Q: Several patients presented to my clinic with severe rosacea and marked corneal opacity. I know of reports of gastrointestinal-associated bacterial overgrowth. Is there sufficient evidence that eradicating this overgrowth helps with the corneal response?


A: “The question of treating gastrointestinal-associated bacterial overgrowth to improve ocular rosacea is an interesting one,” says Andrea Murphy, OD, and Richard Frick, OD, of the White River Junction VAMC in Vermont, who manage patients with severe ocular rosacea leading to corneal ulcer formation. “In short, small intestinal bacterial overgrowth (SIBO) is defined as an unexpected microbial concentration (>10^5 colony-forming units/mL) in the jejunal aspirate culture, and is caused by numerous predisposing disorders, including the reduction of gastric acid secretion, intestinal motor and anatomic abnormalities, and immune function impairment.”1

Though the amount of literature connecting rosacea and SIBO is limited, research suggests that patients with rosacea are 13 times more likely to have SIBO compared with healthy controls, they add.2 

Other gastrointestinal diseases associated with rosacea formation include Helicobacter pylori gastritis, ulcerative colitis, Crohn’s disease, inflammatory bowel disease and hypochlorhydria, says Sara Weidmayer, OD, of the VA Ann Arbor Healthcare System. “The propoposed mechanism of these GI diseases ultimately leading to rosacea is increased intestinal permeability, which transmits pro-inflammatory cytokines and bacterial products into the blood, leading to inflammation elsewhere in the body. Rosacea—a chronic inflammatory condition—is a manifestation of that inflammation,” she says. Regarding the ocular subtype of rosacea, she notes that a study does exist that links it with H. pylori, but adds that the study was small with no controls. 

Typical eyelid findings with ocular rosacea. Photo: Sara Weidmayer, OD

“There is a rapidly growing interest in examining the relationship of the human microbiome, particularly the portion that resides in the gut, and immune system development and activity,” says Johnathan Greene, MD, a corneal, cataract and refractive surgery specialist at the University of Michigan’s Kellogg Eye Center. “It is not a stretch to consider that rosacea, a disease characterized by inflammation, may be similarly affected by microbes residing in the gut.”

Regardless, consider coordinating with the patient’s primary care doctor if traditional topical or oral therapies for ocular rosacea fail, Drs. Murphy and Frick suggest. Diagnosis methods for SIBO other than the jejunal aspirate culture include lactulose and glucose H2/CH4 breath tests.1 Additionally, use of rifaximin may be beneficial.1-3 They also note that patients with a Demodex infestation and SIBO exhibited more severe rosacea, so a slit lamp evaluation to look for these mites may be warranted.2 Many of these patients are on long-term doxycycline or minocycline, and reports suggest chronic use of these drugs instigating a breach in immunologic tolerance to certain autoimmune syndromes.4 

1. Parodi A, Paolino S, Greco A, et al. Small intestinal bacterial overgrowth in rosacea: clinical effectiveness of its eradication. Clin Gastroenterol Hepatol. 2008 Jul:6(7):759-64.

2. Agnoletti AF, DE Col E, Parodi A, et al. Etiopathogenesis of rosacea: a prospective study with a three-year follow-up. G Ital Dermatol Venereol. 2006 Feb 18. [Epub ahead of print.]

3. Micromedix Solutions [online database]. Available at: www.micromedexsolutions.com/home/dispatch.

4. Lawson TM, Bulgen NA, Williams BD. Minocycline-induced lupus: clinical features and response to rechallenge. Rheumatology. 2001;40(3):329-35.