Kingella pumchi sp. nov., an organism isolated from human vertebral puncture tissue.

A Gram-negative, non-motile rod and strictly aerobic bacterium, designated as 18B16333T, was isolated from vertebral puncture tissue of a patient at Peking union medical college hospital in China. Growth occurred in NaCl concentrations of 0-1% (w/v) (optimum growth at 0% NaCl), at temperatures of 25-40 °C (optimum growth at 37 °C) and at pH 6.0-9.0 (optimum growth at pH 8.0). Diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine were the predominant polar lipids, and the major fatty acids were C16:0, C18:1 ω7c/C18:1 ω6c and C16:1 ω7c/C16:1 ω6c. Phylogenetic analysis based on 16S rRNA gene sequence comparisons indicated that strain 18B16333T was most closely related to Kingella potus CCUG 49773 T (97.3%, 16S rRNA gene sequence identity) and Neisseria bacilliformis CCUG 50858 T (96.8%). The ANI values between strain 18B16333T and the type strains K. potus CCUG 49773 T, N. bacilliformis CCUG 50858 T, Kingella kingae CCUG 352 T and Neisseria gonorrhoeae CCUG 26876 T were 77.3%, 79.1%, 72.1% and 75.4%, respectively. The dDDH values between strain 18B16333T and the four reference strains mentioned above were 24.8%, 26.9%, 24.2% and 20.7%. Further core gene analysis distinctively clustered strain 18B16333T with four Kingella species but not with Neisseria species. Based on the phenotypic, chemotaxonomic, and phylogenetic properties, strain 18B16333T represents a novel species of the genus Kingella, for which the name Kingella pumchi sp. nov. is proposed. The type strain is Kingella pumchi 18B16333T (= CICC 24913 T = CCUG 75125 T).

Detection of Respiratory Colonization by Kingella kingae and the Novel Kingella negevensis Species in Children: Uses and Methodology.

The recognition of the role of Kingella kingae as one of the main etiologic agents of skeletal system infections in young children and the recent discovery of the novel Kingella negevensis species have resulted in an increasing interest in these two emerging pediatric pathogens. Both bacteria colonize the oropharynx and are not detected in nasopharyngeal specimens, and the colonized mucosal surface is their portal of entry to the bloodstream. Although species-specific nucleic acid amplification assays have significantly improved the detection of kingellae and facilitated patients' management, the increasing use of this diagnostic approach has the potential drawback of neglecting culture recovery of these organisms. The isolation of Kingella species enables the thorough genotyping of strains for epidemiological purposes, the study of the dynamics of asymptomatic colonization and person-to-person transmission, the investigation of the pathogenesis of invasive infections, and the determination of antibiotic susceptibility patterns. The culture isolation of pharyngeal strains and their comparison with isolates derived from normally sterile body sites may also aid in identifying virulence factors involved in the transition from colonization to invasive disease which could represent potential targets for a future protective vaccine. The two species are notoriously fastidious, and their isolation from upper respiratory tract specimens requires a short transport time, plating on selective vancomycin-containing blood-agar medium, and incubation under capnophilic and aerobic conditions. The identification of K. kingae and K. negevensis can be performed by a combination of the typical Gram stain and biochemical tests and confirmed and differentiated by molecular assays that target the groEL and mdh genes.

Isolation and characterization of Kingella negevensis sp. nov., a novel Kingella species detected in a healthy paediatric population.

We herein report the isolation and characterization of 21 Gram-stain-negative strains cultivated from the oropharynx of healthy children in Israel and Switzerland. Initially described as small colony variants of Kingella kingae, phenotypic analysis, biochemical analysis, phylogenetic analysis based on sequencing of the partial 16S rRNA gene and five housekeeping genes (abcZ, adk, G6PD, groEL and recA), and whole genome sequencing and comparison between members of the genera Kingella and Neisseria provided evidence for assigning them to the genus Kingella. Cellular fatty acids included important amounts of C12 : 0, C14 : 0, C16 : 0 and C16 : 1n7. Digital DNA-DNA hybridization between the isolates Sch538T and K. kingae ATCC 23330T revealed relatedness of 19.9 %. Comparative analysis of 16S rRNA gene sequences available in GenBank allowed matches to strains isolated in the USA, suggesting a wider geographical distribution. A novel species named Kingella negevensis sp. nov. is proposed, as most strains have been isolated in the Negev, a desert region of southern Israel. The type strain is Sch538T (=CCUG 69806T=CSUR P957).

Empiric antibiotic therapy for acute osteoarticular infections with suspected methicillin-resistant Staphylococcus aureus or Kingella.

The bacterial agents causing bone and joint infections have been changing. Currently, methicillin-resistant Staphylococcus aureus (MRSA) and Kingella kingae are emerging pathogens. For treatment of MRSA infections, clindamycin, vancomycin, and linezolid are commonly prescribed antibiotics. Kingella are sensitive to most penicillins and cephalosporins. Because MRSA osteoarticular infections tend to be severe, longer periods of antibiotic treatment with more frequent monitoring of inflammatory markers are sometimes required to obtain a complete cure with no residual complications. To assist management, we have included a clinical decision tree with antibiotic treatment protocols.

Prosthetic valve endocarditis due to Neisseria elongata subsp. elongata in a patient with Klinefelter's syndrome.

A case is reported of prosthetic valve endocarditis due to Neisseria elongata subsp. elongata in a patient with Klinefelter's syndrome. This is believed to be only the third case of endocarditis reported due to this subspecies. N. elongata is difficult to identify, and is morphologically and biochemically similar to Kingella spp. Sequencing of the 16S rRNA gene is useful for identification. The patient was successfully treated with amoxicillin and gentamicin, followed by ceftriaxone.

Description of Kingella potus sp. nov., an organism isolated from a wound caused by an animal bite.

We report the isolation and characterization of a hitherto unknown gram-negative, rod-shaped Neisseria-like organism from an infected wound resulting from a bite from a kinkajou. Based on both phenotypic and phylogenetic evidence, it is proposed that the unknown organism be classified as a new species, Kingella potus sp. nov.

Increased susceptibility to gingival colonization by specific HACEK microbes in children with congenital heart disease.

It is well established that infective endocarditis (IE) involving the HACEK (Hemophilus, Actinobacillus, Cardiobacter, Eikenella, Kingella) group of microbes occurs in patients with congenital heart defects (CHD) and in those with prosthetic grafts. Dental caries and gingival disease have been presumed to be the focus of microbial shedding. The purpose of this study was to determine if children with CHD had a more severe gingival inflammatory condition and harbored the HACEK group of microbes to a greater extent than normal children. Two groups of 12 age and sex matched children were selected for this study. The experimental group consisted of twelve children with CHD, 1-1/2 to 8 years of age. The control group consisted of 12 healthy children 2 to 8 years of age. Each child had a gingival index score recorded as described by Massler. Subgingival cultures were obtained. Gingival samples were cultured for HACEK microbes and total Streptococcus (spp) using standard techniques. Fisher's exact test was performed with significance defined at P < 0.05. Children with CHD had more severe gingival inflammatory index than the control group (P < 0.05). 8/12 CHD patient had Actinobacillus actinomycetemcomitans (A.a.) as compared with 2/12 controls (P < 0.05). Furthermore, all cyanotic CHD patients (4/4) had A.a. whereas, only 2/12 controls did (P < 0.05). 4/12 CHD patients harbored Eikenella corrodens (E.c.) compared to 1/12 controls (N.S.). There was no significant difference in colonization with E.c. or A.a. between cyanotic and acyanotic patients. No significant difference in total Streptococcus (spp) was found between the two groups. This study suggests that children with CHD have a more severe gingival inflammatory index and are colonized with specific HACEK microbes more so than normal children.

Distribution of a newly described species, Kingella oralis, in the human oral cavity.

The oral distribution of Kingella oralis was investigated in 10 periodontally healthy subjects. 11 untreated adult periodontitis patients and 6 untreated localized juvenile periodontitis patients. From each subject, 6-8 each of supra- and subgingival tooth samples, 4 mucosa samples and a saliva sample were examined by culture for the presence of K. oralis. K. oralis was found in at least one oral site in 26 of the 27 study subjects, and in at least one tooth site in each of these 26 positive subjects. Its prevalence in dental plaque ranged from 23% to 59% in different subject groups. The mean percentage of K. oralis in total microbiota in the dental plaque ranged from 0.40% in the periodontally healthy group to 4.60% in localized juvenile periodontitis subjects. The organism was a significant species in a few periodontitis sites, constituting > 5% of the total microbiota.