An epidural abscess refers to a collection of pus and infectious material located in the

epidural space In anatomy, the epidural space is the potential space between the dura mater and vertebrae (spine). The anatomy term "epidural space" has its origin in the Ancient Greek language; , "on, upon" + dura mater also known as "epidural cavity", "e ...

superficial to the

dura mater In neuroanatomy, dura mater is a thick membrane made of dense irregular connective tissue that surrounds the brain and spinal cord. It is the outermost of the three layers of membrane called the meninges that protect the central nervous system. ...

which surrounds the

central nervous system The central nervous system (CNS) is the part of the nervous system consisting primarily of the brain and spinal cord. The CNS is so named because the brain integrates the received information and coordinates and influences the activity of all par ...

. Due to its location adjacent to brain or spinal cord, epidural abscesses have the potential to cause weakness, pain, and paralysis.

Types

Spinal epidural abscess

A spinal epidural abscess (SEA) is a collection of pus or inflammatory granulation between the

and the

vertebral column The vertebral column, also known as the backbone or spine, is part of the axial skeleton. The vertebral column is the defining characteristic of a vertebrate in which the notochord (a flexible rod of uniform composition) found in all chordata, ...

. Currently the annual incidence rate of SEAs is estimated to be 2.5-3 per 10,000 hospital admissions. Incidence of SEA is on the rise, due to factors such as an aging population, increase in use of invasive spinal instrumentation, growing number of patients with risk factors such as diabetes and intravenous drug use. SEAs are more common in posterior than anterior areas, and the most common location is the

thoracolumbar The vertebral column, also known as the backbone or spine, is part of the axial skeleton. The vertebral column is the defining characteristic of a vertebrate in which the notochord (a flexible rod of uniform composition) found in all chordates ...

area, where

is larger and contains more fat tissue. SEAs are more common in males, and can occur in all ages, although highest prevalence is during the fifth and seventh decades of life. Combined treatment - emergency surgery and antibiotics is the preferred treatment for the spinal epidural abscess, removing existing pus (which is tested for microorganisms to select the most appropriate antibiotic) and removing pressure from the spinal cord and nerve roots. Antibiotic therapy should start after obtaining pus for microbiological investigation.

Cranial epidural abscess

A cranial epidural abscess involves pus and granulation tissue accumulation in between the dura mater and cranial bone. These typically arise (along with

osteomyelitis Osteomyelitis (OM) is an infection of bone. Symptoms may include pain in a specific bone with overlying redness, fever, and weakness. The long bones of the arms and legs are most commonly involved in children e.g. the femur and humerus, while the ...

of a cranial bone) from infections of the ear or paranasal sinuses. They rarely can be caused by distant infection or an infected cerebral venous sinus thrombosis. ''

Staphylococcus aureus ''Staphylococcus aureus'' is a Gram-positive spherically shaped bacterium, a member of the Bacillota, and is a usual member of the microbiota of the body, frequently found in the upper respiratory tract and on the skin. It is often positive ...

'' is the most common pathogen. Symptoms include pain at the forehead or ear, pus draining from the ear or sinuses, tenderness overlying the infectious site, fever, neck stiffness, and in rare cases focal seizures. Treatment requires a combination of antibiotics and surgical removal of infected bone.

References

{{Spinal cord lesions Bacterial diseases General surgery