Citrobacter is a genus of bacteria found in the intestine and the environment. Some members can cause opportunistic infections. A genus-level stool finding needs to be distinguished from a specific species causing illness in a normally sterile site.
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Why the genus name is not a diagnosis
Citrobacter includes species such as C. freundii and C. koseri. The clinical significance of a finding depends on the organism, the specimen and the person’s circumstances. Public-health descriptions include intestinal carriage as well as opportunistic infections; they do not make every stool finding an infection. [1]
What GI-MAP measures
The report contains a Citrobacter group target and a separate Citrobacter freundii target. Read both according to their own labels. A high group result does not identify every species or prove that the C. freundii line should also be high. [2]
What an autoimmune-associated category means
Placement in a report category does not establish autoimmune disease, identify its cause or predict future illness. A bacterial DNA count cannot diagnose rheumatoid arthritis, inflammatory bowel disease or another immune-mediated condition. Symptoms and established clinical assessments remain necessary.
A high result also cannot demonstrate a urinary infection or determine antibiotic susceptibility. Those questions require evidence from the appropriate site and method, not an assumption based on the genus name.
What helps with interpretation
Bring the full report, symptoms, recent antibiotics and any relevant immune-system conditions. Ask whether the finding changes a concrete care decision and whether confirmation would add useful information.
Common questions
Is Citrobacter the same as C. freundii?
C. freundii is one species within the genus. A genus-level result is broader.
Does a negative stool result exclude Citrobacter infection elsewhere?
No. It does not test every body site or replace assessment of a suspected infection.
Sources and review
Sources checked October 7, 2026. Manufacturer material describes the test; clinical guidance and research support the interpretation limits.
- Public Health Agency of Canada: Citrobacter
- Diagnostic Solutions Laboratory: GI-MAP interpretive guide (manufacturer specifications)
Medical review of this article is pending. For a correction or source question, contact GI MAP Test.