Sphingomonas spp.

Sphingomonas spp. are aerobic, non-fermenting, Gram-negative rod-shaped bacteria belonging to the Sphingomonadaceae family [1]. The genus comprises at least 95 species, including S. paucimobilis, S. mucosissima, S. echinoides, S. trueperi, S. adhaesiva and S. leidyi [1][2].

Of the large number of Sphingomonas bacteria, two species have been classified as pathogenic to humans: S. paucimobilis and S. mucosissima [2][3]. S. paucimobilis, in particular, is associated with a variety of community-acquired or nosocomial infections. Infections often affect immunosuppressed patients. For example, outbreaks S. paucimobilis have occurred among patients in hematology and oncology wards [2]. In one patient with sickle cell anemia, S. mucosissima caused bacteremia [3].

The following are just some of the many diseases caused by S. paucimobilis and S. mucosissima [2][3]:

  • Bacteremia

  • Peritonitis

  • Meningitis

  • Soft tissue infections

  • Urinary tract infections

  • Visceral abscesses

  • Endocarditis

Sphingomonas spp. are environmental bacteria that mainly occur in water and in soil. The pathogen was often also found in water sources and on objects in hospitals, including shower heads, oxygen flow meters, and hemodialysis machines [2][3][4][5].

Relevance of pathogen in transmission in endoscopy

  • Gastroenterology: Low

  • Pulmonology: Low

  • Ear, nose, and throat: Low

  • Urology: Low

Relevance for endoscope surveillance

  • High concern organism

Transmission route

Transmission can occur via direct or indirect contact with contaminated objects. According to the literature, the most common route of transmission is nosocomial. Contaminated catheters, temperature gages on ventilators, injected drugs, and the hands of medical professionals were identified as sources [2][5][6].

S. paucimobilis were also found during hygienic-microbiological inspections of ultrasound gastroscopes [7].

Resistance to antibiotics

S. paucimobilis are resistant to first-generation penicillins and cephalosporins. S. paucimobilis are sensitive to aminoglycosides, carbapenems and combinations of trimethoprim and sulfamethoxazole (TMP/SMX). Depending on the resistance pattern, third-generation cephalosporins as well as fluoroquinolones can be considered for treatment [2].