Ralstonia picketti neonatal sepsis: a case report

Molecular epidemiological and clinical infection characteristics analysis of Ralstonia

PURPOSE

This study was to clarify the molecular epidemiology and clinical infection characteristics of Ralstonia pickettii and establish sequence typing system.

METHODS

48 nonrepetitive Ralstonia pickettii strains were collected from January 2008 to December 2013 at the Chinese People's Liberation Army General Hospital (PLAGH) and were identified through a specific PCR experiment, 16 S rDNA experiment and VITEK 2 system to compare the identification accuracy. The sequence types of the strains were analyzed by multilocus sequence typing (MLST) method. The antibiotic sensitivity of these strains was determined with disc diffusion tests and broth microdilution method. The clinical data of Ralstonia pickettii infected patients were collected.

RESULTS

All of the 48 strains were identified as Ralstonia pickettii by VITEK 2 system. 30 and 34 strains were identified as Ralstonia pickettii by PCR and 16 S rDNA experiment respectively. ST9 was the most sequence types (STs) in these 18 STs of 42 strains. 42 strains were divided into 2 groups (A and B) and 18 genotypes. Ralstonia pickettii was sensitive to some cephalosporins, β-lactam/β-lactamase inhibitor, levofloxacin and trimethoprim/sulfamethoxazole. Cough, sputum, shortness of breath and pulmonary rales were the common clinical symptoms of most Ralstonia pickettii infected patients.

CONCLUSION

We established a sequence typing system with a relatively fine resolution and the PCR assay is a faster and more sensitive method for clinical identification of Ralstonia pickettii. ST9 is the most common sequence types of Ralstonia pickettii. The most common clinical characteristics of Ralstonia pickettii infected patients were cough, sputum, shortness of breath and pulmonary rales.

Ralstoniapickettii bloodstream infection in the patient with Guillain-Barre syndrome under plasmapheresis

Ralstonia pickettii is a rare Gram-negative opportunistic bacterium that causes rare infections such as bacteremia, neonatal sepsis, endocarditis, and meningitis in hospitalized or immunocompromised patients. In this study, we identified and reported bloodstream infection caused by R. pickettii in a 15 -year-old boy patient with an autoimmune disease, Guillain-Barré syndrome, under plasmapheresis and intravenous immune globulin (IVIG) therapy. He was referred for admission to the neurology center of the teaching hospital of Shiraz, Iran for inability to walk, and lower extremity muscle weakness. After he was treated with plasmapheresis once during hospitalization, and after severe fever besides shivering blood cultures using BACT/ALERT®3D instrument were positive for R. pickettii.According to antibiotic susceptibility test reports, Ciprofloxacin (5 μg) was prescribed. Fortunately, after starting antibiotic treatment, blood culture results reported no growth after 5 days. Indeed, the patient was infected with nosocomial hepatitis A and URSOBIL (300 mg/BID/Po) was administered. Hence, after reporting the infection occurrence to the hospital infection control unit, initial and possible measures such as device infection control, replacement of potentially polluted plasmapheresis fluids, disinfecting the environment and replacing old sterile washing water with new sources were carried out in plasmapheresis unit. In conclusion, R. pickettii is a rare nosocomial infection that is responsible for the contamination of medical equipment, especially in hemodialysis, plasmapheresis devices and sterile solutions. Also, it is suggested that the role and importance of rare environmental bacteria as the causative agents of human infections should not be ignored in medical centers.

A case of meningitis caused by Ralstonia insidiosa, a rare opportunistic pathogen

BACKGROUND

Ralstonia is a genus of Gram-negative opportunistic bacteria that can survive in many kinds of solutions and cause a variety of infections. Ralstonia spp. have increasingly been isolated and reported to cause infections in recent years, thanks to the development of identification methods such as matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and gene sequencing. However, infections caused by Ralstonia insidiosa are still rare. Only a few cases of respiratory infections and bloodstream infections have been reported, none of which involved meningitis. To the best of our knowledge, this is the first reported case of meningitis caused by R. insidiosa worldwide. It is necessary to report and review this case.

CASE PRESENTATION

We report a case of meningitis caused by R. insidiosa following lumbar surgery in China. The patient exhibited symptoms of headache, dizziness, and recurrent fever. The fever remained unresolved after empiric antibiotic therapy with intravenous cefotaxime and vancomycin in the initial days. Cerebrospinal fluid (CSF) culture yielded Gram-negative non-fermentative bacteria, which were identified as R. insidiosa. As there was a lack of antibiotic susceptibility testing results, clinical pharmacists conducted a literature review to select appropriate antibiotics. The patient's condition improved after receiving effective treatment with intravenous cefepime and levofloxacin.

CONCLUSIONS

Uncommon pathogens, such as R. insidiosa, should be considered in postoperative central nervous system (CNS) infections, particularly in cases with unsatisfactory results of empiric anti-infective therapy. This is the first reported case of meningitis caused by R. insidiosa worldwide. MALDI-TOF MS provides rapid and accurate identification of this pathogen. The antibiotic susceptibility testing results of R. indiosa may be interpreted based on the breakpoints for Pseudomonas spp., Burkholderia cepacia spp., and Acinetobacter spp. Our case presents a potential option for empiric therapy against this pathogen, at least in the local area. This is crucial to minimize the severity and mortality rates associated with meningitis. Standardized antibiotic susceptibility testing and breakpoints for the Ralstonia genus should be established in the future as cases accumulate. Cefepime and levofloxacin may be potential antibiotics for infections caused by R. indiosa.

Children with infectious pneumonia caused by Ralstonia insidiosa: A case report

BACKGROUND

Ralstonia is a Gram-negative non-fermentative bacterium widespread in nature, and includes four species, Ralstonia pickettii, Ralstonia solanacearum, Ralstonia mannitolilytica, and Ralstonia insidiosa, which were proposed in 2003. Ralstonia is mainly found in the external water environment, including municipal and medical water purification systems. This bacterium has low toxicity and is a conditional pathogen. It has been reported in recent years that infections due to Ralstonia are increasing. Previous studies have shown that most cases of infection are caused by Ralstonia pickettii, a few by Ralstonia mannitolilytica, and infections caused by Ralstonia insidiosa are rare.

CASE SUMMARY

A 2-year-old Chinese child suffered from intermittent fever and cough for 20 d and was admitted to hospital with bronchial pneumonia. Bronchoscopy and alveolar lavage fluid culture confirmed Ralstonia insidiosa pneumonia. The infection was well controlled after treatment with meropenem and azithromycin.

CONCLUSION

Ralstonia infections are increasing, and we report a rare case of Ralstonia insidiosa infection in a child. Clinicians should be vigilant about Ralstonia infections.

The genus Ralstonia: The new kid on the block

The genus Ralstonia comprises of aerobic, gram-negative, oxidase positive, nonfermentative, largely environmental organisms. They are an emerging pathogen in the hospital setting and are increasingly associated with opportunistic infections and outbreaks. We hereby present a case series of six patients diagnosed with bacteraemia caused by Ralstonia spp. and a brief review of literature. These cases highlight that isolation of a nonfermenting gram-negative bacillus from blood culture of a patient admitted in critical care setting should not be ignored as mere contaminant. Clinicians and microbiologists need to work as a team to combat this novel bug.

Elevated neutrophil - to - monocyte ratio as a prognostic marker for poor outcomes in neonatal sepsis

Objectives

Neonatal sepsis is one of the leading causes of neonatal death. The aim of this study was to evaluate the value of neutrophil - to - monocyte ratio (NMR) in predicting mortality in neonatal sepsis.

Methods

In this present retrospective study, a total of 134 neonates with sepsis were included. Baseline laboratory parameters were collected. The best cutoff value of NMR was determined by receiver operating characteristic (ROC) curve. Univariate and multivariate analysis were carried out to survey the predict value of NMR.

Results

The results showed that NMR in non-survival group was significantly higher than that in survival group. Results from multivariate analysis showed that high NMR was an independent risk factor for neonatal sepsis (Hazard ratio (HR): 7.519, p = 0.001). ROC displayed that the area under curve (AUC) of NMR was 0.740, sensitivity and specificity of NMR were 80% and 65.8% when 7.65 was selected.

Conclusions

NMR could be a promising prognostic factor for neonatal sepsis.

Ralstonia Mannitolilytica, an Unusual Pathogen in the Neonatal Intensive Care Unit: A Case of Neonatal Sepsis and Literature Review

BACKGROUND

Premature infants are considered high-risk subgroup for neonatal sepsis due to yet defective immune system, interventions practised and synergy of factors favoring multiple resistance of Gram-positive and Gram-negative pathogens to antimicrobial agents.

CASE PRESENTATION

We present a case of late-onset neonatal sepsis in a premature infant caused by an uncommon pathogen; a premature infant of extremely low birth weight had in his 4th week of life severe clinical deterioration with lethargy, fever, pallor, mottling, abdominal distention, tachycardia, and worsening respiratory impairment. Full septic screen was performed, broad-spectrum antibiotic therapy was initiated and supportive care per needs was provided. Blood cultures (endotracheal tube tip cultures) isolated meropenem- and gentamicin-resistant strain of rare pathogen Ralstonia mannitolilytica. Ralstonia spp. are aerobic, Gram-negative, lactose non-fermenting, oxidaseand catalase-positive bacilli, thriving in water and soil. Ralstonia spp. are identified only sporadically as causative agents of neonatal sepsis; to our knowledge, this is the second report of neonatal sepsis due to R. mannitolilytica in the literature so far. Our patient was eventually treated (per sensitivity pattern) with intravenous ciprofloxacin and recovered well from the infection.

CONCLUSION

We intend to raise awareness among neonatologists with regard to early detection of unusual pathogens, the emergence of antibiotic resistance patterns, and the obligation for adherence to infection control policies.

Identification and Elimination of the Clinically Relevant Multi-Resistant Environmental Bacteria Ralstonia insidiosa in Primary Cell Culture

In times of spreading multidrug-resistant bacteria, species identification and decontamination of cell cultures can be challenging. Here, we describe a mobile cell culture contaminant with “black dot”-like microscopic appearance in newly established irreplaceable hybridoma cell lines and its identification. Using 16S rRNA gene sequencing, species-specific PCRs, whole genome sequencing (WGS), and MALDI-TOF mass spectrometry, the contaminant was identified as the ubiquitous environmental and clinically relevant Gram-negative bacterium Ralstonia insidiosa (R. insidiosa), a strong biofilm producer. Further characterizations by transmission electron microscopy (TEM) and biochemical API test were not conclusive. Whole genome sequencing of our R. insidiosa isolate revealed numerous drug-resistance determinants. Genome-wide comparison to other Ralstonia species could not unambiguously designate our isolate to R. insidiosa (<95% average nucleotide identity) suggesting a potential novel species or subspecies, closely related to R. insidiosa and R. pickettii. After determining the antibiotic susceptibility profile, the hybridoma cell culture was successfully decontaminated with ciprofloxacin without affecting antibody production.

Characterization of a Unique Bordetella bronchiseptica vB_BbrP_BB8 Bacteriophage and Its Application as an Antibacterial Agent

Bordetella bronchiseptica, an emerging zoonotic pathogen, infects a broad range of mammalian hosts. B. bronchiseptica-associated atrophic rhinitis incurs substantial losses to the pig breeding industry. The true burden of human disease caused by B. bronchiseptica is unknown, but it has been postulated that some hypervirulent B. bronchiseptica isolates may be responsible for undiagnosed respiratory infections in humans. B. bronchiseptica was shown to acquire antibiotic resistance genes from other bacterial genera, especially Escherichia coli. Here, we present a new B. bronchiseptica lytic bacteriophage—vB_BbrP_BB8—of the Podoviridae family, which offers a safe alternative to antibiotic treatment of B. bronchiseptica infections. We explored the phage at the level of genome, physiology, morphology, and infection kinetics. Its therapeutic potential was investigated in biofilms and in an in vivoGalleria mellonella model, both of which mimic the natural environment of infection. The BB8 is a unique phage with a genome structure resembling that of T7-like phages. Its latent period is 75 ± 5 min and its burst size is 88 ± 10 phages. The BB8 infection causes complete lysis of B. bronchiseptica cultures irrespective of the MOI used. The phage efficiently removes bacterial biofilm and prevents the lethality induced by B. bronchiseptica in G. mellonella honeycomb moth larvae.

A case of persistent bacteraemia by Ralstonia mannitolilytica and Ralstonia pickettii in an intensive care unit

The Ralstonia spp. genus is a group of non-fermentative, Gram-negative bacteria often resistant to many antibiotics, which are emerging as opportunistic pathogens frequently associated with infections in hospital settings. We present herein a case of combined R. pickettii and R. mannitolilytica persisting and relapsing bacteraemia, possibly caused by a septic arterial thrombosis secondary to the rupture of an internal carotid artery aneurysm. Microbiology studies showed that both Ralstonia isolates produced biofilm and carried class D oxacillinase genes. When confronted with infections caused by members of the Ralstonia genus, identification to the species level is crucial for correct clinical management, as the two species show different antibiotic susceptibility patterns.

Golden hour of neonatal life: Need of the hour

"Golden Hour" of neonatal life is defined as the first hour of post-natal life in both preterm and term neonates. This concept in neonatology has been adopted from adult trauma where the initial first hour of trauma management is considered as golden hour. The "Golden hour" concept includes practicing all the evidence based intervention for term and preterm neonates, in the initial sixty minutes of postnatal life for better long-term outcome. Although the current evidence supports the concept of golden hour in preterm and still there is no evidence seeking the benefit of golden hour approach in term neonates, but neonatologist around the globe feel the importance of golden hour concept equally in both preterm and term neonates. Initial first hour of neonatal life includes neonatal resuscitation, post-resuscitation care, transportation of sick newborn to neonatal intensive care unit, respiratory and cardiovascular support and initial course in nursery. The studies that evaluated the concept of golden hour in preterm neonates showed marked reduction in hypothermia, hypoglycemia, intraventricular hemorrhage (IVH), bronchopulmonary dysplasia (BPD), and retinopathy of prematurity (ROP). In this review article, we will discuss various components of neonatal care that are included in "Golden hour" of preterm and term neonatal care.

Sonication contribution to identifying prosthetic joint infection with Ralstonia pickettii: a case report and review of the literature

Background

In the context of an increase number of primary and revision total hip and total knee arthroplasty performed yearly, an increased risk of complication is expected. Prosthetic joint infection (PJI) remains the most common and feared arthroplasty complication. Ralstonia pickettii is a Gram-negative bacterium, that has also been identified in biofilms. It remains an extremely rare cause of PJI. There is no report of an identification of R. pickettii on an extracted spacer loaded with antibiotic.

Case presentation

We present the case of an 83-years-old Caucasian male patient, that underwent a right cemented total hip replacement surgery. The patient is diagnosed with an early PJI with no isolated microorganism. A debridement and change of mobile parts is performed. At the beginning of 2016, the patient in readmitted into the Orthopedic Department for sever, right abdominal and groin pain and elevated serum erythrocyte sedimentation rate and C-reactive protein. A joint aspiration is performed with a negative microbiological examination. A two-stage exchange with long interval management is adopted, and a preformed spacer loaded with gentamicin was implanted. In July 2016, based on the proinflammatory markers evolution, a shift a three-stage exchange strategy is decided. In September 2016, a debridement, and changing of the preformed spacer loaded with gentamicin with another was carried out. Bacteriological examination of the tissues sampled intraoperatively was positive for Pseudomonas aeruginosa. From the sonication fluid, no bacteria were isolated on culture or identified using the bbFISH assay. During the hospitalization period, the patient received i.v. ceftazidime 3x2g/day and p.o. ciprofloxacin 2x750mg/day, antibiotic therapy that was continued after discharge with p.o. ciprofloxacin 2x750mg/day for 6 weeks. In February 2017, a reimplantation of a revision prosthesis is performed. The retrieved spacer is sonicated, and after 4 days of incubation of the sonication fluid, R. pickettii is isolated. A long term antibiotic therapy with cotrimoxazole being prescribed.

Conclusions

Bacteria culture of sonication fluid remains the gold standard in diagnosing prosthetic joint infections. R. pickettii remains an extremely rare cause of prosthetic joint infection. Optimal management of R. pickettii prosthetic joint infections of has not been established.

Biomarkers for diagnosis of neonatal sepsis: a literature review

Sepsis is an important cause of mortality and morbidity in neonatal populations. There has been constant search of an ideal sepsis biomarker that have high sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV), so that both the diagnosis and exclusion of neonatal sepsis can be made at the earliest possible and appropriate antibiotics can be started to neonate. Ideal sepsis biomarker will help in guiding us when not to start antibiotics in case of suspect sepsis and total duration of antibiotics course in case of proven sepsis. There are numerous sepsis biomarkers that have been evaluated for early detection of neonatal sepsis but till date there is no single ideal biomarker that fulfills all essential criteria's for being an ideal biomarker. The most commonly used biomarkers are C-reactive protein (CRP) and procalcitonin (PCT), but both have shown varied sensitivity, specificity, PPV and NPV in different studies. We conducted literature search for various neonatal sepsis biomarkers and this review article will cover briefly all the markers with current available evidence.