A rapid method for negative staining of fecal samples for diagnosis of viral-induced gastroenteritis by Transmission Electron Microscopy

Abstract

The most common etiologic agents for viral gastroenteritis are rotavirus, adenovirus, and members of the “small round structure virus” category (enterovirus, norwalk virus, calicivirus, astrovirus). A rapid diagnosis of viral infection can avoid unnecessary antibiotic therapy, extensive and costly medical workups and reduce the patient’s hospital stay. Pseudoreplication has been the preparation method of choice at many institutions, because of its concentrating effect on viral particles. Unfortunately, in addition to concentrating viral particles, this method also concentrates fecal debris, making the screening process quite difficult at times and time consuming.A rapid method of negative staining for viral particle identification in fecal samples is presented. The method first described by Cubitt et al has been modified, resulting in a reduction in the amount of debris and improved staining quality of the viral particles, while still concentrating the number of viral particles. This method requires less than 1 ml of stool specimen and may be prepared in less than three minutes.