Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0022568 (keratitis)
 5,133 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Eleven corneal specimens from nine patients with Salzmann's nodular degeneration of the cornea, together with all available clinical information, were collected for this study. The specimens were examined by light and electron microscopy. An antecedent keratitis was diagnosed by history and microscopic findings in every case. The corneal epithelium showed degenerative changes, its thickness varied, and in nodular areas it often consisted of only a single layer of flattened epithelial cells by light microscopy. Bowman's membrane was missing over the nodules, and in this zone there was excessive secretion of a basement membrane-like material. Hyaline degeneration of collagen, cellular debris, and electron-dense hyaline deposits were seen in the collagen of the nodules. The number of fibrocytes in the nodules varied from many that were active to a few that were degenerating. External irritation because of poor epithelial protection was interpreted as a causative factor, although other tissue repair mechanisms may also have played a role.
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PMID:Salzmann's nodular degeneration of the cornea. 4 19

A 59-year-old woman with superficial punctate keratitis of Thygeson was observed for 14 years. The patient was treated intermittently with topical corticosteroids and artificial tears. Immediate symptomatic relief was followed by multiple recurrences and exacerbations. This case was atypical because of its prolonged clinical course and development of permanent, subepithelial corneal scarring, and elevated lesions resembling Salzmann's nodular degeneration.
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PMID:Superficial punctate keratitis of Thygeson associated with scarring and Salzmann's nodular degeneration. 43 89

From Dimmer's original description of 4 cases of keratitis, it would seem that what is now known as a keratitis nummularis (Dimmer), is not one specific corneal disease but a heterogeneous group of diseases. Salzmann demonstrated in certain cases a clear relationship between it and herpetic keratitis and its corneal complications. Later authors have not convincingly differentiated KND from herpetic keratitis, as no tests have been performed to determine corneal sensitivity. Pillat, who did use the criterion of normality of corneal sensitivity for the diagnosis of KND, was unable to differentiate KND adequately from the sequelae of adenovirus keratitis. Nummular keratitis (Dimmer) does not play a diagnostic part in ophthalmology, as we are not dealing with a nosological entity.
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PMID:[Dimmer's keratitis nummularis, a doubtful disease]. 664 57

Recurrent corneal erosions (RCE) are common. They are characterised by repeated episodes of pain, difficulty in opening the eyes, watering, and photophobia resulting from poor epithelial adhesion. In the majority of patients with RCE, trauma is the initiating factor. Epithelial, stromal, and endothelial corneal dystrophies have all been described in association with RCE. Other causes that may lead to RCE include chemical and thermal injuries, previous herpetic keratitis, meibomian gland dysfunction, ocular rosacea, diabetes mellitus, Salzmann's nodular degeneration, band keratopathy, previous bacterial ulceration, kerato-conjunctivitis sicca, and epidermolysis bullosa. The conditions that are associated with RCE can be either primary or secondary depending on whether the basement membrane complex abnormality is intrinsic or acquired. Primary types tend to be bilateral, symmetrical and develop in multiple corneal locations. The pathogenetic mechanism of this disorder is related to poor adhesion of the corneal epithelium to the underlying stroma. Excessive matrix metalloproteinase (MMP) activity may play a role in the pathogenesis. Although the majority of patients will respond to simple measures such as padding and antibiotic ointment, RCE resistant to simple measures require approaches that are more elaborate. The common goal of these approaches is to encourage proper formation of adhesion complexes between the epithelium and the stroma. The use of long-term contact lenses, autologous serum eye drops, botulinum toxin, induced ptosis, oral MMP inhibitors, diamond burr polishing of Bowman's membrane have been reported with varying degree of success in treating RCE. Anterior stromal puncture with insulin needles or Neodymium : aluminium-yttrium-garnet may enhance the epithelial adhesion to the basement membrane by scar formation and success rates of up to 80% have been reported in the treatment of recalcitrant RCE. Excimer laser photo-therapeutic keratectomy (PTK) is now a well-established treatment modality for RCE and is being used both safely and effectively. Partial ablation of Bowman's layer with PTK gives a smooth surface for the newly generating epithelium to migrate and form adhesion complexes. The pathogenesis, clinical features, and management options of this common disorder are discussed in this review article.
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PMID:Pathogenesis, clinical features and management of recurrent corneal erosions. 1757 Oct 89

Salzmann's nodular degeneration is a rare, noninflammatory, slowly progressive, degenerative condition. Bluish-white nodules raised above the surface of the cornea characterize it. It has usually developed in corneas with a history of phlyctenulosis, trachoma, vernal keratoconjunctivitis, measles, scarlet fever, and various other viral diseases. However, today the majority of cases have been seen without recognized previous keratitis. It is composed of dense irregularly arranged collagen tissue with hyalinization between epithelium and Bowman's layer or beyond. Manual removal, phototherapeutic keratectomy (PTK) with or without the use of topical mitomycin-C, lamellar or penetrating keratoplasty have been used in the treatment of this disease. Salzmann's nodular degeneration does not seem to consist of one clinical entity. In some cases, elevated and pannus-like tissue can be separated easily from the corneal surface leaving Bowman's layer almost untouched. In these eyes, subsequent PTK may be necessary to smooth the surface. Recurrences are rare in these eyes. In contrast, some eyes (often with major peripheral vascularization) are left with deep defects in Bowman's layer and superficial stroma after difficult mechanical removal of nodules. In these eyes, multiple masking/laser ablation procedures are mandatory to acquire a homogenous surface. In our experience, the required laser ablation depth is significantly greater and the best-corrected visual acuity to be expected is reduced in contrast to the eyes with easy removal of the nodules. In these eyes recurrences seem to occur more frequently after treatment. Of 35 eyes documented to have Salzmann's nodular degeneration during the last 15 years in our department, 22 needed PTK treatment. Visual acuity increased from 0.4 to 0.7 on average. As a routine, laser ablation should be combined with previous conventional removal of nodules and excessive pannus tissue. By doing so, lamellar and penetrating keratoplasty techniques are hardly ever required in those eyes.
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PMID:Salzmann's nodular degeneration of the cornea: a review and case series. 1616 Apr 90

So-called Salzmann's nodular degeneration has been given a misleading position in the systematics of ophthalmology. The majority of cases of Salzmann's nodular degeneration are in fact a clinical entity fulfilling the criteria of epithelial corneal dystrophy involving Bowman's layer. As with all epithelial dystrophies Salzmann's nodular degeneration recurs after surgical removal. An analysis of Salzmann's original paper discloses that the etiological postulates (severe preceding keratitis, especially phlyctenular keratitis) have never been substantiated by direct observation but only suspected by indirect histopathological circumstantial evidence. This has long lost credibility and should never have been taken for real evidence. However, degenerative types of Salzmann's nodular degeneration besides the dystrophic type still exist but the etiology and pathogenesis of these degenerative types have not yet been sufficiently described. No distinction has been made in studies of Salzmann's nodular degeneration up to now between dystrophic and degenerative types which could render such publications worthless on re-evaluation. While therapy of Salzmann's dystrophy is usually simple even after recurrence this may be different with the degenerative forms. The many questions and inconsistencies which have long been noted with "Salzmann's degeneration" as it has been misunderstood, can only be answered and solved if dystrophy and degeneration are investigated separately in future studies.
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PMID:[Salzmann's nodular degeneration. Mostly an epithelial corneal dystrophy]. 2305 42