Chemical epidural abscess: case report

Abstract

SUMMARY Spinal epidural abscess accompanies blood-borne infection, vertebral osteomyelitis, or an overlying cutaneous source of infection. This report documents the development of a noninfective epidural abscess where the inflammatory response was induced by the highly irritant contents (keratin and cholesterol) of an underlying epidermoid. This was associated with aseptic meningitis.Since the original clinical description by Albers in 1833 and the classical anatomical study by Dandy in 1926, a number of reports and reviews of spinal epidural abscess have appeared in the literature (Heusner, 1948;Dus, 1960;Gindi and Fairburn, 1969). Similarly, subdural epidermoid cysts complicated by spontaneous or surgically induced chemical meningitis have been described (Critchley and Ferguson, 1928;Olivecrona, 1932;Decker and Gross, 1967;Cantu and Wright, 1968). Congenital dermal sinuses which communicate with intraspinal dermoid or epidermoid cysts associated with recurrent meningitis are well-known clinical entities (List, 1941;Mount, 1949). It is the purpose of this brief communication to report a case in which an aseptic, chemically induced epidural abscess was caused by an underlying epidermoid cyst within the subarachnoid space, in the absence of a communicating sinus tract. CASE REPORTThe patient was a 5 year old Mexican-American girl who had previously been admitted to the hospital at ages 2j and 3 years because of febrile convulsions. Lumbar punctures were performed on both occasions. These were described as yielding normal cerebrospinal fluid.She was readmitted to the hospital on 13 February 1969 because of fever, questionable nuchal rigidity, irritability, limping, and pain in both knees. On admission to the hospital, nuchal rigidity was no longer present and neurological examination was reported as normal. Temperature was 39°C (103-4°F). White cell count was 15,800/cu. mm with a slight shift to the left. All other laboratory examinations were normal except for a lumbar puncture which revealed normal pressure and slightly turbid fluid containing 1,842 white cells/cu. mm of which 93 % were polymorphonuclear leucocytes and the rest lymphocytes.The protein content was 145 mg/100 ml. and the sugar 20 mg/100 ml. (concomitant blood sugar 100 mg/ 100 ml.). A smear of the sediment and cultures were negative. The patient was treated with parenteral ampicillin and the temperature declined after four days. The patient remained irritable and pain in both knees persisted. Lumbar puncture once again revealed slightly turbid fluid under normal pressure, containing 3,500 leucocytes/cu. mm of which 91 % were polymorphonuclear leucocytes and the remainder lymphocytes. Sugar was 32 mg/100 ml. and the protein content 150 mg/ 100 ml. Smear and cultures were negative. Blood cultures were also negative. An intermediate strength PPD tuberculin test was negative.Clinical improvement was apparent during the ensuing days. A subsequent lumbar puncture was traumatic. The fluid contained 14,700 red blood cells/cu. mm and 190 white cells/cu. mm...