Cervical and Fecal Cultures

This week in lab we performed GI and genital tract cultures. The cervical culture was plated onto SBA, Choc, and MTM. There were 2 colonies on SBA and choc, but only one on MTM. Because isolate 1 grew on MTM as pinpoint, small, translucent colonies Neisseria was suspected. The gram stain showed gram negative diplococci, oxidase positive, and a bacticard was pro positive confirming Neisseria gonorrhoeae. The other isolate was catalase positive and gram stained diptheroids and were identified as Corynebacterium.

On the feces culture, there was no growth on CVA while XLD, MAC, and SBA had 2 isolates. On XLD, the colonies were yellow (lactose positive), SLF on MAC, a large, white, mucoid beta hemolytic colonies on SBA. This was presumed to be E. coli ad normal flora. Isolate 2 had clear colonies on XLD and MAC, and large gray beat hemolytic mucoid colonies on SBA. Because there was no black seen in the center of the colonies, KIA was alk/a, LIA was purple/ yellow, and urea negative, Shigella was suspected. The serotyping identified it as Shigella flexneri. The case given with this specimen was a 4 year old who attended daycare who presented with vomiting, diarrhea, fever, lethargy, and irritability. His stool had bloody streaks and had numerous WBCs. Shigella is commonly acquired via the fecal oral route and is common in daycare settings.

The following link is a case history on Shigella flexneri. http://www.jpma.org.pk/PdfDownload/995.pdf