Case Presentation: Neisseria sicca is a gram-negative diplococcus that colonizes the nasopharynx. Severe infections, including bacteremia, from Neisseria sicca are very rare. We present a case of an immunocompromised 51-year-old female that was admitted with Neisseria sicca bacteremia complicated by an acute renal transplantation rejection.A 51-year-old female with a past medical history notable for type one diabetes mellitus, status post pancreatic and renal transplant (2013) on long-term immunosuppression presented to the emergency department with complaints of nausea, vomiting, and diarrhea. Our patient was found to have an acute cellular rejection of her right kidney transplant and was scheduled to undergo placement for a hemodialysis (HD) catheter. Her vital signs were normal, except for tachycardia. Physical examination revealed an ill-appearing middle-aged female, in moderate distress, who was unable to speak full sentences. Cardiac examination revealed a pansystolic murmur. Laboratory investigations revealed uremic acidemia and an anion gap of 18. Chest x-ray revealed nonspecific bilateral infiltrates. With her history of long-term immunosuppression, gastrointestinal complaints, and chest x-ray findings, pan-cultures were obtained, and broad-spectrum antibiotics were started. She underwent a left femoral permacath insertion and HD was initiated. Several days later, blood cultures revealed gram-negative bacteremia, which grew N. sicca. TEE was negative for endocarditis. Antibiotic coverage was narrowed to IV ceftriaxone for a 14-day course. Considering the bacteremia, she underwent removal of the left femoral permacath. Her bacteremia resolved and she was discharged home.

Discussion: Neisseria sicca rarely causes invasive infections, such as bacteremia. Neisseria sicca differs from Neisseria meningitidis and Neisseria gonorrhoeae because it lacks virulent factors such as lipopolysaccharides and fimbriae; this limits its pathogenicity. Nevertheless, in immunosuppressed patients with indwelling catheters, invasive infections are possible. Emerging research has suggested that indwelling catheters increase the risk of invasive infections. The exact pathophysiology remains unclear. Furthermore, bacteremia increases the risk of total graft failure, death-censored graft failure, and death with graft function. Appropriate antimicrobial management is paramount. Treating bacteremia of kidney transplant recipients requires at least 14 days of antibiotic therapy. Neisseria sicca is sensitive to penicillins, cephalosporins, and macrolides, and our patient received 14 days of ceftriaxone.

Conclusions: Neisseria sicca bacteremia is a life-threatening infection that is more common in immunocompromised patients with indwelling catheters. Appropriate antimicrobial selection and management are imperative in solid organ transplant recipients with bacteremia, as bacteremia increases the risk of total graft failure and death-censored graft failure.