P. stuartii is an increasingly common bacterium found in the urine of nursing home residents with indwelling Foley catheters . In a 12-year study from a large community hospital in Ohio, P. stuartii was found to cause bacteremia in 49 patients . Of these, 78 % were over 70 years of age, 96 % were admitted to the hospital from a nursing home, and 92 % had a long-term indwelling Foley catheter when admitted to the hospital. Our patient was over 70 years old and lived in a nursing home but did not use an indwelling Foley catheter as he had end-stage renal disease.
We could only find two cases of ocular infection due to P. stuartii in the published literature. Both instances were cases of keratitis rather than conjunctivitis, and neither provided detailed information on the individual P. stuartii infection. Sun et al. described P. stuartii keratitis in the right eye of a 13-year-old girl who had worn an orthokeratology lens for 2 years and presented with a corneal ulcer . The textbook, Smolin and Thoft’s The Cornea: Scientific Foundations and Clinical Practice, provides an original chart of gram-negative bacterial isolates from keratitis from Pittsburgh, PA . They found one case of keratitis from P. stuartii that was not susceptible to any of the tested antibiotics.
Koreishi et al. described five ocular infections from a related bacterium, Providencia rettgeri . They detailed two cases of keratitis, one of dacryocystitis, one of conjunctivitis, and one of conjunctivitis/endophthalmitis. All five of their subjects were elderly. Three of their subjects were either locally or systemically immunocompromised (one of their subjects had diabetes and used topical steroids, a second used topical steroids, and a third was being treated with methotrexate). Two of their patients had positive urinary analyses (leukocytosis in one and bacteria in the other), but neither was cultured. They found that concurrent urinary tract infections and an immunocompromised state were likely risk factors.
Similar to other patients infected with P. Stuartii, our patient was an elderly man living in a nursing home who was likely immunocompromised from diabetes mellitus. We could not confirm if his urinary tract was infected with P. stuartii as he produced no urine that could be cultured. Our patient’s conjunctivitis was successfully treated with vancomycin drops, oral sulfamethoxazole and trimethoprim, and oral moxifloxacin hydrochloride. We found that conjunctival swab cultures were instrumental in identifying the infecting bacteria and its antibiotic susceptibility.
In summary, P. stuartii is an uncommon cause of ocular infections, but may be suspected in elderly, immunocompromised nursing home residents.