A Rare Variant of the Ulnar Artery with Important Clinical Implications: a Case Report

BACKGROUND: Variations in the major arteries of the upper limb are estimated to be present in up to one fifth of people, and may have significant clinical implications. CASE PRESENTATION: During routine cadaveric dissection of a 69-year-old fresh female cadaver, a superficial brachioulnar artery with an aberrant path was found bilaterally. The superficial brachioulnar artery originated at midarm level from the brachial artery, pierced the brachial fascia immediately proximal to the elbow, crossed superficial to the muscles that originated from the medial epicondyle, and ran over the pronator teres muscle in a doubling of the antebrachial fascia. It then dipped into the forearm fascia, in the gap between the flexor carpi radialis and the palmaris longus. Subsequently, it ran deep to the palmaris longus muscle belly, and superficially to the flexor digitorum superficialis muscle, reaching the gap between the latter and the flexor carpi ulnaris muscle, where it assumed is usual position lateral to the ulnar nerve. CONCLUSION: As far as the authors could determine, this variant of the superficial brachioulnar artery has only been described twice before in the literature. The existence of such a variant is of particular clinical significance, as these arteries are more susceptible to trauma, and can be easily confused with superficial veins during medical and surgical procedures, potentially leading to iatrogenic distal limb ischemia.

IgG4-Related Hashimoto's Thyroiditis - A New Variant of a Well Known Disease

Hashimoto's thyroiditis (HT) has been characterized for many years as a well-defined clinicopathologic entity, but is now considered a heterogeneous disease. IgG4-related HT is a new subtype characterized by thyroid inflammation rich in IgG4-positive plasma cells and marked fibrosis. It may be part of the systemic IgG4-related disease. We report a case of a 56-year-old Portuguese man who presented with a one-month history of progressive neck swelling and dysphagia. Laboratory testing revealed increased inflammatory parameters, subclinical hypothyroidism and very high levels of thyroid autoantibodies. Cervical ultrasound (US) demonstrated an enlarged and heterogeneous thyroid gland and two hypoechoic nodules. US-guided fine needle aspiration cytology was consistent with lymphocytic thyroiditis. The patient was submitted to total thyroidectomy and microscopic examination identified typical findings of HT, marked fibrosis limited within the thyroid capsule and lymphoplasmacytic infiltration, with >50 IgG4-positive plasma cells per high-power field and an IgG4/IgG ratio of >40%. After surgery, serum IgG4 concentration was high-normal. Symptoms relief and reduction in laboratory inflammatory parameters were noticed. Thyroid function is controlled with levothyroxine. To our knowledge we report the first case of IgG4-related HT in a non-Asian patient. We also perform a review of the literature regarding IgG4-related disease and IgG4-related HT. Our case highlights this new variant of the well known HT, and helps physicians in recognizing its main clinical features, allowing for proper diagnosis and treatment.

Variant Rett Syndrome in a Girl with a Pericentric X-Chromosome Inversion Leading to Epigenetic Changes and Overexpression of the MECP2 Gene

Rett syndrome is a neurodevelopmental disorder caused by mutations in the MECP2 gene. We investigated the genetic basis of disease in a female patient with a Rett-like clinical. Karyotype analysis revealed a pericentric inversion in the X chromosome -46,X,inv(X)(p22.1q28), with breakpoints in the cytobands where the MECP2 and CDKL5 genes are located. FISH analysis revealed that the MECP2 gene is not dislocated by the inversion. However, and in spite of a balanced pattern of X inactivation, this patient displayed hypomethylation and an overexpression of the MECP2 gene at the mRNA level in the lymphocytes (mean fold change: 2.55±0.38) in comparison to a group of control individuals; the expression of the CDKL5 gene was similar to that of controls (mean fold change: 0.98±0.10). No gains or losses were detected in the breakpoint regions encompassing known or suspected transcription regulatory elements. We propose that the de-regulation of MECP2 expression in this patient may be due to alterations in long-range genomic interactions caused by the inversion and hypothesize that this type of epigenetic de-regulation of the MECP2 may be present in other RTT-like patients.