Promotion of acellular dermal matrix resolution in vitro by matrix metalloproteinase-2.

OBJECTIVE: To determine whether acellular human dermis is degraded by matrix metalloproteinases (MMPs), a large class of matrix-degrading enzymes. METHODS: The degradation of acellular human dermis specimens was evaluated in vitro. Wild-type murine fibroblasts with a broad-spectrum MMP inhibitor, GM6001, and MMP-2-deficient fibroblasts were placed on the basement membrane and dermal surfaces of acellular human dermis. Matrix degradation and fibroblast infiltration into the matrix were assessed after a 20-day incubation period. RESULTS: The basement membrane thickness of the specimens cultured with wild-type fibroblasts was significantly less than that of specimens cultured with GM6001 (P<.001), and the infiltration of fibroblasts into the dermal surface was limited by the addition of GM6001 (P=.002). To determine whether MMP-2 was involved in this in vitro phenotype, MMP-2-deficient fibroblasts were assessed in comparison with wild-type fibroblasts. Wild-type fibroblasts degraded the basement membrane surface (P<.001) and infiltrated the dermal surface (P = .003) more efficiently than did MMP-2-deficient fibroblasts. CONCLUSIONS: The results from our in vitro experiments suggest that MMPs and specifically MMP-2 may play an important role in the resorption of acellular human dermis. Addition of MMP inhibitors to implanted dermal matrices may slow fibroblast infiltration and improve their longevity in vivo.

Use of the Pediatric Quality of Life Inventory to assess the health-related quality of life in children with recurrent respiratory papillomatosis.

OBJECTIVES: The objective of this study was to use the Pediatric Quality of Life Inventory (PedsQL), a 23-question modular instrument designed to measure the health-related quality of life (HRQOL) in children and adolescents, to compare the HRQOL in children with recurrent respiratory papillomatosis (RRP) with the HRQOLs reported for healthy children and children with other chronic medical conditions. METHODS: The PedsQL version 4.0 Generic Core Scales consist of 23 questions in 4 subscales (Physical, Emotional, Social, and School Functioning) for parent-proxy reporting on the HRQOL in children ages 2 to 4 years, parent reporting for children 5 to 18 years, and child self-reporting for ages 5 to 7 years (age-adjusted questions and rating scales) and 8 to 18 years. The questionnaires were administered in person or by telephone to 22 children with RRP and (or, for children 2 to 4 years of age) one parent recruited from a tertiary pediatric otolaryngology practice. The results were compared with validated norms for healthy children and scores for children whose parents reported a chronic medical condition. RESULTS: Compared with healthy controls, the children 5 to 18 years of age with RRP self-reported a significantly (p < .05) worse HRQOL as measured by the PedsQL Total Score, Psychosocial Health score (a combination of Emotional, Social, and School Functioning Scores), and Social Functioning and School Functioning scores. Self-reported scores for the children 5 to 18 years of age with RRP compared with children with other chronic illnesses followed the same trend, and the difference approached statistical significance (p = .05) for the School Functioning Subscale scores. The parent-proxy report (for children 2 to 18 years of age) scores for children with RRP were significantly lower (p < .0001) on every scale and in total compared with scores for healthy children. Compared with scores of children with other chronic medical conditions, the parent-proxy report scores were significantly lower for psychosocial health (p = .005) and school functioning (p < .0001). CONCLUSIONS: Children with RRP report a lower quality of life than do those who are healthy, and a quality of life similar to that of those who have other chronic medical problems. The parent reports also reflect a lower quality of life for children affected by this disease, as compared with healthy children. The PedsQL demonstrated a statistically significant low HRQOL in children with RRP; however, the clinical implications of this finding appear trivial. A distinct, disease-specific survey for RRP, if developed, would have enhanced responsiveness and sensitivity to change (due to the natural course of the disease and/or surgical treatments).

Voice quality of prepubescent children with quiescent recurrent respiratory papillomatosis.

OBJECTIVE: The purpose of this study was to assess the long-term impact of recurrent respiratory papillomatosis (RRP) and its treatment on voice quality in prepubescent children. STUDY DESIGN: Case-control study. METHODS: Prepubescent children with RRP in remission for at least 12 [according to MM section] months were asked to participate. Remission was documented by absence of papillomas on fiberoptic flexible laryngoscopy. An age- and sex-matched control was selected for each patient enrolled. Voice was evaluated using the voice-related quality of life (V-RQOL) questionnaire, perceptual evaluations of voice quality by speech-language pathologists using the GRBAS (grade of hoarseness, roughness, breathiness, asthenia, strain) scale, and acoustic analysis (fundamental frequency, maximal phonation time, and relative average perturbation) using the Visi-Pitch II 3300. RESULTS: Medical records of 84 patients were reviewed and 15 met study criteria. Five agreed to participate but one was excluded due to the presence of papillomas. The four study patients and four matched controls were between 9- and 11-years old. On the V-RQOL questionnaire, each control rated V-RQOL as normal (10/50) and the average patient group score was within the normal range (11.5/50). On perceptual evaluations, the patient's voices were more hoarse, breathy, and rough compared to controls'. Acoustic analysis showed that patients' voices had a lower average fundamental frequency (F(0)) (200 Hz compared to 243 Hz for controls) and a higher relative average perturbation (RAP) (1.10 compared to 0.77), although only one patient's voice actually had elevated RAP (2.89), which had a large impact on raising the average score for the patient group. The average maximal phonation times were similar for the two groups (7.8s for patients and 7.4s for controls) but lower than average normal scores reported in the literature. CONCLUSIONS: Although children with RRP do not perceive their voice quality to have a negative impact on V-RQOL, speech-language pathologist evaluations and acoustic measurements show objective differences between the voices of children with quiescent RRP and those of normal, healthy controls.

Multiple intraparenchymal parotid calculi: a case report and review of the literature.

We describe an unusual case of bilateral intraparenchymal parotid stones with unilateral parotitis in a 17-year-old boy. The patient went on to develop multiple parotid abscesses, which we treated with a superficial parotidectomy. To our knowledge, this is only the second report of intraparenchymal parotid stones in a pediatric patient.