[A case of ventriculo-atrial shunt infection diagnosed by blood culture and serial cerebrospinal fluid protein measurement].

Abstract

Ventriculo-atrial shunt infection (VASI) may lead to sepsis and/or nephritis, making early diagnosis critical. VASI is usually diagnosed by cerebrospinal fluid culture conducted after ventricular puncture or shunt removal, both of which are invasive. Non-invasive attempts at diagnosis, however, present a nonspecific clinical picture unless shunt dysfunction is present. A 57-year-old woman treated with ventriculo-atrial shunt 10 months earlier due to hydrocephalus following subarachnoid hemorrhage developed a fever but evidenced no infected organs in general examination although Staphylococcus epidermidis was isolated several times upon blood culture. Enhanced brain computed tomography (CT) showed neither abnormal findings nor changes in ventricular size and no shunt dysfunction was demonstrated clinically. In cerebrospinal fluid examination, the protein level was 137 mg/dL and cell count and bacteriological findings were normal. 10 days later, however, the cell count and bacteriological findings were normal but protein was 180 mg/dL. The cerebrospinal fluid protein increase indicated VASI, and the shunt was removed. The woman's fever was immediately alleviated and Staphylococcus epidermidis was detected in the cerebrospinal fluid culture of the specimen from the shunt tip and its periphery. Blood culture is useful for identifying bacterial etiology of VASI if neither cerebrospinal fluid cell count increases nor abnormal bacteriological findings are observed, provided that cerebrospinal fluid protein increase are observed in serial measurement.