Endocrine Abstracts

Gastrointestinal abnormalities in acromegaly include dolichomegacolon and increased prevalence of colonic polyps. No data are available on the small intestine. The aims of this study were to investigate orocecal transit time (OCTT) and the presence of small intestinal bacterial overgrowth (SIBO) in acromegaly. 41 acromegalic patients and 30 controls entered the study. Acromegalics were classified according to whether they were on medical treatment with somatostatin analogs (SSA): “treated” and “untreated” and according to clinical control: “controlled”, “uncontrolled” and “partially controlled”. Acromegalics and controls were submitted to a 10 g lactulose hydrogen (H₂) breath test (LH-BT) in order to determine the OCTT and presence of SIBO.

There is an increased prevalence of SIBO in acromegalics comparing to controls (P=0.000). OCTT was significantly slower in acromegalics comparing to controls (P=0.000).

Nine treated and 9 untreated acromegalics were positive for SIBO, without a statistical significant difference. Six controlled, 9 partially controlled and 3 uncontrolled acromegalics were positive for SIBO, without a statistical significant difference.There was a significantly lower OCTT in treated compared with untreated patients (P=0.02) and between these two groups and controls (P=0.00). There was no statistically significant difference for OCTT between controlled and uncontrolled acromegalics.

These data demonstrate for the first time that SIBO occurs more frequently in acromegalics than in controls, and medical therapy with SSA does not influence the presence of SIBO. OCTT is significantly delayed in acromegalics both in treated and in untreated ones and this suggests that acromegaly determines per se impairment of intestinal motility. Clinical control does not influence the OCTT, suggesting that this may be an irreversible complication. The slower OCTT may represent a risk factor for the development of SIBO. These alterations might be related to the occurrence of an autonomic intestinal disorder, as we have previously demonstrated for cardiac autonomic activity in acromegaly.