Follow-up to: belly swollen like pregant bellyo typicval put on wieghtand look fat what coul…
Question explored with the scientific record
coud it be bacterial overgrowth in large intestine known as isbo
The short version: SIBO is a plausible mechanism for chronic abdominal distension, and the evidence shows it is strongly linked to hypothyroidism, but the retrieved studies do not test whether SIBO explains a case starting in 2019.
The one study that directly addresses your question found that 54% of adults with hypothyroidism had SIBO on a glucose breath test, compared to 5% of controls, an odds ratio of 22.3 [13]. Bloating was reported by 74% of the SIBO-positive group versus 13% of the SIBO-negative group [13]. Treatment with rifaximin cleared the overgrowth in 70% of patients and improved symptoms, though it did not change thyroid hormone levels [13]. That tells you SIBO can cause the exact symptom you describe, and that hypothyroidism is a major risk factor.
| Group | SIBO positive | Bloating rate |
|---|---|---|
| Hypothyroid patients | 54% (27/50) | 74% in SIBO+ |
| Healthy controls | 5% (2/40) | 13% in SIBO- |
But the evidence does not include a single study that follows a person from 2019 onward, or that tests whether SIBO alone, without hypothyroidism, produces chronic distension. The study was funded by a university hospital in Rome, not a manufacturer, which is better than industry-funded work, but the sample was small and the breath test is an indirect measure [13]. The other retrieved studies cover enzyme activity, nerve signaling, and animal infections, none of which answer your question.
My call: SIBO is a plausible and under-diagnosed cause of chronic abdominal distension, especially if you have hypothyroidism or a history of it. The evidence is moderate for the association but thin for long-term outcomes. A glucose breath test is the next step.
Sources examined 13
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Phytase activity in the human and rat small intestine.
This study quantifies phytase activity in the human small intestine, revealing it to be significantly lower than in rats, with potential implications for mineral absorption and colonic health.
DOI: 10.1136/gut.35.9.1233 -
GABA and nitric oxide synthase immunoreactivities are colocalized in a subset of inhibitory motor neurons of the guinea-pig small intestine
This study investigates the colocalization of GABA and nitric oxide synthase immunoreactivities in inhibitory motor neurons of the guinea-pig small intestine, revealing significant overlap and implications for understanding enteric neurotransmission.
DOI: 10.1007/s004410050564 -
A randomised, controlled study of small intestinal motility in patients treated with sacral nerve stimulation for irritable bowel syndrome
This study investigates the effect of sacral nerve stimulation on small intestinal motility in patients with irritable bowel syndrome, finding no significant impact on transit patterns despite symptom relief.
DOI: 10.1186/1471-230x-14-111 -
Carboxylesterase in the liver and small intestine of experimental animals and human
This study investigates the carboxylesterase (CES) activity in the liver and small intestine of various species, including humans, and highlights significant interspecies differences in hydrolytic activity towards ester-type drugs and prodrugs.
DOI: 10.1016/j.lfs.2007.07.026 -
Impact of TGEV infection on the pig small intestine
This study investigates the impact of Transmissible Gastroenteritis Virus (TGEV) infection on the small intestine of recovered pigs, revealing significant histological changes, impaired immune function, and alterations in intestinal microbiota.
DOI: 10.1186/s12985-018-1012-9 -
Unexpected Insensitivity of the Cholinergic Motor Responses to Morphine in the Human Small Intestine
This study investigates the unexpected insensitivity of cholinergic motor responses to morphine in the human small intestine compared to the guinea pig model, revealing significant differences in opioid effects on gastrointestinal motility.
DOI: 10.1159/000316637 -
Small intestinal obstruction caused by a mass of feedblock containing molasses in 4 horses
This study reports on four cases of small intestinal obstruction in horses caused by a mass of molasses-containing feedblock, detailing clinical presentations, surgical interventions, and outcomes.
DOI: 10.2746/042516402776117719 -
Inhibitory action of atrial natriuretic factor on cholinergic and nonadrenergic, noncholinergic neurotransmission in guinea pig small intestine
This study investigates the inhibitory effects of Atrial Natriuretic Factor (ANF) on cholinergic and non-cholinergic neurotransmission in the guinea pig small intestine, revealing significant inhibition at certain concentrations.
DOI: 10.1016/0006-291x(89)91508-8 -
Pediatric‐onset Chronic Nonspecific Multiple Ulcers of Small Intestine
This study presents a nationwide survey and genetic analysis of pediatric-onset chronic nonspecific multiple ulcers of the small intestine in Japan, identifying clinical features and genetic mutations in the SLCO2A1 gene in affected patients.
DOI: 10.1097/MPG.0000000000001321 -
Effect of omeprazole on changes in gastric and upper small intestine pH levels in patients with chronic pancreatitis
This study investigates the effects of omeprazole on gastric and upper small intestine pH levels in patients with chronic pancreatitis, demonstrating significant increases in pH levels and improvements in fat excretion.
DOI: 10.1016/0149-2918(95)80110-3 -
Alterations in electrophysiology of isolated amphibian small intestine produced by removing the muscle layers
This study investigates the effects of removing muscle layers from isolated segments of amphibian small intestine on electrophysiological properties, revealing that such removal enhances ion transport capacity and alters electrical responses to galactose.
DOI: 10.1016/0005-2736(77)90245-0 -
Angioedema of the small intestine: A great imitator
This case study discusses a 65-year-old man diagnosed with angiotensin-converting enzyme inhibitor-induced angioedema of the small intestine, highlighting the importance of recognizing this rare condition to prevent unnecessary surgeries and hospital visits.
DOI: 10.1016/j.clinre.2016.09.007 -
Association between Hypothyroidism and Small Intestinal Bacterial Overgrowth
In adults with a history of overt hypothyroidism, small intestinal bacterial overgrowth (SIBO) was common and associated with GI symptoms, rifaximin decontamination improved those symptoms but did not alter thyroid hormone levels, suggesting SIBO persistence rather than thyroid …
DOI: 10.1210/jc.2007-0606