ABSTRACT
BACKGROUND: Immune-mediated necrotizing myopathy (IMNM) is an idiopathic inflammatory myopathy (IIM). Though patients with IMNM were not considered to show skin rash, several reports have showed atypical skin conditions in patients with anti-3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR) antibody-positive IMNM (HMGCR-IMNM). The incidence and phenotype of skin conditions in patients with HMGCR-IMNM are not fully known. RESULTS: Among the 100 IIM patients diagnosed from April 2015 through August 2022, 34 (34%) presented some form of skin condition, with 27 having typical skin rashes; this included 13 patients with dermatomyositis (DM), 8 with anti-synthetase syndrome (ASS), and 6 with IMNM. Meanwhile, 8 of 19 patients with HMGCR-IMNM (42%) presented atypical skin lesions, but no patients with other IIMs did (p < 0.001). Skin eruption with ash-like scales was observed in four HMGCR-IMNM patients, and non-scaly red patches and lumps in the other four patients; accordingly, their skin manifestations were considered as other dermal diseases except for IIM. However, skin and muscle biopsies revealed the atypical skin conditions of patients with HMGCR-IMNM to have the same pathological background, formed by Bcl-2-positive lymphocyte infiltrations. CONCLUSIONS: HMGCR-IMNM patients frequently have atypical skin conditions of the neck and back. Skin biopsy specimens from these lesions showed the same Bcl-2-positive lymphocytic infiltrations as muscle biopsy specimens regardless of the different gross dermal findings. Thus, such atypical skin conditions may be suggestive for HMGCR-IMNM.
Subject(s)
Autoantibodies , Hydroxymethylglutaryl CoA Reductases , Myositis , Skin , Humans , Hydroxymethylglutaryl CoA Reductases/immunology , Female , Male , Middle Aged , Autoantibodies/immunology , Autoantibodies/blood , Adult , Skin/pathology , Skin/immunology , Myositis/immunology , Myositis/diagnosis , Aged , Skin Diseases/immunology , Skin Diseases/etiology , Muscular Diseases/immunology , Muscular Diseases/diagnosis , BiopsyABSTRACT
Under the assumption that neurovascular compression can be caused by elongation or kinking of the artery, we measured the length of each section of the vertebrobasilar artery, compared the lengths between various age groups, and evaluated the involvement of the arterial sections in brain stem compression in 1000 cases. The lengths of the posterior inferior cerebellar artery (PICA)-union of both vertebral arteries (union), union-anterior inferior cerebellar artery (AICA), AICA-superior cerebellar artery (SCA), and union- superior cerebellar artery were measured using an arterial length measuring tool applied to three-dimensional images. The presence of arterial compression of the brain stem was also evaluated. The mean age of the participants was 66.8 ± 12.9 years, and 44.8% were men. Intraclass correlation coefficients for both inter-rater reliability and intra-rater reliability were high in all sections. The vessel lengths of left AICA-SCA (P < 0.001), left union-SCA (P < 0.0001), left PICA-union (P = 0.03), right AICA-SCA (P = 0.002), right union-SCA (P < 0.0001), and right PICA-union (P = 0.04) increased with age, but each R2 was less than 0.05. Brain stem compression by PICA or vertebral artery was identified in 13.8% of cases. The proportion of the presence of brain stem compression was significantly higher in the cases with arterial elongation than in those without (P = 0.01). Vessel length increased with age, but age had a relatively small impact on the elongation of vertebrobasilar arteries. Brain stem compression might be caused by kinking of the artery rather than arterial elongation.
