Diagnostic performance of colour duplex ultrasonography along with temporal artery biopsy in suspicion of giant cell arteritis.

OBJECTIVES: Giant cell arteritis (GCA) is a vasculitis that occurs in older adults, affecting vessels of medium and large caliber. GCA diagnosis is a challenge for general practitioners and specialists. The aim of this study was to retrospectively analyse performances of temporal artery biopsy (TAB) and colour duplex ultrasonography (CDU) for GCA diagnosis. METHODS: All patients with suspicion of GCA and who underwent both TAB and CDU between April 2009 and March 2014 were included in the study. A positive CDU examination was defined by halos on both superficial temporal arteries. Patients were classified based on the physician final diagnosis. RESULTS: Among the 42 eligible patients, 12 had an alternative diagnosis and 30 were diagnosed with GCA. Sensitivities were 77% and 80% for TAB and CDU examinations, respectively. Specificities were 100% for both tests. Twenty-nine (96.7%) patients with GCA had their diagnosis confirmed either by CDU and/or by TAB. Time lengths between the first medical examination and results of TAB and CDU were 15 and 4.2 days (p<0.001), respectively. CONCLUSIONS: Our study suggests that in suspected GCA, CDU may be used as first line examination followed by TAB in case of CDU negative results. Such algorithm needs to be further assessed in a multicentre prospective study.

Comprehensive characterization of a novel intronic pseudo-exon inserted within an e14/a2 BCR-ABL rearrangement in a patient with chronic myeloid leukemia.

We identified a novel breakpoint cluster region-ABL rearrangement in a chronic myeloid leukemia (CML) patient. The e14/a2 (b3/a2) type BCR-ABL mRNA incorporated a 42-nucleotide intronic insertion of ABL intron Ib between BCR exon e14 and ABL exon a2. As we hypothesized that the rearrangement between BCR and ABL genes occurred near the inserted sequence and because of the relative small size of BCR intron 14, we determined the BCR-ABL breakpoint at the genomic DNA level. Using a PCR-based method, this analysis revealed that i) BCR intron 14 brought a potential lariat branch point and the polypyrimidine tract, ii) the BCR-ABL breakpoint created a chimeric acceptor site, and iii) the inserted sequence of ABL intron Ib carried at its 3' end a well-conserved donor splice site. Therefore, the inserted sequence was flanked by canonical consensus splice sites and recognized as a pseudo-exon (as shown by splice site prediction and exon finder software). Moreover, the insertion did not disrupt the reading frame between BCR and ABL and did not produce a premature stop codon. Instead, this novel BCR-ABL chimeric transcript encoded a functional oncoprotein with an in-frame insertion of 15 new amino acids.