Inflammatory MyopathiesDisease Poly Myositis Dermatomyositis Inclusion Body MyositisTissue involved Inf. Of Skeletal Muscle Inf. Of Skeletal Muscle Inf. Of Skeletal Muscle Fibre Fibre & Skin FibreAge Adults Children & Adults Adults>50 yearsClinical Presentations Bilateral Proximal Bilateral Proximal Asymmetrical Distal Muscle Weakness Muscle Weakness. Muscle Weakness Skin Rash of Upper Eyelid Periorbital edemaMicroscopic Features Endomysial lymphocytic Perimysial and vascular Cytoplasmic Vacuoles Infiltration( CD 8) lymocytic infiltration and basophilic granules and amyloid. Skeletal muscle fibre Perifasciular Fibre regeneration and Atrophy EM: Filamentous degeneration Inclusions Skeletal muscle fibre regeneration and degenerationCancer Risk: Increased Risk Of : Lung , Stomach & Ovarian Cancers.
Myasthenic Syndromes. Disease Myasthenia Gravis Eaton-Lambert Gullian- Barre Syndrome SyndromeMechanism Autoantibodies against Autoantibodies against Antibodies against Ach. Receptors in NMJ Ca. Ion Channels in NMJ Schwann cells leading to Peripheral Nerve Demyelination & inflammationAssociated Diseases Thymoma or Thymic Small Cell Lung Cancer Preceded by Viral hyperplasia illnessGender Females > MalesClinical Presentation Muscular weakness of Proximal Muscle Muscle weakness Body but predominantly Weakness with an ascending affecting: paralysis. Facial Muscles Extraoccular Muscles with Loss of Deep Ptosis tendon reflexes May Involve Respiratory May Involve Muscles and cause Death Respiratory Muscles & cause deathAlleviating Factors Weakness worsens with Weakness improves with repeated contractions. repeated contractionsDiagnosis Nerve Conduction Studies.
Muscular Dystrophy Disease Duchene Muscular dystrophy Becker Muscular DystrophyIncidence Most Common & Severe Form of Less Common & Mild Form of Muscular dystrophy Muscular dystrophyGenetics X-linked Recessive X-linked RecessiveMutations Mutations lead to Absence of Mutations lead to Alteration of Dystropin protein Dystropin proteinClinical Presentations Rapidly Progressive Muscular Slowly Progressive Muscular Weakness weakness. Proximal weakness of Shoulder Muscle weakness of Pelvis and and pelvic Girdle Legs Calf Pseudohypertrophy Heart Failure and arrhythmia Heart involvement is rare. Respiratory insufficiency and infections Age 5- Onset of symptoms Later onset with variable progression and may lead a Age 10- Wheel chaired normal life span Age 20- Respiratory Failure and deathMicroscopic Features. Fibrosis and Fatty infiltration and Necrosis Skeletal muscle degeneration Skeletal muscle degeneration and regeneration and regenerationDiagnosis Muscle Biopsy Muscle Biopsy DNA Analysis DNA Analysis
Benign Soft Tissue tumors Tumors Type of cells Locations Lipoma Adipose tissue Trunk ( Most Common) Neck Proximal Extremities Dermatofibroma Dermal Spindle cell Extremities (Forms a red nodule that can be squeezed) Fibromatosis Fibrous tissue Infiltrates Muscle tissue Rhabdomyoma Striated Muscle cells Heart Tongue Vagina Leiomyoma Smooth muscle cells Uterus Stomach Malignant Soft Tissue Cancers Cancers Type of cells Locations Liposarcoma Adipose tissue Thigh ( Most Common) & lipoblasts Retroperitoneum Fibrosarcoma Thigh Upper LimbMalignant Fibrous Pleomorphic cells Thigh Histocytoma Retroperitoneum Embryonal Striated muscle cells Male – Mass seen protrudingRhabdomyosarcoma form penis Female- Mass seen protruding from Vagina Leiomyosarcoma Smooth Muscle cells Uterus GITNeurofibrosarcoma Nerve cells Peripheral Nervous system Synovial Sarcoma Glands and spindle cells Around Joints