Corneal deposits associated with flecainide

Oligosymptomatic cornea verticillata in a heterozygote for Fabry disease: a novel mutation in the alpha-galactosidase gene

BACKGROUND

Fabry disease is an X-linked genetic disorder involving sphingolipid catabolism, which is caused by lysosomal alpha-galactosidase A deficiency. Ophthalmological findings such as corneal and lens opacities and conjunctival and retinal vessel abnormalities can be the only and/or the first recognizable symptoms, especially in heterozygous females.

METHODS

We report on a 34-year-old German woman with cornea verticillata. The alpha-galactosidase A activity was determined in leukocytes using a fluorescence substrate, and the sequence analysis of the alpha galactosidase A gene was performed with genomic DNA.

RESULTS

The alpha-galactosidase A activity in leukocytes was significantly low (0.24 nmol/min/mg protein; normal range, 0.4-1.2), which is compatible with a heterozygote for Fabry disease. The following sequence analysis revealed a heterozygous transition in position IVS5 + 2 T > C. Transition of thymine (T) to cytosine (C) affects the donor splice motive of exon 5 and most probably leads to an aberrant splicing procedure of the alpha-galactosidase A gene.

CONCLUSION

Our case emphasizes the importance of ophthalmological findings in Fabry disease. The subsequent biochemical and molecular analysis provides a secure diagnosis of female carriers of Fabry disease.

Adverse ocular effects of flecainide

PURPOSE

To study if flecainide has ocular adverse effects.

METHODS

Both eyes of 38 flecainide medicated patients were thoroughly examined including colour vision, contrast sensitivity and visual fields.

RESULTS

10.5% of the patients had blurred vision on lateral gaze lasting for a couple of seconds. Small corneal deposits were found in 14.5% of the patients. All visual function tests were normal.

CONCLUSION

Flecainide seems to be a safe drug with minimal ocular adverse effects.

Adverse effects of class I antiarrhythmic drugs

Class I antiarrhythmic drugs are characterised by their ability to block the fast inward sodium current in cardiac muscle tissue. However, at the same time, they can be responsible for various effects involving other organs and systems. Although some of these effects can be helpful in specific situations, most of them, such as their pro-arrhythmic propensity, are deleterious. Some of the adverse effects of class I antiarrhythmic drugs are directly linked to sodium-channel blockade (conduction disorders haemodynamic perturbations, and digestive and neurological effects), while others are linked to other specific pharmacological properties (e.g. atropinic, or alpha- or beta-adrenergic blockade) or to nonspecific properties (idiosyncratic hypersensitivity, and haematological, dermatological or hepatic reactions). Other adverse effects are associated with complex interactions between class I antiarrhythmics and individual predisposing factors, trigger mechanisms and physiological factors (including concomitant drug treatment). These numerous variations and interactions within a specific environment and underlying disorder might be of pharmacological or/and pharmacokinetic origin, making analysis of the true liability of the class I drugs very difficult when adverse effects occur.

Immunoglobulins in granular corneal dystrophy Groenouw type I

Three patients with granular corneal dystrophy Groenouw type I underwent corneal grafting, and cryostat sections of the corneal buttons were examined immunohistochemically for immunoglobulins. Positive results were obtained for IgG, Kappa-, and Lambda chains with immunofluorescence technique. The reactions were seen exclusively in the same localizations as the Masson trichrome positive deposits.