RESUMO
We prepared RNA probes from cloned segments of human and murine enteroviruses (EVs) for in situ hybridization of skeletal muscle biopsies from patients with dermatomyositis (DM), polymyositis, other inflammatory myopathies, and noninflammatory muscle diseases, and from normal control subjects. A probe derived from Theiler's murine encephalomyelitis virus (TMEV) detected viral RNA within mononuclear cells of the interstitial connective tissue in 3 of 5 patients with adult-onset DM. None of these patients showed positive hybridization to probes derived from human EVs (poliovirus type 1 and Coxsackie virus B3) applied to subjacent sections of the same biopsies. The remaining 2 adult DM patients, 4 patients with childhood-onset DM, and 24 non-DM patients did not react with either TMEV or human enterovirus probes. Histochemical stains for esterase and immunoperoxidase stains for Mac-1 antigen in the 3 DM patients who reacted positively revealed positive cells in the same distribution as, but in far greater number than, those positive by in situ hybridization. Immunoperoxidase staining for HLA-DR antigens revealed positive cells in the same distribution and number as were seen with the TMEV probe. We conclude that an EV-like agent, more closely related to TMEV than to human EVs, may be associated with DM and that this agent is probably localized within muscle macrophages that express class II major histocompatibility complex antigens.
Assuntos
Dermatomiosite/microbiologia , Músculos/patologia , Infecções por Picornaviridae/complicações , Adulto , Biópsia , Criança , Dermatomiosite/patologia , Humanos , Hibridização de Ácido NucleicoRESUMO
We have studied four children (ages 6 to 17 years) with chronic cholestasis who developed a slowly progressive neuromuscular disease characterized by ataxia, dysmetria, areflexia, loss of vibratory sensation, and a variable ophthalmoplegia. Serum vitamin E concentration were low in all patients prior to treatment. Muscle histochemical studies in all four patients showed autofluorescent basophilic esterase and acid phosphatase-positive cytoplasmic inclusions and occasional necrotic fibers. These distinctive muscle changes are similar to those described in vitamin E-deficient animals. Intramuscular injections of alpha tocopherol were required in three patients to achieve normal serum vitamin E values. High-dose oral supplementation was effective in one patient. After normalization of serum vitamin E concentrations for six to 14 months, the neurologic disease has improved in all four patients.