Treatment of ligneous conjunctivitis with amniotic membrane transplantation and topical cyclosporine.

Ligneous conjunctivitis (LC) is a rare form of bilateral chronic recurrent disease in which thick membranes form on the palpebral conjunctiva and other mucosal sites. We report the clinical features and describe the management of two cases. Case 1 was an 8-month-old patient with bilateral membranous conjunctivitis. Case 2 was a 5-year-old patient with unilateral membranous conjunctivitis, esotropia, mechanical ptosis and complicated cataract, and had been treated with a number of medications. Histological investigation of the membrane in both cases showed LC. Treatments with amniotic membrane transplantation and institution of topical cyclosporine have shown good response. There has been complete resolution of the membranes with no recurrence at the end of 40- and 28-month follow-ups, respectively. No treatment related side effects were seen. Thus, it appears that amniotic membrane transplantation and topical cyclosporine are effective alternatives for the treatment of LC.

Valor de la utilización de espaciadores de cemento y aloinjerto con antibiótico para reconstruir defectos óseos infectados: estudio experimental en conejos / Value of using antibiotic-loaded cement spacers and allograft to reconstruct infected bone defects: experimental study in rabbits

Introducción: El objetivo de este trabajo fue evaluar diferentes formas de tratamiento en fracturas expuestas con pérdida ósea e infectadas en conejos. Materiales y métodos: Se realizó un estudio experimental utilizando 25 conejos adultos. En todos se reprodujo una fractura expuesta mediodiafisaria de fémur en la cual se inoculó Staphylococcus aureus. Luego, en forma aleatoria, en el grupo I no se realizó tratamiento (grupo de control), en el grupo II se colocó polimetilmetacrilato con gentamicina y vancomicina en el foco de fractura asociado a antibiótico por vía sistémica, en el grupo III se colocó polimetilmetacrilato sin antibiótico en el foco de fractura asociado a antibiótico por vía sistémica, en el grupo IV se colocó aloinjerto crioconservado molido de hueso con vancomicina en el foco de fractura asociado a antibiótico por vía sistémica y, en el grupo V, se administró sólo antibiótico por vía sistémica. Se realizó la evaluación histológica de la seudomembrana formada alrededor del cemento con antibiótico y sin él. Resultados: En el grupo I se obtuvieron cinco cultivos positivos para S. aureus, en el grupo II y IV cinco cultivos negativos en cada uno, en el grupo III cuatro cultivos negativos y un cultivo positivo, y en el grupo V dos cultivos negativos y tres cultivos positivos. Los resultados de la evaluación histológica fueron similares y mostraron que la presencia de antibiótico en el cemento no alteró las características histológicas de la seudomembrana. Conclusiones: Cuando se decide hacer la reconstrucción de la fractura en un tiempo la asociación de antibiótico al injerto de hueso ayuda a prevenir la infección; si se decide realizar la reconstrucción en dos tiempos la colocación de un espaciador de polimetilmetacrilato con antibiótico en el defecto óseo es el método de elección.

Background: The purpose of this experimental study was to evaluate in rabbits different types of treatment in infected open fractures with bone loss.Methods: Twenty five adult rabbits were included in the study. A mid-diaphyseal open fracture of the femur was reproduced in all of them, and subsequently contaminated with Staphylococcus aureus. Group I was not treated (control group). In Group II, polymethylmethacrylate with gen-tamicin and vancomycin was placed in the fracture site, associated to systemic antibiotics. Group III was given polymethylmethacrylate without antibiotic in the fracture site, associated to systemic antibiotics. Group IV received fresh frozen morselized allograft with vancomycin in the fracture site, associated to systemic antibiotics. Group V only received systemic antibiotics. The pseudomembrane formed around the cement was histologically evaluated.Results: In Group I, five cultures were positive for Staphylococcus aureus. In Groups II and IV, all cultures were negative. In Group III, four cultures were negative and one was positive. In Group V, two were negative and three were positive. The histological results were similar in the groups in which cement had been used; this showed that the addition of antibiotics to the cement does not alter the histological characteristics of the pseudomembrane.Conclusions: For primary open fracture reconstruction, the addition of antibiotics to the bone graft helps prevent infection; and if staged reconstruction is prioritized, placing a polymethylmethacrylate spacer with antibiotics in the defect during the first stage should be considered.

Fibrinogen binds to nontoxigenic and toxigenic Corynebacterium diphtheriae strains

The production of fibrinous exudates may play an important role in determining the outcome of bacterial infection. Although pseudomembrane formation is a characteristic feature of diphtheria, little is known about the fibrinogen (Fbn)-binding properties of Corynebacterium diphtheriae strains and the influence of the gene that codes for diphtheria toxin (tox gene) in this process. In this study we demonstrated the ability of C. diphtheriae strains to bind to Fbn and to convert Fbn to fibrin. Bacterial interaction with rabbit plasma was evaluated by both slide and tube tests. Interaction of microorganisms with human Fbn was evaluated by both enzyme linked immunosorbent assay (ELISA) and fluorescein isothiocyanate-conjugated (FITC) Fbn binding assays. Nontoxigenic and toxigenic strains formed bacterial aggregates in the presence of plasma in the slide tests. The ability to convert Fbn to a loose web of fibrin in the plasma solution in the tube tests appeared to be a common characteristic of the species, including strains that do not carry the tox gene. Fbn binding to C. diphtheriae strains occurred at varying intensities, as demonstrated by the FITC-Fbn and ELISA binding assays. Our data suggest that the capacity to bind to Fbn and to convert Fbn to fibrin may play a role in pseudomembrane formation and act as virulence determinants of both nontoxigenic and toxigenic strains.

Papel das hemaglutininas 67-72p de Corynebacterium diphtheriae na ligação a proteínas plasmáticas, superfícies celulares, invasão e indução de apoptose / Role of haemagglutinins 67-72p de Corynebacterium diphtheriae in binding to plasma proteins, cell surfaces, invasion and induction of apoptosis

Corynebacterium diphtheriae pode ser isolado tanto de quadros de difteria clássica, quanto de infecções sistêmicas, como endocardite. O fibrinogênio (Fbn) e a fibronectina (Fn) são glicoproteínas presentes na matriz extracelular de tecidos conjuntivos. A influência destas proteínas na patogênese das infecções locais e invasivas causadas por C. diphtheriae é objeto de estudo devido ao fato do bacilo diftérico poder ser encontrado em lesões nas quais o Fbn e a Fn são predominantes, incluindo a pseudomembrana diftérica e vegetações cardíacas presentes na endocardite infecciosa. São crescentes as evidências de que o C. diphtheriae pode, além de aderir, ser internalizado por células em cultura. No presente estudo, investigou-se a participação de C. diphtheriae e das proteínas de superfície 67-72p na aderência à Fn e ao Fbn de plasma humano e a eritrócitos. A aderência às células HEp-2 e internalização também foram analisadas. A participação de 67-72p nos mecanismos de morte celular foi avaliada através das colorações por Azul de Tripan e 4'6-diamidino-2-fenil indol (DAPI), pelo ensaio de redução utilizando dimetil-tiazol-difenil tetrazólio (MTT) e por citometria de fluxo. As 67-72p foram extraídas da superfície da amostra toxigênica C. diphtheriae subsp. mitis CDC-E8392 através de processos mecânicos e precipitação com sulfato de amônio saturado. Análises por SDS-PAGE e immunoblotting detectaram a presença das bandas protéicas de 67 e 72kDa nas amostras toxinogênicas e atoxinogênicas analisadas, as quais pertenciam aos biotipos fermentador e não fermentador de sacarose. C. diphtheriae foi capaz não só de formar agregados na presença de plasma de coelho, mas também de converter Fbn em fibrina independentemente da presença do gene tox. No entanto, a amostra atoxinogênica ATCC 27010 (tox-) foi menos aderente ao Fbn do que a homóloga ATCC 27012 (tox+). A interação bacteriana com eritrócitos foi inibida somente pela Fn. Ligações entre Fn e/ou Fbn com 67-72p foram ...

Corynbacterium diphtheriae have been isolated from classical diphtheria and systemic infections such as endocarditis. Fibrinogen (Fbn) and fibronectin (Fn) are high molecular-weight glycoproteins that may be found in extracellular matrix of connective tissues. Their influence in the pathogenesis of local and in invasive C. diphtheriae infection is object of interest due to the fact that diphtheria bacilli is recovered from lesions where such proteins are predominant, including pharyngeal pseudomembrane and valve heart vegetations in infectious endocarditis. There is growing evidence that C. diphtheriae may adhere to and be internalized by cells in culture. The present study investigated the participation of C. diphtheriae strains and 67-72p, a surface protein, in adherence to human plasma Fn, Fbn, erityrocytes, adherence to and internalization by HEp-2 cells. The participation of 67-72p in promoting cell death was evaluated by the Trypan blue, DAPI staining methods, methylthiazole tetrazolium (MTT) reduction assay and flow cytometry. The 67-72p was extracted from C. diphtheriae subsp. mitis CDC-E8392 toxigenic strain, by mechanical process and ammonium sulfate fractionation. SDS-PAGE and immunoblotting analysis detected the polypeptide bands of 67 and 72 kDa in all toxigenic and nontoxigenic strains from both sucrose-fermenting and non-fermanting biotypes. Diphtheria bacilli were capable to both form bacterial aggregates in rabbit plasma and to convert Fbn to fibrin independently to the presence of tox gene, albeit the ATCC 27010 (tox-) strain was less adherent to Fbn than the paental strain ATCC 27012 (tox+). Bacteria-erythrocytes interaction was inhibited only ...

A Histopathologic Study of the Pseudomembranes harvested during Revision Total Hip Arthroplasty / 대한정형외과학회잡지

PURPOSE: To analyze the results of the foreign body reaction to polyethylene, polymethylmethacrylate, and metal debris and effect on bone by comparing histopathologic finding of pseudomembrane (interface membrane) which was obtained from failed cemented or cementless THA by aseptic loosening. MATERIALS AND METHODS: Of total 50 cases, we analyzed results between 25 cases of cemented THA and 25 cases of cementless THA. Follow-up period between primary and revision THA was average 8 years 5 months. Tissue specimens were harvested, stained with Hematoxylin-Eosin, and examined by light microscope. Histologic study of various items was done. RESULTS: The fibrous membrane between bone-to-cement or bone-to-metal could be roughly divided into three distinct histological layers in cross section histopathology. These tissues were characterized by histiocytes, infiltration of foreign body giant cells and fibrosis in all specimens, and infiltration of lymphocytes and plasma cells was relatively rare, and aggregation of polymorphonuclear leukocytes was invisible. CONCLUSION: Although there were no significant differences in histologic findings between the regions of ten tissue specimens, there was significant difference between the degree of polyethylene or cement debris in numbers and the degree of foreign body reaction associated with increased infiltrations of giant cells, and foreign body reaction to polyethylene debris seems to be main cause of aseptic loosening of prosthesis.

Tracheobronchial Aspergillosis An autopsy case report

Tracheobronchial aspergillosis is an unusual form of invasive aspergillosis characterized by noninvasive or only superficially invasive tracheobronchitis with a propensity for dissemination. We report a two-year-old male who suddenly died of respiratory failure. Postmortem examination revealed a pseudomembrane covering the mucosa of larynx, trachea and bronchial tree of both lungs. This pseudomembrane was composed predominantly of Aspergillus hyphae. There was transmural necrotizing bronchitis with fungal invasion to the narrow zone of peribronchial tissue, and dissemination to the stomach and kidney. This form of pulmonary aspergillosis had not been reported in this country.