Danish guidelines on management of otitis media in preschool children.

INTRODUCTION: Otitis media is one of the most common diseases in small children. This underlines the importance of optimizing diagnostics and treatment of the condition. Recent literature points toward a stricter approach to diagnosing acute otitis media (AOM). Moreover, ventilating tube treatment for recurrent AOM (RAOM) and chronic otitis media with effusion (COME) has become the most frequently performed surgical procedure in pre-school children. Therefore, the Danish Health and Medicines Authority and the Danish Society of Otorhinolaryngology, Head and Neck Surgery deemed it necessary to update the Danish guidelines regarding the diagnostic criteria for acute otitis media and surgical treatment of RAOM and COME. METHODS: The GRADE system (The Grading of Recommendations Assessment, Development and Evaluation) was used in order to comply with current standards of evidence assessment in formulation of recommendations. An extensive literature search was conducted between July and December 2014. The quality of the existing literature was assessed using AGREE II (Appraisal of Guidelines for Research & Evaluation), AMSTAR (assessing the Methodological Quality of Systematic Reviews), QUADAS-2 (Quality of Diagnostic Accuracy Studies), Cochrane Risk of Bias Tool for randomized trials and ACROBAT-NRSI (A Cochrane Risk of Bias Assessment Tool for Non-Randomized Studies). The working group consisted of otolaryngologists, general practitioners, pediatricians, microbiologists and epidemiologists. CONCLUSION: Recommendations for AOM diagnosis, surgical management for RAOM and COME, including the role of adenoidectomy and treatment of ventilating tube otorrhea, are proposed in the guideline.

Induction of mucin and adhesion molecules in middle ear mucosa.

We hypothesized that inflammation molecules induce the secretory hyperplasia characteristic of otitis media with effusion (OME). The purpose of the present study was to compare the location of inflammation molecules and mucin in the middle ear mucosa of both normal and OME ears. OME was created by bisection of the tensor veli palatini muscle in germ-free rabbits, and the development of middle ear effusion was confirmed by otomicroscopy and tympanometry. Ventilation tubes (VTs) were inserted in half of the ears. The animals were decapitated after 8 weeks, and serial sections of the middle ear mucosae were either periodic acid-Schiff (PAS)-stained or stained immunohistochemically for inflammation molecules or mucins. The length of stained epithelium was measured and related to the total epithelial length. There was a striking resemblance between mucin-type MUC5B- and PAS-positive epithelium and areas positive for the chemoattractant inflammation molecules intercellular adhesion molecule-1 (ICAM-1) and RANTES (reacted upon activation, normal T expressed and secreted). The percentages of ICAM-1- and PAS-stained epithelium were significantly higher in OME ears than in normal ears. OME ears treated with VTs also contained significantly more PAS-positive epithelium than normal ears, but less than OME ears. Based on the spatial and temporal coincidence between ICAM-1 and mucin, it is suggested that: (i) inflammation may initiate and maintain the hypersecretory state of the middle ear mucosa which is presumably responsible for the chronicity of OME; and (ii) that MUC5B is a major mucin component of OME effusions.

RANTES in otitis media with effusion: presence, role and correlation with cytokines and microbiology.

Various inflammatory cells and cytokines have been identified in otitis media with effusion (OME). The presence of neutrophils has been linked to interleukin-8, but no chemotactic factor has as yet been identified for monocytes. The chemokine RANTES (Regulated upon Activation, Normal T Expressed and Secreted) attracts and activates primarily monocytes and may contribute to the pathogenesis of middle ear inflammation. We investigated the presence of RANTES by: 1) ELISA measurement in 114 middle ear effusions from children suffering from OME, 2) immunohistochemical localisation in experimental OME rabbit middle ear mucosa, and 3) expression in cultured rabbit middle ear epithelium in response to proinflammatory stimuli. RANTES was detectable in 94 (82%) of 114 effusions with a median concentration of 79.7 pg/mg total protein content. The concentration of RANTES was positively correlated with the endotoxin content. Immunohistochemically, RANTES was localized to the epithelial layer in experimental OME. In vitro, RANTES was expressed in middle ear epithelium in response to proinflammatory stimuli (TNF-alpha) in a dose-dependent manner. The expression of RANTES may explain the recruitment of monocytes in OME, possibly as a result of TNF-alpha-mediated endotoxin stimulation.

[Ambulatory mediastinoscopy]. / Dagkirurgisk mediastinoskopi.

INTRODUCTION: The present study was undertaken to investigate the safety of mediastinoscopy as a routine outpatient procedure. METHODS: We reviewed the first 108 mediastinoscopies performed at our outpatient surgery centre. RESULTS: During the period, 1996 to 1999, 108 out of 206 (52%) mediastinoscopy patients were admitted to the outpatient surgery centre, and 86 (80%) of these were discharged the same day. These numbers were 86% and 86% for 1999 alone, which reflects acceptance of outpatient surgery. One patient was admitted because of preoperative mediastinal venous bleeding, which required compression for 24 hours, and 19 more patients were admitted without strict medical indications. Two patients were admitted later the same day after discharge, because of minor wound bleeding, which was stopped by infiltration with adrenalin. DISCUSSION: Mediastinoscopy can be performed safely as an outpatient procedure on most patients.

How does endotoxin trigger inflammation in otitis media with effusion?

OBJECTIVES: The relationship among microorganisms, endotoxin, and inflammatory mediators in otitis media with effusion (OME) was examined. STUDY DESIGN: Analysis of 152 middle ear effusions aspirated at the time of ventilation tube insertion from children with OME. METHODS: Effusion samples were cultured for pathogenic bacteria The two primary cytokines, interleukin-1beta (IL1beta) and tumor necrosis factor (TNFalpha), and the adhesion molecules, intercellular and vascular adhesion molecule (ICAM-1 and VCAM-1), were quantified using the enzyme-linked immunosorbent assay (ELISA) technique. Endotoxin concentration was measured with a limulus amebocyte lysate assay, and total protein concentration was quantified using the Biorad microassay. RESULTS: The cultures of pathogenic bacteria were positive in 33 of the 152 effusions (22%), which contained more endotoxin and more of the primary cytokines than the 119 culture-negative effusions. Endotoxin and the primary cytokines were positively correlated, both in the whole material and in the sterile effusions alone. The adhesion molecules were positively correlated with each other, but not with endotoxin or the primary cytokines. CONCLUSIONS: We found a positive correlation between endotoxin and the primary cytokines TNFalpha and IL1beta in culture-positive OME effusions as well as in culture-negative ones, suggesting endotoxin-induced local production of TNFalpha and IL1beta in the middle ear. ICAM-1 and VCAM-1 were also present in the middle ear, but their concentrations were not directly correlated to endotoxin or the primary cytokines.

Effect of N-acetylcysteine on the incidence of recurrence of otitis media with effusion and re-insertion of ventilation tubes.

Previous studies have demonstrated the anti-inflammatory, anti-oxidant, and mucolytic nature of N-acetylcysteine (NAC). Theoretically, these properties make the substance ideal for therapeutic use against otitis media with effusion (OME). The disease is characterized as a sustained non-specific inflammation of the middle ear mucosa with secretory transformation of the epithelium resulting in accumulation of fluid in the middle ear space. To investigate the effects of instillation of NAC in the middle ear, a double-blind, placebo-controlled, randomized trial was carried out. A total of 75 children who were undergoing their first bilateral insertion of ventilation tubes (VT) due to OME were randomized to Mucomyst (NAC) or placebo (the vehicle) on one ear in relation to the VT insertion. The contralateral ear underwent VT insertion exclusively. Instillation of Mucomyst or placebo was repeated 3 and 7 days afterwards. The children were followed regularly for 11-39 months. Episodes of otorrhea, recurrence of OME after VT extrusion and re-insertion of VTs were registered as primary outcome parameters. The results demonstrated that Mucomyst significantly reduced the recurrence of OME and re-insertion of VTs (p < 0.025) and significantly increased the time until VT extrusion (p < 0.0167). In addition, the number of episodes of ear problems and visits at the ENT clinic were reduced significantly by NAC (p < 0.0383).

Middle ear epithelium has inflammatory capacity.

Endotoxin, tumour necrosis factor-alpha (TNF-alpha), interleukin-1 beta (IL-1 beta) and intercellular adhesion molecule-1 (ICAM-1) were detected in 88%, 51%, 58% and 66% of 152 middle ears from patients suffering from otitis media with effusion. In this study the hypothesis that bacterial endotoxin, TNF-alpha, IL-1 beta and ICAM-1 induce the inflammatory process characteristic of otitis media with effusion was tested. Cultures of rabbit middle ear epithelium were exposed to endotoxin, TNF-alpha or IL-1 beta. The expression of ICAM-1 on the cell surfaces was measured with a direct enzyme-linked immunosorbent assay on the cell layer. For TNF-alpha, 5 ng/ml significantly increased ICAM-1 expression, whereas 100 ng/ml had a toxic effect. For IL-1 beta, as little as 1 ng/ml produced a significant increase in ICAM-1 expression. Endotoxin stimulated ICAM-1 expression less strongly in concentrations from 100 ng/ml to 100 micrograms/ml. The findings indicate that stimulation of ICAM-1 by endotoxin is mediated, at least in part, by TNF-alpha and IL-1 beta. It is concluded that endotoxin induces sustained inflammation in OME, and that this inflammation is mediated, at least in part, by the primary cytokines TNF-alpha and IL-1 beta.

[Correct documentation of drug prescriptions]. / Ordentlige medicinoptegnelser.

The present study was undertaken to investigate and minimize possible differences in doctors' and nurses' documentation of drug prescriptions. A retrospective medical audit including 100 patients receiving medication revealed 69% correct prescriptions in doctors' case records. Only 44% of prescriptions in nurses' drug lists were correct. Based on the exposed problems a prescription sheet and clinical guidelines for medication were developed and implemented in the department. This resulted in 91% correct prescriptions in a comparable group of 100 patients receiving medication, a highly significant improvement. Among prescriptions signed by a doctor as legally requested, 98% were correct. The prescription sheet also served as an updated survey of medication. No health-threatening prescription errors were disclosed in either group. In conclusion, a common prescription sheet significantly improved the quality of drug prescriptions.

Influence of hyperoxia on in vitro growth of rabbit middle ear epithelium and auditory meatal epithelium.

The oxygen partial pressure of middle ear gas increases more than 3-fold upon insertion of ventilation tubes, while the carbon dioxide partial pressure decreases. Whereas the middle ear gas is normally equilibrated to venous gases and has an oxygen partial pressure of 43 mmHg, 138 mmHg is measured in ventilated ears. The present study was undertaken to compare the effects of these oxygen tensions on in vitro growth and glycoprotein secretion of rabbit middle ear epithelium and for comparison auditory meatal epithelium. Cultures were incubated in atmospheres of 7, 21 or 75% O2 in 5% CO2 and the remnant N2. The cell layer protein mass, [3H]thymidine-incorporation, DNA content and [3H]glucosamine-incorporation was measured in identical subcultures every third day during a 15-day period. In middle ear epithelium the DNA content, DNA synthesis and cell layer protein mass were significantly higher at 7% oxygen compared to 21% and 75%. In conclusion hyperoxia leads to decreased growth of middle ear epithelium in vitro. If applicable to in vivo conditions, this might contribute to the mechanism of action of ventilation tubes. Moreover the proliferation rate of auditory meatal epithelium exceeds that of middle ear epithelium both at 7 and 21% oxygen, an interesting point with regards to cholesteatoma pathogenesis.

Quantification of in vitro growth and synthesis in rabbit middle ear epithelial cells.

The purpose of the present study was a quantitative description of middle ear epithelial cell reactions in a standardized model system under controlled conditions. The model is based on a newly developed culture method for rabbit middle ear epithelial cells. The growth pattern of identical subcultures was determined by measurement of total cell protein, DNA synthesis and DNA amount during a 15-day period. The secretory product was quantified by means of 3H-glucosamine incorporation. Epithelial cells from the auditory meatus were examined by identical methods. The results proved the method to be reproducible regarding all parameters. The DNA amount and total cell protein increased throughout the period, whereas DNA synthesis remained constant. Secretion increased linearly for 9 days and then diminished. All parameters were without significant changes when related to DNA amount, reflecting a uniform cellular activity throughout the period. The DNA amount was the most precise parameter with a mean variation coefficient of 6.0% (SD 3.1%). With the baseline values found to be reproducible for the parameters chosen, our model system is considered to be usable for quantifying various factors influencing the proliferation and activity of middle ear epithelium.

Culture of rabbit middle ear epithelial cells. A method for primary culture and subculture with identification, characterization and growth specification.

During the last decade middle ear epithelium has been cultured from various species. Until now, subcultivation has been achieved only with the use of a feeder-cell layer or conditioned medium. These factors are possible confounders in the in vitro model. On the other hand, subcultivation is necessary for exact quantitative studies. We present a reproducible culture method allowing subcultivation without feeder-cells or conditioned medium. The main features in our method are a low-serum, hormone-supplemented medium, an incubation temperature of 34 degrees C, fixation of explants, gentle trypsinization and replating with high cell density. Cells were identified by immunohistochemistry through a battery of monclonal antibodies. The percentage of epithelial cells in the subculture was 99.2%. To our knowledge, this is the first report describing subcultivation of middle ear epithelial cells exclusively in a completely controlled environment. These are optimal circumstances for future investigation and quantification of various factors influencing proliferation and differentiation of middle ear epithelium.