This case report details the rare occurrence of Salmonella abscess in a failed kidney transplant. A 53-year-old Jamaican American woman with diabetes type 2 back on dialysis after failure of a kidney transplant presented with a 2 month history of decreased appetite and fatigue subsequently developing malaise and fevers. Evaluation with MRI showed an abscess that engulfed the previous kidney transplant location. After percutaneous drainage, culture of abscess grew Salmonella enteric subspecies sero type Group O: 47, 48 or 50. The patient was sent home on IV antibiotics with subsequent follow-up and drain removal. Although Salmonella abscesses in failed kidney transplant are rare, appropriate treatment can be conservative, similar to other renal abscesses.
An abscess in the kidney is due to salmonellae are rare in the literature and rarer in kidney-transplant patients. The etiology of such abscesses can be difficult to decipher. Salmonella enteric subspecies I serotypes can cause disease in a range of hosts depending on their adaptations. Human host restricted serotypes of typhi, paratyphi A and sendai tend to cause more systemic infections as they are thought to be more adapted to their host. Unrestricted host Salmonella species usually include typhirium and enteritidis and mostly cause self-limited gastroenteritis symptoms but in a range of higher vertebrates . The CDC estimates there are 1.2 million Salmonella infections per year with surveillance data indicating Salmonella serovar enteritidis being the most common serotype followed by Salmonella serovar typhimurium and Salmonella serovar newport. Chicken eggs are known source of these salmonellae outbreaks [2,3]. The patient’s history presents a compelling possibility of a previous systemic infection of Salmonella prior to presentation that could have seeded her kidney transplant leading its destruction via abscess. Although full sero typing was not completed, O antigen reactivity did not indicate it was from one of the common subspecies found on surveillance data. Successful treatment included systemic antibiotics with percutaneous drainage. This case report details the rare possibility of a systemic Salmonella infection seeding and destroying a failed kidney graft with subsequent management.
53-year-old Jamaican woman with history of hypertension, diabetes mellitus type 2 and end-stage renal disease presented to an outside hospital in December 2013. The patient was admitted with altered mental status, fevers, abdominal pain, fatigue and anorexia ongoing for two months, but without diarrhea. Her graft history dates to 2007 after receiving a deceased donor kidney transplant but failed after graft rejection and resumed hemodialysis in February 2013. Her remaining immunosuppression at time of presentation was prednisone. After resuscitation, she recovered mental status, but abdominal pain persisted which prompted imaging with an MRI showing a fluid collection and air pockets in the right lower quadrant of the abdomen, abutting the right psoas muscle. The patient was started on vancomycin at that time due to concern for Staphylococcus aureus. CT guided abscess drainage on day 5 of hospitalization retrieved 20mL of purulent material that was sent for gram stain and culturing. Gram stain showed 5-10 WBCs (1+) and rare 1-2 gram positive cocci per slide; however, despite no gram negative rods in the smear, few colonies of Salmonella grew from automated aerobic cultures on proprietary media. The patient was changed to ciprofloxacin 200mg BID IV on approximately day 8th based on Salmonella sensitivities. She was a febrile for the remainder of her hospital course. Final sero typing on day 16 indicated Salmonella enterica subspecies sero type Group O: 47, 48, or 50. Unfortunately due to time and outside laboratory circumstances, H antigen was not performed and it is unclear if the sample was lost in submission to the California health department. Although this polyvalent sera test indicated O antigens from all subgenera, it contained only the several rare forms of Salmonella entericasubspecies enterica associated with human infections. Blood cultures were negative throughout her hospital course. Acid fast bacillus and fungal cultures were also negative. She was then transported to our facility on day 17. Upon transfer, investigation revealed a total WBC count of 10,900/ mcL with an absolute Neutrophil count of 7,300/mcL. Urinalysis was not done since the patient was anuric. CT scan with contrast confirmed abscess in the renal transplant displaying no apparent kidney parenchyma and a 5.9 x 5.5 x 10.0 cm collection (Figure 1).
Figure 1: CT scan coronal view of abdomen showing transplanted kidney with air cavities and ablation of normal parenchyma.
No other collections or sites of infection were identified. Blood cultures and repeated catheter drainage cultures were negative with patient remaining afebrile. We continued her hemodialysis and adjusted ciprofloxacin dose to 400mg IV QD for dosing convenience. The patient retained a cavity approximately 10cc in size that was drained and lavaged with debridement (Figure 2A).
Figure 2A: Abscessogram demonstrating 10cc cavity 2 weeks after discharge.
Surgical resection was discussed but it would be a high risk vascular surgery as opposed to continued drainage with antibiotics. Patient was switched to IV ceftriaxone 2g QDon day 23 for 6 weeks via peripherally inserted central catheterline for easier compliance and sent home on day 25th after drain tube exchanged. Abscessogram approximately 3 months after admission showed an 8cc cavity and drain was removed for a trial period (Figure 2B). The patient has no recorded recurrence of infection for several months.
Figure 2B: An 8cc cavity remaining 3 months after discharge.