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Only a few years have passed since the discovery of polar nematics, and now they are becoming the most actively studied liquid-crystal materials. Despite numerous breakthrough findings made recently, a theoretical systematization is still lacking. In the present paper, we take a step toward systematization. The powerful technique of molecular-statistical physics has been applied to an assembly of polar molecules influenced by electric field. Three polar nematic phases were found to be stable at various conditions: the double-splay ferroelectric nematic N_{F}^{2D} (observed in the lower-temperature range in the absence of or at low electric field), the double-splay antiferroelectric nematic N_{AF} (observed at intermediate temperature in the absence of or at low electric field), and the single-splay ferroelectric nematic N_{F}^{1D} (observed at moderate electric field at any temperature below transition into paraelectric nematic N and in the higher-temperature range (also below N) at low electric field or without it. A paradoxical transition from N_{F}^{1D} to N induced by application of higher electric field has been found and explained. A transformation of the structure of polar nematic phases at the application of electric field has also been investigated by Monte Carlo simulations and experimentally by observation of polarizing optical microscope images. In particular, it has been realized that, at planar anchoring, N_{AF} in the presence of a moderate out-of-plane electric field exhibits twofold splay modulation: antiferroelectric in the plane of the substrate and ferroelectric in the plane normal to the substrate. Several additional subtransitions related to fitting the confined geometry of the cell by the structure of polar phases were detected.
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We have elaborated a theoretical approach for the description of polar nematic phases observed by Nishikawa et al. [Adv. Mater. 29, 1702354 (2017)0935-964810.1002/adma.201702354], their structures, and transitions between them. Specific symmetry contributions to the pair molecular potentials provide the molecular mechanisms responsible for the formation of proper and improper polarity on the macroscopic level. An improper antiferroelectric nematic M2 phase can arise between paraelectric nematic M1 and proper ferroelectric nematic MP in the temperature scale. The local polarization in M2 arises mostly due to the local splay deformation. The director distribution in M2 represents the conjugation of cylindrical waves with opposite splay and polarization signs. The director and polarization are parallel to the cylindrical domain axes in the middle of each cylinder but exhibit considerable (mostly radial) deformation on the periphery of each cylinder. Polarization vectors are mostly stacked antiparallel on the borders between the domains without the director disruption. The domain size decreases with the decreasing temperature, the percentage of the antiferroelectric decouplings increases, and M2 exhibits the first-order phase transition into proper ferroelectric MP. With the increasing temperature the domain size in the M2 phase increases, the domination of particular polar orientation of molecules reduces, and finally, the domain size diverges at particular temperature corresponding to the second-order phase transition from M2 to paraelectric M1. Variations of the polar and nonpolar orientational order parameters are estimated within each phase and between the phases. Our experimental and computer simulation results (also presented in the paper) fully support our theoretical findings.
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OBJECTIVE: This study aimed to propose appropriate management for odontogenic chronic rhinosinusitis. METHOD: Thirty-one adult patients with odontogenic chronic rhinosinusitis undergoing maxillary extraction were retrospectively analysed. Patients with (n = 21) and without (n = 10) oroantral fistula on computed tomography were classified. Functional endoscopic sinus surgery was performed when sinusitis did not improve after extraction. The critical indicators for surgical requirement in the management of odontogenic chronic rhinosinusitis were analysed. RESULTS: Sinusitis significantly improved after extraction in both groups. Patients without oroantral fistula had significantly more severe remnant sinusitis than those with oroantral fistula after extraction on computed tomography (p = 0.0037). The requirement for functional endoscopic sinus surgery was statistically significant for patients without orofacial fistula over those with orofacial fistula (p < 0.0001). The surgical improvement ratio was 93 per cent. CONCLUSION: The absence of oroantral fistula and severe sinusitis can be critical indicators for the requirement of functional endoscopic sinus surgery after extraction in the management of odontogenic chronic rhinosinusitis.
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Sinusite Maxilar/terapia , Cirurgiões Bucomaxilofaciais/psicologia , Otorrinolaringologistas/psicologia , Rinite/terapia , Doenças Dentárias/complicações , Adulto , Idoso , Atitude do Pessoal de Saúde , Doença Crônica , Tomada de Decisão Clínica , Gerenciamento Clínico , Feminino , Humanos , Masculino , Sinusite Maxilar/diagnóstico , Sinusite Maxilar/etiologia , Pessoa de Meia-Idade , Estudos Retrospectivos , Rinite/diagnóstico , Rinite/etiologia , Doenças Dentárias/cirurgia , Extração Dentária/estatística & dados numéricosRESUMO
OBJECTIVE: This study aimed to determine the predictors of disease progression after functional endoscopic sinus surgery in patients with chronic rhinosinusitis. METHOD: A total of 281 adult chronic rhinosinusitis patients who underwent primary bilateral functional endoscopic sinus surgery between 2007 and 2017 and had at least 12 months of follow-up endoscopic evaluation were examined. Patients were divided into eosinophilic (n = 205) and non-eosinophilic chronic rhinosinusitis groups (n = 76). In order to determine adverse factors, post-operative endoscopic appearance scores were analysed in relation to the pre- and intra-operative findings using multiple regression analyses. RESULTS: The post-operative course of eosinophilic cases deteriorated over time, like the early period for non-eosinophilic cases. Frontal sinus polyps recurred early in eosinophilic chronic rhinosinusitis. Multivariate analyses indicated young adulthood, asthma, high computed tomography score and frontal sinus polyps as significant adverse predictors. CONCLUSION: Early, appropriate estimation of sinonasal conditions appears to be crucial for successful surgical management of chronic rhinosinusitis.
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Eosinófilos/metabolismo , Seio Frontal/patologia , Rinite/cirurgia , Sinusite/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Progressão da Doença , Endoscopia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Rinite/sangue , Rinite/diagnóstico , Fatores de Risco , Sinusite/sangue , Sinusite/diagnóstico , Adulto JovemRESUMO
Sea surface temperature (SST) fronts in mid- to high-latitude oceans have significant impacts on extratropical atmospheric circulations and climate. In the western subarctic Pacific, sharp SST fronts form between the cold subarctic water and the recently found quasi-stationary jets that advect warm waters originating in the Kuroshio northeastward. Here we present a new mechanism of the jet formation paying attention to the propagation of baroclinic Rossby waves that is deflected by eddy-driven barotropic flows over bottom rises, although their height is low (~500 m) compared with the depth of the North Pacific Ocean (~6000 m). Steered by the barotropic flows, Rossby waves bring a thicker upper layer from the subtropical gyre and a thinner upper layer from the subarctic gyre, thereby creating a thickness jump, hence a surface jet, where they converge. This study reveals an overlooked role of low-rise bottom topography in regulating SST anomalies in subpolar oceans.
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Low-flow venous malformations are congenital lesions and they are the third most common vascular anomaly in the head and neck. In this paper, the third in a series of three educational reviews, we discuss current trends in their management, and include a summary of common sclerosant agents used in their control.
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Cabeça/irrigação sanguínea , Pescoço/irrigação sanguínea , Malformações Vasculares/terapia , Veias/anormalidades , Humanos , Escleroterapia/métodos , Malformações Vasculares/diagnóstico , Malformações Vasculares/diagnóstico por imagem , Malformações Vasculares/cirurgia , Veias/diagnóstico por imagem , Veias/cirurgiaRESUMO
We compared Wisteria floribunda agglutinin-positive Mac-2-binding protein (WFA+ -M2BP) levels between patients with chronic hepatitis B (n=249) and chronic hepatitis C (n=386) based on the degree of liver fibrosis. We examined WFA+ -M2BP levels in patients with F4 (cirrhosis), F3 or more (advanced fibrosis) and F2 or more (significant fibrosis) in the two groups. We further examined the relationship between five fibrosis markers and the degree of fibrosis. The WFA+ -M2BP values ranged from 0.25 cut-off index (COI) to 12.9 COI in patients with hepatitis B and 0.34-20.0 COI in patients with hepatitis C (P<.0001). The median WFA+ -M2BP values in F4 in the two groups were 2.83 COI in patients with hepatitis B and 5.03 COI in patients with hepatitis C (P=.0046). The median WFA+ -M2BP values in F3 or more in the two groups were 1.79 COI in patients with hepatitis B and 3.79 COI in patients with hepatitis C (P<.0001). The median WFA+ -M2BP values in F2 or more in the two groups were 1.49 COI in the hepatitis B cohort and 3.19 COI in the hepatitis C group (P<.0001). Among five liver fibrosis markers, WFA+ -M2BP had the highest correlation coefficient (rs =.629) in terms of correlation with the degree of fibrosis in the patients with hepatitis C and had the second highest rs value (.415) in the hepatitis B group. Although WFA+ -M2BP could be a useful indicator of liver fibrosis, WFA+ -M2BP levels in the two groups significantly differed even in the same degree of fibrosis. Individual cut-off values in each aetiology for the degree of fibrosis should be determined.
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Antígenos de Neoplasias/sangue , Antígenos de Neoplasias/metabolismo , Hepatite B Crônica/patologia , Hepatite C Crônica/patologia , Glicoproteínas de Membrana/sangue , Glicoproteínas de Membrana/metabolismo , Lectinas de Plantas/metabolismo , Receptores de N-Acetilglucosamina/metabolismo , Soro/química , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ligação Proteica , Adulto JovemRESUMO
The surgical treatment of defects caused by noma is challenging for the surgeon and the patient. Local flaps are preferred, but sometimes, because of the nature of the disease, there is not enough local tissue available. We describe our experience of free tissue transfer in Ethiopia. Between 2008 and 2014, 34 microsurgical procedures were done over 11 missions with the charity Facing Africa, predominantly for the treatment of defects caused by noma (n=32). The mean duration of operation was 442 minutes (range 200 - 720). Six minor wound infections were treated conservatively and did not affect outcome, a return to theatre was required in 4 patients with wound infections and one with a haemorrhage; 2 flaps failed and 2 partially failed, one patient developed an oronasal fistula, and one had an infection at the donor site that required a repeat graft. In settings where resources are limited, free flaps can be used when local tissue is not available and they cause less morbidity than pedicled tissue transfer.
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Face/cirurgia , Microvasos/cirurgia , Procedimentos de Cirurgia Plástica , Retalhos de Tecido Biológico/cirurgia , Humanos , Microcirurgia , Noma/cirurgia , Retalhos Cirúrgicos/cirurgiaRESUMO
We describe a series of 8 patients who had total reconstruction of the nose during 4 separate missions to Ethiopia. The aetiology was noma (n=3), assault (n=2), acid burn (n=1), squamous cell carcinoma (n=1), and a sequela of meningococcal septicaemia (n=1). Reconstruction was with forehead flaps when adequate tissue was available (n=6) and with radial forearm flaps when it was not (n=2). Some reconstructive approaches require procedures to be done in stages, and in settings where resources are limited, difficulties with the continuity of care and provision for the management of complications, must be overcome.
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Nariz/cirurgia , Procedimentos de Cirurgia Plástica , Humanos , Noma/cirurgia , Neoplasias Nasais/cirurgia , Retalhos Cirúrgicos/cirurgiaRESUMO
We report the formation of a nonmagnetic band insulator at the isopolar interface between the antiferromagnetic Mott-Hubbard insulator LaTiO_{3} and the antiferromagnetic charge transfer insulator LaFeO_{3}. By density-functional theory calculations, we find that the formation of this interface state is driven by the combination of O band alignment and crystal field splitting energy of the t_{2g} and e_{g} bands. As a result of these two driving forces, the Fe 3d bands rearrange and electrons are transferred from Ti to Fe. This picture is supported by x-ray photoelectron spectroscopy, which confirms the rearrangement of the Fe 3d bands and reveals an unprecedented charge transfer up to 1.2±0.2 e^{-}/interface unit cell in our LaTiO_{3}/LaFeO_{3} heterostructures.
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Lantânio/química , Modelos Químicos , Óxidos/química , Titânio/química , Elétrons , Espectroscopia Fotoeletrônica/métodosRESUMO
BACKGROUND: NY-ESO-1 antibodies are specifically observed in patients with NY-ESO-1-expressing tumours. We analysed whether the NY-ESO-1 humoral immune response is a useful tumour marker of gastric cancer. METHODS: Sera from 363 gastric cancer patients were screened by enzyme-linked immunosorbent assay (ELISA) to detect NY-ESO-1 antibodies. Serial serum samples were obtained from 25 NY-ESO-1 antibody-positive patients, including 16 patients with curative resection and 9 patients who received chemotherapy alone. RESULTS: NY-ESO-1 antibodies were detected in 3.4% of stage I, 4.4% of stage II, 25.3% of stage III, and 20.0% of stage IV patients. The frequency of antibody positivity increased with disease progression. When the NY-ESO-1 antibody was used in combination with carcinoembryonic antigen and CA19-9 to detect gastric cancer, information gains of 11.2% in stages III and IV, and 5.8% in all patients were observed. The NY-ESO-1 immune response levels of the patients without recurrence fell below the cutoff level after surgery. Two of the patients with recurrence displayed incomplete decreases. The nine patients who received chemotherapy alone continued to display NY-ESO-1 immune responses. CONCLUSION: When combined with conventional tumour markers, the NY-ESO-1 humoral immune response could be a useful tumour marker for detecting advanced gastric cancer and inferring the post-treatment tumour load in seropositive patients.
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Anticorpos Antineoplásicos/sangue , Antígenos de Neoplasias/imunologia , Biomarcadores Tumorais/sangue , Proteínas de Membrana/imunologia , Neoplasias Gástricas/imunologia , Idoso , Antígenos Glicosídicos Associados a Tumores/análise , Antígeno Carcinoembrionário/análise , Progressão da Doença , Feminino , Humanos , Imunidade Humoral , Masculino , Pessoa de Meia-Idade , Prognóstico , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/patologia , Carga TumoralRESUMO
PURPOSE OF INVESTIGATION: To assess the clinical relevance of serum growth-regulated oncogene alpha (GROalpha) levels in gynecological cancer, we investigated its concentration in distinguishing patients with cervical cancer, endometrial cancer, ovarian cancer, benign ovarian tumor and control. METHODS: Preoperative serum GROalpha levels were measured in women with cervical cancer (n=46), endometrial cancer (n=39), ovarian cancer (n=124), benign ovarian tumors (n=52), and normal controls (n=38) using an enzyme-linked immunosorbent assay. RESULTS: Statistical analyses showed that the serum GROalpha concentration was significantly elevated in the cervical cancer, endometrial cancer and ovarian cancer patients compared with controls. Using GROalpha levels, the receiver operating characteristic (ROC) of cervical cancer (AUC approximately 0.775), endometrial cancer (AUC approximately 0.799), ovarian cancer (AUC approximately 0.749) and benign ovarian tumors (AUC approximately 0.568) vs. controls were identified. CONCLUSION: Our findings suggest that serum GROalpha measurement as a molecular marker might contribute to detection and diagnosis of gynecological cancer.
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Biomarcadores Tumorais/sangue , Carcinoma/sangue , Quimiocina CXCL1/sangue , Neoplasias Ovarianas/sangue , Neoplasias do Colo do Útero/sangue , Adenocarcinoma de Células Claras/sangue , Adenocarcinoma Mucinoso/sangue , Área Sob a Curva , Carcinoma Endometrioide/sangue , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Modelos Logísticos , Pessoa de Meia-Idade , Cistos Ovarianos/sangue , Curva ROC , Estatísticas não ParamétricasRESUMO
To clarify the relationship between Helicobacter pylori (H. pylori), a risk factor for gastritis, peptic ulcer and gastric cancer, and proteinase-activated receptors (PARs) that contribute to inflammatory responses, we determined and characterized the biological activity of H. pylori components in the mammalian cells that express PARs. The activity of H. pylori extracts was assessed in distinct cell lines with high expression of PAR1 (RGM1 cells), PAR2 (A549 cells), or PAR2 and PAR4 (HCT-15 cells). A PAR1-activating peptide (AP), but not H. pylori extracts, caused prostaglandin E2 (PGE2) release in RGM1 cells. On the other hand, H. pylori extracts produced release of PGE2 and interleukin-8 (IL-8) in A549 and HCT-15 cells, respectively, as a PAR2-AP did. The activity of H. pylori extracts in A549 cells was not affected by a proteinase inhibitor or exposure to boiling, but abolished by inhibitors of lipopolysaccharide (LPS), IRAK-1/4 or NF-κB. The activity of H. pylori extracts in HCT-15 cells was partially suppressed by boiling or the proteinase inhibitor. In rat platelets that express PAR4 and PAR3, like a PAR4-AP, H. pylori extracts induced aggregation when assessed in platelet rich plasma, an effect unaffected by the proteinase inhibitor, but did not cause aggregation of washed rat platelets that responded to the PAR4-AP or thrombin. The present study thus shows the biological activities of H. pylori extracts in A549 and HCT-15 cells or rat platelets, and suggests that they are not mediated by any PAR-activating proteinases, but may involve the other pathogenic factors including LPS.
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Helicobacter pylori/metabolismo , Receptores Ativados por Proteinase/metabolismo , Animais , Proteínas de Bactérias/metabolismo , Plaquetas/metabolismo , Linhagem Celular Tumoral , Dinoprostona/metabolismo , Temperatura Alta , Humanos , Interleucina-8/metabolismo , Lipopolissacarídeos/metabolismo , Masculino , Oligopeptídeos/farmacologia , Agregação Plaquetária , Inibidores de Proteases/farmacologia , Desnaturação Proteica , Inibidores de Proteínas Quinases/farmacologia , Ratos , Ratos Wistar , Receptor PAR-1/metabolismo , Receptor PAR-2/metabolismo , Receptores Ativados por Proteinase/efeitos dos fármacos , Receptores de Trombina/metabolismo , Trombina/metabolismoRESUMO
Despite its potential for use in large-scale analyses, previous attempts to utilise administrative data to identify healthcare-associated infections (HAI) have been shown to be unsuccessful. In this study, we validate the accuracy of a novel method of HAI identification based on antibiotic utilisation patterns derived from administrative data. We contemporaneously and independently identified HAIs using both chart review analysis and our method from four Japanese hospitals (N=584). The accuracy of our method was quantified using sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) relative to chart review analysis. We also analysed the inter-rater agreement between both identification methods using Cohen's kappa coefficient. Our method showed a sensitivity of 0.93 (95% CI: 0.87-0.96), specificity of 0.91 (0.89-0.94), PPV of 0.75 (0.68-0.81) and NPV of 0.98 (0.96-0.99). A kappa coefficient of 0.78 indicated a relatively high level of agreement between the two methods. Our results show that our method has sufficient validity for identification of HAIs in large groups of patients, though the relatively lower PPV may imply limited utilisation in the pinpointing of individual infections. Our method may have applications in large-scale HAI identification, risk-adjusted multicentre studies involving cost of illness, or even as the starting point of future cost-effectiveness analyses of HAI control measures.
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Antibacterianos/uso terapêutico , Infecção Hospitalar/diagnóstico , Uso de Medicamentos/estatística & dados numéricos , Métodos Epidemiológicos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Hospitais , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Sensibilidade e EspecificidadeRESUMO
Craniofacial conditions are mainly treated within England by four supra-regional centres. Due to a continuous increase in the number of cases referred to our service we audited the source and nature of these referrals. Data was prospectively collected over a four-year period from April 2004 to March 2008. The speciality of the referring clinicians was recorded, along with the diagnosis. A year-by-year increase in the number of referrals from 138 in 2004-2005 to 253 in 2007-2008 was seen. There was a 214% increase in the number of patients referred with single suture craniosynostosis, a 520% increase in patients with benign hyperplastic conditions such as fibrous dysplasia, neurofibromatosis and vascular anomalies and a 220% increase in patients treated elsewhere but now needing revision surgery. A 407% increase in referrals for positional plagiocephaly was recorded. Our referral pattern reflects the internationally accepted increase in the incidence of metopic synostosis and positional plagiocephaly. Due to the skill mix and experience present in a designated craniofacial service other benign hyperplastic and hypoplastic conditions are increasingly being referred. Additional referrals have come from a change in the referral pathway. To manage the increased workload we have established separate clinics to manage vascular anomalies and have adopted a policy of not reviewing patients with positional plagiocephaly.
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Anormalidades Craniofaciais/epidemiologia , Procedimentos Cirúrgicos Ortognáticos/estatística & dados numéricos , Pediatria/estatística & dados numéricos , Procedimentos de Cirurgia Plástica/estatística & dados numéricos , Atenção Primária à Saúde/estatística & dados numéricos , Encaminhamento e Consulta/estatística & dados numéricos , Fatores Etários , Criança , Pré-Escolar , Estudos de Coortes , Anormalidades Craniofaciais/diagnóstico , Anormalidades Craniofaciais/cirurgia , Humanos , Lactente , Auditoria Médica , Estudos RetrospectivosRESUMO
Metastasis of malignant tumors to the oral cavity is rare. The authors report a case of thyroid carcinoma with mandibular osteoblastic metastasis. An 83-year-old female presented with lower jaw swelling and pain. An elastic hard subcutaneous mass was observed in the median mandible. X-ray images confirmed a tumor lesion with periosteal reaction spreading radially from the mandible. A biopsy revealed nests of large, polygonal tumor cells growing in a supporting fibrovascular framework. The patient's anamnesis included thyroid carcinoma with lung metastasis, 2 years ago, treated by total enucleation of the thyroid and excision of the superior lobe of the left lung. Biopsy, primary and metastatic tumor samples all tested positive for thyroglobulin, suggesting a thyroid follicular epithelial origin. Mandibular metastasis of poorly differentiated carcinoma of the thyroid gland was diagnosed. Consent for further treatment was not obtained. The patient died 1 year and 7 months later.
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Carcinoma/secundário , Neoplasias Mandibulares/secundário , Neoplasias da Glândula Tireoide/patologia , Idoso , Biópsia , Antígeno CD56/análise , Carcinoma/patologia , Evolução Fatal , Feminino , Humanos , Queratina-7/análise , Neoplasias Pulmonares/secundário , Neoplasias Mandibulares/patologia , Osteoblastos/patologia , Periósteo/patologia , Tireoglobulina/análise , Tomografia Computadorizada por Raios XRESUMO
OBJECTIVES: We report an extremely rare case of congenital cholesteatoma of the mastoid region, presenting as acute mastoiditis. We also review the 16 previously reported cases of congenital cholesteatoma of the mastoid region. CASE REPORT: A 65-year-old man presented with left-sided, post-auricular swelling and pain. Acute mastoiditis was diagnosed, with computed tomography demonstrating destruction of the bony plates of the posterior cranial fossa and sigmoid sinus. Initial surgery revealed a cholesteatoma in the mastoid, with no extension into the aditus ad antrum or attic. These findings were confirmed by pathological and immunohistochemical analysis of the surgical specimen, the latter using involucrin. The cholesteatoma matrix was completely removed in a second operation. CONCLUSIONS: Including this case, only four of the 17 reported cases of congenital cholesteatoma of the mastoid region showed post-auricular pain or swelling, indicating acute mastoiditis. Clinicians should bear in mind that congenital cholesteatoma may be present in patients presenting with mastoiditis, particularly adults.