Sphingomonas paucimobilis Bacteremia in a Hemodialysis Patient and Literature Review

Gursoy et al. Int J Crit Care Emerg Med 2018, 4:041 Citation: Gursoy S, Yasar KK, Sari ND, Kuvat N, Ozturk S (2018) Sphingomonas Paucimobilis Bacteremia in a Hemodialysis Patient and Literature Review. Int J Crit Care Emerg Med 4:041. doi.org/10.23937/24743674/1510041 Accepted: August 09, 2018: Published: August 11, 2018 Copyright: © 2018 Gursoy S, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.


Introduction
Sphingomonas paucimobilis is an aerobic, gram-negative, yellow-pigmented, non-fermentative, motile bacterium normally found in soil and freshwater which rarely causes serious life-threatening infections.These bacteria have been recently reported to cause community-acquired or healthcare-associated infections.This paper has aimed to draw attention to the fact that this agent may be found in hemodialysis patients even though it is rare by presenting a case of Sphingomonas paucimobilis bacteremia who have been receiving hemodialysis for 20 years.

Summary
Sphingomonas paucimobilis is an aerobic, non-fermentative gram-negative motile bacterium that may be an unusual infectious agent for immunocompromised host.Intravascular instrumentations are commonly applied in the hemodialysis patients.These procedures have an increased risk for infection with unusual, rare and opportunistic pathogens.Sphingomonas paucimobilis has been recently reported to cause community-acquired or healthcare-associated infections.A case of bacteremia associated with hemodialysis catheter caused by this bacterium that rarely leads to hospital infections has been represented.
patients.Invasive procedures commonly performed during dialysis applications increase either predisposition to infections and incidence of rare infectious agents in these end-stage renal patients.Sphingomonas paucimobilis has been isolated first at 1977 as Pseudomonas paucimobilis and then classified currently as Sphingomonas paucimobilis (Group IIK, biotype 1) phylogenetically depending on its specific sphingolipid structure by Yabuuchi, et al. 1990 [1].It is a non-fermentative, catalase and oxidase positive, Gram negative and very low motile bacillus with one single flagellum.Endotoxin-lipid A fraction of this bacterium has a sphingolipid-structure that stimulates mononuclear cells 105 times less than lipid A and causes secretion of TNF-α, interleukin-1 and interleukin-6.That explains the indistinct clinical symptoms [2].S. paucimobilis infections are not had high mortality rates except of serious infections such as meningitis, septic shock syndrome or ventilator-associated pneumonia.These infections may be community-acquired or healthcare-associated.It has been shown that this agent could be found in also healthy people beside patients with immunosuppression, malignity and diabetes [3,4].In Table 1, most of S. paucimobilis infections in the literature are summarized [3][4][5][6][7][8][9][10][11][12][13][14].
These gram-negative bacilli were identified Sphingomonas paucimobilis using VİTEK2 (Bio Merieux, France) automated identification system and were found resistant to ampicillin sulbactam, ticarcillin, piperacillin, piperacillin-tazobactam, meropenem, gentamicin, tobramycin and colistine; and sensitive to cefepime, tigecycline, trimethoprim-sulfamethoxazole and ciprofloxacin and moderately-sensitive to cefoperazone-sulbactam according to MIC results using the same system.First, the patient was initiated oral ciprofloxacin treatment as an ambulatory outpatient.However, then she was hospitalized and initiated IV ciprofloxacin 2 × 200 mg due to Sphingomonas paucimobilis growth in the repeated blood cultures at the 5 th day of oral treatment.After her fever decreased and general condition improved at the 3 rd day of hospitalization, the IV treatment was completed to 14 days and she was discharged.

Discussion
Infections are major mortality factors in the hemodialysis patients and these patients are always difficult problems that need to be solved in emergency departments.Many pathologies of lymphocyte and granulocyte function associated with uremia occur in these clinical forms were bacteremia and peritonitis and there were 52 separate instances that the agent was isolated [3].The infection sources for S. paucimobilis according to reported articles up to 2014 were summarized in Table 2.Many cases of S. paucimobilis bacteremia and peritonitis are resulted from contaminated solutions including distilled water, hemodialysis fluid and sterile drug solutions.Another review article from Taiwan evaluating totally 42 cases of S. paucimobilis bacteremia has shown that the malignity (57%), immunosuppression (41%), diabetes mellitus (12%) and end-stage renal disease (7%) were the most frequent co-morbid diseases [5].In the same review, the researchers pointed out the high indwelling intravenous device rate of the cases (60%).Our case was also has been receiving hemodialysis for 20 years due to end-stage renal disease.In the literature, S. paucimobilis concomitance with Staphylococcus epidermidis has been reported in only one case [15].Also in our patient, co-infection of CNS and S. paucimobilis may be considered.Actually, partially-improvement despite the proper therapy with vancomycin during the first bacteremia caused by CNS, could be related with dual bacteremia with CNS and S. paucimobilis before the hospitalization.Inability for The agent has been isolated from a wide variety of clinical specimens including blood, urine, dialysate, pus, sputum, wound, sinovial and cerebrospinal fluid.Bacteremia/sepsis, ventilator-associated pneumonia, myositis, peritonitis, postoperative endophthalmitis, arthritis and surgical site infections have been reported.A meta-analysis evaluating S. paucimobilis infections between 1979 and 2010 years revealed that the most frequent S. paucimobilis is generally sensitive to tetracycline, co-trimoxazole, quinolones, and carbapenem.Its sensitivity to third generation cephalosporins and aminoglycosides is variable.In our case, the isolated agent was sensitive to only cefepime, cotrimoxazole, tigecycline and ciprofloxacin.Therapeutic failure to oral quinolone may be associated with lower bioavailability of drug or irregular oral therapy.
Consequently, intravascular instrumentations are commonly applied in the hemodialysis patients, development of immune response may be insufficient due to end-stage renal disease.These factors result in increased risk for infection with unusual, rare and opportunistic pathogens.S. paucimobilis should be kept in mind as a probable agent in dialysis patients with catheter-associated infection who experienced therapeutic failure.

Table 1 :
Most of S. paucimobilis infections in the literature.

Table 2 :
The infection sources for S. paucimobilis according to reported articles up to now.