Claudine Gysin

Role for early-differentiated natural killer cells in infectious mononucleosis

A growing body of evidence suggests that the human natural killer (NK)-cell compartment is phenotypically and functionally heterogeneous and is composed of several differentiation stages. Moreover, NK-cell subsets have been shown to exhibit adaptive immune features during herpes virus infection in experimental mice and to expand preferentially during viral infections in humans. However, both phenotype and role of NK cells during acute symptomatic Epstein-Barr virus (EBV) infection, termed infectious mononucleosis (IM), remain unclear. Here, we longitudinally assessed the kinetics, the differentiation, and the proliferation of subsets of NK cells in pediatric IM patients. Our results indicate that acute IM is characterized by the preferential proliferation of early-differentiated CD56(dim) NKG2A(+) immunoglobulin-like receptor(-) NK cells. Moreover, this NK-cell subset exhibits features of terminal differentiation and persists at higher frequency during at least the first 6 months after acute IM. Finally, we demonstrate that this NK-cell subset preferentially degranulates and proliferates on exposure to EBV-infected B cells expressing lytic antigens. Thus, early-differentiated NK cells might play a key role in the immune control of primary infection with this persistent tumor-associated virus.

Laryngeal damage due to an unexpectedly large and inappropriately designed cuffed pediatric tracheal tube in a 13-month-old child.

PurposeTo present a case of laryngeal damage in an infant caused by a too large and inappropriately designed cuffed tracheal tube.Clinical featuresA 13-month-old child undergoing cardiac surgery was intubated with an uncuffed endotracheal tube with an internal diameter (ID) of 4.0 mm. Because of an important air leak around the tracheal tube during mechanical ventilation, a cuffed endotracheal tube lD 4.0 mm was inserted. The air leak with the tube cuff not inflated was acceptable at 25 cm H2O airway pressure. After extubation on the third postoperative day the patient showed increasing stridor and respiratory deterioration. Fibreoptic laryngoscopy of the spontaneously breathing patient showed a large intra-laryngeal web. After surgical removal of the web, the child rapidly recovered and was discharged from the hospital on the 12th postoperative day.Inspection of the 4.0 mm (ID) cuffed tracheal tube revealed a cuff positioned inappropriately high and an increase of 0.7 mm in outer tube diameter compared to the 4.0 mm (lD) uncuffed tracheal tube from the same manufacturer. The tube cuff is likely to be situated within the larynx when placed in accordance to insertion depth formulas or radiological criteria, as used for uncuffed tracheal tubes in children.ConclusionThe larger than expected tracheal tube with its intralaryngeal cuff position in a 13-month-old child likely caused mucosal damage and an inflammatory reaction within the larynx resulting in granulation tissue formation and fibrous healing around the tracheal tube.RésuméObjectifPrésenter un cas de lésion laryngée causée, chez un enfant, par un tube trachéal à ballonnet, trop grand et mal conçu. Élémentscliniques : Un enfant de 13 mois devant subir une intervention cardiaque a été intubé avec un tube endotrachéal sans ballonnet d’un diamètre interne (Dl) de 4,0 mm. Étant donné l’importante fuite d’air autour du tube trachéal pendant la ventilation mécanique, un tube endotrachéal à ballonnet de 4,0 mm de Dl a été inséré. La fuite d’air notée autour du ballonnet non gonflé était acceptable pour une pression des voies aériennes de 25 cm H2O. Après l’extubation, au troisième jour postopératoire, le patient a présenté un stridor croissant et une détérioration respiratoire. La fibroscopie du larynx pendant la respiration spontanée a montré une grande membrane intralaryngée. Après le retrait chirurgical de la membrane, l’enfant s’est rapidement rétabli et a quitté l’hôpital le 12e jour.Lexamen du tube à ballonnet de 4,0 mm a révélé un ballonnet placé trop haut et une augmentation de 0,7 mm du diamètre extérieur du tube, comparé au tube sans ballonnet de 4,0 mm réalisé par le même fabricant. Le ballonnet se situe à l’intérieur du larynx quand on place le tube selon les formules d’insertion ou les critères radiologiques, comme on le fait avec les tubes trachéaux sans ballonnets chez les enfants.ConclusionLe tube trachéal, plus gros que prévu, placé dans le larynx dans la position indiquée pour un tube à ballonnet chez un enfant de 13 mois, a causé une lésion de la muqueuse et une réaction inflammatoire dans le larynx, ce qui a entraîné la formation de tissu de granulation et une cicatrisation fibreuse autour du tube trachéal.

Pediatric tracheotomy: A 30-year experience

BACKGROUND/PURPOSE The aim of this study was to investigate changes of pediatric tracheotomy practice over time. METHODS A retrospective analysis of all tracheotomies at the University Childrens Hospital Zurich from January 1990 to December 2009 was performed. Data analyzed included the indication for tracheotomy, patient comorbidities, age, duration of cannulation, and complications. The second part of the study consisted of comparing our results with data from an earlier study done at the same institution by Simma et al. (Eur J Pediatr 1994;153:291-296) reviewing the patients with tracheotomies treated from 1979 to 1989. RESULTS Between 1990 and 2009, 119 patients were included. The indication for tracheotomy was airway obstruction in 70% and prolonged ventilation in 30%. 70% of the patients were operated on before 1 year of age. Serious postoperative complications occurred in 25 patients (23%). There was one death related to tracheotomy. Successful decannulation was achieved in 60%, on average 28 months after tracheotomy. The decannulation rate in patients with airway obstruction was 74% compared to 52% for the patients in prolonged ventilation group; a statistically significant difference was observed (p < 0.05). The longitudinal analysis showed an increase of indications for prolonged ventilation and a trend toward decreased tracheotomy complications. CONCLUSION Over 30 years, a shift in the indications of pediatric tracheotomy, with an increasing number of procedures performed for prolonged ventilation, was found. The tracheotomy-related mortality was under 1%. Tracheotomy remains a valid and safe option for pediatric patients. Level of evidence 2c.

Kaposiform hemangioendothelioma arising in the ethmoid sinus of an 8-year-old girl with severe epistaxis.

Epistaxis is very common during childhood. It occurs primarily in boys and is usually self‐limiting. Trauma and nose picking are among the most common causes. In general, epistaxis can be easily treated with anterior nasal packing or electrocoagulation.

Pituitary duplication and nasopharyngeal teratoma in a newborn: CT, MRI, US and correlative histopathological findings.

The computed tomography and MRI imaging findings in a case of pituitary duplication and epipharyngeal teratoma are described in a newborn baby girl with respiratory difficulties. Associated skull base and central nervous system malformations are presented. Teratoma diagnosis was confirmed by histology. The embryological pathogenesis is discussed.

Pediatric Epstein-Barr Virus Carriers With or Without Tonsillar Enlargement May Substantially Contribute to Spreading of the Virus

BACKGROUND Human-to-human transmission of the persistent infection establishing Epstein-Barr virus (EBV) occurs via saliva. Tonsils act as important portal of entry and exit of EBV. The contagiousness of pediatric EBV carriers and the role played by tonsillar enlargement (TE) are not known. METHODS We compared EBV shedding in mouthwash samples from pediatric EBV carriers with or without TE to that in mouthwash samples from pediatric patients with infectious mononucleosis (IM), the symptomatic form of primary infection if delayed after the age of 5 years. EBV DNA was quantified by polymerase chain reaction, and contagiousness was assessed using the cord lymphocyte transformation assay. RESULTS EBV carriers with TE shed EBV DNA at an almost similar frequency (although in lower amounts) as pediatric patients with acute IM but more frequently (P <.001) and in higher amounts (P = .038) than EBV carriers without TE. EBV DNA levels in mouthwash samples from EBV carriers with TE mirrored levels in tonsils and gradually declined after tonsillectomy. Almost half of the mouthwash samples from pediatric EBV carriers contained infectious EBV. CONCLUSIONS Pediatric EBV carriers--in particular, those with TE-may considerably contribute to the spreading of EBV in industrialized countries.

Oropharyngeal Group A Streptococcal Colonization Disrupts Latent Epstein-Barr Virus Infection

Epstein-Barr virus (EBV) infects >90% of the human population within the first 2 decades of life and establishes reversible latent infection in B cells. The stimuli that lead to switching from latent to lytic EBV infection in vivo are still elusive. Group A streptococci (GAS) are a common cause of bacterial pharyngotonsillitis in children and adolescents and colonize the tonsils and pharynx of up to 20% of healthy children. Thus, concomitant presence of EBV and GAS in the same individual is frequent. Here, we show that EBV carriers who are colonized with GAS shed EBV particles in higher numbers in their saliva, compared with EBV carriers not colonized with GAS. Messenger RNA levels of the master lytic regulatory EBV gene BZLF1 were more frequently detected in tonsils from EBV carriers colonized with GAS than from EBV carriers not colonized. Heat-killed GAS, potentially mimicking GAS colonization, elicited lytic EBV in latently infected lymphoblastoid cell lines (LCLs) partially via Toll-like receptor 2 triggering, as did purified GAS peptidoglycan. Thus, colonization by GAS might benefit EBV by increasing the EBV load in saliva and thereby enhancing the likelihood of EBV spread to other hosts.

The prevalence of tracheal bronchus in pediatric patients undergoing rigid bronchoscopy.

Background:Tracheal bronchus (TB) is defined as an abnormal bronchus that originates directly from the lateral wall of the trachea above the carina and goes towards the upper lobe territory of the lung. We analyzed rigid endoscopies of the trachea in children to determine the incidence and characteristics of TB. Methods:In total, 1021 rigid endoscopies of the trachea recorded from children aged 0 to 6 years were analyzed. Endoscopic examination was performed from supraglottic region to carina using a 0-degree Hopkins rod-lens telescope. Patients with a TB were identified and the site of origin of the TB and its level above the carina was noted. Data of the identified patients was reviewed for the presence of preoperative airway findings such as stridor, upper lobe pneumonia and wheezing or atelectasis, other congenital anomalies, and intraoperative complications. Results:TB was detected in 11 (1.06%) of 1021 upper airway endoscopic examinations. All originated from the right lateral wall of the trachea. Six children had retained secretions in the TB, and 3 children had perioperative airway problems unrelated to the TB. One child showed right main stem bronchus narrowing as seen at the true carina, in the presence of a TB. All the children with TB exhibited at least 1 additional congenital anomaly at birth besides TB. Conclusions:TB is a relatively common congenital endoscopic lower airway anomaly in childhood, which is itself rarely symptomatic, but almost always coexists with other congenital anomalies.

Prevalence and characteristics of tracheal cobblestoning in children

Tracheal follicular pattern or so‐called tracheal cobblestoning is a poorly described entity in the literature and is depicted as a nodular or lumpy appearance of the tracheal wall mucosa suggesting tracheal irritation from factors like gastro‐esophageal reflux (GERD) or pulmonary infection. The aim of the present study was to investigate the prevalence and characteristics of tracheal cobblestones in a large pediatric population.

Management of laryngomalacia in children with congenital syndrome: The role of supraglottoplasty

BACKGROUND/IMPORTANCE Supraglottoplasty is the surgical procedure of choice for severe laryngomalacia and has shown to be successful in most cases; however, patients with medical comorbidities present a higher rate of failure. To date, the best management of laryngomalacia in children with congenital syndrome remains unclear. PURPOSE To study the outcome of supraglottoplasty in children with severe laryngomalacia, and to analyze the management and outcome in infants with a congenital syndrome. METHODS Retrospective medical records review from January 2003 to October 2012 of all patients who underwent laser supraglottoplasty for severe laryngomalacia at the University Childrens Hospital Zurich, Switzerland. RESULTS Thirty-one patients were included; median age at time of surgery was 3.5 months. Three patients (10%) had a genetically proven congenital syndrome with associated neurologic anomalies. Overall success rate was 87%. Failures were observed in four (13%) of 31 cases; including all three patients presenting a congenital syndrome. CONCLUSIONS Supraglottoplasty is an effective and safe treatment for laryngomalacia in otherwise healthy children. Signs of a possible underlying predominant neurologic origin and discrepancy between the clinical presentation and the endoscopic findings have to be taken into account, as in children with congenital syndrome with neurologic anomalies the risk of failure is higher.