The role of serum calcium in the development of the acute red eye in chronic renal failure.

In patients with chronic renal failure treated by long-term dialysis, inflammatory reactions occasionally develop in the bulbar conjunctiva; the episcleral tissue is only rarely involved. Diffuse congestion of both the conjunctiva and episclera was present in 5.3% of our patients and was associated with a sudden, marked rise in serum calcium. Histopathological examination suggests that this form of hyperemia, clinically preceded by a marked shedding of calcific precipitates, is the result of a neurogenic-driven inflammatory reaction in which mast cell degranulation is mediated by the axon reflex. Focal hyperemia associated with elastosis ("pingueculitis") was present in 6.7% of the patients. This type of hyperemia was observed after an extended period of increasing levels of BUN and seemed independent of both serum calcium and phosphorus. Diffuse hyperemia of the conjunctiva, being clinically distinctly different from the combined diffuse conjunctival and episcleral hyperemia, was also observed in 6.7%. Diffuse conjunctival hyperemia seemed to be associated with low BUN. Here, again, there was no association with serum calcium and phosphorus levels.

Rapid progression of band-shaped keratopathy with early central localisation in a patient on chronic dialytic treatment.

This clinical study reports on an unusual start of a band-shaped keratopathy in a patient with diabetic nephropathy on dialytic treatment. The earliest corneal manifestations were centrally located small greyish-white disc-shaped lesions evenly distributed in the interpalpebral area in the left eye. Later a typical peripheral band-shaped keratopathy developed. In the course of the observation period the peripheral keratopathy rapidly spread towards the centre, finally resulting in a complete band-shaped keratopathy in which only the most central original disc-shaped lesions could be identified. Serum calcium and phosphorus concentrations were markedly elevated at the time of the progression of the band-shaped keratopathy but no tertiary hyperparathyroidism was present.

Diffuse and focal hyperaemia of the outer eye in patients with chronic renal failure.

In 8 of 57 patients with chronic renal failure that all had deposition of calcium salts in the limboconjunctival area, a focal hyperaemia of the conjunctiva was observed. This focal hyperaemia developed gradually around one or more greyish, slightly elevated, areas situated in the bulbar conjunctiva in the interpalpebral fissure. Clinically these lesions are very much alike inflamed pingueculae. Three patients showed a diffuse inflammatory reaction of the eye that was characterized by a waxy red episcleral and conjunctival hyperaemia extending beyond the palpebral fissure. The average value of the serum calcium concentration in these patients was particularly high and statistically significantly higher than in patients with calcification but without inflammatory signs and also higher than in patients that showed focal hyperaemia. In addition to the focal hyperaemia and the diffuse hyperaemia, we observed another diffuse hyperaemia located principally in the conjunctival tissue. This conjunctival redness often followed the focal hyperaemia associated with pingueculae or preceded the more acute fiery red episcleral hyperaemia, but it could also be present in isolation.

The red eye of renal failure: a crystal induced inflammation?

Of 57 patients with chronic renal failure and calcification of the anterior membranes of the eye eight developed inflammatory reactions, clinically indistinguishable from pingueculitis. In three patients an acute inflammatory reaction of the episcleral tissue and the conjunctiva over it developed which we considered to represent the red eye of renal failure. In these patients massive shedding of calcium phosphate salts was clinically evident. Histopathologically in all these patients calcific deposits were observed. Although sporadically polymorphonuclear leucocytes were present in the inflamed tissues we could not demonstrate crystal phagocytosis. We believe that in the red eyes in renal failure and, more specifically, in the red eyes of renal failure a crystal induced inflammatory mechanism is not operative.

Metastatic or dystrophic conjunctival calcification in renal failure?

In renal failure the incidence of pingueculae is significantly higher than in a comparable control group but there is no evidence that the calcific precipitation in renal failure is of a dystrophic nature. The lime salts are not located within the area of elastotic degeneration, a prerequisite for dystrophic degeneration. Moreover there is no association between the magnitude of the conjunctival degeneration and the degree of calcification. This makes it likely that the calcium precipitates represent metastatic calcification even though admittedly support for this assumption is tenuous.

Changes in the diagnostic parameters during keratoconjunctivitis sicca therapy.

In 35 patients with mild, moderate and severe keratoconjunctivitis sicca, an association was found between treatment effect, break-up time value and Rose bengal score. Neither of these tests, used separately, was successful as a clinically valuable predictor of treatment effect as the scatter, in score points, was too large. Analysed together, however, as in a partial regression analysis, an adequate prediction is possible, which is clinically of some value.

A double-blind crossover study comparing sodium cromoglycate eye drops with placebo in the treatment of chronic conjunctivitis.

In a placebo controlled double-blind crossover study, 60 patients with chronic non-infections conjunctivitis were treated for 4 weeks with either sodium cromoglycate eye drops or with placebo followed by 4 weeks on the alternative treatment. The dose was one drop into each eye 4 times daily. The scores for a number of symptoms and signs were significantly lower after 4 weeks sodium cromoglycate treatment than after similar placebo treatment. In both the patients' and clinician's opinion significantly more patients responded to the active treatment than to the placebo treatment. At the end of the trial clinician recorded more preferences for sodium cromoglycate (27) than for placebo (9), and the difference was highly significant (P less than 0.01). No side effects were reported during the trial.

The effect of calcium dobesilate on albumin leakage of the conjunctival vessels.

Calcium dobesilate significantly reduced the leakage of serum albumin in the tear fluid in patients with chronic inflammatory reactions of the conjunctiva. In the majority of cases reduction of serum albumin concentration in the tear-fluid was treatment related. The marked increase in tear albumin concentration after treatment, found in two cases, was caused by a sharp increase in the inflammatory reaction due to an exacerbation of the underlying disease during the trial period. No relation was found between improvement of symptoms as reported by the patients and alterations in serum albumin concentrations.