Singh and Toskes suggested evaluating a patient for small bowel bacterial overgrowth (SBBO) if certain findings are present. The authors are from the University of Florida in Gainesville.
There are 2 main drivers for the evaluation:
(1) signs and symptoms suggestive of small bowel bacterial overgrowth, especially the unexplained onset of diarrhea, steartorrhea, weight loss, iron deficiency or vitamin B12 deficiency
(2) conditions associated with SBBO
Either driver may be the presenting factor, with the presence of the second a reason to evaluate the patient.
Conditions associated with bacterial overgrowth:
(1) hypochlorhydria or achlorhydria, including atrophic gastritits, vagotomy, gastrectomy and protein-pump inhibitors (PPI)
(2) resection of the ileocecal valve
(3) afferent blind loop with a Billroth II partial gastrectomy
(4) surgical blind loop (from end-to-side anastomosis)
(5) intestinal obstruction (stricture, tumor, inflammation, tuberculosis, radiation)
(6) small bowel diverticulosis (duodenal, jejunal)
(7) gastrocolic or jejunocolic fistula
(8) intestinal dysmotility associated with scleroderma
(9) diabetic autonomic neuropathy
(10) chronic intestinal pseudo-obstruction
(11) Crohn's disease
(12) chronic pancreatitis
(13) cirrhosis
(14) immunodeficiency syndrome, including CLL and hypogammaglobulinemia
(15) end-stage renal disease
(16) cystic fibrosis
(17) myotonic muscular dystrophy
NOTE: The list of conditions overlaps with the list of Shearman et al (above).
The patient may also present with a label of
(1) chronic fatigue syndrome
(2) irritable bowel syndrome
(3) fibromyalgia.
