osteomyelitis

PO

Definition: Inflammation of bones, i.e. inflammation of bone tissue and bone marrow. The vast majority are of infectious origin (infectious osteomyelitis).

Osteomyelitis may be pyogenic, fungal, or tubercular. In the elderly, urinary tract infection and diabetes are associated factors, while in younger adults, immunodeficiency and intravenous drug abuse may be predisposing factors.

Histologically, neutrophils, lymphocytes, plasma cells, necrotic bone with reactive new bone formation, capillary proliferation, and fibrosis are often seen.

Microbiologic cultures and special stains (acid fast, Grocott’s methenamine silver, periodic acid Schiff) are necessary to identify the specific organisms.

A clinical history of overlying skin ulceration, concurrent infection, or positive blood or tissue cultures favors osteomyelitis.

A predominance of acute and chronic inflammatory cells over histiocytes is also most consistent with osteomyelitis.

Etiology

 hematogenous osteomyelitis

• neonatal osteomyelitis
• salmonella osteomyelitis (4091185)
• syphilitic osteomyelitis (osseous syphilitic gumma)

 direct inoculation of bacteria

Variants

 acute osteomyelitis
 chronic osteomyelitis
 granulomatous osteomyelitis
 chronic recurrent multifocal osteomyelitis

Localization

 pyogenic spondylitis

See also

 septic arthritis