Discussion
The clinical presentations and severity of SBO depend on the level of the blockage. Nausea, vomiting, abdominal cramps and distention, and the decrease or absence of the passage of stool and flatus are the main clinical manifestations of SBO. The more proximally obstruction site is located, the more fastly symptoms ocur.8 For the prediction of an adhesive SBO, history of a previous abdominal surgery has a sensitivity and specificity of 85% and 78%, respectively.9 In the present study, two patients (2.7%) in Group 2 denied any medical history for a possible cause of adhesion including abdominal operation, peritonitis, endometriosis or acute diverticulitis. On radiological examination, the level of obstruction was the terminal ileum in these two patients, while other patients had different levels of blockage which was possibly the adhesion site.
Blood markers are specific in nor in the diagnosis of SBO neither in determining the severity of the disease. In a prospective study of Cosse et al.,10 procalcitonin with a value of above 0.57 ng/mL was found to be a potential predictor for small bowel ischemia with a sensitivity of 83%. Radiological methods including erect/lateral decubitus plain radiographs, ultrasound (US) and computed tomography (CT) are applicable to establish a diagnosis.8, 9 A plain radiograph is considered as the first step radiological study. It is a diagnostic tool in 50-60% of the patients, while inconclusive or misleading for others.1, 8, 11 The US is a reliable tool with 90% sensitivity in the diagnosis of SBO. The US can reveal the presence of > 2.5-cm dilated small bowel loops and decreased bowel peristalsis.1, 9 Diagnostic value of intravenous contrast-enhanced CT is superior to plain radiograph and US. In addition to this, CT enables to determine the severity and location of the obstruction, possible cause for obstruction, and also to detect potential complications such as bowel ischemia and perforation.1, 8 Oral contrast is considered not to be required in the diagnosis of SBO. On the other hand, oral contrast used during conservative management is associated with less requirement of laparotomy and shorter hospital stay.1, 12 As our daily practice, we performed an erect plain radiograph as the first step imaging for suspected cases. In the presence of air-fluid levels, an abdominal CT was used in most patients in adhesive SBO group to identify the level and severity of obstruction, and also eliminate other possible abdominal pathologies. Due to its having onset in the last 24 hours and the absence of description in the available literature, a routine CT was performed for all patients in the wild pear group to understand the mechanism of obstruction (partial/total) (paralytic/mechanic).
Conservative treatment is considered as the preferred treatment option for adhesive SBO in the absence of acute abdomen signs or if there is no evidence of intestinal ischemia or perforation. Approximately three out of four SBO patients can be managed conservatively.8The optimal duration of conservative treatment is still unclear. However, 72 hours is thought a critical cutoff to review the operative option since a failed conservative treatment exceeding 72 hours is correlated with increased risk of small bowel resection, longer hospital stay and higher morbidity.1, 13-15 Surgical intervention is mandatory in case of small bowel ischemia/perforation or failure of conservative treatment. Historically, laparotomic adhesiolysis has been the preferred approach for adhesive SBO.1, 2 Laparoscopic adhesiolysis had been described in recent decades, and it was associated with a reduced risk of morbidity and in-hospital mortality.15, 16 Recurrence of SBO occurs in 12% of conservatively treated patients within 1 year and 20% of them after 5 years. That risk is 8% within 1 year and 16% after 5 years after surgical treatment.17 In the adhesive SBO group, 6 (10.3%) patients underwent surgery. Interestingly, all patients in the wild pear group dramatically had clinical improvement on the first day of admission. Recurrence only occurred after conservative treatment in the adhesive SBO group. Recognition of excessive consumption of wild pear as a predisposing factor for SBO and increased patient conscious during hospital stay possibly played a role in preventing recurrence in the wild pear group.
Patients in the wild pear group were considered as adhesive SBO at admission due to their frequently having a history of previous abdominal operation. Management of treatment was planned similar to adhesive SBO. The mechanism of obstruction was not clear after excessive consumption of wild pear. We evaluated patients for possible causes of obstruction. 1) At first, phytobezoar seemed to be a possible cause of obstruction due to being food-related SBO and declaration of consuming pear seeds by a few patients. However, all patients had a partial SBO and CT revealed the absence of a phytobezoar in the level of obstruction. 2) Recognition of hyperactive bowel sounds at admission eliminated the possibility of paralytic obstruction. 3) Hypokalemia-related pseudo-obstruction was ruled out because serum potassium levels were within or above normal limits.
On the other hand, some other possible mechanisms we could not identify might be playing a role. Oleaster-leafed pear might be including an unidentified metabolite (or metabolites) which inhibiting gastrointestinal motility by using several pathways. Psyllium is a well-known diet fibre source and widely used against both constipation and diarrhea.18 Mehmood et al.18reported a possible mechanism of the antidiarrheal effect of psyllium husk. They thought blockage of Ca+2 channels and activation of nitric oxide/cyclic guanosine monophosphate pathways by undefined components might be inhibiting gastrointestinal motility.
Traditional medicine is still preferred especially in rural regions and countries with inadequate health service. Endemic trees and herbs constitute the majority of medicines. Although oleaster-leafed pear grows in a limited region including Anatolia and Balkans, 23 different wild pear species grow in different regions worldwide.6 Other wild pear species or fruits may have a similar impact on the gastrointestinal system. We could not find similar studies in the available literature. All previous studies and case reports have described phytobezoars. Food-related SBO maybe has been neglected or unreported entity.
There are some limitations of the present study. Firstly, this is a retrospective study conducted in a single-center. Additionally, the described wild pear type grows in a limited area in the world and these results may not be applicable to other pear species. Finally, the number of patients is inadequate to draw strong conclusions. On the other hand, the main strength of the present study is it’s being the first series describing food-induced SBO which obstruction mechanism is not phytobezoars.