Biofilm-coated microbeads and the mouse ear skin: An innovative model for analysing anti-biofilm immune response in vivo.

Owing to its ability to form biofilms, Staphylococcus aureus is responsible for an increasing number of infections on implantable medical devices. The aim of this study was to develop a mouse model using microbeads coated with S. aureus biofilm to simulate such infections and to analyse the dynamics of anti-biofilm inflammatory responses by intravital imaging. Scanning electron microscopy and flow cytometry were used in vitro to study the ability of an mCherry fluorescent strain of S. aureus to coat silica microbeads. Biofilm-coated microbeads were then inoculated intradermally into the ear tissue of LysM-EGFP transgenic mice (EGFP fluorescent immune cells). General and specific real-time inflammatory responses were studied in ear tissue by confocal microscopy at early (4-6h) and late time points (after 24h) after injection. The displacement properties of immune cells were analysed. The responses were compared with those obtained in control mice injected with only microbeads. In vitro, our protocol was capable of generating reproducible inocula of biofilm-coated microbeads verified by labelling matrix components, observing biofilm ultrastructure and confirmed in vivo and in situ with a matrix specific fluorescent probe. In vivo, a major inflammatory response was observed in the mouse ear pinna at both time points. Real-time observations of cell recruitment at injection sites showed that immune cells had difficulty in accessing biofilm bacteria and highlighted areas of direct interaction. The average speed of cells was lower in infected mice compared to control mice and in tissue areas where direct contact between immune cells and bacteria was observed, the average cell velocity and linearity were decreased in comparison to cells in areas where no bacteria were visible. This model provides an innovative way to analyse specific immune responses against biofilm infections on medical devices. It paves the way for live evaluation of the effectiveness of immunomodulatory therapies combined with antibiotics.

Preparing the surgical area for non-shaved ear surgery: a clinical assessment.

OBJECTIVE: To review the clinical experience for non-shaved middle ear/mastoid surgery and evaluate the proper method of preparing the postauricular surgical field. METHODS: This retrospective study reviewed medical records of cases where the non-shaved surgical procedure was carried out for middle ear/mastoid diseases. In all cases, middle ear and mastoid surgery was performed by one otologic surgeon without hair shaving to treat chronic perforation of tympanic membrane, as well as chronic suppurative otitis media, with or without mastoiditis during two years. The prevalence of surgical site infection (SSI) and bacterial culture of the surgical field was assessed just before the skin incision. RESULTS: In this review of 106 cases, the SSI rate was 1.6% for the non-shaved ear surgery. Bacterial colonisation was found on the prepared surgical field in 8.5% of cases and these bacteria was different from true pathogens. SSI of the skin incision occurred in two cases, although no bacterial colonisation of the non-shaved surgical field was found. The surgical exposure of postauricular area was enough to do tympanoplasty or tympanomastoidectomy, even though in cases where a hairline was close to postauricular sulcus. CONCLUSION: This study showed that when preparing the non-shaved ear surgery, the surgeons should not have to worry about skin contamination by hair. We suggest that the non-shaved ear surgery would appear to be preferable for the postauricular approach.

Tuberculosis cutánea en pabellón auricular: reporte de un caso / Cutaneous tuberculosis in ear auricle: a case report

RESUMEN La tuberculosis cutánea representa menos del 2% de todos los casos de la infección por Mycobacterium tuberculosis. Su baja prevalencia, asociada a la amplia variedad en la presentación clínica de las lesiones, dificulta y retrasa el diagnóstico y, por tanto, el inicio del tratamiento. El siguiente es el caso de una paciente de 80 años, con una lesión ulcerada, crónica, en pabellón auricular izquierdo, con evolución tórpida y pobre respuesta al manejo farmacológico instaurado; con biopsia de piel que mostró reacción inflamatoria crónica y presencia de bacilos ácido-alcohol resistentes.

ABSTRACT Cutaneous tuberculosis represents less than 2% of all cases of infection with Mycobacterium tuberculosis. Its low prevalence, associated with a wide variety in clinical presentation of the lesions, hinders and delays the diagnosis and, thus, treatment initiation. The following is the case of an 80-years old, female patient with an ulcerated, chronic lesion in the left ear auricle, with a torpid evolution and poor response to established pharmacological management; with a skin biopsy that showed chronic inflammatory reaction and the presence of acid-fast bacilli.

A quantitative model for dermal infection and oedema in BALB/c mice pinna.

BACKGROUND: Pharmaceutical industry demands innovation for developing new molecules to improve effectiveness and safety of therapeutic medicines. Preclinical assays are the first tests performed to evaluate new therapeutic molecules using animal models. Currently, there are several models for evaluation of treatments, for dermal oedema or infection. However, the most common or usual way is to induce the inflammation with chemical substances instead of infectious agents. On the other hand, this kind of models require the implementation of histological techniques and the interpretation of pathologies to verify the effectiveness of the therapy under assessment. This work was focused on developing a quantitative model of infection and oedema in mouse pinna. The infection was achieved with a strain of Streptococcus pyogenes that was inoculated in an injury induced at the auricle of BALB/c mice, the induced oedema was recorded by measuring the ear thickness with a digital micrometer and histopathological analysis was performed to verify the damage. The presence of S. pyogenes at the infection site was determined every day by culture. RESULTS: Our results showed that S. pyogenes can infect the mouse pinna and that it can be recovered at least for up to 4 days from the infected site; we also found that S. pyogenes can induce a bigger oedema than the PBS-treated control for at least 7 days; our results were validated with an antibacterial and anti-inflammatory formulation made with ciprofloxacin and hydrocortisone. CONCLUSIONS: The model we developed led us to emulate a dermal infection and allowed us to objectively evaluate the increase or decrease of the oedema by measuring the thickness of the ear pinna, and to determine the presence of the pathogen in the infection site. We consider that the model could be useful for assessment of new anti-inflammatory or antibacterial therapies for dermal infections.

Intralesional triamcinolone injections for the treatment of preauricular sinus infections.

OBJECTIVES: The aim of this study is to confirm the effect of adjuvant intralesional triamcinolone acetonide injections (TRIAM) for the treatment of an infected preauricular sinus (PAS). METHODS: The medical charts of 103 patients diagnosed with PAS from March 2013 to December 2015 were reviewed and documented. The mean duration of treatment and postoperative follow-up period were compared between patients who received TRIAM and patients who received conventional treatment. RESULTS: Fifteen patients received TRIAM. The mean duration of treatment was 12.5±11.0days in patients treated with TRIAM, which was significantly shorter than patients without TRIAM (25.5±25.7days, p=0.010). In addition, the percentage of patients experiencing early recovery (within 10days) was 4.15 times higher with TRIAM (95% confidence interval: 1.07-16.13, p=0.040). The mean postoperative follow-up period revealed a similar tendency; patients treated with TRIAM required a shorter follow-up period (8±2.6days) than patients not treated with TRIAM (13.5±7.4days). However, this difference was not significant (p=0.242). CONCLUSION: Although the sample was small, patients with PAS infections who were treated with TRIAM as an adjuvant therapy required a significantly shorter treatment duration than patients receiving conventional treatment alone. This finding suggests a beneficial effect of TRIAM for the short-term control of PAS infections. Clinicians should consider TRIAM as an adjuvant treatment option.

A case of chromoblastomycosis by Fonsecaea nubica indicating a possible insect route of transmission.

A first auricular case of chromoblastomycosis due to Fonsecaea nubica is reported in a 42-year-old Chinese male. He presented a slightly verrucous, erythematous plaque on his right auricle which had gradually extended over a 10-year period, and the patient reported a history of dog flea sting before onset of the lesions. Diagnosis was based on histopathological and mycological examination of clinical samples, which revealed muriform cells. Identification of the aetiological agent was assessed by morphological characteristics and confirmed at species level by sequencing of the rDNA internal transcribed spacer (ITS). The patient showed marked clinical improvement after 3 months combination therapy with itraconazole and terbinafine. The possible mode of transmission of auricular chromoblastomycosis is discussed.

[Tuberculous granuloa of left auricle: case report].

A femail patient was presented to our department for a dark red painless mass in the left auricle, which has progressively enlarged for one year. Pathological examination revealed granuloma change. Mycobacterium tuberculosis DNA test was positive. Tuberculin test revealed strong positive reaction. This case was diagnosed as tuberculous granuloma.

Sporotrichosis in an unusual location--Case report.

Sporotrichosis is the most common subcutaneous mycosis. It is caused by the dimorphic fungus Sporothrix schenckii, and the infection is usually acquired by traumatic inoculation. We describe a case of sporotrichosis in an uncommon location with an unusual mode of transmission. A 49-year-old female patient who lived in an urban area of Rio de Janeiro presented with involvement of the left ear. No history of contact with soil, plants or animals was elicited. The suspected source of infection was a pair of handmade wooden earrings. The delay in the diagnosis and treatment resulted in higher morbidity, unsightly scarring and loss of ear lobe.

Sporotrichosis in an unusual location - Case report

Sporotrichosis is the most common subcutaneous mycosis. It is caused by the dimorphic fungus Sporothrix schenckii, and the infection is usually acquired by traumatic inoculation. We describe a case of sporotrichosis in an uncommon location with an unusual mode of transmission. A 49-year-old female patient who lived in an urban area of Rio de Janeiro presented with involvement of the left ear. No history of contact with soil, plants or animals was elicited. The suspected source of infection was a pair of handmade wooden earrings. The delay in the diagnosis and treatment resulted in higher morbidity, unsightly scarring and loss of ear lobe.

Pinna abscesses: can we manage them better? A case series and review of the literature.

Suppurative perichondritis of the pinna is a serious condition with potentially long-term cosmetic sequelae. Literature regarding the optimal treatment of these abscesses is scarce with most case series containing low numbers. This work reports the largest series from the UK to date; along with a review of recent literature. A 10-year retrospective review of case notes was undertaken. Demographic data, interventions and microbiology results were recorded along with outpatient descriptions of cosmetic outcomes. 20 patients were identified with male:female ratio of 4:1. Average patient age was 25.3 years (range 8-65). Average duration of symptoms prior to being seen by the ENT department was 9.95 days with an average length of stay in hospital of 2.5 days. 80% of patients had a surgical intervention performed. The commonest organism grown on microbiological culture was pseudomonas (33%). Of patients who attended follow-up, 28.6% had residual deformity. All of these had undergone surgical drainage of the abscess. Residual deformity was associated with longer time before presentation, piercing of the cartilage and a growth of pseudomonas. Prompt surgical management and appropriate antibiotic regimens to cover pseudomonas are the cornerstones of treatment in the event of pinna abscess formation.

Primary cutaneous tuberculosis of the pinna: an unusual presentation.

Cutaneous tuberculosis is an uncommon form of extra-pulmonary tuberculosis. A young female presented with chronic, non-healing ulceration involving the left pinna. Serology and skin biopsy suggested tuberculosis. Anti-tubercular therapy resulted in complete resolution of lesions. The recent increase in tuberculosis has led to myriad forms of the disease which often mimic non-specific dermatitis in morphology. The diagnostic dilemma encountered in such clinical settings has prompted us to present this unusual case. On review of literature, we could find only three case reports of ulcerative form of primary tuberculosis of pinna.

Scabies mites alter the skin microbiome and promote growth of opportunistic pathogens in a porcine model.

BACKGROUND: The resident skin microbiota plays an important role in restricting pathogenic bacteria, thereby protecting the host. Scabies mites (Sarcoptes scabiei) are thought to promote bacterial infections by breaching the skin barrier and excreting molecules that inhibit host innate immune responses. Epidemiological studies in humans confirm increased incidence of impetigo, generally caused by Staphylococcus aureus and Streptococcus pyogenes, secondary to the epidermal infestation with the parasitic mite. It is therefore possible that mite infestation could alter the healthy skin microbiota making way for the opportunistic pathogens. A longitudinal study to test this hypothesis in humans is near impossible due to ethical reasons. In a porcine model we generated scabies infestations closely resembling the disease manifestation in humans and investigated the scabies associated changes in the skin microbiota over the course of a mite infestation. METHODOLOGY/PRINCIPAL FINDINGS: In a 21 week trial, skin scrapings were collected from pigs infected with S. scabies var. suis and scabies-free control animals. A total of 96 skin scrapings were collected before, during infection and after acaricide treatment, and analyzed by bacterial 16S rDNA tag-encoded FLX-titanium amplicon pyrosequencing. We found significant changes in the epidermal microbiota, in particular a dramatic increase in Staphylococcus correlating with the onset of mite infestation in animals challenged with scabies mites. This increase persisted beyond treatment from mite infection and healing of skin. Furthermore, the staphylococci population shifted from the commensal S. hominis on the healthy skin prior to scabies mite challenge to S. chromogenes, which is increasingly recognized as being pathogenic, coinciding with scabies infection in pigs. In contrast, all animals in the scabies-free cohort remained relatively free of Staphylococcus throughout the trial. CONCLUSIONS/SIGNIFICANCE: This is the first experimental in vivo evidence supporting previous assumptions that establishment of pathogens follow scabies infection. Our findings provide an explanation for a biologically important aspect of the disease pathogenesis. The methods developed from this pig trial will serve as a guide to analyze human clinical samples. Studies building on this will offer implications for development of novel intervention strategies against the mites and the secondary infections.

Dolor e inflamación del pabellón auricular / Pain and inflammation of the pinna

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Cutaneous tuberculosis of the pinna: a report of two cases.

BACKGROUND: Cutaneous tuberculosis (TB) is less common than other forms of TB but accounts for 1.5% of all cases of extrapulmonary TB. The source of mycobacterial infection and the immune status of the host determine the presentation of any of a wide spectrum of clinical manifestations. Lupus vulgaris (LV) is a post-primary, paucibacillary form of TB caused by hematogeneous, lymphatic, or contiguous spread from elsewhere in the body. METHODS: We report two recent cases of LV in women presenting with the exclusive involvement of the ear lobe. In Patient 1, clinical presentation appeared as an apparently benign chronic eczematous process. In Patient 2, it appeared as a fulminant ulceronecrotic process. Both women were immunocompetent, and neither had a personal or family history of TB. RESULTS: Both patients were diagnosed with LV and treated with standard antitubercular therapy (ATT). In both patients, mycobacterial culture showed growth of Mycobacterium tuberculosis sensitive to streptomycin, rifampicin, and ethambutol. CONCLUSIONS: Lupus vulgaris is the most common form of cutaneous TB. It is important to diagnose LV because it can result in chronic disfigurement and because 10-20% of LV patients have active pulmonary TB or TB of the bones and joints. In addition, longstanding LV is known to lead to the development of squamous cell carcinoma, which can be avoided by early diagnosis and treatment with ATT.

Caracterização da microbiota auricular de cutias (Dasyprocta aguti) criadas em cativeiro / Characterization of auricular natural microbiota from captive agoutis (Dasyprocta aguti)

The aim of this study was to identify the aerobic bacteria of the auricular natural microbiota from healthy agoutis (Dasyprocta aguti Linnaeus, 1758). In the total, 48 agoutis were used in this experiment, being 32 adults and 16 puppies (both groups divided into equal parts between males and females). The animals were raised under captive conditions, in the Brazilian Semiarid. From each animal, a sample of auricular secretion was collected from each auricular pinna and processed for microbiological analyses. A total of 96 samples were collected and analyzed by colony macroscopic format, cytology and by biochemistry proofs with the objective of isolate and identify the microorganisms. The main bacteria found were Staphylococcus spp. (47.26%), Streptococcus spp. (12.80%), Bacillus spp. (22.73%) and Corynebacterium spp. (17.30%). As conclusion, the most frequent bacteria in auricular pinna of healthy agoutis are Gram-positive cocci and rods, similarly to found in some pets.

O presente trabalho teve por objetivo identificar as principais bactérias aeróbias que compõem a microbiota natural do pavilhão auricular de cutias hígidas. Para tanto, foram utilizadas 48 cutias, criadas em cativeiro sob as condições Semiáridas do Nordeste Brasileiro. Esses animais foram distribuídos nas categorias de adultos (N=32) e filhotes (N=16), e, em ambas, distribuídos igualmente entre machos e fêmeas. Através de um swab, em cada animal coletou-se de cada orelha a secreção presente na superfície do pavilhão auricular dos animais, totalizando 96 amostras. Este material foi refrigerado, e encaminhado ao laboratório para a realização das análises microbiológicas (macroscopia das colônias, citologia e provas bioquímicas), com o intuito de isolar e identificar os microrganismos. Os principais microrganismos isolados foram Staphylococcus spp. (47,26%), Streptococcus spp. (12,80%), Bacillus spp. (22,73%) e Corynebacterium spp. (17,30%). Verificou-se também que não houve diferença entre adultos e filhotes em relação aos microrganismos retrocitados. Assim, as bactérias residentes do pavilhão auricular de cutias hígidas são essencialmente cocos e bacilos gram-positivos, similarmente ao encontrado em pequenos animais domésticos.