Primary local orbital amyloidosis: biochemical identification of the immunoglobulin light chain kappaIII subtype in a small formalin fixed, paraffin wax embedded tissue sample.

BACKGROUND: Amyloidosis refers to a heterogeneous group of disorders associated with the deposition of chemically distinct amyloid fibril proteins. Precise determination of chemical amyloid type has diagnostic, therapeutic, and prognostic relevance. Although immunohistochemical techniques are used routinely to determine the amyloid type, the results can be negative or inconclusive, so that biochemical characterisation is often required. The development and application of new biochemical microtechniques suitable for examination of extremely small tissue samples is essential for precise identification of the deposited amyloid proteins. AIMS: To investigate biochemically the amyloid proteins present in a formalin fixed paraffin wax embedded orbital tissue from a patient with localised orbital amyloidosis in whom immunohistochemistry was not helpful in the determination of amyloid type. METHODS: Extraction of amyloid proteins from fixed tissue and their identification was carried out by a recently developed microtechnique. An extremely small tissue sample was dewaxed and extracted with formic acid. The extracted material was analysed using electrophoresis, western blotting, and amino acid sequencing. RESULTS: Biochemical examination of the extracted proteins showed the presence of immunoglobulin (Ig) derived amyloid proteins, which were composed of the N-terminal fragments of the Ig light chain kappaIII subtype (AL-kappaIII) (16, 8, and 3 kDa). CONCLUSIONS: This is the first chemically proved AL case reported in association with primary localised orbital amyloidosis. The biochemical microtechnique used was useful in achieving a precise diagnosis of amyloid disease, in a case where the results of routine immunohistochemical examination of amyloid were inconclusive.

Metoprolol responding uveitis.

BACKGROUND: Noninfectious uveitis is usually managed by topical and systemic corticosteroids and in refractory cases by immunosuppressive drugs. OBJECTIVE: To describe a patient with noninfectious anterior and posterior uveitis, refractory to corticosteroids, and immunosuppressive therapy, which responded to systemic metoprolol. PATIENT AND METHODS: A 49-year-old patient was treated for 3 years with topical and systemic corticosteroids and systemic cyclosporin A for a bilateral anterior and posterior uveitis of unknown origin. The treatment did not result in resolution of the uveitis. A bilateral uveitic glaucoma developed and necessitated neodymium : YAG laser iridotomies and antiglaucoma medications. A systemic beta-blocker, metoprolol tartrate 50 mg b.i.d., was administered for palpitations because of idiopatic paroxysmal supraventricular tachycardia and short ventricular tachycardia. RESULTS: Following administration of metoprolol tartrate, the bilateral uveitis resolved. The corticosteroids and the cyclosporin A were withdrawn after 6 weeks without any recurrence. A trial to discontinue metoprolol after 6 months resulted in flare-up of the disease and only following its readministration the inflammation resolved. The patient is currently under metoprolol for a year without flare-ups. CONCLUSIONS: The use of metoprolol tartrate in this patient resulted in resolution of bilateral noninfectious uveitis. This is the first report of non-antiinfectious, antiinflammatory, or immunosuppressive drug effective for uveitis. It is possible that a subgroup of resistant uveitis may respond to drugs other than the traditional drugs, such as metoprolol, and that other forms of uveitis of unidentified origin exist.

Sneddon's syndrome: neuro-ophthalmologic manifestations in a possible autosomal recessive pattern.

Sneddon's syndrome is a rare neurodermatologic disorder that is manifested by multiple cerebrovascular accidents and livedo reticularis. The authors describe two siblings from one family with Sneddon's syndrome, suggesting autosomal recessive inheritance. The propositus presented with internuclear ophthalmoplegia and ophthalmic artery occlusion. These manifestations as well as the autosomal recessive inheritance have not yet been reported in Sneddon's syndrome.