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Observational Study
. 2018 Jun 19;9(6):162.
doi: 10.1038/s41424-018-0030-7.

Brain fogginess, gas and bloating: a link between SIBO, probiotics and metabolic acidosis

Satish S C Rao  1 , Abdul Rehman  2 , Siegfried Yu  2 , Nicole Martinez de Andino  2
Affiliations
Observational Study

Brain fogginess, gas and bloating: a link between SIBO, probiotics and metabolic acidosis

Satish S C Rao et al. Clin Transl Gastroenterol. .

Abstract

Background: D-lactic acidosis is characterized by brain fogginess (BF) and elevated D-lactate and occurs in short bowel syndrome. Whether it occurs in patients with an intact gut and unexplained gas and bloating is unknown. We aimed to determine if BF, gas and bloating is associated with D-lactic acidosis and small intestinal bacterial overgrowth (SIBO).

Methods: Patients with gas, bloating, BF, intact gut, and negative endoscopic and radiological tests, and those without BF were evaluated. SIBO was assessed with glucose breath test (GBT) and duodenal aspiration/culture. Metabolic assessments included urinary D-lactic acid and blood L-lactic acid, and ammonia levels. Bowel symptoms, and gastrointestinal transit were assessed.

Results: Thirty patients with BF and 8 without BF were evaluated. Abdominal bloating, pain, distension and gas were the most severe symptoms and their prevalence was similar between groups. In BF group, all consumed probiotics. SIBO was more prevalent in BF than non-BF group (68 vs. 28%, p = 0.05). D-lactic acidosis was more prevalent in BF compared to non-BF group (77 vs. 25%, p = 0.006). BF was reproduced in 20/30 (66%) patients. Gastrointestinal transit was slow in 10/30 (33%) patients with BF and 2/8 (25%) without. Other metabolic tests were unremarkable. After discontinuation of probiotics and a course of antibiotics, BF resolved and gastrointestinal symptoms improved significantly (p = 0.005) in 23/30 (77%).

Conclusions: We describe a syndrome of BF, gas and bloating, possibly related to probiotic use, SIBO, and D-lactic acidosis in a cohort without short bowel. Patients with BF exhibited higher prevalence of SIBO and D-lactic acidosis. Symptoms improved with antibiotics and stopping probiotics. Clinicians should recognize and treat this condition.

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Conflict of interest statement

Guarantor of article: Satish S.C. Rao, M.D., Ph.D., FRCP (LON).

Specific author contributions: Dr. SSCR provided the overall concept and framework for the manuscript including identifying the link between this syndrome and clinical cases and developing breath tests, duodenal aspiration and culture, developing the protocols for metabolic testing and co-wrote the manuscript and proofed and finalized the article. Dr. AR and Dr. SY researched and identified appropriate articles and participated in case evaluations, contacting and following up patients, writing, referencing and data analysis and preparation of the manuscript. Ms. NMdA screened and assessed patients, coordinated their tests and evaluated them at follow-up visits and co-wrote the manuscript.

Financial support: None.

Potential competing interests: Dr. Rao reports no conflict of interest in the context of this report but has served as a consultant for Forest Laboratories, Ironwood Pharmaceuticals, Takeda Pharmaceuticals, Salix Pharmaceuticals and Given Imaging. The remaining authors declare no competing interests.

Figures

Fig. 1
Fig. 1. Consort flow diagram describing enrollment and disposition of metabolic and breath test results.
SIBO small intestinal bacterial overgrowth
Fig. 2
Fig. 2
Flow diagram describing the correlation between duodenal aspirate/culture results in both groups
Fig. 3
Fig. 3
Improvement in gastrointestinal symptoms after treatment as assessed by Global VAS Score in patients with brain fogginess
See this image and copyright information in PMC

Comment in

References

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