The Kingella kingae PilC1 MIDAS Motif Is Essential for Type IV Pilus Adhesive Activity and Twitching Motility.

Kingella kingae is an emerging pathogen that has recently been identified as a leading cause of osteoarticular infections in young children. Colonization with K. kingae is common, with approximately 10% of young children carrying this organism in the oropharynx at any given time. Adherence to epithelial cells represents the first step in K. kingae colonization of the oropharynx, a prerequisite for invasive disease. Type IV pili and the pilus-associated PilC1 and PilC2 proteins have been shown to mediate K. kingae adherence to epithelial cells, but the molecular mechanism of this adhesion has remained unknown. Metal ion-dependent adhesion site (MIDAS) motifs are commonly found in integrins, where they function to promote an adhesive interaction with a ligand. In this study, we identified a potential MIDAS motif in K. kingae PilC1 which we hypothesized was directly involved in mediating type IV pilus adhesive interactions. We found that the K. kingae PilC1 MIDAS motif was required for bacterial adherence to epithelial cell monolayers and extracellular matrix proteins and for twitching motility. Our results demonstrate that K. kingae has co-opted a eukaryotic adhesive motif for promoting adherence to host structures and facilitating colonization.

Oral Versus Intravenous Antibiotics for Pediatric Osteoarticular Infection: When and to Whom?

BACKGROUND: Osteoarticular infections (OAIs) are typically treated initially with intravenous antibiotics. The objective of this study was to evaluate whether an exclusive oral treatment in selected children may be appropriate. METHODS: The Spanish Network of Osteoarticular Infections is a nationwide multicenter registry comprising 37 hospitals in Spain. The registry prospectively includes clinical characteristics and outcome of children with OAI. One of the hospitals from RioPed offers oral treatment to children meeting certain criteria. Patients were classified into 2 groups. Group 1: management with initial intravenous antibiotic therapy. Group 2: patients exclusively treated with oral antibiotics. A comparison between the 2 groups was performed. RESULTS: We compared 893 children who initially received intravenous antibiotics (group 1) with 64 children who received exclusively oral therapy (group 2). Patients from group 2 were younger (33.9 vs. 20.3 months; P = 0.001), had a lower percentage of Staphylococcus aureus (23.3% vs. 3.1%; P < 0.001), a higher proportion of Kingella kingae (12.1% vs. 28.1%; P = 0.001), higher erythrocyte sedimentation rate/C-reactive protein (CRP) ratio (1.4 interquartile range 0.6-3.6 vs. 3.3 interquartile range 1.7-5.7; P < 0.001) and showed lower rate of fever (63% vs. 48.8%; P = 0.024) than in group 1. Complications were not found in group 2. CONCLUSIONS: An exclusively oral administration could be a safe option in selected patients with OAI. Low-risk criteria are proposed: good general condition, no underlying disease, 6 months to 3 years old, appropriate oral tolerance, C-reactive protein <80 mg/L, erythrocyte sedimentation rate/C-reactive protein ratio ≥0.67, no skin injury, no recent surgery, no cervical spondylodiscitis and no local complications at onset.

Native joint infections in Iceland 2003-2017: an increase in postarthroscopic infections.

OBJECTIVES: Nationwide study on the epidemiology, clinical characteristics and outcomes among patients with native joint infection (NJI) in Iceland, 2003-2017. METHODS: All positive synovial fluid culture results in Iceland were identified and medical records reviewed. RESULTS: A total of 299 NJI (40 children and 259 adults) were diagnosed in Iceland in 2003-2017, with a stable incidence of 6.3 cases/100 000/year, but marked gender difference among adults (33% women vs 67% men, p<0.001). The knee joint was most commonly affected, and Staphylococcus aureus was the most common isolate in both adults and children, followed by various streptococcal species in adults and Kingella kingae in children. NJI was iatrogenic in 34% of adults (88/259) but comprised 45% among 18-65 years and a stable incidence. Incidence of infections following arthroscopic procedures in adults increased significantly compared with the previous decade (9/100 000/year in 1990-2002 vs 25/100 000/year in 2003-2017, p<0.01) with no significant increase seen in risk per procedure. The proportion of postarthroscopic NJI was 0.17% overall but 0.24% for knee arthroscopy. Patients with postarthroscopic infection were more likely to undergo subsequent arthroplasty when compared with other patients with NJI (p=0.008). CONCLUSIONS: The incidence of NJI in Iceland has remained stable. The proportion of iatrogenic infections is high, especially among young adults, with an increase seen in postarthroscopic infections when compared with the previous decade. Although rare, NJI following arthroscopy can be a devastating complication, with significant morbidity and these results, therefore, emphasise the need for firm indications when arthroscopic treatment is considered.

Proinflammatory Microenvironment During Kingella kingae Infection Modulates Osteoclastogenesis.

Kingella kingae is an emerging pathogen that causes septic arthritis, osteomyelitis, and bacteremia in children from 6 to 48 months of age. The presence of bacteria within or near the bone is associated with an inflammatory process that results in osteolysis, but the underlying pathogenic mechanisms involved are largely unknown. To determine the link between K. kingae and bone loss, we have assessed whether infection per se or through the genesis of a pro-inflammatory microenvironment can promote osteoclastogenesis. For that purpose, we examined both the direct effect of K. kingae and the immune-mediated mechanism involved in K. kingae-infected macrophage-induced osteoclastogenesis. Our results indicate that osteoclastogenesis is stimulated by K. kingae infection directly and indirectly by fueling a potent pro-inflammatory response that drives macrophages to undergo functional osteoclasts via TNF-α and IL-1ß induction. Such osteoclastogenic capability of K. kingae is counteracted by their outer membrane vesicles (OMV) in a concentration-dependent manner. In conclusion, this model allowed elucidating the interplay between the K. kingae and their OMV to modulate osteoclastogenesis from exposed macrophages, thus contributing to the modulation in joint and bone damage.

Children with Primary Septic Arthritis Have a Markedly Lower Risk of Adverse Outcomes Than Those with Contiguous Osteomyelitis.

BACKGROUND: It is widely believed that septic arthritis poses a risk of joint destruction and long-term adverse outcomes for children if not treated emergently. In the present study, children who had primary confirmed septic arthritis were compared with those who had septic arthritis and adjacent osteomyelitis to evaluate differences that affect the relative risk of adverse outcomes. METHODS: Children who underwent multidisciplinary treatment for septic arthritis with or without contiguous osteomyelitis between 2009 and 2019 were retrospectively studied. Clinical, laboratory, treatment, and outcome data were compared between cohorts of children with primary confirmed septic arthritis and children with septic arthritis and contiguous osteomyelitis. RESULTS: One hundred and thirty-four children had primary confirmed septic arthritis, and 105 children had septic arthritis with contiguous osteomyelitis. Children with osteomyelitis were older (median, 7.4 versus 2.4 years), had higher initial C-reactive protein (median, 15.7 versus 6.4 mg/dL), and had a higher rate of thrombocytopenia (21.0% versus 1.5%). They also had a higher rate of bacteremia (69.5% versus 20.2%) for a longer duration (median, 2.0 versus 1.0 days). Detected pathogens in children with osteomyelitis as compared with those with primary septic arthritis were more likely to be Staphylococcus aureus (77.1% versus 32.1%) and less likely to be Kingella kingae (2.9% versus 32.1%). Children with contiguous osteomyelitis had longer hospitalizations (median, 8.0 versus 4.0 days), a higher rate of intensive care (21.0% versus 1.5%), a higher readmission rate (17.1% versus 5.2%), and a higher complication rate (38.1% versus 0.7%). CONCLUSIONS: Primary septic arthritis in children is dissimilar to septic arthritis associated with osteomyelitis. The present study demonstrates that long-term adverse outcomes in children with septic arthritis are likely due to the contiguous osteomyelitis. Children with primary septic arthritis are sufficiently distinguishable from those who have contiguous osteomyelitis to guide decisions for magnetic resonance imaging acquisition, duration of antibiotic therapy, and length of outpatient follow-up in order to recognize and address adverse outcomes. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Binding of Kingella kingae RtxA Toxin Depends on Cell Surface Oligosaccharides, but Not on ß2 Integrins.

The Gram-negative coccobacillus Kingella kingae is increasingly recognized as an important invasive pediatric pathogen that causes mostly bacteremia and skeletal system infections. K. kingae secretes an RtxA toxin that belongs to a broad family of the RTX (Repeats in ToXin) cytotoxins produced by bacterial pathogens. Recently, we demonstrated that membrane cholesterol facilitates interaction of RtxA with target cells, but other cell surface structures potentially involved in toxin binding to cells remain unknown. We show that deglycosylation of cell surface structures by glycosidase treatment, or inhibition of protein N- and O-glycosylation by chemical inhibitors substantially reduces RtxA binding to target cells. Consequently, the deglycosylated cells were more resistant to cytotoxic activity of RtxA. Moreover, experiments on cells expressing or lacking cell surface integrins of the ß2 family revealed that, unlike some other cytotoxins of the RTX family, K. kingae RtxA does not bind target cells via the ß2 integrins. Our results, hence, show that RtxA binds cell surface oligosaccharides present on all mammalian cells but not the leukocyte-restricted ß2 integrins. This explains the previously observed interaction of the toxin with a broad range of cell types of various mammalian species and reveals that RtxA belongs to the group of broadly cytolytic RTX hemolysins.

Endovascular Infection with Kingella kingae Complicated by Septic Arthritis in Immunocompromised Adult Patient.

We report a case of Kingella kingae endovascular infection in an immunocompromised elderly patient in Israel who had culture-negative septic arthritis. This case highlights potential sources of metastatic infection other than infective endocarditis, and emphasizes the need for molecular diagnostic methods in detection of pathogens in culture-negative septic arthritis in immunocompromised patients.

Endogenous endophthalmitis due to Kingella Kingae infectious endocarditis / Endoftalmite endógena por endocardite infecciosa devido a Kingella Kingae

Abstract This report presents a rare case of endogenous endophthalmitis due to Kingella kingae infectious endocarditis. Endogenous endophthalmitis is a rare condition that has a systemic underlying cause, with hematogenic dissemination of a pathogen that will eventually reach and infect the eye. In this article, we present a case of a 54-year-old woman with fever, chills and decreased visual acuity and pain in the right eye. The slit-lamp exam showed conjunctival injection, anterior chamber reaction with a great amount of fibrinous material obscuring her visual axis. Ultrasound echography revealed profuse exudates and scarce membranous formation in the posterior segment. Blood culture was positive for Kingella kingae, and the patient was treated with intravenous ceftriaxone, along with topic dexamethasone and mydriatic. After 15 days of intravenous antibiotic therapy, the patient exhibited best visual acuity of 20/60. Endogenous endophthalmitis is an ocular emergency that demands quick diagnosis and aggressive intervention in order to preserve vision. Therefore, it is important to recognize its signs and symptoms with no retard.

Resumo O presente relato apresenta um raro caso de endoftalmite endógena por endocardite devido à Kingella kingae. Endoftalmite endógena é uma doença pouco comum com uma causa sistêmica subjacente. A disseminação hematogênica de um microrganismo infeccioso leva à infecção ocular. Nesse artigo, apresentamos o caso de uma mulher com 54 anos, febre, calafrios, baixa da acuidade visual e dor em olho direito. Ao exame na lâmpada de fenda apresentava injeção conjuntival, reação de câmara anterior e acúmulo de fibrina no eixo visual. Ultrassonografia revelou exsudatos profusos e escassa formação membranosa em segmento posterior.A hemocultura foi positiva para Kingella kingae e a paciente foi tratada com ceftriaxone venoso conjuntamente com dexametasona e midriático tópicos. Após 15 dias de terapia antibiótica endovenosa, a paciente apresentou acuidade visual corrigida de 20/60. Endoftalmite endógena é uma emergência ocular que demanda rápido diagnóstico e intervenção agressiva para preservar a visão. Portanto, é importante o reconhecimento precoce dos sinais e sintomas.

[Osteo-articular infections by Kingella kingae in children in a highly complex pediatric hospital: epidemiology and associated factors]. / Infecciones osteo-articulares por Kingella kingae en niños en un hospital pediátrico de alta complejidad: epidemiología y factores asociados.

BACKGROUND: The epidemiology of osteoarticular infections (IOA) has changed in recent years. The incidence of Kingella kingae in Latin America is unknown. AIMS: To describe the epidemiology in patients with IOA in a children hospital. To estimate the incidence of IOA due to K. kingae and compare with other etiologies. METHODS: Prospective cohort. Patients older than 1 month hospitalized between March, 1th 2017 and February, 28th 2019 with suspected IOA and diagnostic procedure (biopsy or arthrocentesis) were included. STATA 13 was used. RESULTS: n: 84 patients. The etiology was identified in 58 patients (69.1%). Staphylococus aureus predominated (n: 44; 52.4%) and K. kingae (n: 9; 10.8%). In the period studied, the incidence of IOA by K. kingae was 10.8 cases per 100 hospitalized IOA. In multivariate analysis, age less than 4 years (OR 13.8, 95% CI 5.5-82.7), recent respiratory symptoms (OR 5.7, 95% CI 3.5-31.6, p 0.04) and normalization before the fifth day of C-reactive protein (CRP) (OR 3.38 95% CI 1.8-16.3, p 0.01) were associated with IOA by K. kingae. CONCLUSIONS: In this cohort of children the incidence of K. kingae was 10.8 cases per 100 IOA. Kingella kingae represented the second documented etiology, after S. aureus. Age under 4 years, recent respiratory symptoms and normalization before the fifth day of quantitative CRP were statistically associated with IOA by K. kingae.

Microbiología clínica: nuevos desafíos / Clinical microbiology: mew challenges

Si partimos de que la microbiología es una ciencia fundante, podemos estar de acuerdo también en la necesidad de la continua actualización de sus contenidos y su vinculación con la odontología. Nuevas técnicas de diagnóstico permiten, no solo poder identificar características especiales de cada microorganismo y su reubicación en la taxonomía general, sino también habilitan a reconocer a aquellos ­hasta el momento­ desconocidos en la cotidianeidad de la práctica profesional y que revisten importancia por sus afecciones sistémicas ya que pueden transformar, en algunos casos, a que el paciente sea considerado de riesgo. En este trabajo, se abordan tres ejemplares bacterianos seleccionados por su complejidad en la identificación y por la magnitud de las lesiones que producen. Granulicatella spp., Kingela kingae y Bilophila wadsworthia afectan no solo adultos sino también pacientes pediátricos, siendo afectados por patologías severas. Se describen cuadros clínicos que afectan tejido óseo, corazón, cerebro, hígado, bazo, riñón y las manifestaciones orales a las cuales pueden asociarse grupos microbianos que agravan el pronóstico. Aplicar la tecnología adecuadamente, no solo a procedimientos odontológicos, sino también para diagnóstico (PCR ­ MALDI ­ TOF) facilita la detección e identificación con mayor celeridad de estos agentes microbianos, evitando la rotación farmacológica, la resistencia microbiana y la automedicación (AU)

Considering microbiology as a key science in the approach of infectious processes, we understand the need for a continuous update of its contents and its link with dentistry. The incorporation of new technological approaches, such as molecular methods or mass spectrometry, allow us not only to identify special characteristics of the microorganism and its relocation in taxonomy, but also to know those microorganisms until now unknown in professional´s life everyday practice and that are important for their systemic implications, modifying in some cases, the risk assessment of the patient. Three bacterial specimens are developed in this work, due to their complexity in the identification and the magnitude of the lesions they produce, Granulicatella spp., Kingela kingae and Bilophila wadsworthia. These affects both adult and paediatric patients, describing several clinical conditions that affect bone tissue, heart, brain, liver, spleen, kidney and oral manifestations to which these microbial groups can be associated, aggravating the prognosis. Applying new technology, not only to dental procedures but also to diagnosis, facilitates the detection and identification with greater speed of these microbial agents, avoiding pharmacological rotation, microbial resistance and self-medication (AU)

Infecciones osteo-articulares por Kingella kingae en niños en un hospital pediátrico de alta complejidad: epidemiología y factores asociados / Osteo-articular infections by Kingella kingae in children in a highly complex pediatric hospital: epidemiology and associated factors

Resumen Introducción: La epidemiología de las infecciones osteo-articulares (IOA) se ha modificado en los últimos años. La incidencia de Kingella kingae en Latinoamérica es desconocida. Objetivo: Describir la epidemiología de los niños con IOA. Estimar la incidencia de IOA causadas por K. kingae y compararlas con otras etiologías. Material y Métodos: Cohorte prospectiva. Se incluyeron pacientes mayores de 1 mes de edad, hospitalizados entre el 1 de marzo de 2017 y 28 de febrero de 2019, con sospecha de IOA y procedimiento diagnóstico (biopsia o artrocentesis). Se utilizó STATA 13. Resultados: n: 84 pacientes. Se identificó la etiología en 58 pacientes (69,1%). Predominaron Staphylococcus aureus (n: 44; 52,4%) y K. kingae (n: 9; 10,8%). En el período estudiado, la incidencia de IOA por K. kingae fue de 10,8 casos cada 100 IOA hospitalizadas. En el análisis multivariado, la edad inferior a 4 años (OR 13,8, IC95% 5,5-82,7), el cuadro respiratorio reciente (OR 5,7, IC95% 3,5-31,6, p 0,04) y la normalización antes del quinto día de la proteína C reactiva (PCR) (OR 3,8 IC95% 1,8- 16,3, p 0,01) se asociaron con las IOA por K. kingae. Conclusiones: En esta cohorte de niños, la incidencia de K.kingae fue de 10,8 casos cada 100 IOA. Kingella kingae representó la segunda etiología documentada, luego de S. aureus. La edad inferior a 4 años, el cuadro respiratorio reciente y la normalización antes del quinto día de la PCR cuantitativa se asociaron estadísticamente con IOA por K. kingae.

Abstract Background: The epidemiology of osteoarticular infections (IOA) has changed in recent years. The incidence of Kingella kingae in Latin America is unknown. Aims: To describe the epidemiology in patients with IOA in a children hospital. To estimate the incidence of IOA due to K. kingae and compare with other etiologies. Methods: Prospective cohort. Patients older than 1 month hospitalized between March, 1th 2017 and February, 28th 2019 with suspected IOA and diagnostic procedure (biopsy or arthrocentesis) were included. STATA 13 was used. Results: n: 84 patients. The etiology was identified in 58 patients (69.1%). Staphylococus aureus predominated (n: 44; 52.4%) and K. kingae (n: 9; 10.8%). In the period studied, the incidence of IOA by K. kingae was 10.8 cases per 100 hospitalized IOA. In multivariate analysis, age less than 4 years (OR 13.8, 95% CI 5.5-82.7), recent respiratory symptoms (OR 5.7, 95% CI 3.5-31.6, p 0.04) and normalization before the fifth day of C-reactive protein (CRP) (OR 3.38 95% CI 1.8-16.3, p 0.01) were associated with IOA by K. kingae. Conclusions: In this cohort of children the incidence of K. kingae was 10.8 cases per 100 IOA. Kingella kingae represented the second documented etiology, after S. aureus. Age under 4 years, recent respiratory symptoms and normalization before the fifth day of quantitative CRP were statistically associated with IOA by K. kingae.

Osteoarticular infections in pediatrics / Infecções osteoarticulares em pediatria

Abstract Objective To collect the most up-to-date information regarding pediatric osteoarticular infections, including the epidemiological and microbiological profiles, diagnosis, and treatment. Source of data A non-systematic review was performed on the search engines PubMed, SciELO, LILACS, and Google Scholar, using the keywords "bone and joint infection", "children", "pediatric", "osteomyelitis", "septic arthritis" and "spondylodiscitis" over the last ten years. The most relevant articles were selected by the authors to constitute the database. Synthesis of data Osteoarticular infections are still a major cause of morbidity in pediatrics. Their main etiology is Staphylococcus aureus, but there has been an increase in the detection of Kingella kingae, especially through molecular methods. Microbiological identification allows treatment direction, while evidence of inflammatory activity assists in treatment follow-up. Imaging tests are especially useful in the initial diagnosis of infections. Empirical treatment should include coverage for the main microorganisms according to the age and clinical conditions of the patient, while considering the local resistance profile. Surgical procedures can be indicated for diagnosis, focus control, and function preservation. Acute complications include sepsis, deep venous thrombosis, and pulmonary embolism. Deaths are rare. Late complications are uncommon but may lead to deformities that compromise motor development. Conclusion A correct and early diagnosis, prompt implementation of adequate antimicrobial therapy, and focus control, when indicated, are critical to a better prognosis.

Resumo Objetivo Compilar as informações mais atuais referentes às infecções ostoarticulares em pediatria, inclusive perfil epidemiológico e microbiológico, diagnóstico e tratamento. Fonte dos dados Feita revisão não sistemática nos mecanismos de busca Pubmed, Scielo, Lilacs e Google Scholar, com as palavras-chave bone and joint infection, children, pediatric, osteomyelitis, septic arthritis e espondylodiscitis nos últimos 10 anos. Os artigos mais relevantes foram selecionados pelos autores para compor a base de dados. Síntese dos dados As infecções osteoarticulares ainda são causa importante de morbidade na pediatria. A sua principal etiologia é o Staphylococcus aureus, porém há um aumento na detecção de Kingella kingae, especialmente através de métodos moleculares. A identificação microbiológica possibilita direcionamento de tratamento, enquanto que as provas de atividade inflamatória auxiliam no acompanhamento do tratamento. Exames de imagem são especialmente úteis no diagnóstico inicial das infecções. O tratamento empírico deve incluir cobertura para os principais microrganismos, de acordo com a faixa etária e as condições clínicas do paciente, considerando o perfil de resistência local. Procedimentos cirúrgicos podem ser indicados para diagnóstico, controle do foco e preservação da função. As complicações agudas incluem sepse, trombose venosa profunda e embolia pulmonar. Óbitos são raros. As complicações tardias são incomuns, mas podem levar a deformidades que comprometem o desenvolvimento motor. Conclusão O diagnóstico correto e precoce, com pronta instituição de terapia antimicrobiana adequada e controle do foco, quando indicado, é fundamental para um melhor prognóstico.

Validation of a novel molecular diagnostic panel for pediatric musculoskeletal infections: Integration of the Cepheid Xpert MRSA/SA SSTI and laboratory-developed real-time PCR assays for clindamycin resistance genes and Kingella kingae detection.

BACKGROUND: Pathogen detection in pediatric patients with musculoskeletal infections relies on conventional bacterial culture, which is slow and can delay antimicrobial optimization. The ability to rapidly identify causative agents and antimicrobial resistance genes in these infections may improve clinical care. METHODS: Convenience specimens from bone and joint samples submitted for culture to Children's Hospital Colorado (CHCO) from June 2012 to October 2016 were evaluated using a "Musculoskeletal Diagnostic Panel" (MDP) consisting of the Xpert MRSA/SA SSTI real-time PCR (qPCR, Cepheid) and laboratory-developed qPCRs for Kingella kingae detection and erm genes A, B, and C which confer clindamycin resistance. Results from the MDP were compared to culture and antimicrobial susceptibility testing (AST) results. RESULTS: A total of 184 source specimens from 125 patients were tested. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the Xpert MRSA/SA SSTI compared to culture and AST results were 85%, 98%, 93%, and 95% respectively for MSSA and 82%, 100%, 100%, and 99% for MRSA. Compared to phenotypic clindamycin resistance in S. aureus isolates, the erm A, B, and C gene PCRs collectively demonstrated a sensitivity, specificity, PPV, and NPV of 80%, 96%, 67%, and 98%. In comparison to clinical truth, Kingella PCR had a sensitivity, specificity, PPV, and NPV of 100%, 99.5%, 100%, and 100%. CONCLUSIONS: This novel MDP offers a rapid, sensitive, and specific option for pathogen detection in pediatric patients with musculoskeletal infections.

Kingella kingae Septic Arthritis in an Older-Than-Expected Child.

Kingella kingae typically causes musculoskeletal infection in young children between the ages of 6 months and 4 years who may be in close contact with other similarly aged children who are colonized with the organism in their oropharynx. Kingella infections have rarely been described in older individuals with chronic medical conditions or immune compromise. This is a case report of a healthy, older child who developed an invasive infection due to Kingella kingae. Clinical and laboratory details are provided of an otherwise healthy 11-year-old female who developed an acute onset of septic arthritis of her shoulder. The organism was identified by culture and 16S polymerase chain reaction. Her clinical course necessitated an antibiotic change after the organism was correctly identified. The affected child had close contact with a 2-year-old sibling who recently had a viral upper respiratory infection. This case illustrates the potential for Kingella kingae to rarely cause invasive infection in older, healthy children. Supplemental laboratory techniques may be helpful to identify this organism. Although it is reasonable to limit the antibiotic spectrum for older children, clinicians should be aware of this possibility, particularly if there is a history of close contact with young children.

Espondilodiscitis por Kingella kingae: A propósito de un caso de presentación atípica / Atypical presentation of Spondylodiscitis by Kingella Kingae: a case report

La espondilodiscitis infecciosa es una infección poco frecuente en niños, con mayor incidencia en menores de 6 años. Se presenta el caso de una paciente de 8 años, que se internó por dolor lumbar de 2 meses de evolución, afebril. La radiografía, tomografía e imagen por resonancia magnética nuclear fueron compatibles con espondilodiscitis a nivel de L4-L5. Luego de 10 días de antibioticoterapia empírica con clindamicina, con regular respuesta, se realizó punción ósea y se aisló Kingella kingae. Existe un aumento en la incidencia de infecciones osteoarticulares por Kingella kingae en lactantes y niños pequeños. La reemergencia en los últimos años se justifica por la optimización en las técnicas de cultivo, el uso de sistemas automatizados y de técnicas moleculares de diagnóstico. Kingella kingae es un patógeno que ha adquirido importancia en los últimos años en las infecciones osteoarticulares.

Infectious Spondylodiscitis is a rare infection in children. It is more frequent in patients under 6 years of age. We report the case of an 8-year-old patient with lumbar pain for 2 months, without fever. Xrays, computed tomography and magnetic resonance imaging all three showed spondylodiscitis L4-L5. After a 10-day antibiotic treatment with clindamycin with regular response, a bone puncture was performed isolating Kingella kingae (Kk). Ostearticular infections caused by Kk have increased among infants and children. Due to improvement in culture techniques, the usage of automatic systems and assessment molecular techniques, these infections re-emerged in the past few years. Kk is a pathogen that has lately become significant in osteoarticular infections.

ECMO en un lactante con shock cardiogénico secundario a endocarditis por Kingella Kingae / ECMO support in a child with cardiogenic shock due to Kingella Kingae endocarditis

Resumen: Introducción: La endocarditis es una enfermedad poco frecuente en niños, especialmente en los sin patología cardiaca previa, y de manera extraordinaria se identifica a Kingella Kingae (KK) como la causa. La oxigenación por membrana extracorpórea (ECMO) es una forma de soporte tanto para fa lla cardiaca como respiratoria. Objetivo: Reportar el primer caso de endocarditis infecciosa (EI) por KK que requiere soporte con ECMO por shock cardiogénico refractario. Caso clínico: Lactante de 19 meses, previamente sana, que consultó por cuadro de 2 días de fiebre, diagnosticándose síndrome pie mano boca. Evolucionó con shock, falla multiorgánica, síndrome de distress respiratorio agudo y compromiso hemodinámico profundo, por lo que se le dio soporte con ECMO veno arterial. La ecoscopía mostró imagen compatible con vegetación en válvula mitral, confirmando EI con ecocardiografía transtorácica. El hemocultivo fue positivo a KK. Presentó accidente cerebrovascular isquémico. Requirió dos cardiocirugías -la primera para resección de la masa y la segunda para la reparación de la válvula mitral, que había quedado con un pseudoaneurisma del anillo- velo posterior. La paciente tuvo una evolución favorable, siendo dada de alta a los 73 días desde el ingreso. Al año de seguimien to se encontraba asintomática cardiaca, pero persistía una hemiparesia braquiocrural derecha leve. Conclusión: Este es el primer caso reportado de EI por KK que requirió soporte vital extracorpóreo. La EI por KK es una patología infrecuente, que puede provocar falla orgánica múltiple, la que puede ser soportada exitosamente con ECMO.

Abstract: Introduction: Endocarditis is a rare disease in children, especially in those without previous heart disease, and Kingella Kingae (KK) is rarely identified as the cause. Extracorporeal membrane oxyge nation (ECMO) is a support for both heart and respiratory failure. Objective: To report the first case of infectious endocarditis (IE) due to KK which required ECMO support secondary to refractory cardiogenic shock. Clinical case: 19-months-old previously healthy female patient, with a 2-day his tory of fever, and diagnosed with hand-foot-and-mouth disease. The patient developed refractory cardiogenic shock, multiorgan failure, acute respiratory distress syndrome, and deep hemodynamic compromise that required veno-arterial ECMO support. The echography showed an image compa tible with mitral valve vegetation, confirming IE with transthoracic echocardiography. Blood culture was positive for KK. She had an ischemic stroke and required two heart surgeries, the first one for the mass resection and the second one for mitral valve repair, which had a posterior ring pseudoa neurysm. The patient had a favorable evolution and was discharged 73 days after admission. At one year of follow-up, she had no cardiological symptoms, but a mild right brachial-crural hemiparesis persisted. Conclusion: This is the first reported case of IE due to KK that required extracorporeal life support. KK endocarditis is an uncommon pathology that can cause multiorgan failure, which can be successfully supported with ECMO.

Spinal infections in children: a multicentre retrospective study.

Aims: This multicentre, retrospective study aimed to improve our knowledge of primary pyogenic spinal infections in children by analyzing a large consecutive case series. Patients and Methods: The medical records of children with such an infection, treated at four tertiary institutions between 2004 and 2014, were analyzed retrospectively. Epidemiological, clinical, paraclinical, radiological, and microbiological data were evaluated. There were 103 children, of whom 79 (76.7%) were aged between six months and four years. Results: We confirmed a significant male predominance in the incidence of primary pyogenic spinal infections in children (65%). The lumbar spine was the most commonly affected region, and 27 infections (26.2%) occurred at L4/5. The white blood cell count was normal in 61 children (59%), and the CRP level was normal in 43 (42%). Blood cultures were performed in 95 children, and were positive in eight (8%). A total of 20 children underwent culture of biopsy or aspiration material, which was positive in eight (40%). Methicillin-sensitive Staphylococcus aureus (MSSA) and Kingella ( K.) kingae were the most frequently isolated pathogens. Conclusion: MSSA remains the most frequently isolated pathogen in children with primary pyogenic infection of the spine, but K. kingae should be considered as an important pathogen in children aged between six months and four years. Therefore, an empirical protocol for antibiotic treatment should be used, with consideration being made for the triphasic age distribution and specific bacteriological aetiology. In the near future, the results of polymerase chain reaction assay on throat swabs may allow the indirect identification of K. kingae spondylodiscitis in young children and thus aid early treatment. However, these preliminary results require validation by other prospective multicentre studies. Cite this article: Bone Joint J 2018;100-B:542-8.

Particular surgical aspects of endocarditis due to Kingella kingae with cerebral complication.

We report 2 cases of Kingella kingae endocarditis leading to valvular mitral perforation in previously healthy children. Kingella kingae belongs to the HACEK (Haemophilus aphrophilus, Actiobacillus actinomycetemcomitans, Cardiobacterium hominis, Eikenella corrodens and K. kingae) group of organisms known to cause endocarditis.