muramidase and Corneal-Diseases

This paper considers the dubious role of asymptomatic marginal reduction of tear production in the aetiology of contact lens intolerance and how in the light of our present knowledge and the tests available it is difficult to identify such marginal underproduction of tears. Contact lenses have a possible therapeutic role in the management of established dry eyes with and without conjunctival scarring and destructive corneal changes. All soft contact lenses have been shown to lose a considerable percentage of their fully hydrated water content when put in any eye and the presence of a contact lens in an eye has been shown to increase tear evaporation, irrespective of evaporation from the contact lens. Soft contact lenses would appear to be able to withstand considerable dehydration and yet maintain their optical quality and in the eye with inadequate tears a lens of lower water content will remain hydrated to a reasonable extent for a longer period than one of a higher water content. Contact lenses may be necessary in the dry eye to provide an optical surface to the cornea when it is the site of destructive changes. In the case of the severely dry eye it may be necessary to use a silicone soft lens with no water content in order to obviate the problems of dehydration. There are considerable dangers in such eyes with and without conjunctival and corneal destructive changes and a decision to fit a lens should not be taken lightly and without adequate provision for close follow up.

Topics: Conjunctival Diseases; Contact Lenses; Contact Lenses, Hydrophilic; Corneal Diseases; Desiccation; Humans; Muramidase; Pemphigoid, Benign Mucous Membrane; Silicones; Tears; Time Factors; Visual Acuity; Xerophthalmia

To present a case of a corneoscleral juvenile xanthogranuloma (JXG) with diagnostically challenging features.. A 15-year-old boy's small corneoscleral mass of recent onset was examined histologically and immunohistochemically.. The biopsy had some superficially misleading histological and immunohistochemical features: S-100 positivity (however, observable in 30% of JXG lesions) and lack of Touton giant cells (often absent in early lesions). Most importantly, the histiocytes stained negatively for CD1a and strongly positively for both lysozyme and CD68 antigen.. JXG is a benign histiocytic disorder that usually appears early in childhood but is also encountered in 13%-18% of cases in the second decade. The histiocytes usually stain positively for CD68 and negatively for S-100 and CD1a. Correctly distinguishing JXG from the more aggressive spectrum of Langerhans cell diseases (100% have CD1a positivity) is essential for patient treatment.

Topics: Adolescent; Antigens, CD; Antigens, CD1; Antigens, Differentiation, Myelomonocytic; Corneal Diseases; Histiocytes; Humans; Male; Muramidase; S100 Proteins; Scleral Diseases; Xanthogranuloma, Juvenile

To investigate the effects of chronic smoking on the ocular surface and tear characteristics.. The Schirmer I-test, tear film break-up time, rose Bengal staining scores, impression cytology, tear lysozyme concentration, eye irritation symptoms, and eye irritation indices were determined for 44 eyes in 44 healthy, chronic smokers who had smoked six or more cigarettes per day for the previous year. Thirty-seven eyes in 37 healthy, non-smokers were assessed in the same masked manner for comparison. Cytological specimens were obtained from the temporal interpalpebral bulbar conjunctiva by 'impression' technique. Goblet cells were counted in the specimens obtained and squamous metaplasia was graded following epithelial cell morphology assessment.. In chronic smokers, we found decreased tear film break-up time (p=0.022) and tear lysozyme concentration (p=0.013), and increased Schirmer I-test values (p=0.047), squamous metaplasia scores (p=0.016), eye irritation scores (p<0.001) and eye irritation indices (p=0.013), as compared with the control group. There were no statistically significant differences in goblet cell counts (p=0.710) or rose Bengal staining scores (p=0.827).. These findings suggest that chronic smoking has a negative effect on the ocular surface and affects some tear characteristics. The chronic ocular irritative effects of cigarette smoking may lead to defects in ocular surface defence.

Topics: Adult; Cell Count; Chronic Disease; Conjunctival Diseases; Corneal Diseases; Epithelial Cells; Fluorescent Dyes; Goblet Cells; Humans; Metaplasia; Muramidase; Rose Bengal; Smoking; Staining and Labeling; Tears

Reticulohistiocytoma is a rare, benign histiocytic lesion usually occurring as an isolated skin nodule or as part of a systemic disorder known as "multicentric reticulohistiocytosis." The clinical and histopathologic findings of two women who presented with a single, painless mass localized to the cornea and limbus without skin lesions or systemic disease are reported. Histopathologically, the lesions were composed predominantly of large mononuclear and a few multinucleated cells with finely granular, "ground-glass" cytoplasm and large nuclei with prominent nucleoli. Immunohistochemical and electron microscopic studies conformed the histiocytic nature of these cells. Reticulohistiocytoma should be included in the differential diagnosis of epibulbar benign histiocytic lesions.

Topics: Adult; Chymotrypsin; Corneal Diseases; Female; Histiocytosis, Non-Langerhans-Cell; Humans; Immunoenzyme Techniques; Muramidase; Phosphopyruvate Hydratase; S100 Proteins; Scleral Diseases; Visual Acuity

The ocular findings in three brothers with Bruton's disease are reported. All three boys had purulent conjunctivitis, but the two older brothers also developed marked corneal scarring with visual impairment. Haemophilus influenzae was cultured from conjunctival swabs; it was resistant to neomycin but sensitive to chloramphenicol. Tear analysis showed that the three subjects had normal levels of lysozyme but no detectable IgA.

Topics: Agammaglobulinemia; Child; Chloramphenicol; Conjunctivitis, Bacterial; Corneal Diseases; Haemophilus Infections; Humans; Immunoglobulins; Infant; Male; Muramidase; Secretory Component; Tears

The mechanism of pathogenesis underlying the development of corneal lesions in measles was investigated in 125 children suffering from measles and 66 age- and sex-matched healthy controls. Forty age-matched children with bronchopneumonia were investigated on similar lines to delineate the role played by vitamin A and measles individually in the development of corneal lesions. The results indicate that the pathogenesis of corneal lesions in measles is indeed multifactorial. Vitamin A deficiency alone or measles keratitis per se may not explain the mechanism completely. The immunosuppression induced by the local proliferation of the measles virus in the eye might trigger the invasion of pathogenic microbes which damage the cornea. The structural integrity of the cornea is already compromised by vitamin A deficiency and lesions of measles keratitis.

Topics: Bronchopneumonia; Child; Cornea; Corneal Diseases; Eye; Humans; Immunoglobulin A, Secretory; Keratitis; Measles; Muramidase; Tears; Vitamin A