Case presentation of urinary tract infection by StenotrophomonaS maltophilia

Stenotrophomonas maltophilia is an emerging aerobic, non-fermentative, gram-negative multidrug-resistant global opportunistic bacillus. S. maltophilia causes a wide range of infections including respiratory tract infections, blood stream infections and, less commonly, biliary tract infections, skin and soft tissue infections, as well as bone and joint infections. It is increasingly being reported to cause urinary tract infections (UTIs). As for the case report, a 87-year-old male patient visited the Biopathology Laboratory of Nikea Primary Healthcare Center, Piraeus, Greece, for routine examination, being referred by the family doctor (GP). Patient history revealed diabetes mellitus type 2, arterial hypertension, hypercholesterolemia, hypertriglyceridemia, hyperuricemia, chronic obstructive pulmonary disease, diagnosed before 30 years prostate cancer Gleasongrade 6, operated before 15 years, followed by hormone therapy and radiation therapy. Patient history also revealed urinary tract stones with 3 episodes of obstructive pyelonephritis during the last 5 years, followed by hospital admissions and administration of intravenous antibiotic treatment. During the hospital admissions, he had a permanent bladder catheter and received special antimicrobial treatment, for various microorganisms detected in his urine samples, such as Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis and Enterococcus faecalis. Urinary incontinence has been a symptom for 15 years, after the prostate cancer surgery. Moreover, during the last 5 years, the patient faced many difficulties in his daily life because of the urinary incontinence. The situation was managed by bladder catheterisation, which further worsened his condition with recurrent UTIs and new episodes of pyelonephritis with subsequent hospitalization. Urinalysis showed proteinuria, intense pyuria, abundance of micro-organisms and abundance of red blood cells. The urine culture grew monomicrobial Stenotrophomonas maltophilia > 10⁵ CFU/ml. The bacterium was identified by the RapID™ REMEL ONE identification system (Thermo Fisher Scientific). Antimicrobial susceptibility testing revealed susceptibility to Trimethoprime/Sulfamethoxazole, Levofloxacin, Ceftriaxone and moderate susceptibility to Ciprofloxacin and Norfloxacin.The patient received treatment with Trimethoprime/Sulfamethoxazole.