The spinal fluid of a newborn is received in the laboratory….

The spinal fluid of a newborn is received in the laboratory. The mother had received limited prenatal care, works at a pet store and has been suffering from gastroenteritis for the past ten days. The Gram stain of the spinal fluid shows the presence of tiny Gram positive diphtheroid along with neutrophils. The specimen is plated onto sheep blood agar, chocolate agar and MacConkey agar. You would expect it to grow on: