Hidden in Plain Sight: Ralstonia mannitolilytica as a Rare Cause of Urinary Tract Infections

Children admitted to hospitals have been shown to frequently suffer from urinary tract infections (UTIs), with <i>Escherichia coli</i> being the most common cause. <i>Ralstonia mannitolilytica</i> is commonly found in plants, soil, and water sources. Since <i>Ralstonia</i> species are resistant to many antimicrobials, such as carbapenems, treating an infection with <i>R. mannitolilytica</i> is challenging. We present an unusual case of a five-month-old infant with a posterior urethral valve whose urine culture showed the growth of a rare organism called <i>R. mannitolilytica</i>. UTIs associated with <i>R. mannitolilytica</i> are still relatively uncommon. With its high mortality rates, despite antibiotic treatment, this unusual organism needs to be considered in the immunocompromised population presenting with rapidly progressing infections.