The effect of passive smoking on the levels of matrix metalloproteinase 9 in nasal secretions of children.

BACKGROUND: Matrix metalloproteinase (MMP) 9 is a gelatinase associated with tissue remodeling. It is thought to play a part in the pathogenesis of allergy. Increased levels of MMP-9 have been shown to increase in the acute allergic response in the nose, lungs, and skin. Exposure to passive tobacco smoke is associated with an increase in sneezing, nasal blockage, and a decreased sense of smell. The aim of this study was to study the effect of passive smoking on the levels of MMP-9 in nasal secretions of children. METHODS: A prospective descriptive study was performed. Thirty-nine children aged between 7 and 16 years were enrolled in the study. They were selected based on attendance at the Otorhinolaryngology Outpatients Clinic with a primary complaint unrelated to the nose or paranasal sinuses. Children with allergic rhinitis, sinusitis, or a recent cold were excluded. The study was performed at a tertiary pediatric referral center. Exposure to passive smoking was determined by measuring the urinary cotinine to creatinine ratio. Nasal fluid was obtained by using a Rhino-Probe curette (Arlington Scientific, Inc., Springville, UT). The concentration of MMP-9 was determined by ELISA. MMP-9 activity was determined by gelatin zymography. Data were tabulated on Microsoft Excel (Microsoft Corp., Redmond, WA) and analyzed using SPSS (SPSS Inc., Chicago, IL). RESULTS: Using a cutoff urinary cotinine/creatinine ratio of 0.025 ng/mg, 15 children were found to be exposed to passive smoking. Both the MMP-9 concentration and the activity were significantly higher in nasal secretions of children exposed to passive smoking. There was a distinct difference between the two cohorts with regard to the level of enzyme activity per weight of protein. The lowest level of enzyme activity recorded in the "exposed" cohort was over twice that of the level in the "not exposed" cohort. CONCLUSION: MMP-9 activity and concentration is higher in nasal secretions of children exposed to passive smoking. This suggests that passive smoking might alter the inflammatory response within the nasal mucosa in a similar way to allergy.

Tracheostomy--a 10-year experience from a UK pediatric surgical center.

BACKGROUND/PURPOSE: Tracheostomy in the pediatric population is associated with significant morbidity and mortality compared to adult practice. This study highlights evolving experience from a UK children's hospital. PATIENTS AND METHODS: All children undergoing tracheostomy between 1995 and 2004 were identified. Indications, complications, and outcomes were evaluated. RESULTS: Complete case records were reviewed for 112 children (age range, newborn-18 years). Indications included congenital birth defects--craniofacial disorders, esophageal atresia, laryngeal cleft, cystic hygroma, vascular malformations. Acquired upper airway pathology (15.5%) and malacia (12.1%) were additional criteria. Tracheostomy was also required for long-term ventilation in patients with neuromuscular disorders (12.1%) or ventilator dependency (26.7 %). Fifty-eight (50%) tracheostomies were created in infants <1 year. One hundred and nine were elective procedures with only 7 (6%) for emergency airway management. Morbidity included wound problems (14, 14.4%), tube displacement or obstruction (14, 14.4%), tracheocutaneous fistula (6, 6.2%), and pneumothorax (4, 4.1%). There were no acute hemorrhagic complications. Two children died after accidental tube displacement/obstruction. CONCLUSION: Tracheostomy at this UK center is largely undertaken as an elective procedure. Children less than 1 year form an increasing patient group. Complications may be minimized by meticulous surgical technique and ensuring a comprehensive tracheostomy care program.

Nontuberculous mycobacterial adenitis: effectiveness of chemotherapy following incomplete excision.

BACKGROUND: Management of lymphadenopathy caused by nontuberculous mycobacteria (NTM) is primarily surgical. Where this cannot achieve sufficient clearance of infected nodes, chemotherapy is often given. AIM: This study compared results of surgery alone with surgery followed by chemotherapy in instances where there was incomplete surgical removal of diseased tissue. METHODS: Chemotherapy comprised azithromycin 10 mg/kg and rifabutin 6 mg/kg both given once daily for 6 mo. Ninety-eight children with NTM infection were seen in the period 1990-2004. Sixty-eight cases with adenopathy where "time to healing" (discharge stopped and inflammation settled) was known were available to compare response to treatment. RESULTS: The median (range) "time to healing" in weeks for 43 patients who had surgery alone was: incision and drainage (I&D)/curettage 6 (1-72) (n = 10); excision 3 (1-28) (n = 22); and from the last operation of multiple (repeat) surgery 3 (1-40) (n = 11). For 25 patients who required chemotherapy in addition to surgery, the median (range) "time to healing" in weeks was I&D/curettage 10 (1-40) (n = 17), excision 14 (8-20) (n = 2) and multiple surgery 29 (2-88) (n = 6). CONCLUSION: In children with adenitis due to NTM, where surgical resection is followed by continued discharge and inflammation, chemotherapy should be considered before further surgery is undertaken.

Paediatric acute epiglottitis: not a disappearing entity.

OBJECTIVE: Paediatric epiglottitis is a serious, potentially life-threatening condition. Since the widespread introduction of the Haemophilus influenzae type b (Hib) conjugate vaccine in the UK in October 1992, there has been a dramatic reduction in its incidence. Vaccine failure is rare. The purpose of this study is to examine the failure rate of H. influenzae type b vaccine as measured by the number of cases of Haemophilus epiglottitis in fully vaccinated children presenting to a tertiary paediatric centre. A secondary aim is to provide a retrospective review of all cases of epiglottitis over a 13-year period. METHODS: A retrospective case-note review identifying all cases of epiglottitis presenting to Alder Hey Hospital was undertaken covering the time period December 1987-January 2001. Details of patient age, sex, source of referral, clinical presentation, management and complications along with microbiological and serological findings were obtained. There were 21 males and 19 females. The mean age was 36 months (range 6-125 months). A provisional diagnosis was made on the basis of the clinical features, confirmed by direct laryngoscopy in all but two cases and further supported in 28 cases by a positive blood culture. Of the 40 children presenting with epiglottitis, eight (20%) presented after the introduction of the Hib conjugate vaccine. H. influenzae antibody titres were measured both in the acute and convalescent phases of illness by the central Haemophilus Reference Unit in Oxford. RESULTS: We present the clinical features, management and complications of 40 cases of acute epiglottitis. H. influenzae was isolated from blood cultures in 28 cases (70%). In 12 of these cases, H. influenzae type b was identified, seven prior to 1993 and five thereafter. Four of these five cases presenting after introduction of the Hib vaccine were known to have been fully vaccinated. One child had a history of prematurity and serum immunoglobulin estimation was abnormally low in another child. Acute Hib antibody titre was less than 1 microg/ml in two of the three cases in which this was available. CONCLUSION: Whilst the incidence of Haemophilus type b epiglottitis has significantly diminished, vaccine failure does occur. We discuss the current understanding of clinical and immunological risk factors for vaccine failure and the significance of the Hib antibody titre. Further evaluation of vaccine failure would be of benefit. The series that we present highlights the importance of considering acute epiglottitis in the differential diagnosis of the child presenting with acute upper airway obstruction. This is particularly relevant when in future there will be fewer doctors familiar with the symptoms and signs of the disease.