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A M Zalin

Publications and source records attributed to A M Zalin.

10 recordsLinked to original sources

Familial nephropathic non-neuropathic amyloidosis: clinical features, immunohistochemistry and chemistry.

Classification of familial amyloidosis by the chemical nature of the fibrillar protein has become possible. Most such amyloidogenic proteins so far recognized are variant transthyretins, but two kindreds with the same apolipoprotein AI modification have been reported. We describe the clinical features of another such family in whom petechial skin rash appeared to be a marker for the disease, which was non-neuropathic and of the Ostertag-type. Immunohistochemistry showed the protein to be apolipoprotein AI, but allele-specific DNA amplification indicated that it was not the Arg26 variant previously identified.

Amyloidosis

Disappearing hypercalcaemia.

Four women presented with symptomatic hypercalcaemia and raised concentrations of serum parathyroid hormone (PTH). In each case, serum calcium returned spontaneously to normal. In two patients serum PTH also fell to the normal range and biochemical relapse has not occurred despite prolonged follow-up. In the others, serum PTH remained elevated and subsequent symptomatic hypercalcaemia necessitated parathyroidectomy. In the first two cases, autoparathyroidectomy is the most likely explanation; the initial fall in serum calcium in the other two patients is unexplained. Large fluctuations in serum calcium may occur in some patients with hyperparathyroidism and prolonged and careful observation is required when this occurs.

Aged

Elevation of free thyroxine measurements in patients without thyrotoxicosis.

The recent development of single step analogue assay techniques to measure free thyroxine in serum has meant that this estimation has become widely used as a first line test of thyroid function. However these assays are subject to in-vitro interference in two ways: where there is a variant serum albumin in familial dysalbuminaemic hyperthyroxinaemia, or where there are circulating thyroid hormone binding antibodies. In both these situations a spuriously high result for free thyroxine is obtained. This may have serious implications for patient management and we describe 10 patients in whom the finding of a misleadingly high free thyroxine concentration led to confusion in diagnosis and, in eight of the 10, to inappropriate antithyroid treatment. Clinicians should be aware of these technical problems and where a result for the free thyroxine concentration seems inappropriate to the patient's clinical state then measurement of thyrotrophin (TSH) by a sensitive immunometric method should be performed. If the results remain confusing the presence of a variant serum albumin or thyroid hormone binding antibodies should be sought.

Adult