, 2021, CDC issued a Health Advisory via its Health Alert Network stating: “The Kansas Department of Health and Environment, the Texas Department of State Health Services, and the Minnesota Department of Health, with assistance from the Centers for Disease Control and Prevention (CDC), are investigating three cases of Burkholderia pseudomallei (melioidosis) infections. Based on genomic analysis, these three cases (one male, two females; two adults and one child) may share a potential common source of exposure. The first case, identified in March 2021, was fatal. Two other patients were identified in May 2021, one of whom is still hospitalized. One has been discharged to a transitional care unit. None of the patients’ families reported a history of traveling outside of the continental United States.” At least one of the patients was “later diagnosed with infectious encephalitis.” Encephalitis is very rare manifestation of melioidosis. The more common four syndromes involve the skin, the lung, the bloodstream and the liver-spleen-kidneys. Now, over two months later, no epidemiological link has been reported for why these three persons in three states would have a “potential common source of exposure.” If an autopsy was performed, the results have not yet been made public. The basis for the rare diagnosis “infectious encephalitis” due to B. pseudomallei was not specified as to whether it was based on CSF findings, radiologic changes or both. Certainly, there could have been several more than these three patients, given that this gram-negative is often misidentified with other organisms. The CDC Health Advisory stated: “Consider re-evaluating patients with isolates identified on automated systems as Burkholderia spp. (specifically B. cepacia and B. thailandensis), Chromobacterium violaceum, Ochrobactrum anthropi; and, possibly, Pseudomonas spp., Acinetobacter spp., and Aeromonas spp. Laboratory testing involving automated identification algorithms (e.g., MALDI-TOF, 16s, VITEK-2) may misidentify B. pseudomallei as another bacterium. The isolate from the Texas case was initially misidentified as B. thailandensis by MALDI-TOF.” Further details on the disease, its epidemiology, history, risk to laboratory workers and prolonged multi-drug treatment regimens are cited in this June 30 CDC document. CDC also references clinical management with hundreds of cases in northern Australia (Darwin).