Hydrocarbon degrading microflora in a tropical fuel-contaminated aquifer: assessing the feasibility of PAH bioremediation

An aquifer located within a petroleum processing plant in Moin, Costa Rica, suffers hydrocarbon pollution. This study aimed to determine the ability of indigenous microorganisms from this site to degrade polycyclic aromatic hydrocarbons [PAHs] to evaluate the feasibility of an eventual bioremediation process. Aerobic conditions were found in the aquifer, while microbial analyses of the groundwater indicated the presence of important hydrocarbon-degrading populations. Sixteen PAH-degrading strains were isolated with the ability to grow on naphthalene [5 strains], phenanthrene [3], fluorene [6] and pyrene [2]. Most of the identified isolates belonged to the genus Pseudomonas, although, Comamonas, Sphingomonas Stenotrophomonas and Delftia were also found. A mixture of selected strains was evaluated by its performance of PAH degradation in soil-slurry systems, where efficiency of removal was naphthalene > fluorene > phenanthrene > pyrene. This study is an initial approach to evaluate the feasibility of applying a bioremediation process in the contaminated site

A Case of Delftia acidovorans Peritonitis in a Peritoneal Dialysis Patient Managed with Preserving the Dialysis Catheter / 대한신장학회지

Delftia acidovarans is aerobic, nonfermentative Gram-negative rod commonly found in soil and water. Generally it is nonpathogenic but it unusually can cause bacteremia in immunocompromised patients. We present a case of peritonitis due to D. acidovorans in a patient on continuous ambulatory peritoneal dialysis. A 75-year-old woman was admitted with abdominal pain and cloudy peritoneal effluent. She was empirically treated with intraperitoneal (IP) cefazolin and ceftazidime, and then IP ceftazidime and oral ciprofloxacin, but peritonitis did not improve. Seven days after admission, D. acidovorans was identified from the peritoneal effluent, which was sensitive to amikacin, ceftazidime, ciprofloxacin and imipenem. Catheter removal was considered with regard to poor response to adequate antibiotics; however, 4 days after changing to IP imipenem/cilastatin, abdominal pain, the leukocyte count of peritoneal effluent and C-reactive protein decreased. She was treated with imipenem/cilastatin for two weeks and discharged with the dialysis catheter intact.

Delftia acidovorans Isolated from the Drainage in an Immunocompetent Patient with Empyema / 결핵및호흡기질환

Delftia acidovorans is a gram-negative motile rod found ubiquitously in soil and in water. Confirmed isolation from clinical infections is rare, and has been documented mostly in immunocompromised patients or those with indwelling catheters. A 53-year-old man was referred for the evaluation of a huge mass-like lesion found incidentally by chest X-ray. The lesion occupied more than half of the right lung and was diagnosed as a large loculated pleural effusion by CT scan. Bloody pus was drained through a percutaneous catheter, and D. acidovorans, identified by the Vitek GN card and confirmed by amplification of 16S ribosomal RNA and sequencing analysis, was isolated repeatedly from the drained pus. The patient was treated with imipenem/cilastatin to which the organism was sensitive. This is a rare report of chronic empyema associated with D. acidovorans in the respiratory system of an immunocompetent patient.