A rare case of peritonitis due to Brevundimonas vesicularis

Brevundimonas spp. infection in immunocompromised children: Two case reports

Introduction

Brevundimonas spp. are rare and opportunistic pathogens which may cause infections in patients who are immunocompromised or have underlying disease.

Case report

Two cases with a microbiological diagnosis of Brevundimonas aurantiaca and Brevundimonas spp. are presented. Both occurred in immunocompromised patients with post-chemotherapy febrile neutropenia for B-type acute lymphoblastic leukemia and hepatoblastoma. Antibiogram findings showed resistance to quinolones, ceftazidime, and intermediate resistance to cefepime, being susceptible to carbapenems and aminoglycosides. The cases responded favorably to the administration of carbapenem.

Conclusions

The identification of the species and antimicrobial susceptibility profile favor response to infection, denoting the importance of species identification and the performance of an antibiogram to determine the different susceptibility profiles described in the literature on this emerging pathogen.

Quality of dialysis water and dialysate in hemodialysis centers: highlight for occurrence of non-fermenting gram-negative bacilli

AIMS

To evaluate the physicochemical and microbiological quality of dialysis water and dialysate samples from hemodialysis centers.

METHODS AND RESULTS

Samples were fortnightly collected from three hemodialysis centers in Bauru City, Brazil, between July/2017 and June/2018, at the stages of post-reverse osmosis, reuse and dialysate. Analyses included determination of conductivity, fluoride, nitrate and sulfate; test for total coliform bacteria; count of heterotrophic bacteria; count and identification of non-fermenting gram-negative bacilli (NFGNB); drug susceptibility test; biofilm formation capacity, and genetic similarity among some isolated NFGNB. Of the analyzed samples, only 4/72 (5.6%) had conductivity values ≥ 10 mS/cm, 4/216 (1.9%) presented total coliforms, and 1/216 (0.5%) had heterotrophic bacteria count > 100 CFU/mL. NFGNB were isolated from 99/216 (45.8%) samples, and the major identified microorganisms included Herbaspirillum aquaticum/huttiense, Brevundimonas aurantiaca, Cupriavidus metallidurans, Pseudomonas aeruginosa and Ralstonia insidiosa. Isolates of P. aeruginosa and Burkholderia cepacia complex were sensitive to most antimicrobials and, together with isolates of Ralstonia insidiosa and Ralstonia pickettii, showed strong biofilm formation capacity. Some isolates expressed the same electrophoretic profile on pulsed-field gel electrophoresis, indicating persistence of bacterial clones in the systems over time.

CONCLUSIONS

NFGNB were observed in several dialysis water and dialysate samples from all investigated centers, which may represent a risk to the health of patients.

SIGNIFICANCE AND IMPACT OF THE STUDY

Regular inclusion of actions for NFGNB control and monitoring in hemodialysis fluids are suggested for greater safety of the dialytic process.

Brevundimonas vesicularis Peritonitis in a Chronic Peritoneal Dialysis Patient

Gram-negative peritonitis in chronic peritoneal dialysis patients is difficult to treat and may result in catheter loss. Brevundimonas vesicularis is a Gram-negative rod bacterium which rarely causes infections in humans. A 41-year-old male receiving continuous cycling peritoneal dialysis for 5 months developed culture-negative peritonitis. He failed initial empiric treatment with intraperitoneal vancomycin and levofloxacin and thereafter intravenous gentamicin. B. vesicularis resistant to levofloxacin was isolated from the peritoneal fluid 21 days after his initial symptoms. Despite treatment with intravenous ceftriaxone and oral amoxicillin-clavulanate, the infection persisted, which required removal of the peritoneal catheter in order to cure this infection. We describe the features of B. vesicularis infection in our patient and the rarely reported additional cases.