Bacteremia and intramniotic infection due to Burkholderia cenocepacea
Authors: B. Fidalgo, J. Bosch, T. Cobo, L. Ribera, C. Casals, M. Almela
Journal: Clinical Microbiology and Infection (2020)

Burkholderia cenocepacea is a member of the Burkholderia cepacea complex, currently comprising 22 species. It is a Gram-negative bacillus, mobile, non–spore forming, aerobic, a nonfermenter of glucose and positive catalase and oxidase. It is considered an opportunistic pathogen for humans and is one of the main infectious agents in patients with cystic fibrosis. A case of chorioamnionitis due to Burkholderia pseudomallei infection in pregnancy was reported in Australia [[1]Porter M.C. Pennell C.E. Woods P. Dyer J. Merritt A.J. Currie B.J. Case report: chorioamnionitis and premature delivery due to Burkholderia pseudomallei infection in pregnancy.Am J Trop Med Hyg. 2018; 98: 797-799Crossref PubMed Scopus (4) Google Scholar]. We describe a novel case of bacteraemia with intra-amniotic infection by B. cenocepacea in a pregnant woman. The patient was a 46-year-old woman in the 25th week of gestation after in vitro fertilization in Ghana, who came to our hospital for metrorrhagia, intrauterine growth retardation and oligoamnios. A blood analysis and an ultrasound were performed. In the absence of clinical, analytic and ultrasound symptoms of severity, she was discharged home with outpatient follow-up. In the 26th week of pregnancy, the patient returned to our hospital with temperature of 38°C, a new episode of metrorrhagia, hydrorrhea and abdominal pain. With the diagnosis of preterm prelabour rupture of membranes, a prophylactic broad-spectrum antibiotic treatment with intravenous ampicillin and gentamicin and a single dose of oral azithromycin was administered. Four days later, the patient presented a febrile peak of 39°C with persistent cough as the only symptom. The antibiotic therapy was changed to intravenous ampicillin and cefoxitin, and oral azithromycin was added again for 3 days to cover possible atypical pneumonia. The following microbiologic determinations were requested: blood culture, urine culture, sputum culture, QuantiFERON, molecular detection of influenza virus and respiratory syncytial virus as well as serologies for Bordetella pertussis and parvovirus B-19. The patient refused to undergo amniocentesis. The maternal blood culture was positive after 29 hours of incubation in the Bactec FX system. Gram-negative bacilli were observed in Gram stain, and direct blood culture identification by MALDI-TOF MS confirmed the presence of B. cenocepacea. Antibiogram, performed by the disc diffusion method, showed susceptibility to ceftazidime, cotrimoxazole and meropenem. The minimum inhibitory concentration (MIC) of meropenem was determined by the Etest method and was 1.5. A new blood culture performed 2 days later was also positive for B. cenocepacea, so the treatment was changed to intravenous meropenem. In the 27th week of gestation, in the presence of fever (38.2°C), maternal and foetal tachycardia, and onset of uterine contraction, clinical chorioamnionitis was suspected and an amniocentesis performed. An urgent caesarean section was indicated because of late decelerations of foetal heart rate. Cultures of amniotic fluid (in blood culture bottles) and placental swabs (from foetal and maternal faces), in addition to a blood culture and cultures of a pharyngeal and otic swabs of the newborn, were requested. Antibiotic therapy with intravenous ampicillin and ceftazidime was initiated in the neonate because there was a history of maternal sepsis. The cultures of the amniotic fluid and the placental, otic and pharyngeal swabs were positive for B. cenocepacea with an identical antibiogram to the strain isolated in the maternal blood culture. Antibiotic therapy was withdrawn in the newborn at 4 days of age because of blood culture negativity and the absence of clinical-analytical signs suggestive of infection. The newborn, of gestational age of 27 weeks and birth weight of 700 g, manifested conditions related to prematurity (respiratory distress syndrome, anaemia, hyperbilirubinaemia and intraventricular haemorrhage) and was discharged at 66 days of life. B. cepacea complex inhabits different ecosystems as water or soil. In addition to their involvement in respiratory infections in patients with cystic fibrosis [[2]Scoffone V.C. Chiarelli L.R. Trespidi G. Mentasti M. Riccardi G. Buroni S. Burkholderia cenocepacia infections in cystic fibrosis patients: drug resistance and therapeutic approaches.Front Microbiol. 2017; 8: 1592Crossref PubMed Scopus (64) Google Scholar], epidemic outbreaks have been reported in intensive care units and haemodialysis services resulting from contamination of various fluids and disinfectant solutions. Other vulnerable groups are patients with granulomatous or immunosuppressive diseases. However, there are some reported cases of infected patients without any immunosuppression: arthritis [[3]Rodríguez M.S. de la Fuente J. Montero J. Rodríguez M.I. Artritis por Burkholderia cepacia [Arthritis caused by Burkholderia cepacia].Enferm Infecc Microbiol Clin. 2010; 28: 258-259Crossref PubMed Scopus (2) Google Scholar] and a brain abscess [[4]Hobson R. Gould I. Govan J. Burkholderia (Pseudomonas) cepacia as a cause of brain abscesses secondary to chronic suppurative otitis media.Eur J Clin Microbiol Infect Dis. 1995; 14: 908-911Crossref PubMed Scopus (32) Google Scholar] in two men aged 86 and 39 respectively, and a case of spondylitis [[5]Yang B.H. Lee M.S. Lee J.H. Lee H.J. Pyogenic spondylitis in a healthy adult caused by Burkholderia cepacia.Infect Chemother. 2008; 40: 233Crossref Google Scholar] in a 73-year-old women. Because the species comprising B. cepacea complex are a phenotypically similar group, the differentiation by metabolic test is not very specific. Therefore, the use of molecular techniques is the ideal method for species-level identification. However, the high cost and complexity of these methods has led to proposal of the use of MALDI-TOF MS as the technique of choice when identifying clinical isolates. The B. cepacea complex exhibits natural or intrinsic resistance to aminoglycosides because of the presence of enzyme modifiers in addition to the impermeability to these agents. It is often resistant to β-lactam antibiotics by chromosomal or inducible β-lactamases or by alterations in penicillin-binding proteins. The expulsion pumps can generate resistance to fluoroquinolones and may also present natural resistance to colistin. All authors report no conflicts of interest relevant to this letter.