Case Presentation: A 48-year-old female with a history of cyclic vomiting syndrome, gastroparesis, postural orthostatic tachycardia syndrome (POTS), opioid dependence, and a right-sided Port-A-Cath presented with two days of generalized weakness, a witnessed seizure-like episode, and a fall. Initial trauma evaluation was unremarkable. Laboratory studies revealed leukocytosis (WBC 20.8), thrombocytosis (platelets 648), mild hyponatremia (Na 134), lactic acidosis (3.8), and acute kidney injury (creatinine 1.5). She was hypotensive on arrival but improved after 2 liters of lactated Ringer’s. CT abdomen and pelvis suggested colitis.She was admitted for management of intractable nausea and vomiting and suspected sepsis given leukocytosis, tachycardia, and renal dysfunction. Blood cultures were obtained peripherally and from the Port-A-Cath. Empiric ciprofloxacin and metronidazole were initiated; ciprofloxacin was later changed to ceftriaxone. Peripheral cultures grew Corynebacterium pseudodiphtheriticum in 1 of 2 bottles at 33 hours, prompting escalation of ceftriaxone to 2 g daily. Repeat peripheral cultures were negative. Infectious Disease was consulted.On hospital day 2, Port-A-Cath cultures grew Pseudomonas putida, raising concern for catheter-associated bloodstream infection. Antibiotics were broadened to cefepime and vancomycin. Given the port culture results, Cardiology was consulted for possible endocarditis. Transthoracic echocardiogram revealed tricuspid valve vegetations, confirmed by transesophageal echocardiogram. The Port-A-Cath was removed, cefepime discontinued, and a 6-week course of intravenous vancomycin was completed via PICC line. The patient’s clinical status improved following port removal, and a Hickman catheter was later placed for long-term access. Follow-up echocardiography was planned two weeks post-discharge.
Discussion: This case demonstrates several unusual features. C. pseudodiphtheriticum is a rare cause of native valve endocarditis, with most reports describing left-sided involvement and a male predominance (3). Our patient, a middle-aged woman without structural heart disease or prosthetic valves, developed right-sided tricuspid valve endocarditis likely secondary to her indwelling Port-A-Cath.The simultaneous isolation of C. pseudodiphtheriticum from peripheral cultures and P. putida from the catheter complicated the identification of the primary pathogen. Given tricuspid valve vegetations, clinical improvement after port removal, and targeted antimicrobial therapy, C. pseudodiphtheriticum was determined to be the causative organism. This highlights the importance of not dismissing Corynebacterium species as contaminants, particularly when isolated from multiple cultures in clinically compatible contexts.Our patient improved with medical management alone. Surgical intervention was deferred given her hemodynamic stability, absence of abscess formation, and vegetations less than 2 cm.
Conclusions: This case highlights the importance for clinicians to recognize that Corynebacterium species isolated from blood cultures, particularly in patients with indwelling catheters, should not be automatically dismissed as contaminants. Early echocardiography and prompt removal of infected devices, combined with appropriate antimicrobial therapy, are critical for effective management and favorable outcomes.