Laboratory Collections and Sample Processing

Abstract

Skull, central nervous system and spine may be infected by various microorganisms which vary according to age of onset, pathogenesis, anatomic location, and underlying medical status. Laboratory collections, transport of specimens and sample processing are crucial for the isolation, identification, and characterization of causative pathogens. Pus, fluids, infected tissue, bone and debrided materials should be sent for routine microbiological and histopathological studies including aerobic and anaerobic bacteria, mycobacteria and fungal culture as well as antimicrobial sensitivity testing. Bacteria and fungi have characteristic appearance on a variety of culture medium and the final identification is based on biochemical tests. It is also important to recognize that many cranial or spinal infections are polymicrobial and culture-negative cases are not insignificant. Molecular studies might be useful to detect organisms that are difficult or slow to grow by culture. The results of antimicrobial susceptibility testing should be combined with clinical and neuroimaging information, experience, and local epidemiological data when selecting the most appropriate anti-infectious drugs for the patient. Histopathology is also useful for recognizing some specific infections like mycobacteria, fungi and parasites, and to rule out presence of a compounding tumoral, granulomatous, or atypical inflammatory process.