Prosthetic Hip Infection Secondary to <i>Morganella morganii</i>: A Rare, Morbid Condition

<b>Background/Objectives:</b> Periprosthetic joint infection (PJI) is a challenging problem in orthopedic surgery and is often associated with high morbidity. The treatment becomes even more challenging whenever the microorganism is virulent and/or not widely known as a causative organism on these occasions. This study aims to report on the clinical outcomes of hip hemiarthroplasty prosthetic hip joint infection by an atypical, rare microorganism, <i>Morganella morganii</i> (<i>M. morganii</i>), focusing on morbidity, revisions, and mortality. <b>Methods:</b> This is a retrospective series of four cases of prosthetic joint infections with <i>Morganella morganii</i>, a rare Gram-negative opportunistic facultative anaerobic pathogen, in four patients who received hip hemiarthroplasty for displaced femoral neck fractures at a level 1 trauma center. Clinical notes, laboratory findings, and radiographs were reviewed to extract relevant information regarding the history and outcomes. <b>Results:</b> The patients were four females, with a mean age of 84.27 years at the time of surgery. Two cases (50%) underwent surgical debridement and implant retention, followed by lifelong antibiotic suppression for symptomatic control of persistent wound drainage, and the other two underwent implant removal and resection arthroplasty (one patient) or received an antibiotic spacer (one patient), followed by chronic antibiotic therapy until wound closure. <b>Conclusions:</b> Periprosthetic hemiarthroplasty infection secondary to <i>M. morganii</i> was associated with overall poor outcomes. Antibiotic suppression could be a reasonable option after the surgical debridement or implant removal in <i>M. morganii</i> PJI to control the symptoms.