What diseases affect tissues?

Numerous diseases affect tissues, ranging from inflammatory conditions and degenerative disorders to cancers and infections. Virtually every medical condition involves tissue-level changes, though some specifically target particular tissue types.

Epithelial tissue diseases include cancers (lung, skin, breast, colorectal carcinomas), inflammatory conditions (dermatitis, gastritis), and functional disorders (irritable bowel syndrome affecting intestinal epithelium). Connective tissue diseases encompass autoimmune conditions (lupus, rheumatoid arthritis, scleroderma), degenerative disorders (osteoarthritis, osteoporosis), genetic conditions (Ehlers-Danlos syndrome, Marfan syndrome), and cancers (sarcomas, leukemias, lymphomas). Muscle tissue diseases include muscular dystrophies (genetic conditions causing progressive muscle weakness), inflammatory myopathies (polymyositis, dermatomyositis), muscle tumors (rhabdomyosarcoma), and functional disorders (muscle cramps, spasticity). Nervous tissue diseases cover neurodegenerative conditions (Alzheimer's disease, Parkinson's disease, ALS), demyelinating diseases (multiple sclerosis), neuropathies (diabetic neuropathy), strokes, brain tumors, and neurodevelopmental disorders. Infections affect all tissue types—bacteria, viruses, fungi, and parasites can invade and damage tissues throughout the body. Systemic diseases like diabetes affect multiple tissue types simultaneously, damaging blood vessels, nerves, and connective tissues. Early detection improves outcomes for most tissue diseases. Warning signs include unusual lumps or growths, persistent pain or inflammation, unexplained weakness or numbness, changes in tissue appearance or texture, and functional impairments. Medical evaluation enables diagnosis through physical examination, laboratory tests, imaging, and biopsy, leading to appropriate treatment that may include medications, surgery, physical therapy, or lifestyle modifications.