Impact of Reduced Acidic Earwax pH and Earwax-Determinant Genotypes in Acquired Middle Ear Cholesteatoma.

OBJECTIVE: The development of acquired middle ear cholesteatoma is associated with a single nucleotide polymorphism, 538G>A, in the human adenosine triphosphate-binding cassette transporter C11 (ABCC11) gene, which is a determinant of the earwax morphotype, such as wet- and dry-type earwax; however, the mechanism underlying this association is unclear. We focused on the earwax pH and aimed to elucidate the mechanism between ABCC11 genotypes and acquired middle ear cholesteatoma. STUDY DESIGN: Prospective observational study. SETTING: Single-center, academic hospital. METHODS: We recruited 40 patients with acquired middle ear cholesteatoma who underwent surgery and 115 controls with no history of middle ear cholesteatoma. We assessed the earwax pH and ABCC11 genotypes in all participants. Clinical information was collected from the patients with cholesteatoma. RESULTS: The earwax pH was significantly less acidic in patients with cholesteatoma and those carrying wet earwax genotypes (ABCC11 538G/G or 538G/A) than in the controls and those carrying the dry earwax genotype (ABCC11 538A/A), respectively. Furthermore, earwax pH was significantly positively correlated with high preoperative cholesteatoma stages in the patients with cholesteatoma. CONCLUSION: Our results show that the less acidic earwax pH was significantly related to the development and progression of acquired middle ear cholesteatoma. The less acidic earwax pH may play an important role in the mechanism underlying the association between acquired middle ear cholesteatoma and the ABCC11 gene at site 538.

The use of earwax to determine livestock exposure to teratogenic lupine.

Lupines (Lupinus spp.) are a common plant species on western U.S. rangelands with several lupine species containing alkaloids that can be toxic and/or teratogenic to livestock. In North America, more than 150 lupine species are recognized with some ranches or grazing allotments containing multiple species. One or more of these lupine species may contain alkaloids that are teratogenic to cattle. Previous work has shown that lupine alkaloids can be detected in earwax of cattle grazing lupine infested rangelands. Our hypothesis is that earwax can be used to determine if cattle have been exposed to teratogenic alkaloids from multiple lupine species. Two lupine species, L. sericeus and L. polyphyllus, were present on a rangeland in east-central Idaho. The teratogen, anagyrine, was detected in L. sericeus and the teratogen, ammodendrine, was detected in L. polyphyllus plants collected on this rangeland. In this study, earwax was collected from 69 pregnant cows that had previously grazed a rangeland containing two different lupine species containing alkaloids that cause crooked calf syndrome (CCS). Anagyrine was detected in the earwax of all 69 cows sampled. Ammodendrine, was detected in the earwax of 28 of the 69 cows sampled. Earwax is a good non-invasive sample to aid in the diagnosis of cattle that have consumed lupine and does appear, in this case, to be a good diagnostic tool to differentiate between more than one lupine species that may be the cause of CCS. Concentrations of anagyrine or ammodendrine did not correlate with the incidence of CCS.

[Microbiome of the external auditory canal and preoperative preparation of patients in otosurgery (literature review)]. / Mikrobiom naruzhnogo slukhovogo prokhoda i predoperatsionnaya podgotovka patsientov v otokhirurgii (obzor literatury).

OBJECTIVE: To analyze the effectiveness of methods of antiseptic and hygienic preoperative preparation of the operating field in otosurgery. MATERIAL AND METHODS: A review and an expert assessment of the corresponding research objectives of scientific publications contained in the PubMed and Google Scholar databases have been carried out. RESULTS: Various studies indicate a lower ototoxicity of 5-10% of the drug povidone-iodine compared to others. Drugs, such as Miramistin, Okomistin, Dioxidine, are actively used in otiatrics in Russia, but no data on their ototoxicity have been noted. The collected data point to the relevance and prospects of studying the microbiome of the external auditory canal, assessing its effect on the course of the postoperative period, depending on various methods of preparation (antiseptic, removal of earwax and hair depilation) of the surgical field for otosurgery.

Association Between Earwax-Determinant Genotypes and Acquired Middle Ear Cholesteatoma in a Japanese Population.

OBJECTIVE: A single-nucleotide polymorphism 538G>A in the human ABCC11 gene is a determinant of the earwax morphotype. ABCC11 538GG and GA correspond to wet earwax and 538AA to dry earwax. Despite a putative positive correlation between the frequency of the 538G allele and the prevalence of cholesteatoma, minimal clinical information is currently available. We aimed to evaluate this association between the ABCC11 genotypes and acquired middle ear cholesteatoma. STUDY DESIGN: Case-control study. SETTING: Single-center academic hospital. METHODS: We recruited 67 Japanese patients with acquired middle ear cholesteatoma (cholesteatoma group) and 100 Japanese controls with no history of middle ear cholesteatoma. We assessed the ABCC11 genotypes for all participants. Clinical information was collected from the cholesteatoma group. The genotype data of 104 Japanese people from the 1000 Genomes Project who represent the general population were used. RESULTS: The proportion of participants with ABCC11 538GG or GA was significantly higher in the cholesteatoma group than in the control group or general Japanese population (P < .001). The ABCC11 538G allele frequency was also significantly higher in the cholesteatoma group than in the control group or general Japanese population (P < .001). Multivariate logistic regression analyses revealed a significant association between the ABCC11 genotype and acquired middle ear cholesteatoma (odds ratio, 5.49; 95% CI, 2.61-11.5; P < .001). CONCLUSION: Our results suggest that the ABCC11 genotypes could be associated with the development of acquired middle ear cholesteatoma among Japanese people.

Cerumenolytics with or without manual extraction for impacted earwax: A network meta-analysis of randomised clinical trials.

BACKGROUND: Many different substances for cerumenolysis have been evaluated in clinical trials. We carried out a systematic review and network meta-analysis to compare their effectiveness. METHODS: Electronic databases were searched for randomised clinical trials conducted in patients with impacted cerumen evaluating cerumenolytics. The primary outcome was the proportion of patients with wax clearance using manual techniques. Rankogram plot was used to assess the "best" cerumenolytic. Odds ratio (OR) with 95% confidence intervals (95% CI) was the effect estimate. RESULTS: Twenty-six studies were included in the systematic review and 25 in the meta-analysis. Sodium bicarbonate (OR: 2.68, 95% CI: 1.2, 6.1) and paradichlorobenzene (OR: 30.9, 95% CI: 5.9, 161.3) were associated with significantly greater proportions of patients with wax clearance following syringing compared to normal saline. Rankogram plot revealed paradichlorobenzene to have the highest probability of being the "best" cerumenolytic. Chlorobutanol was observed to be significantly better than normal saline in adults as well as following single application. Following multiple applications, glycerol, docusate sodium, hydrogen peroxide, oil, paradichlorobenzene, hydrogen peroxide/glycerol and arachis oil/chlorobutanol/paradichlorobenzene were observed with significant cerumenolytic activities. Urea/hydrogen peroxide/glycerol was observed with a significant cerumenolytic activity without the need for further interventions such as syringing/aspiration/suction. CONCLUSION: We observed several cerumenolytics to be effective in the treatment of impacted earwax when accompanied by additional manual techniques such as syringing/aspiration/suction.

Cerumen Management: An Updated Clinical Review and Evidence-Based Approach for Primary Care Physicians.

Objective: To provide family physicians with a practical, evidence-based approach to managing patients with cerumen impaction. Methods: MEDLINE, The Cochrane Library, and the Turning Research Into Practice (TRIP) database were searched for English-language cerumen impaction guidelines and reviews. All such articles published between 1992 and 2018 were reviewed, with most providing level II and III evidence. Results: Cerumen impaction is a common presentation seen in primary care and cerumen removal is one of the most common otolaryngologic procedures performed in general practice. Cerumen impaction is often harmless but can be accompanied by more serious symptoms. Cerumenolytics and irrigation of the ear canal are reasonable first-line therapies and can be used in conjunction or isolation. If irrigation and cerumenolytics are contraindicated, manual removal is appropriate, but the tools necessary are not commonplace in primary care clinics and specialized training may be required to prevent adverse outcomes. Conclusion: Family physicians play a key role in the assessment and management of cerumen impaction and are well equipped to do so. Knowledge of the available techniques for cerumen removal as well as their contraindications ensures that cerumen is removed safely and effectively. When cerumen removal cannot be removed safely in a primary care setting, referral to Otolaryngology-Head and Neck Surgery is appropriate.

Are human ATP-binding cassette transporter C11 and earwax associated with the incidence of cholesteatoma?

Cholesteatoma is an ear disease based on a locally destructive noncancerous conglomerate of epidermis and keratin debris. Abnormal growth of stratified keratinized squamous epithelium in the temporal bone causes destruction of the outer and middle ear, potentially leading to hearing impairment, facial palsy, vertigo, lateral sinus thrombosis, and intracranial complications. Although cholesteatoma is effectively treated by surgical resection (mastoidectomy), the lack of effective and nonsurgical therapies potentially results in fatal consequences, establishing the need for a comprehensive investigation of cholesteatoma pathogenesis. Although its etiology is still being debated, interestingly, we found that the trend associated with the 538G allele frequency of the adenosine triphosphate-binding cassette transporter C11 (ABCC11) gene, the determinant of wet-type earwax, and ethnic groups was similar to that between the incidence of cholesteatoma and ethnic groups (countries). The incidences of cholesteatoma in Europe (Denmark, Finland, and Scotland) are higher than in East Asia (Japan), and the frequencies of the ABCC11 538G allele in African, American, and European (Finland and Scotland) populations are higher than those in East Asian populations (Japan). Additionally, a single-nucleotide polymorphism in the ABCC11 gene (rs17822931, 538G > A; Gly180Arg) is closely related to earwax morphotypes. While earwax is often beneficial to ear health, it is sometimes harmful in cases where it causes hearing impairment. Based on independent findings of associations between ABCC11 and the physiological environment of the auditory canal, we hypothesize a possible link between ABCC11, earwax, and the incidence of cholesteatoma.

Clinical Practice Guideline (Update): Earwax (Cerumen Impaction)

Objective This update of the 2008 American Academy of Otolaryngology-Head and Neck Surgery Foundation cerumen impaction clinical practice guideline provides evidence-based recommendations on managing cerumen impaction. Cerumen impaction is defined as an accumulation of cerumen that causes symptoms, prevents assessment of the ear, or both. Changes from the prior guideline include a consumer added to the development group; new evidence (3 guidelines, 5 systematic reviews, and 6 randomized controlled trials); enhanced information on patient education and counseling; a new algorithm to clarify action statement relationships; expanded action statement profiles to explicitly state quality improvement opportunities, confidence in the evidence, intentional vagueness, and differences of opinion; an enhanced external review process to include public comment and journal peer review; and 3 new key action statements on managing cerumen impaction that focus on primary prevention, contraindicated intervention, and referral and coordination of care. Purpose The primary purpose of this guideline is to help clinicians identify patients with cerumen impaction who may benefit from intervention and to promote evidence-based management. Another purpose of the guideline is to highlight needs and management options in special populations or in patients who have modifying factors. The guideline is intended for all clinicians who are likely to diagnose and manage patients with cerumen impaction, and it applies to any setting in which cerumen impaction would be identified, monitored, or managed. The guideline does not apply to patients with cerumen impaction associated with the following conditions: dermatologic diseases of the ear canal; recurrent otitis externa; keratosis obturans; prior radiation therapy affecting the ear; previous tympanoplasty/myringoplasty, canal wall down mastoidectomy, or other surgery affecting the ear canal. Key Action Statements The panel made a strong recommendation that clinicians should treat, or refer to a clinician who can treat, cerumen impaction, defined as an accumulation of cerumen that is associated with symptoms, prevents needed assessment of the ear, or both. The panel made the following recommendations: (1) Clinicians should explain proper ear hygiene to prevent cerumen impaction when patients have an accumulation of cerumen. (2) Clinicians should diagnose cerumen impaction when an accumulation of cerumen, as seen on otoscopy, is associated with symptoms, prevents needed assessment of the ear, or both. (3) Clinicians should assess the patient with cerumen impaction by history and/or physical examination for factors that modify management, such as ≥1 of the following: anticoagulant therapy, immunocompromised state, diabetes mellitus, prior radiation therapy to the head and neck, ear canal stenosis, exostoses, and nonintact tympanic membrane. (4) Clinicians should not routinely treat cerumen in patients who are asymptomatic and whose ears can be adequately examined. (5) Clinicians should identify patients with obstructing cerumen in the ear canal who may not be able to express symptoms (young children and cognitively impaired children and adults), and they should promptly evaluate the need for intervention. (6) Clinicians should perform otoscopy to detect the presence of cerumen in patients with hearing aids during a health care encounter. (7) Clinicians should treat, or refer to a clinician who can treat, the patient with cerumen impaction with an appropriate intervention, which may include ≥1 of the following: cerumenolytic agents, irrigation, or manual removal requiring instrumentation. (8) Clinicians should recommend against ear candling for treating or preventing cerumen impaction. (9) Clinicians should assess patients at the conclusion of in-office treatment of cerumen impaction and document the resolution of impaction. If the impaction is not resolved, the clinician should use additional treatment. If full or partial symptoms persist despite resolution of impaction, the clinician should evaluate the patient for alternative diagnoses. (10) Finally, if initial management is unsuccessful, clinicians should refer patients with persistent cerumen impaction to clinicians who have specialized equipment and training to clean and evaluate ear canals and tympanic membranes. The panel offered the following as options: (1) Clinicians may use cerumenolytic agents (including water or saline solution) in the management of cerumen impaction. (2) Clinicians may use irrigation in the management of cerumen impaction. (3) Clinicians may use manual removal requiring instrumentation in the management of cerumen impaction. (4) Last, clinicians may educate/counsel patients with cerumen impaction or excessive cerumen regarding control measures.

Clinical Practice Guideline (Update): Earwax (Cerumen Impaction) Executive Summary

The American Academy of Otolaryngology-Head and Neck Surgery Foundation (AAO-HNSF) has published a supplement to this issue of Otolaryngology-Head and Neck Surgery featuring the updated Clinical Practice Guideline: Earwax (Cerumen Impaction). To assist in implementing the guideline recommendations, this article summarizes the rationale, purpose, and key action statements. The 11 recommendations emphasize proper ear hygiene, diagnosis of cerumen impaction, factors that modify management, evaluating the need for intervention, and proper treatment. An updated guideline is needed due to new evidence (3 guidelines, 5 systematic reviews, and 6 randomized controlled trials) and the need to add statements on managing cerumen impaction that focus on primary prevention, contraindicated intervention, and referral and coordination of care.

Plain Language Summary: Earwax (Cerumen Impaction)

This plain language summary serves as an overview in explaining earwax (cerumen). The summary applies to patients older than 6 months with a clinical diagnosis of earwax impaction and is based on the 2017 update of the Clinical Practice Guideline: Earwax (Cerumen Impaction). The evidence-based guideline includes research that supports diagnosis and treatment of earwax impaction. The guideline was developed to improve care by health care providers for managing earwax impaction by creating clear recommendations to use in medical practice.

Identification of volatile organic compounds in human cerumen.

We report here the initial examination of volatile organic compounds (VOCs) emanating from human earwax (cerumen). Recent studies link a single nucleotide polymorphism (SNP) in the adenosine triphosphate (ATP) binding cassette, sub-family C, member 11 gene (ABCC11) to the production of different types of axillary odorants and cerumen. ABCC11 encodes an ATP-driven efflux pump protein that plays an important function in ceruminous apocrine glands of the auditory canal and the secretion of axillary odor precursors. The type of cerumen and underarm odor produced by East Asians differ markedly from that produced by non-Asians. In this initial report we find that both groups emit many of the same VOCs but differ significantly in the amounts produced. The principal odorants are volatile organic C2-to-C6 acids. The physical appearance of cerumen from the two groups also matches previously reported ethnic differences, viz., cerumen from East Asians appears dry and white while that from non-Asians is typically wet and yellowish-brown.

Pharmacogenetics of human ABC transporter ABCC11: new insights into apocrine gland growth and metabolite secretion.

Cell secretion is an important physiological process that ensures smooth metabolic activities and tissue repair as well as growth and immunological functions in the body. Apocrine secretion occurs when the secretory process is accomplished with a partial loss of cell cytoplasm. The secretory materials are contained within secretory vesicles and are released during secretion as cytoplasmic fragments into the glandular lumen or interstitial space. The recent finding that the non-synonymous single nucleotide polymorphisms (SNP) 538G > A (rs17822931; Gly180Arg) in the ABCC11 gene determines the type of earwax in humans has shed light on the novel function of this ABC (ATP-binding cassette) transporter in apocrine glands. The wild-type (Gly180) of ABCC11 is associated with wet-type earwax, axillary osmidrosis, and colostrum secretion from the mammary gland as well as the potential risk of mastopathy. Furthermore, the SNP (538G > A) in the ABCC11 gene is suggested to be a clinical biomarker for the prediction of chemotherapeutic efficacy. The aim of this review article is to provide an overview on the discovery and characterization of genetic polymorphisms in the human ABCC11 gene and to explain the impact of ABCC11 538G > A on the apocrine phenotype as well as the anthropological aspect of this SNP in the ABCC11 gene and patients' response to nucleoside-based chemotherapy.