Gout
MeSH definition: Hereditary metabolic disorder characterized by recurrent acute arthritis, hyperuricemia and deposition of sodium urate in and around the joints, sometimes with formation of uric acid calculi.

Arthritis, Rheumatoid
MeSH definition: A chronic systemic disease, primarily of the joints, marked by inflammatory changes in the synovial membranes and articular structures, widespread fibrinoid degeneration of the collagen fibers in mesenchymal tissues, and by atrophy and rarefaction of bony structures. Etiology is unknown, but autoimmune mechanisms have been implicated.

Sjogren's Syndrome
MeSH definition: Chronic inflammatory and autoimmune disease in which the salivary and lacrimal glands undergo progressive destruction by lymphocytes and plasma cells resulting in decreased production of saliva and tears. The primary form, often called sicca syndrome, involves both KERATOCONJUNCTIVITIS SICCA and XEROSTOMIA. The secondary form includes, in addition, the presence of a connective tissue disease, usually rheumatoid arthritis.

Anklyosking Spondolytis
MeSH definition: The form of rheumatoid arthritis affecting the spine. It occurs predominantly in young males and produces pain and stiffness because of inflammation of the sacroiliac, intervertebral, and costovertebral joints. Etiology is unknown.

Arthritis,Psoriatic
MeSH definition: Syndrome in which psoriasis is associated with arthritis, often involving inflammation in terminal interphalangeal joints. A rheumatoid factor is not usually present in the sera of affected individuals.

Arthritis, Infectious
MeSH definition: Arthritis caused by bacteria, rickettsiae, mycoplasmas, viruses, fungi, or parasites. Bacterial arthritis is frequently caused by Staphylococcus aureus, Streptococcus pneumoniae, Haemophilus influenzae, and Neisseria gonorrhoeae. Viral arthritis is less common than bacterial arthritis and may be a manifestation of such viral diseases as mumps, rubella, hepatitis, etc.

Rheumatoid Nodules
MeSH definition: Subcutaneous nodules seen in 20-30% of rheumatoid arthritis patients. They may arise anywhere on the body, but are most frequently found over the bony prominences. The nodules are characterized histologically by dense areas of fibrinoid necrosis with basophilic streaks and granules, surrounded by a palisade of cells, mainly fibroblasts and histiocytes.

Connective Tissue Disease
MeSH definition: A heterogeneous group of disorders, some hereditary, others acquired, characterized by abnormal structure or function of one or more of the elements of connective tissue, i.e., collagen, elastin, or the mucopolysaccharides.

Lupus Erythematosus, Cutaneous
MeSH definition: A form of lupus erythematosus in which the skin may be the only organ involved or in which skin involvement precedes the spread into other body systems. It has been classified into three forms - acute (= LUPUS ERYTHEMATOSUS, SYSTEMIC with skin lesions), sub acute, and chronic (= LUPUS ERYTHEMATOSUS, DISCOID).

Scleroderma, Systemic
MeSH definition: A chronic, progressive dermatosis characterized by boardlike hardening and immobility of the affected skin, with visceral involvement, especially of lungs, esophagus, kidneys, and heart. It may be accompanied by calcinosis, Raynaud's phenomenon, and telangiectasis (CREST syndrome). It includes acrosclerosis and sclerodactyly.

Osteoarthritis
Osteoarthritis Arthritis is a general term that describes inflammation in joints. Osteoarthritis, also called degenerative joint disease, is the most common type of arthritis. It is associated with a breakdown of cartilage in joints and commonly occurs in the hips, knees, and spine. Also, it often affects the finger joints, the joint at the base of the thumb, and the joint at the base of the big toe.

1. MeSH definitions are definitions in medical vocabulary and scientific terms assigned specifically to documents.
1a. MeSH definitions and noted images were provided by HONselect.
2. Definition and/or image is courtesy of medstudents.com.