When is Burkholderia cepacia complex truly eradicated in adults with cystic fibrosis? A 20-year follow up study.

BACKGROUND: Burkholderia cepacia complex (BCC) infection in cystic fibrosis (CF) is associated with increased morbidity and mortality. Current UK guidance recommends segregation of people with CF according to infection status. To date there is no universally agreed consensus on the number of negative samples or time interval since last isolation of BCC for eradication to be deemed successful. METHODS: All cases of new BCC isolation at Manchester Adult Cystic Fibrosis Centre were followed-up between May 2002-May 2022. The number of subsequent positive and negative sputum samples for BCC were recorded, as well as eradication treatment received. Eradication was deemed successful if there were ≥3 negative sputum samples and no further positive sputum samples for the same species and strain ≥12 months until the end of follow-up. RESULTS: Of 46 new BCC isolation, 25 were successfully eradicated and 21 resulted in chronic infection. 5 (16.7%) cases with exclusively negative sputum samples 6-12 months after initial isolation had subsequent samples that were culture-positive for BCC and 3 (10.7%) cases with exclusively negative sputum samples after 12-24 months had subsequent culture-positive samples. Cases where BCC was eradicated had a greater median number of days of eradication treatment (42, IQR 21-63) compared to those in whom BCC isolation resulted in chronic infection (28, IQR 14-42), p = 0.04. CONCLUSIONS: A cautious approach to segregation should be maintained after new isolation of BCC in CF, as some individuals with ≥3 negative samples 12-24 months after initial isolation had subsequent sputum samples culture-positive for BCC.

Identification of Burkholderia cepacia Complex by PCR: A Simple Way.

United States Pharmacopeia (USP) General Chapter <60> for the detection of Burkholderia cepacia complex (Bcc) members in nonsterile products became official in December 2019. This isolation method requires confirmation of the identity of any growth found on Burkholderia cepacia Selective Agar (BCSA) by additional identification tests (refer to the Interpretation section). This article presents a singleplex polymerase chain reaction (PCR) method to rapidly confirm the membership of any microbial grown on BCSA (and other nutrient medium) in the Bcc group. This method is cost effective as it does not require expensive equipment or reagents; therefore, it can be easily adopted in the industry without an important investment. We validated this singleplex PCR Bcc identification method with previously published PCR primers with an expanded panel of 37 clinical and environmental Bcc isolates. The sources and repositories of these Bcc isolates include contaminated health products and medical devices, patients infected with cystic fibrosis, the National Microbiology Laboratory (NML) internal strain bank, and the American Type Culture Collection (ATCC). All 37 isolates that belong to the Bcc tested positive using our confirmatory identification method. Twenty-two negative controls including four isolates belonging to the genus Burkholderia tested negative as expected. Our work indicates that this singleplex PCR is an efficient confirmatory method for Bcc identification, and it can successfully supplement USP <60> for Bcc isolates identification found in pharmaceutical products.

Burkholderia cepacia infection associated with sickle cell disease: An uncommon entity.

Burkholderia, a multidrug-resistant Gram-negative bacteria, is an uncommon cause of infection mostly in immunocompromised patients with a clinical profile very similar to tuberculosis. The most common conditions associated with this organism are cystic fibrosis and chronic granulomatous diseases. Bacteremia with it occurs in patients who are chronically ill and associated with significant morbidity and mortality. We are reporting here a case of perisplenic intra-abdominal abscess caused by Burkholderia cepacia in a patient with sickle cell disease (SCD).

Molecular Research Comparing the Probabilities of Burkholderia Cepacia Bacterium Diagnosis Procedures.

Burkholderia cepacia is found as part of the B. cepacia complex (Bcc), a collection of highly pathogenic organisms. The Bcc is present almost everywhere in nature; however, it is most prevalent in damp settings, plant roots, and soils. Moreover, Bcc is a major source of morbidity and death in patients due to its high intrinsic antibiotic resistance. The present study aims to isolate and identify gram-negative aerobic bacteria from clinical samples derived from a variety of pathological diseases and investigate the bacterium's virulence factors and genes. The current study included 250 specimens collected from patients suffering from diabetic foot ulcers, urine, burn, wound, sputum, and discharge from the eyes. The samples were collected from both sexes with the age range of 1-75 years. The recorded data showed that males had a higher frequency of infection (79.2%) than females (52%). The results revealed that 7.6% of infected females were between 1-15 years old, while 22% of infected males were aged between 31-45 years. In addition, 26.8% of infected patients (both males and females) were aged between 31-45 years.

Rapid detection of Burkholderia cepacia complex carrying the 16S rRNA gene in clinical specimens by recombinase-aided amplification.

The Burkholderia cepacia complex (BCC) is a group of opportunistic pathogens, including Burkholderia cepacia, Burkholderia multivorans, Burkholderia vietnamiensis and Burkholderia ambifaria, which can cause severe respiratory tract infections and lead to high mortality rates among humans. The early diagnosis and effective treatment of BCC infection are therefore crucial. In this study, a novel and rapid recombinase-aided amplification (RAA) assay targeting the 16S rRNA gene was developed for BCC detection. The protocol for this RAA assay could be completed in 10 min at 39°C, with a sensitivity of 10 copies per reaction and no cross-reactivity with other pathogens. To characterize the effectiveness of the RAA assay, we further collected 269 clinical samples from patients with bacterial pneumonia. The sensitivity and specificity of the RAA assay were 100% and 98.5%, respectively. Seven BCC-infected patients were detected using the RAA assay, and three BCC strains were isolated from the 269 clinical samples. Our data showed that the prevalence of BCC infection was 2.60%, which is higher than the 1.40% reported in previous studies, suggesting that high sensitivity is vital to BCC detection. We also screened a patient with B. vietnamiensis infection using the RAA assay in clinic, allowing for appropriate treatment to be initiated rapidly. Together, these data indicate that the RAA assay targeting the 16S rRNA gene can be applied for the early and rapid detection of BCC pathogens in patients with an uncharacterized infection who are immunocompromised or have underlying diseases, thereby providing guidance for effective treatment.

Management of Cepacia syndrome in an immunocompetent non-cystic fibrosis adult patient.

Burkholderia cepacia complex (BCC) is nonfermenting, Gram-negative bacteria known to cause high morbidity and mortality. They commonly affect patients with cystic fibrosis (CF) and are often missed in those without, despite being fatal if left untreated. We report a case of cepacia syndrome in a 42-year-old, immunocompetent man without CF who initially presented with sepsis secondary to pneumonia. Multiple isolates from blood, synovial fluid, and wound swabs grew BCC. Treatment options and management strategies remain poorly understood for BCC in general and in cases without CF in specific. We successfully treated the patient using a combination of intravenous and inhalational antibiotics. This case report elaborates on the disease presentation, investigations, and management strategy employed to treat this rare infection.

Diabetic foot infection caused by bacteria of the Burkholderia cepacia complex: report of an unusual case and a scoping literature review.

Burkholderia cepacia complex (BCC) is group of widespread gram-negative bacillus organized in over 20 phylogenetically distinct bacterial species. According to previous studies, BCC species pathogens are widely reported in patients with cystic fibrosis (CF), but not in individuals with diabetes mellitus (DM). In this case report, a 42-year-old male patient with DM and a foot infection caused by BCC is presented. The patient was hospitalized after antibiotic treatment failure and improved after two surgical debridement procedures and a high-dose extended infusion (EI) of meropenem. The team of vascular surgeons and the infectious disease specialists worked fervently to solve the case. Finally, a scoping review was conducted to map BCC infections in patients with DM.

Burkholderia cepacia Infections at Sites Other than the Respiratory Tract: A Large Case Series from a Tertiary Referral Hospital in Lebanon.

OBJECTIVES: The Burkholderia cepacia complex (Bcc), which was originally thought to be a single species, represents a group of 24 distinct species that are often resistant to multiple antibiotics, and usually known to cause life-threatening pulmonary infections in cystic fibrosis patients. Herein we describe a series of non-respiratory Bcc infections, the risk factors and epidemiologic factors, in addition to the clinical course. PATIENTS AND METHODS: This is a retrospective chart review of 44 patients with documented B. cepacia infections isolated from sites other than the respiratory tract admitted between June 2005 and February 2020 to the American University of Beirut Medical Center (AUBMC), a tertiary referral hospital for Lebanon and the Middle East region. The epidemiological background of these patients, their underlying risk factors, the used antibiotic regimens, and the sensitivities of the B. cepacia specimens were collected. RESULTS: The majority of the Bcc infections (26/44, 59.1%) were hospital-acquired infections. The most common nationality of the patients was Iraqi (18/44, 40.9%), and the most common site of infection was bacteremia (17/44, 38.6%), followed by skin and soft tissues infections (16/44, 36.4%) and vertebral osteomyelitis (8/44, 18.2%). Most of the isolated B. cepacia were susceptible to ceftazidime, carbapenems, followed by TMP-SMX. Patients responded well to therapy with good overall outcome. CONCLUSIONS: Bcc can cause infections outside the respiratory tract, mostly as hospital-acquired infections and in immunocompromised patients. Most patients were referred from countries inflicted by wars raising the possibility of a potential role of conflicts which need to be investigated in future studies. Directed therapy according to susceptibility results proved effective in most patients.

Evaluating the alginate oligosaccharide (OligoG) as a therapy for Burkholderia cepacia complex cystic fibrosis lung infection.

OligoG has previously shown potentiation of aztreonam against Burkholderia cepacia complex (Bcc) through biofilm disruption. A randomized, double-blind, placebo-controlled cross-over design was used to evaluate safety and efficacy of inhaled OligoG as a therapy for Bcc-infected CF patients taking aztreonam. Subjects received OligoG (1050 mg daily) or matching placebo for 28-days. Of 14 subjects completing the study, 8 showed a mean decrease in total bacterial CFU's (0.82 log10) after OligoG treatment. There was a reduction in mean Bcc CFU's (2.19 log10) after OligoG treatment but this was not statistically significant. Rheology analysis showed improvements in phase-angle after OligoG, but there was no statistically significant improvement in lung function parameters. Six out of 12 QoL summary scores showed relative improvement after OligoG treatment compared to placebo. There was a favourable safety profile for OligoG. Potential for reducing Bcc warrants further investigation of OligoG for the treatment of infection in CF.

Burkholderia cepacia complex bacteremia outbreaks among non-cystic fibrosis patients in the pediatric unit of a university hospital.

BACKGROUND: Burkholderia cepacia complex (Bcc) comprises multi-drug resistant, Gram-negative, motile, and aerobic bacteria. Bcc causes severe nosocomial infections particularly in patients with intravascular catheters and in those with cystic fibrosis. We studied a Bcc outbreak in non-cystic fibrosis patients. METHODS: We analyzed data from six patients hospitalized at our center. Blood cultures identified as infectious were incubated onto 5% blood sheep agar, chocolate agar, and eosin methylene blue (EMB) agar. We examined possible sites that could be sources of infection at the clinic. We confirmed isolations with pulsed-field gel electrophoresis (PFGE) tests. RESULTS: The first patient was hospitalized due to left renal agenesis, urinary tract infection, and renal failure. Bcc was isolated in blood cultures obtained due to high fever on the third day of hospitalization. We stopped new patient hospitalizations after detecting Bcc in blood cultures of other five patients. We did not detect further positive specimens obtained from other clinic and the patient rooms. PFGE patterns were similar in all clinical isolates of Bcc indicating that the outbreak had originated from the source. CONCLUSIONS: Bcc infection should be considered in cases of nosocomial outbreaks of multi-drug resistant organisms that require hospitalization at intensive care units. Control measures should be taken for prevention of nosocomial infections and required investigations should be done to detect the source of infection.

SARS-CoV-2 and Burkholderia cenocepacia infection in a patient with Cystic Fibrosis: An unfavourable conjunction?

The effects of the concomitant infection by COVID-19 and Burkholderia cepacia (Bc) in CF are not known. We describe the case of a 34 years woman with CF, colonized by Bc and found SARS-CoV2 positive. In the first hospital week she suffered acute respiratory failure and chest imaging showed interstitial involvement and multiple thickenings. She was treated with antibiotics, dexamethasone, remdesivir and heparin, with gradual improvement and discharge at day 20th. The reciprocal role of SARS-CoV-2 and Bc, their potential interactions and the contribution of the individual therapies to the favourable outcome are unclear. It is debatable whether it was SARS-CoV2 that triggered a Bc pulmonary exacerbation or if the chronic Bc infection facilitated the development of a COVID-19 more aggressive than usually seen in CF. If the latter hypothesis were confirmed by similar cases, Bc colonization should be regarded as a risk factor for severe COVID-19 expression in CF.

A Phylogeny-Informed Proteomics Approach for Species Identification within the Burkholderia cepacia Complex.

Ancestral genetic exchange between members of many important bacterial pathogen groups has resulted in phylogenetic relationships better described as networks than as bifurcating trees. In certain cases, these reticulated phylogenies have resulted in phenotypic and molecular overlap that challenges the construction of practical approaches for species identification in the clinical microbiology laboratory. Burkholderia cepacia complex (Bcc), a betaproteobacteria species group responsible for significant morbidity in persons with cystic fibrosis and chronic granulomatous disease, represents one such group where network-structured phylogeny has hampered the development of diagnostic methods for species-level discrimination. Here, we present a phylogeny-informed proteomics approach to facilitate diagnostic classification of pathogen groups with reticulated phylogenies, using Bcc as an example. Starting with a set of more than 800 Bcc and Burkholderia gladioli whole-genome assemblies, we constructed phylogenies with explicit representation of inferred interspecies recombination. Sixteen highly discriminatory peptides were chosen to distinguish B. cepacia, Burkholderia cenocepacia, Burkholderia multivorans, and B. gladioli and multiplexed into a single, rapid liquid chromatography-tandem mass spectrometry multiple reaction monitoring (LC-MS/MS MRM) assay. Testing of a blinded set of isolates containing these four Burkholderia species demonstrated 50/50 correct automatic negative calls (100% accuracy with a 95% confidence interval [CI] of 92.9 to 100%), and 70/70 correct automatic species-level positive identifications (100% accuracy with 95% CI 94.9 to 100%) after accounting for a single initial incorrect identification due to a preanalytic error, correctly identified on retesting. The approach to analysis described here is applicable to other pathogen groups for which development of diagnostic classification methods is complicated by interspecies recombination.

Parotitis due to Burkholderia cepacia infection after autologous hematopoietic stem cell transplantation.

Burkholderia cepacia predominantly causes opportunistic infections in hospitalized and immunocompromised patients such as patients with cystic fibrosis, cancer, or human immunodeficiency virus (HIV). Nonetheless, Burkholderia cepacia is infrequently reported to cause infection in hematopoietic stem cell transplantation (HSCT) recipients. Herein, we report a rare case of suppurative parotitis in a 31-year-old patient with T-cell lymphoblastic lymphoma (T-LBL) who underwent auto-HSCT. The secretion from the Stensen duct was collected, and Burkholderia cepacia was detected using the VITEK-2 identification system. Additionally, sensitive antibiotic therapy against this bacterium was also effective. This is the first case of parotitis triggered by Burkholderia cepacia after auto-HSCT, and it is also the first reported domestic case. This case emphasizes the importance of considering bacterial infections in general and Burkholderia cepacia specifically in HSCT patients with post-transplant parotitis.

Is prolonged incubation required for optimal recovery of Burkholderia cepacia complex in sputum from cystic fibrosis patients? Data versus dogma.

Cystic fibrosis (CF) expert groups globally recommend using selective medium for isolation of Burkholderia cepacia complex (BCC) from respiratory specimens of CF patients. However, there is no consensus available for optimal duration of incubation and recommendations are variable. The purpose of our study was to compare the difference in recovery of BCC in CF samples at 48 hours versus 7 days when inoculated on Burkholderia cepacia selective agar. A total of 307 consecutive clinical respiratory specimens from our local CF unit were studied prospectively (August 2017 to December 2017). All specimens were inoculated on Burkholderia cepacia medium, containing polymyxin B, gentamicin and ticarcillin. In our laboratory, these plates are routinely incubated for 48 hours as per the manufacturer's recommendation. However, for this study all plates with no growth at 48 hours were further incubated for total of 7 days at 35°C in O2. Plates were read daily to look for any growth. Microbial identification was performed using MALDI-TOF Vitek MS (database V3.0). Of the 307 CF respiratory specimens cultured, 177 (58%) were from paediatric and 130 (42%) were from adult patients; 155 (50%) specimens were sputum, 148 (48%) were cough swabs and four (1%) were bronchoalveolar lavage (BAL). All specimens from adults were sputum except one BAL. Thirteen (4%) cultures from eight adult and five paediatric specimens grew BCC. The majority (294, 96%) of specimens had no growth when incubated for 7 days. All 13 positive isolates recovered within 48 hours and there were no additional positive isolates found beyond 48 hours of incubation. We conclude from our analysis that prolonged incubation is not warranted for recovery of BCC in CF specimens if selective medium containing gentamicin and polymyxin is used. By adopting this approach of non-extended incubation, the burden of work on laboratory personnel can be significantly reduced and much faster turnaround time for CF cultures achieved. Our study confirms the results of recently published data on this point and challenges the prevailing dogma of utility of extended incubation for BCC isolation. For devising consensus statements for microbiology laboratories on this issue, CF societies and expert groups should consider reviewing data from the recent studies.

Diffuse lamellar keratitis associated with tabletop autoclave biofilms: case series and review.

PURPOSE: To report a diffuse lamellar keratitis (DLK) cluster attributed to autoclave reservoir biofilm and to review the risk and prevention of DLK and toxic anterior segment syndrome (TASS) caused by such biofilms. SETTING: Refractive Surgery Center, University of California, Berkeley. DESIGN: Observational case-control study and review of literature. METHODS: Eyes were evaluated for DLK following laser in situ keratomileusis (LASIK) over a 5-year period. Multiple changes in surgical and operating room protocols were prompted by a cluster of DLK cases. The autoclave reservoir chamber wall was cultured for microbial contamination. The MEDLINE database was used to identify relevant past publications. RESULTS: From January 7, 2010, to December 18, 2014, 1115 eyes received LASIK. Between September 2, 2010, and June 11, 2012, 147 eyes of 395 LASIK cases developed DLK (37.2%). Systematic modifications in surgical protocols were unsuccessful in ending the prolonged cluster of DLK cases until the STATIM 2000 autoclave was replaced with a new STATIM autoclave and a reservoir sterilization and surveillance protocol implemented. Over the subsequent 30 months, DLK incidence was reduced to 2.2% (14 DLK cases from 632 total LASIK cases, P < .0001). The retired autoclave reservoir chamber wall cultures grew Pseudomonas aeruginosa and the Burkholderia cepacia complex. CONCLUSIONS: Fluid reservoirs of tabletop steam autoclaves can readily develop polymicrobial biofilms harboring microbial pathogens, whose inert molecular byproducts can cause DLK and TASS when introduced to the eye by surgical instruments. Stringent reservoir cleaning and maintenance may significantly reduce this risk by preventing and removing these biofilms.

Burkholderia Cepacia Complex Causing Pneumonia in an Immunocompetent Non-Cystic Fibrosis Patient: Case Report and Review of Literature.

BACKGROUND: Burkholderia cepacia complex is widespread in the environment and has been recognized as a cause of opportunistic pulmonary infections, particularly in patients with Cystic Fibrosis (CF). The natural ecology of the bacteria as part of plant growth-promoting rhizosphere provides stark contrast to its infectious potential. Its preponderance as a nosocomial pathogen may be due to its ability to survive in antiseptic solutions, contaminate equipments and intrinsic antimicrobial resistance. CASE: An elderly, diabetic male was evaluated for hemoptysis, fever and cough. Chest computed tomography showed a thick walled cavity in the left lung and hilar lymphadenopathy. Sputum examination showed Gram negative bacilli and no acid fast bacilli. Sputum culture yielded growth of non-fermentative Gram negative bacilli on two occasions, but blood culture was sterile. The isolate was identified as B. cepacia by Matrix Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS). The patient's general condition remained poor and in spite of initiation of antibiotics, the patient expired after an episode of massive hemoptysis. CONCLUSION: This report raises concerns regarding the spread and severity of B. cepacia infection in non-compromised patients in the community and the need to suspect and identify it. Since the organism is inherently resistant to antipseudomonal penicillins, aminoglycosides and polymyxin B, differentiation from Pseudomonas spp. and determining antimicrobial susceptibility is paramount for treatment.

Accurate identification and epidemiological characterization of Burkholderia cepacia complex: an update.

Bacteria belonging to the Burkholderia cepacia complex (Bcc) are among the most important pathogens isolated from cystic fibrosis (CF) patients and in hospital acquired infections (HAI). Accurate identification of Bcc is questionable by conventional biochemical methods. Clonal typing of Burkholderia is also limited due to the problem with identification. Phenotypic identification methods such as VITEK2, protein signature identification methods like VITEK MS, Bruker Biotyper, and molecular targets such as 16S rRNA, recA, hisA and rpsU were reported with varying level of discrimination to identify Bcc. rpsU and/or 16S rRNA sequencing, VITEK2, VITEK MS and Bruker Biotyper could discriminate between Burkholderia spp. and non-Burkholderia spp. Whereas, Bcc complex level identification can be given by VITEK MS, Bruker Biotyper, and 16S rRNA/rpsU/recA/hisA sequencing. For species level identification within Bcc hisA or recA sequencing are reliable. Identification of Bcc is indispensable in CF patients and HAI to ensure appropriate antimicrobial therapy.

Decontamination and Lung Transplantation of a Patient With Cystic Fibrosis With Resistant Infections.

We describe the use of a decontamination protocol that allowed for successful lung transplantation in a patient with cystic fibrosis with necrotizing pneumonia from highly antibiotic-resistant pathogens (Burkholderia and Psuedomonas species). This strategy may allow for successful lung transplantation in patients with cystic fibrosis with multidrug-resistant infections previously considered nontransplantable.