Page 869 - Textbook of Pathology, 6th Edition

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Figure 28.25 Rheumatoid arthritis. The characteristic histologic features are villous hypertrophy of the synovium and marked mononuclear
inflammatory cell infiltrate in synovial membrane with formation of lymphoid follicles at places.

3. Ankylosing spondylitis or rheumatoid spondylitis is TUBERCULOUS ARTHRITIS
rheumatoid involvement of the spine, particularly sacroiliac Tuberculous infection of the joints results most commonly
joints, in young male patients. The condition has a strong from haematogenous dissemination of the organisms from CHAPTER 28
HLA-B27 association and may have associated inflammatory pulmonary or other focus of infection. Another route of
diseases such as inflammatory bowel disease, anterior uveitis infection is direct spread from tuberculous osteomyelitis close
and Reiter’s syndrome.
to the joint. Uncommon in the West, the disease is seen not
infrequently in developing countries more commonly in
SUPPURATIVE ARTHRITIS
children and also in adults.
Infectious or suppurative arthritis is invariably an acute
inflammatory involvement of the joint. Bacteria usually reach MORPHOLOGIC FEATURES. Tuberculous involvement
the joint space from the bloodstream but other routes of of the joints is usually monoarticular type but tends to be
infection by direct contamination of an open wound or more destructive than the suppurative arthritis. Most
lymphatic spread may also occur. Immunocompromised and commonly involved sites are the spine, hip joint and knees,
debilitated patients are increasingly susceptible to and less often other joints are affected. Tuberculosis of The Musculoskeletal System
suppurative arthritis. The common causative organisms are the spine is termed Pott’s disease or tuberculous spondylitis.
gonococci, meningococci, pneumococci, staphylococci, Grossly, the affected articular surface shows deposition
streptococci, H. influenzae and gram-negative bacilli. of grey-yellow exudate and occasionally tubercles are
Clinically, the patients present with manifestations of any present. The joint space may contain tiny grey-white loose
local infection such as redness, swelling, pain and joint bodies and excessive amount of fluid.
effusion. Constitutional symptoms such as fever, neutrophilic Histologically, the synovium is studded with solitary or
leucocytosis and raised ESR are generally associated. confluent caseating tubercles. The underlying articular
cartilage and bone may be involved by extension of
MORPHOLOGIC FEATURES. The haematogenous infec- tuberculous granulation tissue and cause necrosis (caries).
tious joint involvement is more often monoarticular rather
than polyarticular. The large joints of lower extremities
such as the knee, hip and ankle, shoulder and GOUT AND GOUTY ARTHRITIS
sternoclavicular joints are particularly favoured sites. The Gout is a disorder of purine metabolism manifested by the
process begins with hyperaemia, synovial swelling and following features, occurring singly or in combination:
infiltration by polymorphonuclear and mononuclear 1. Increased serum uric acid concentration (hyperuricaemia).
leucocytes alongwith development of effusion in the joint 2. Recurrent attacks of characteristic type of acute arthritis
space. There may be formation of inflammatory in which crystals of monosodium urate monohydrate may be
granulation tissue and onset of fibrous adhesions between demonstrable in the leucocytes present in the synovial fluid.
the opposing articular surfaces resulting in permanent 3. Aggregated deposits of monosodium urate monohydrate
ankylosis. (tophi) in and around the joints of the extremities.