Rubin's 27: Skeletal Muscle Flashcards
What is the diagnosis? Heliotropic rash on the upper eyelids, face and trunk; Increased serum levels of creatinine kinase; Thought to be of autoimmune origin
Dermatomyositits
Surgical removal of what organ may be curative for many myasthenia gravis patients?
Thymus Many have thymoma that contributes to their illness.
What is the diagnosis? Direct muscle cell damage due to cytotoxic T cells; Association with anti-Jo1 antibody; Interstitial lung disease; Raynaud’s phenomenon; Nonerosive arthritis
Polymyositis
When dermatomyositis is seen in middle-aged men, it is often associated with what other disease?
Increased risk for epithelial cancer, most commonly of the lung
What is the diagnosis? Paraneoplastic disorder (usually associated with small cell carcinoma of the lung; Muscle weakness/wasting/fatigability; Responds to corticosteroid treatment;
Lambert Eaton Myasthenic Syndrome aka myasthenic myopathic syndrome
What is the disease? Pathogenic auto-IgG antibodies recognize voltage sensitive calcium channels that are expressed in both the motor nerve terminals and the cells of the associated cancer. These calcium channels are necessary for the release of ACh, thus their destruction is associated with weakness.
Lambert Eaton Myasthenic Syndrome aka myasthenic myopathic syndrome
What is the most common adult muscular dystrophy?
Myotonic dystrophy Autosomal dominant Slowing of muscle relaxation and wasting; Involves many muscle systems including the heart
What is the diagnosis? Atrophy of type I muscle fibers; Hypertrophy of type II muscle fibers
Myotonic dystrophy
What is the diagnosis? Inability to metabolize long-chain fatty acids due to an inability to transport these FAs to into the mitochondria (where they undergo beta-oxidation)
Carnitine Palmityl Transferase Deficiency
What is the diagnosis? Muscle pain after prolonged exercise; Possible myoglobinuria (dark color)
Carnitine Palmityl Transferase Deficiency
What is the diagnosis? Infant or neonatal presentation; Autosomal recessive; Severe hypotonia and areflexia; Enlarged tongue; Cardiomegaly; Often, death by cardiac failure within the first 2 years of life
Pompe Disease, a glycogen storage disease Inability to degrade glycogen Pompe is the most severe form Serum CK slightly to moderately increased
What is the diagnosis? Single muscle fiber necrosis and regeneration; Lymphocytic inflitration of muscle fibers;
Inclusion Body Myositis Inclusions are stained with Congo red and represent an intracellular amyloid
What is a possible complication of malignant hyperthermia after administration of an anesthetic such as halothane?
Rhabdomylysis
