Objectives To identify the ankyrin-B gene mutations that cause long QT syndrome (LQTS) and determine the prevalence of such mutations in Japanese patients with LQTS. Methods We conducted a search for ankyrin-B gene mutation in 78 unrelated patients with LQTS (28 males and 50 females, aged 2 to 89 years). With informed consent from all the subjects and/or their parents, genomic DNA was purified from the white blood cells of the patients and amplified using polymerase chain reaction (PCR). Single-strand conformational polymorphism (SSCP) analysis of the amplified DNA was performed to screen for mutations and aberrant SSCP products were isolated and sequenced by dye terminator cycle sequencing method using an automated fluorescent sequencer. PCR and restriction fragment length polymorphism (PCR-RFLP) analysis was carried out to further confirm the missense mutations by comparison with samples from 150 normal healthy individuals.Results We identified a T to A transition mutation at position 4 603 in exon 40, resulting in the substitution of arginine for a tryptophan at amino acid residue 1 535 (W1535R) in the regulatory domain of 220-kD ankyrin-B, which is a highly conserved domain shared by different species. Conclusions This novel missense mutation in the ankyrin-B gene may bea cause of type 4LQTS. Ankyrin-B gene mutation might not play the major role in LQTS in Japanese.

Objective: Histological verification of epithelioid cell granuloma is important in diagnosing sarcoidosis; tissue sampling is a worldwide requirement. In 2006, to reduce medical expenses and avoid invasive procedures, diagnostic criteria without histological verification were permitted by the Japanese government. In 2015, new diagnostic criteria, allowed clinical diagnoses based on only respiratory, ocular, and cardiac systems with at least a two-system involvement, increasing the need to sample tissue from clinically unevaluable organs in suspected sarcoidosis. This study aimed to compare the characteristics of patients who were diagnosed with sarcoidosis according to the 2006 and 2015 criteria.Materials and Methods: Using the 2015 version, we re-evaluated the characteristics of 264 patients with diagnosed or suspected sarcoidosis according to the 2006 criteria, at Jichi Medical University Hospital between 2004 and 2012 (clinical diagnosis, 84; histological diagnosis, 117; suspected sarcoidosis 63).Results: Thirty-nine patients were diagnosed with suspected sarcoidosis due to the absence of at least a two-system involvement; two patients had insufficient laboratory data suggestive of sarcoidosis. Six patients moved from suspected sarcoidosis to a histological diagnosis because of a greater leniency in the criteria for supportive findings. The 2015 diagnostic criteria excluded patients with organ involvement without a requirement for systemic steroids from the clinical diagnosis group. A case of schwannoma, erroneously placed in the clinical diagnosis group by the 2006 criteria, was reclassified according to the 2015 criteria.Conclusion: The 2015 version is preferable for clinically diagnosing sarcoidosis, even without histological specimens, and provides guidance for indications for systemic treatment.