Association Between Age and Weight as Risk Factors for Complication After Tonsillectomy in Healthy Children.

Importance: The 1996 Tonsillectomy and Adenoidectomy Inpatient Guidelines of the American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS) Pediatric Otolaryngology Committee recommended that children younger than 3 years be admitted following tonsillectomy. Recommendations for hospital observation were not included as a key action statement in the 2011 AAO-HNS Clinical Practice Guidelines for Tonsillectomy in Children. Objective: To examine the association between posttonsillectomy complication rate and the age and weight of the child at the time of surgery. Design, Setting, and Participants: This was a multicenter case series study with medical record review of 2139 consecutive children ages 3 to 6 years who underwent tonsillectomy at 1 tertiary care academic center and 5 acute care centers in New Orleans, Louisiana, between 2005 and 2015. Children with moderate to severe developmental delay, bleeding disorders, and other major medical comorbidities were excluded. Main Outcomes and Measures: Complications examined included respiratory distress, dehydration requiring intravenous fluids, and bleeding. Results: Of the 2139 patients, 1817 met inclusion criteria. A total of 1011 (55.6%) were male. The mean (SD) age at the time of the procedure was 46 (14) months (range, 12-72 months). The mean weight at the time of the procedure was 17 (5) kg (range, 9-43 kg). A total of 95 patients (5.2%) had a postoperative complication. Of the 455 children younger than 3 years in the study, 32 (7.0%) had complications compared with 63 (4.6%) of the 1362 patients 3 years or older. The odds of having a complication in children younger than 3 years was 1.5 times greater than it was in children 3 years or older (odds ratio [OR], 1.56; 95% CI, 1.00-2.42). When examining total complications, children younger than 3 years were more likely to experience a complication within the first 24 hours after surgery than children 3 years or older (25% vs 9.5%; OR, 3.17; 95% CI, 1.00-10.11). The children admitted to the hospital had a greater risk of complication than those treated as an outpatient, independent of age (6.9% vs 93.0%; OR, 3.49; 95% CI, 2.0.18-6.05). No association between weight and complications was found on logistic regression (area under the curve = 0.5268; P = .66). Conclusions and Relevance: Healthy children younger than 3 years may be at an increased risk for complication following tonsillectomy. Those children may also be at increased risk for complications within the first 24 hours after surgery compared with children 3 years or older. Our data suggest that complications are independent of weight in these patients. In our cohort, those patients selected for overnight observation were associated with an increased number of adverse events following tonsillectomy, suggesting that clinician judgment is crucial in determining which patients are safe for outpatient tonsillectomy.

Adenotonsillectomy for Obstructive Sleep Apnea and Quality of Life: Systematic Review and Meta-analysis.

Objective To determine the impact of adenotonsillectomy on the quality of life of pediatric patients with obstructive sleep apnea (OSA) and to identify gaps in the current research. Data Sources The MEDLINE, EMBASE, and Cochrane databases were systematically searched via the Ovid portal on June 18, 2016, for English-language articles. Review Methods Full-text articles were selected that studied boys and girls <18 years of age who underwent adenotonsillectomy for OSA or sleep-disordered breathing and that recorded validated, quantitative quality-of-life outcomes. Studies that lacked such measures, performed adenotonsillectomy for indications other than OSA or sleep-disordered breathing, or grouped adenotonsillectomy with other procedures were excluded. Results Of the 328 articles initially identified, 37 were included for qualitative analysis. The level of evidence was generally low. All studies involving short-term follow-up (≤6 months) showed improvement in quality-of-life scores after adenotonsillectomy as compared with preoperative values. Studies involving long-term follow-up (>6 months) showed mixed results. Modifications to and concurrent procedures with conventional adenotonsillectomy were also identified that showed quality-of-life improvements. Three studies were identified for meta-analysis that compared pre- and postoperative Obstructive Sleep Apnea-18 scores. Short- and long-term follow-up versus preoperative scores showed significant improvement ( P < .001). Short- and long-term scores showed no significant difference. Conclusion This systematic review and meta-analysis demonstrate adenotonsillectomy's effectiveness in improving the quality of life of pediatric patients with OSA. This is well demonstrated in the short term and has strong indications in the long term.

Utility of polysomnography in determination of laryngomalacia severity.

OBJECTIVE: To examine the efficacy of polysomnography in determining the severity of laryngomalacia in pediatric patients. METHODS: Prospective cohort study. Pediatric patients referred to our pediatric otolaryngology department with a polysomnogram already performed for a presumptive diagnosis of laryngomalacia were enrolled in the study. Patients with concurrent airway lesions or neuromuscular disorders were excluded. Patients underwent history, physical exam, and flexible fiberoptic laryngoscopy. These results were used to calculate a total laryngomalacia severity score. RESULTS: 25 pediatric patients (n = 25) with an average age of 3.9 months at time of initial evaluation met criteria for enrollment in our study. 100% of patients had obstructive sleep apnea by definition. 80% of these patients underwent supraglottoplasty. The average AHI of those who underwent surgery (57.26) was not significantly different in those who underwent surgery vs. those that did not (55.43) (p = 0.41). In comparison, the average laryngomalacia severity score based from history, physical exam and flexible laryngoscopy was significantly greater in the patients that required supraglottoplasty (11.16) vs. those who did not (5.33) (p = 0.03). In addition a higher laryngomalacia severity score was not correlated with a higher AHI (p = 0.81, r = 0.08, CI: -0.5197 to 0.6235). CONCLUSION: In our cohort, polysomnography was not useful in determining the severity of laryngomalacia, did not correlate with the clinical evaluation, and alone was not predictive of the patients that would require surgical intervention. History, physical exam, and endoscopic findings remain reliable predictors of disease severity and need for operative intervention.

A newborn with three cochlear turns: Case report and literature review.

Objectives/Hypothesis: The human cochlea is most commonly considered to have two and a half turns. Although the causes of cochlear hypoplasia are well described, cochlear hyperplasia is a rarer entity that is poorly understood. We describe rare anatomic cochlear malformations identified in a 4-month-old male originally referred for evaluation after a failed newborn hearing screening. The full diagnostic evaluation, imaging findings, treatment, and follow-up are described in detail. Cochleae with three turns are an uncommon malformation that is not included in current classifications schemes and may represent a distinct type of anomaly not caused by developmental arrest.

Lund-mackay staging system in cystic fibrosis: a prognostic factor for revision surgery?

BACKGROUND: Cystic fibrosis (CF) is an autosomal recessive genetic disease that affects approximately 30,000 people in the United States. Mucus in CF patients can be exceptionally viscous, leading to progressive cycles of inflammation and infection. The most widely accepted staging system used to score sinus computed tomography (CT) scans is the Lund-Mackay Score (LMS). METHODS: To determine if a significant correlation exists between LMS and the need for revision sinus surgery in a patient population with CF, we performed a retrospective review of 32 patients with CF who were referred to the Tulane Otolaryngology Clinic from 2005 to 2011 and received a CT scan of the paranasal sinuses. CT scans were graded in a blinded manner by the institution's neuroradiologist using the LMS system. RESULTS: We found no statistically significant difference in the raw or scaled LMSs between patients receiving revision surgery (n=9) and patients receiving a single surgery (n=23). CONCLUSIONS: CT scans are vital for preoperative planning, but they are not a useful tool for risk stratification. More specifically, application of the LMS is not relevant in identifying which CF patients with chronic rhinosinusitis will be at risk for revision surgeries.

Retropharyngeal phlegmon in Rosai Dorfman disease.

Rosai Dorfman disease (RD), also known as sinus histiocytosis with massive lymphadenopathy (SHML), is a benign histiocytic proliferative condition of unsubstantiated etiology that most often presents as bilateral painless cervical lymphadenopathy. Head and neck manifestations of RD are diverse but most commonly present as massive cervical lymphadenopathy. Interestingly, a retropharyngeal fluid collection has never been described as a sequelae of RD. Our objective is to present a novel case of a 9-year old female with RD that suffered from recurrent retropharyngeal phlegmon and to discuss diagnostic and treatment recommendations for this disease process.

An unusual presentation of Gaucher disease in an infant with progressive dyspnea.

BACKGROUND: The most common lysosomal storage disorder, Gaucher disease, represents a collection of 3 clinical syndromes associated with disrupted glucocerebroside catabolism. Despite the common occurrence of dyspnea in advanced Gaucher, dyspnea is rarely reported as a presenting symptom of the disease. CASE REPORT: A 10-month-old male was referred to the Otolaryngology Clinic for evaluation of progressive dyspnea. Physical examination was significant for cervical adenopathy, inspiratory stridor, and developmental delay. A complete evaluation for failure to thrive and lymphadenopathy was performed, with subsequent lymph node biopsy and enzyme assay confirming the presence of Gaucher disease. CONCLUSION: A high level of suspicion is required to make an early diagnosis of Gaucher disease, but it should be considered in patients presenting with failure to thrive, generalized lymphadenopathy, and respiratory or neurologic findings. Initiation of early treatment is paramount for the prevention of irreversible disease.

Obstructive lesions of the pediatric subglottis.

PURPOSE: To compile information regarding obstructive subglottic lesions in children, including anatomy, pathogenesis, prevention, evaluation, and treatment options, required for implementation of a multi-faceted treatment plan. METHOD: Review of the literature. CONCLUSIONS: Although they are infrequent, obstructive subglottic lesions pose significant challenges to treating physicians, from airway management and injury prevention to decannulation and voice rehabilitation. Most patients with these lesions require multidisciplinary care and long-term treatment and can nearly always be treated successfully.

Pleomorphic adenoma of the parotid gland in children.

OBJECTIVE: To evaluate the presentation, imaging characteristics and treatment outcome of pleomorphic adenoma of the parotid in the pediatric population. DESIGN: Retrospective study with institutional review board approval. SETTING: Tertiary care pediatric medical center. METHODS: An extensive review of medical records with regard to presentation, imaging, histopathology, complication, recurrence and prognosis on patients 18 years or younger presenting from 1983 to 2005. RESULTS: Eleven patients (six females, five males) were identified. The most common presentation was an asymptomatic mass. Preoperative imaging was done on nine patients: MRI (N=6), CT (N=3), ultrasound (N=2), and sialogram (N=1). Initial treatments included: superficial parotidectomy (N=5), total parotidectomy (N=3), excisional biopsy followed by superficial parotidectomy (N=2), and excisional biopsy (N=1). There were two recurrences (18%); one presenting 7 months following excisional biopsy who underwent superficial parotidectomy and one occurred 3 years following total parotidectomy requiring revision parotidectomy and radiation. Other complications included: transient facial nerve paresis (N=5; 45%) and permanent weakness (N=1; 9%). The patients were followed an average of 18 months. CONCLUSIONS: Pleomorphic adenoma is one of the most common tumors of the parotid in children. The most common presentation is an asymptomatic mass. A preoperative evaluation with MRI or CT scan can be helpful in determining the extent of the lesion and surgical planning. Complete excision via superficial or total parotidectomy with preservation of facial nerve is the treatment of choice. Long-term follow up is recommended, though was difficult in a tertiary care center.

Reliability of the pharyngeal squeeze maneuver.

OBJECTIVES: Fiberoptic endoscopic evaluation of swallowing with sensory testing has been used to assess the integrity of laryngopharyngeal sensory and motor components. The pharyngeal squeeze is a maneuver used during fiberoptic endoscopic evaluation of swallowing with sensory testing to assess pharyngeal motor function. Although the pharyngeal squeeze manuever has been used in numerous scientific publications, its reliability has not been critically evaluated. Therefore, we sought to evaluate the reliability of the pharyngeal squeeze maneuver. METHODS: Forty individuals who were undergoing fiberoptic laryngoscopy for various reasons were instructed to perform the pharyngeal squeeze maneuver. Three different clinicians reviewed the videotape on 4 separate occasions. The clinicians were first asked to rate each side of the pharynx as normal, diminished, or absent. They were then instructed to simply rate the maneuver as normal or abnormal. The interobserver and intraobserver reliability of the pharyngeal squeeze maneuver were assessed with the kappa coefficient. RESULTS: The mean age of the cohort was 58 years. Fifty-eight percent (23 of 40) were male. When the clinicians were instructed to rate each side of the pharynx as normal, diminished, or absent, the interobserver and intraobserver reliabilities were poor (63% to 68% agreement; kappa = 0.18 to 0.67). When the clinicians were asked to rate the pharyngeal squeeze maneuver as normal or abnormal, both interobserver and intraobserver reliabilities were excellent (85% to 98% agreement; kappa = 0.75 to 0.95). CONCLUSIONS: The pharyngeal squeeze maneuver displayed poor reliability when motor function was classified into unilateral or bilateral normal, diminished, and absent categories. The pharyngeal squeeze maneuver was very reliable when simply graded as normal or abnormal. Clinicians could not reliably distinguish between diminished and absent pharyngeal motor functions.

Evidence for a rolling-circle mechanism of phage DNA synthesis from both replicative and integrated forms of CTXphi.

The genes encoding cholera toxin, the principal virulence factor of Vibrio cholerae, are part of the circular single-stranded DNA genome of CTXphi. In toxigenic V. cholerae strains, the CTXphi genome is typically found in integrated arrays of tandemly arranged CTX prophages. Infected cells that lack a chromosomal integration site harbour the CTXphi genome as a plasmid (pCTX). We studied the replication of pCTX and found several indications that this plasmid replicates via a rolling-circle (RC) mechanism. The initiation and termination sites for pCTX plus-strand DNA synthesis were mapped to a 22 bp sequence that contains inverted repeats and a nonanucleotide motif found in the plus-strand origins of several RC replicons. Furthermore, similar to other RC replicons, replication of plasmids containing duplicated pCTX origins resulted in the deletion of sequences between the two origins and the formation of a single chimeric origin. Our previous work revealed that CTX prophage arrays give rise to hybrid CTX virions that contain sequences derived from two adjacent prophages. We now report that the boundaries between the sequences contributed to virions by the upstream and the downstream prophages in an array correspond to the site at which synthesis of plus-strand pCTX DNA is initiated and terminated. These data support the model that plus-strand CTXphi DNA is generated from chromosomal prophages via a novel process analogous to RC replication.

The Vibrio cholerae O139 Calcutta bacteriophage CTXphi is infectious and encodes a novel repressor.

CTXphi is a lysogenic, filamentous bacteriophage. Its genome includes the genes encoding cholera toxin (ctxAB), one of the principal virulence factors of Vibrio cholerae; consequently, nonpathogenic strains of V. cholerae can be converted into toxigenic strains by CTXphi infection. O139 Calcutta strains of V. cholerae, which were linked to cholera outbreaks in Calcutta, India, in 1996, are novel pathogenic strains that carry two distinct CTX prophages integrated in tandem: CTX(ET), the prophage previously characterized within El Tor strains, and a new CTX Calcutta prophage (CTX(calc)). We found that the CTX(calc) prophage gives rise to infectious virions; thus, CTX(ET)phi is no longer the only known vector for transmission of ctxAB. The most functionally significant differences between the nucleotide sequences of CTX(calc)phi and CTX(ET)phi are located within the phages' repressor genes (rstR(calc) and rstR(ET), respectively) and their RstR operators. RstR(calc) is a novel, allele-specific repressor that regulates replication of CTX(calc)phi by inhibiting the activity of the rstA(calc) promoter. RstR(calc) has no inhibitory effect upon the classical and El Tor rstA promoters, which are instead regulated by their cognate RstRs. Consequently, production of RstR(calc) renders a CTX(calc) lysogen immune to superinfection by CTX(calc)phi but susceptible (heteroimmune) to infection by CTX(ET)phi. Analysis of the prophage arrays generated by sequentially integrated CTX phages revealed that pathogenic V. cholerae O139 Calcutta probably arose via infection of an O139 CTX(ET)phi lysogen by CTX(calc)phi.

Preprotein transfer to the Escherichia coli translocase requires the co-operative binding of SecB and the signal sequence to SecA.

In Escherichia coli, precursor proteins are targeted to the membrane-bound translocase by the cytosolic chaperone SecB. SecB binds to the extreme carboxy-terminus of the SecA ATPase translocase subunit, and this interaction is promoted by preproteins. The mutant SecB proteins, L75Q and E77K, which interfere with preprotein translocation in vivo, are unable to stimulate in vitro translocation. Both mutants bind proOmpA but fail to support the SecA-dependent membrane binding of proOmpA because of a marked reduction in their binding affinities for SecA. The stimulatory effect of preproteins on the interaction between SecB and SecA exclusively involves the signal sequence domain of the preprotein, as it can be mimicked by a synthetic signal peptide and is not observed with a mutant preprotein (delta8proOmpA) bearing a non-functional signal sequence. Delta8proOmpA is not translocated across wild-type membranes, but the translocation defect is suppressed in inner membrane vesicles derived from a prIA4 strain. SecB reduces the translocation of delta8proOmpA into these vesicles and almost completely prevents translocation when, in addition, the SecB binding site on SecA is removed. These data demonstrate that efficient targeting of preproteins by SecB requires both a functional signal sequence and a SecB binding domain on SecA. It is concluded that the SecB-SecA interaction is needed to dissociate the mature preprotein domain from SecB and that binding of the signal sequence domain to SecA is required to ensure efficient transfer of the preprotein to the translocase.

Vibrio cholerae hemagglutinin/protease inactivates CTXphi.

Pathogenic strains of Vibrio cholerae are lysogens of the filamentous phage CTXphi, which carries the genes for cholera toxin (ctxAB). We found that the titers of infective CTXphi in culture supernatants of El Tor CTXphi lysogens increased rapidly during exponential growth but dropped to undetectable levels late in stationary-phase growth. When CTXphi transducing particles were mixed with stationary-phase culture supernatants of El Tor strains, CTXphi infectivity was destroyed. Our data indicate that this growth phase-regulated factor, designated CDF (CTXphi-destroying factor), is the secreted hemagglutinin/protease (HA/P) of V. cholerae. A strain containing a disrupted hap gene, which encodes HA/P of V. cholerae, did not produce CDF activity in culture supernatants. Introduction of the HA/P-expressing plasmid pCH2 restored CDF activity. Also, CDF activity in culture supernatants of a variety of pathogenic V. cholerae isolates varied widely but correlated with the levels of secreted HA/P, as measured by immunoblotting with anti-HA/P antibody. CDF was purified from V. cholerae culture supernatants and shown to contain a 45-kDa polypeptide which bound anti-HA/P antibodies and which comigrated with HA/P in sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The production of high levels of secreted HA/P by certain V. cholerae strains may be a factor in preventing CTXphi reinfection in natural environments and in the human host.

CTXphi immunity: application in the development of cholera vaccines.

CTXphi is a filamentous bacteriophage that encodes cholera toxin, the principal virulence factor of Vibrio cholerae. CTXphi is unusual among filamentous phages because it encodes a repressor and forms lysogens. CTXphi can infect the existing live-attenuated V. cholerae vaccine strains derived from either the El Tor or classical V. cholerae biotypes and result in vaccine reversion to toxinogenicity. Intraintestinal CTXphi transduction assays were used to demonstrate that El Tor biotype strains of V. cholerae are immune to infection with the El Tor-derived CTXphi, whereas classical strains are not. The El Tor CTXphi repressor, RstR, was sufficient to render classical strains immune to infection with the El Tor CTXphi. The DNA sequences of the classical and El Tor CTXphi repressors and their presumed cognate operators are highly diverged, whereas the sequences that surround this "immunity" region are nearly identical. Transcriptional fusion studies revealed that the El Tor RstR mediated repression of an El Tor rstA-lacZ fusion but did not repress a classical rstA-lacZ fusion. Likewise, the classical RstR only repressed a classical rstA-lacZ fusion. Thus, similar to the mechanistic basis for heteroimmunity among lambdoid phages, the specificity of CTXphi immunity is based on the divergence of the sequences of repressors and their operators. Expression of the El Tor rstR in either El Tor or classical live-attenuated V. cholerae vaccine strains effectively protected these vaccines from CTXphi infection. Introduction of rstR into V. cholerae vaccine strains should enhance their biosafety.

Regulation, replication, and integration functions of the Vibrio cholerae CTXphi are encoded by region RS2.

CTXphi is a filamentous phage that encodes cholera toxin, one of the principal virulence factors of Vibrio cholerae. CTXphi is unusual among filamentous phages because it can either replicate as a plasmid or integrate into the V. cholerae chromosome at a specific site. The CTXphi genome has two regions, the 'core' and RS2. Integrated CTXphi is frequently flanked by an element known as RS1 which is related to RS2. The nucleotide sequences of RS2 and RS1 were determined. These related elements contain three nearly identical open reading frames (ORFs), which in RS2 were designated rstR, rstA2 and rstB2. RS1 contains an additional ORF designated rstC. Functional analyses indicate that rstA2 is required for CTXphi replication and rstB2 is required for CTXphi integration. The amino terminus of RstR is similar to the amino termini of other phage-encoded repressors, and RstR represses the expression of rstA2. Although genes with related functions are clustered in the genome of CTXphi in a way similar to those for other filamentous phages, the CTXphi RS2-encoded gene products mediating replication, integration and repression appear to be novel.

Intercellular C-signaling in Myxococcus xanthus involves a branched signal transduction pathway.

C-factor, the product of the csgA gene, is a cell-surface associated short-range intercellular signaling protein in Myxococcus xanthus. C-factor is required for at least four responses during starvation-induced fruiting body morphogenesis: rippling, aggregation, sporulation, and full expression of the csgA gene, all of which fail in a csgA mutant. To analyze the C-factor signaling pathway, eight Tn5 lac insertion mutants that began but failed to complete fruiting body aggregation were characterized. Seven of the insertions identified genes whose products function in the csgA signaling pathway. The seven mutants were differentially deficient in the C-factor responses, and could be divided into two classes on the basis of those differences. On one hand, the four mutants in class I were deficient in rippling and aggregation, but sporulated and produced C-factor at wild-type levels. The Tn5 lac insertions in the class I mutants mapped to the frz locus, which encodes a signal transduction system that controls the frequency of single cell reversals. On the other hand, mutants carrying any of the three closely linked class II Tn5 lac insertions had deficiencies in all four C-factor responses. Because the sporulation defect in the class 11 mutants is cell autonomous, the data suggest that the primary defect in these mutants is an inability to respond to the C-factor signal. All the data can be explained by a model in which the first part of the C-factor signaling pathway is common to all four C-factor-dependent responses. The genes identified by the class 11 insertions would function in the common part. Downstream of class II, the pathway branches. One branch includes the frz genes and leads to aggregation and rippling; the second branch leads to sporulation and controls the level of csgA gene expression. This model was confirmed in epistasis tests with characterized frz mutations, a csgA null mutation, and a class II mutation.

Diverse effects of mutation on the activity of the Escherichia coli export chaperone SecB.

The Escherichia coli SecB protein binds newly synthesized precursor maltose-binding protein (preMBP) and promotes its rapid export from the cytoplasm. Site-directed mutagenesis of two regions of SecB was carried out to better understand factors governing the SecB.preMBP interaction. 30 aminoacyl substitution mutants were analyzed, revealing two distinct classes of secB mutants. Substitutions at the alternating positions Phe-74, Cys-76, Val-78, or Gln-80 reduced the ability of SecB to form stable complexes with preMBP, but caused only mild defects in the rate of MBP export from living cells. The pattern revealed by this class of mutants suggests that a primary binding site for preMBP is hydrophobic and contains beta-sheet secondary structure. In contrast, substitutions at Asp-20, Glu-24, Leu-75, or Glu-77 caused a severe slowing in the rate of MBP export but did not disrupt SecB.preMBP complex formation. These largely acidic residues may function to regulate the opening of a preprotein binding site, allowing both high affinity preprotein binding and rapid dissociation of SecB.preprotein complexes at the membrane translocation site.