The epidermoid formation and its affinity to congenital cholesteatoma

Malformations Associated With Pediatric Congenital Cholesteatomas

OBJECTIVE

To describe malformations associated with pediatric congenital cholesteatomas of the middle ear.

STUDY DESIGN

Retrospective study.

SETTING

Tertiary referral center.

PATIENTS

One hundred and seventy-three cases of middle ear congenital cholesteatoma (CC) in 171 children operated between 2007 and 2017.

INTERVENTIONS

Demographic, clinical, and surgical data were collected from operative reports.

MAIN OUTCOME MEASURES

We first described the type and rate of malformations associated with CC. Secondly, we compared cholesteatoma features in two subgroups: anterior superior (AS) versus posterior superior (PS) starting point. Third, we compared demographic, clinical, and surgical data between patients with and without malformation.

RESULTS

CC was associated with malformations in 17 cases (17/173; 9.8%). The main malformation was preauricular fistula (8/173; 4.6%). Other malformations were: one first branchial cleft, two labio palatine cleft, one nasal cyst, two preauricular fibrochondroma, and five other malformations. PS congenital cholesteatomas were diagnosed in older children (4.6 versus 8.6 years, p < 0.05) and had greater extension in middle ear than the AS cholesteatoma (39.7% versus 95.8%, p < 0.05). We did not find any significant difference between these two groups regarding the associated malformations. We did not find a difference in clinical presentation of CC between patients with and without associated malformation.

CONCLUSIONS

We found various associated malformations in 9.8% of CC cases with no statistical difference in the malformation rate between AS and PS groups. All the malformations were located in the craniofacial region suggesting that genes implicated in craniofacial development may play a role in the pathophysiology of CC.

A new theory on the pathogenesis of acquired cholesteatoma: Mucosal traction

OBJECTIVES/HYPOTHESIS

Although the migration of its squamous outer surface of the tympanic membrane has been well characterized, there is a paucity of data available concerning the migratory behavior of its medial mucosal surface. Existing theories of primary acquired cholesteatoma pathogenesis do not adequately explain the observed characteristics of the disease. We propose a new hypothesis, based upon a conjecture that mucosal membrane interactions are the driving force in cholesteatoma.

STUDY DESIGN

A retrospective chart review and a prospective observational cohort study in rats.

METHODS

After developing the new theory, it was tested through both clinical and experimental observations. To evaluate whether impairment of middle ear mucociliary migration would influence cholesteatoma formation, a retrospective chart review evaluating cholesteatoma occurrence in a sizable population of patients with either primary ciliary dyskinesia (PCD) or cystic fibrosis (CF) was performed. To study mucosal migration on the medial aspect of the tympanic membrane, ink tattoos were monitored over time in a rat model.

RESULTS

No cholesteatomas were identified in either PCD patients (470) or in CF patients (1,910). In the rat model, mucosa of the posterior pars tensa migrated toward the posterior superior quadrant, whereas the mucosa of the anterior pars tensa migrated radially toward the annulus.

CONCLUSION

Mucosal coupling with traction generated by interaction of migrating opposing surfaces provides the first comprehensive theory that explains the observed characteristics of primary acquired cholesteatoma. The somewhat counterintuitive hypothesis that cholesteatoma is fundamentally a mucosal disease has numerous therapeutic implications.

Where does treatment optimism fit in? Examining factors associated with consistent condom use among people receiving antiretroviral treatment in Rio de Janeiro, Brazil

In the era of highly active antiretrovirals, people living with HIV (PLWH) have resumed sexual activity in the context of longer and healthier lives, and thus the chances of transmitting the HIV virus, as well as the potential to be re-infected also increase. HIV treatment optimism has been found to be associated with sexual risk behaviors among PLWH in different settings. A cross sectional survey was conducted to examine the relationship between treatment optimism, safer sex burnout and consistent condom use as well as variables associated with treatment optimism in a sample of PLWH on antiretrovirals (ARVs) in Rio de Janeiro, Brazil (n = 604). Seventy-two percent of participants always used a condom in the last 6 months. Homosexual, bisexual, transexual persons were less likely to use condoms consistently than heterosexuals (AOR .58 CI .42-.78). Those who were treatment optimistic (AOR .46 CI .25-.88) were more likely not use a condom consistently in the past 6 months, as were participants who reported safer sex burnout (AOR .58 CI .36-.90). Sexual orientation, safer sex burnout, and lower education levels were significantly associated with higher treatment optimism in multivariate analysis. Study findings highlight the need to address psychosocial factors such as treatment optimism and safer sex burnout associated with lower consistent condom use among PLWH in Rio de Janeiro, Brazil.

Contemporary assessment and management of congenital cholesteatoma

PURPOSE OF REVIEW

Only 2-4% of cholesteatomas presenting to pediatric otologists are congenital in origin. Disease severity can range from intratympanic pearls to middle ear and mastoid obliteration. Recently, highlighted variations of this rare disorder warrant a systematic approach to disease assessment and surgical decision making. This review provides a comprehensive method to diagnose and manage congenital cholesteatoma based on current literature.

RECENT FINDINGS

The holding theory of the origin of congenital cholesteatomas is that they arise from retained epithelial cell rest. Primary development can vary among sites within the middle ear and mastoid. 'Open' and 'closed' varieties have been proposed. However, disease severity depends on location, patient age, ossicular integrity, and number of anatomic sites involved. These variables have inspired the development of staging systems whereby appropriate surgical approaches can be designed. Computed tomography (CT) scans are necessary and continue to be the best radiographic tool for surgical planning. Over 30% of congenital cholesteatomas can be extirpated through a transcanal approach. Involvement of the posterior quadrant, over three anatomic subsites, or the mastoid cavity obligates standard canal wall-up techniques. Canal wall-down procedures are rarely required.

SUMMARY

Congenital cholesteatomas frequently extend beyond the typically described anterosuperior location of the middle ear. Ossicular destruction, mastoid infiltration, and tympanic membrane rupture are encountered more frequently than previously thought. Advanced disease predominately occurs in older children and requires sophisticated assessment and surgical planning beyond removing a simple keratin cyst.

Growth of cholesteatoma by implantation of epithelial tissue along the femoral bone of rats

Cholesteatoma is a well-known infection resembling a pearl. Its histological aspect is of an epidermal cyst formation characterized by epidermal-keratinized tissue in the middle ear and mastoid that can migrate and erode to adjacent structures.

AIM

To verify epidermal cyst (cholesteatoma) growth through implantation of auricular skin of a mouse next to its femoral bone.

STUDY DESIGN

Experimental.

MATERIAL AND METHOD

Ten healthy rats between two and five months of age and of both sexes underwent implantation of auricular skin on the femoral bone during a three-month period. Paraffin-embedded sections were obtained from the sample and stained with hematoxylin and eosin for pathology investigation.

RESULTS

Macroscopic view: round soft yellowish granulation tissue. Microscopic view: keratinizing stratified squamous epithelium cystic formation. The cyst presented innermost corneal layer, resulted from keratinized skin, followed by granulated and squamous layers, and outermost basal layer.

CONCLUSIONS

Growth of epidermal cyst (cholesteatoma) may start from a transplanted epithelial tissue next to the femoral bone of rats.

Recognize cholesteatomas early

Cholesteatomas are benign tumors that develop in the middle ear, and their rapid growth patterns can impinge on local structures, resulting in adverse sequelae such as hearing loss, pain, or neuropathies. These late signs and symptoms can be avoided by early identification and prompt intervention. Primary care providers should be aware of the incidence, prevalence, identification, and associated symptoms of cholesteatomas to reduce the later untoward affects and promote prompt referral.

Etiopathogenesis of cholesteatoma

Cholesteatoma is a destructive lesion of the temporal bone that gradually expands and causes complications by erosion of the adjacent bony structures. Bone resorption can result in destruction of the ossicular chain and otic capsule with consecutive hearing loss, vestibular dysfunction, facial paralysis and intracranial complications. Surgery is the only treatment of choice. The etiopathogenesis of cholesteatoma, however, is still controversial. This review was designed to understand the reasons for these disparities and to reduce or eliminate them. Future studies focused on developmental, epidemiological, hormonal and genetic factors as well as on treatment are likely to contribute to further understanding of cholesteatoma pathogenesis.

Immunohistochemical characterization of the epidermoid formation in the middle ear

OBJECTIVE

To study the incidence, size, and origin of epidermoid formations after accurately characterizing them by cytokeratin immunohistochemical analysis.

STUDY DESIGN

A strategy of screening sections for possible epidermoid formations in the entire eardrum area in paraffin-embedded, serially sectioned developing temporal bones was used. Unstained adjacent sections were subjected to immunohistochemical staining, to provide accurately identified epidermoid formations for a study of their appearance and size in relation to age.

METHODS

The immunohistochemical expression patterns for epidermoid cytokeratins of several antibodies at different gestational ages were determined. Then, epithelial structures suspected as epidermoid formations were characterized as epidermoid with age-appropriate antibodies in 36 paraffin-embedded temporal bones from 19 cases with an age range of 6 gestational weeks to 15 months postpartum using a novel method of antigen retrieval by heating sections in a 70 degrees C water bath.

RESULTS

Each of 22 temporal bones ranging in age from 16 weeks gestation to 8 months postpartum contained one or more, often numerous, epidermoid formations. Sizes of epidermoid formations increased significantly with increasing age. The formations were found anywhere in the annular lateral wall region of middle ear, but the majority were in the anterosuperior region. A further study of the interface between annular external canal epidermis and middle ear epithelium in a larger group suggested that epidermoid formations arise at approximately 16 gestational weeks from the external canal epidermis.

CONCLUSION

The findings indicate that epidermoid tissue in the middle ear normally originates from external canal epidermis at approximately the 16th gestational week and grows before disappearing.

Cholesteatoma behind an intact tympanic membrane: histopathologic evidence for a tympanic membrane origin

BACKGROUND

Several theories have been proposed with respect to the origin and pathogenesis of cholesteatoma behind an intact tympanic membrane.

CASE REPORT

The authors describe a case of cholesteatoma behind an intact tympanic membrane in a 71-year-old man with a history of tympanic membrane retraction fixed to the incus without evidence of a perforation. The membrane eventually became detached, and remnants of keratinizing squamous epithelium were found on the incus.

DISCUSSION

Mechanisms such as metaplasia, ectopic epidermis rests, or ingrowth of meatal epidermis have been proposed to explain the pathogenesis of cholesteatoma behind an intact tympanic membrane. These findings, based on temporal bone histopathology, support the role of an acquired epidermal rest.

CONCLUSIONS

This case report provides evidence that cholesteatoma behind an intact tympanic membrane can be established from a resolved retraction of the pars tensa of the tympanic membrane.