A 58-Year-Old Woman with Acute Torsion of the Small Bowel Due to Diffuse Intestinal Lipomatosis

Introduction

Abnormal deposition of fat in the intestine is morphologically classified into isolated lipomas, multiple confined lipomas, diffuse nodular lipomas, and diffuse submucosal fat infiltration [1]. The deposition and spread of adipose tissue are typically limited to the submucosal layer [2]. Lipomatosis refers to the diffuse infiltration of mature fatty tissue into the submucosal layer without forming a tumor, which could also manifest as numerous lipomas. There is no gender bias in small intestinal lipomatosis. Both males and females are equally affected, as per the reports available to date [3]. It usually occurs after the age of 40 years [4]. The previous literature reports varying numbers of the first 3 types of abnormal fat deposition in the intestine. Small bowel lipomatosis is an exceedingly rare form of small bowel lipoma. Small bowel lipomatosis is broadly classified into segmental and diffuse types; the former is prevalent and presents an infiltrative growth of mature adi-pose tissue confined to 1 segment of the bowel [5]. The latter is rare [6], with fewer than 10 reported cases. This case report illustrates the rare diffuse type of small bowel lipomatosis.

Symptoms can become severe and require immediate medical intervention when small intestinal lipomatosis coexists with intussusception, bleeding, obstruction, or bowel perforation [7–10]. In this paper, we present a case of intestinal torsion and subsequent intestinal obstruction in a 58-year-old female patient, which is rare and attributed to diffuse submucosal infiltration of slight intestinal fat hyperplasia.

Case Report

A 58-year-old female patient presented to our Emergency Department with symptoms of intermittent lower abdominal cramps, abdominal distension, nausea, vomiting, and reduced ability to defecate, which had persisted for 2 days and worsened over the past half day. Despite her typical good health, she reported loss of appetite, concentration difficulties, and sleep disturbances since the onset of the condition.

During the physical examination after admission, the patient demonstrated a distended abdomen with taut abdominal muscles, widespread tenderness on palpation throughout the abdomen, absence of any palpable mass, hyperactive bowel sounds at 8 to 10 beats per min, audible splashing sounds, and no vascular bruits. Laboratory test results revealed a white blood cell count of 9.7×109/L and a hemoglobin level of 132 g/L. Urine tests, liver and kidney function indicators, and other routine tests were within the reference range.

The following day, a contrast-enhanced abdominal computed tomography (CT) scan was performed. It showed diffuse thickening of the small intestinal wall, with areas of hypodensity, fatty density, lumen narrowing, and wall thinning (Figure 1). The small intestine demonstrated a whirlpool-like distribution in the lower right abdomen, with localized thickening of the small intestinal wall and a fluid density shadow surrounding these areas (Figure 2). The proximal segment of the small intestine was observed to be dilated, air-filled, and fluid-filled. Minimal information could be obtained about the colon. CT angiography imaging revealed the presence of the mesenteric artery. However, no noticeable filling defect shadow was observed in the central stem lumen.

Considering the severity of the clinical symptoms, the imaging findings suggested acute intestinal torsion [11], extensive diffuse infiltrative lipomatosis of the small bowel, and the presence of intestinal wall and mesenteric edema. Consequently, an hour later, an urgent laparoscopic partial resection of the small bowel was performed. During the procedure, approximately 200 cm of the small bowel was found to be thickened, dilated, and twisted. Upon correction of the twisted intestinal collaterals, further examination revealed a large, soft-textured mass within the dilated intestinal lumen. A complete resection of the problematic intestinal segment, measuring 125 cm, was completed. The remaining small bowel was anastomosed endto-end, as a portion of the bowel showed no signs of ischemia. The resected specimen was sent for pathological examination (Figure 3). The submucosa of the small intestine revealed numerous soft, grayish-yellow nodules, accompanied by localized gray-red hemorrhagic areas and neutrophilic exudate.

Three days later, the pathology results showed that the lesion locally extended to the lamina propria. Previous literature on small intestinal lipomatosis showed that the lesion mostly involved the submucosa, and the lamina propria cases were rare. This case presented a thin mucosal layer of the intestinal wall, submucosal expansion, hyperplasia of fatty tissue, mixed lymphocytes, and small blood vessels (Figure 4). On postoperative day 6, the patient had no abdominal pain or distention, no symptoms of nausea or vomiting, and a return to normal defecation, and the surgical incision healed successfully, with no signs of pain, redness, or leakage. Her bowel sounds were noted to be regular at 4 per min. After 3 months, her gastrointestinal function was confirmed to have returned to normal during a follow-up appointment.

Discussion

The incidence of intestinal lipomas ranges from 0.035% to 4.4% [12] and can occur throughout the gastrointestinal tract, with the small intestine accounting for 25% of cases [13]. Lipomatosis of the small intestine is an extremely rare subtype of small intestinal lipoma whose etiology is unknown. Genetic disorders may result in multiple lipomas [14]. However, previous literature has only reported a single case of small intestinal lipomatosis in which the mother had a history of isolated cutaneous lipomas [15]. Therefore, the development of small intestinal lipomatosis is unlikely to be caused by genetic factors and may be linked to individual factors, such as abnormal fat metabolism and inflammatory stimuli. The literature reports the presence of mesenteric fat deposits in small intestinal lipomatosis cases with an average body mass index [16], indicating that localized disorders of fat metabolism, rather than generalized obesity, can be associated with the condition. Possible causes include mutations in the oncogene gene of phosphate and tension homology deleted on chromosome ten (PTEN), leading to PTEN missense tumor syndrome [17]. However, our patient did not have any family history of lipomatosis and had never received genetic counseling. Genetic testing was not conducted during this patient’s hospitalization, due to the urgent need for treatment.

Most patients with small intestinal lipomas can be asymptomatic or only mildly symptomatic. Zarrin-Khameh et al [18] suggest that their patient had a long course of the disease, was admitted to the hospital with chronic abdominal pain and occasional abdominal distension, and received a diagnosis of lipomatous polyposis after colonoscopy revealed multiple polyps in the esophagus, stomach, colon, and rectum. The pathology report showed diffuse thickening of the submucosal layer of the polyps and a marked increase in the submucosal layer of fat. Still, there were no signs of acute intestinal obstruction. Common symptoms include abdominal pain, occasional nausea and vomiting, black stool, diarrhea, constipation, and weight loss [19], which becomes apparent as the tumor enlarges [20]. The patient of Kumar et al [10] had been ill for 5 days with severe vomiting symptoms, and CT showed ileal lipoma leading to slight bowel torsion, compared with our case (the present case) in which diffuse infiltrative small bowel lipomatosis involved the jejunum ileum more extensively and was surrounded by exudates, and more emphasis was placed on analyzing the CT manifestations. Previous reports in the literature on clinical symptoms in patients with diffuse infiltrative small bowel lipomatosis are scarce, but Cojocari et al [9] report that the patient came to the clinic with 12 h of abdominal pain, nausea, vomiting, and absence of bowel symptoms and that intestinal lipomatosis had already been diagnosed in the past. The patient had multiple lipomas in the intestines and mesentery, presented with small bowel infarcts, and had a habit of frequent bowel movements postoperatively, which were special features, and no slight bowel torsion occurred.

After reviewing the past medical history and follow-up observations of the patient in this case, we concluded that the clinical diagnosis of acute intestinal obstruction was made after 2 days of illness, with typical symptoms of abdominal pain, nausea, vomiting, and cessation of defecation. Complications such as intussusception [21], intestinal perforation [4], and intestinal torsion [22] are common in cases of small bowel lipomatosis. Prior studies have given little attention to the etiology of complications arising from small intestinal lipomatosis. We hypothesize that the mesenteric torsion, in the present case, could have been due to an accumulation of diffusely infiltrating fatty tissue in the submucosa of the small intestine, leading to an abnormal weight distribution and altered peristaltic function [4] of the small intestine, causing it to twist around its axis and induce local ischemia. These manifestations, including abdominal distention, paroxysmal lower abdominal colic, nausea, vomiting, and reduced anal stoma evacuation, can be aggravated by torsion and can present imaging evidence of inflammatory changes, such as edema and exudation. Previous studies suggest that small bowel lipomatosis can extrinsically compress blood vessels, potentially leading to intestinal infarction and chronic mesenteric ischemia, which, if left untreated, can progress to acute mesenteric ischemia [4]. In the present case, the patient showed superficial vascularization of the distal mesentery on CT angiography. Still, there were no symptoms or signs of acute mesenteric ischemia, nor was the potential progression to acute mesenteric ischemia considered.

Abdominal CT scanning is the most reliable diagnostic tool for detecting small bowel lipomatosis, offering superior sensitivity and specificity to other imaging modalities, endoscopy, and standard endoscopic biopsies [23]. Typical CT images of isolated lipomas display well-demarcated masses, with fat attenuation and densities between −80 and −120 Hounsfield units [24]. The main characteristic of small intestinal lipomatosis is a homogenous, diffuse intramural region of hypodensity. While lipomas are present as asymmetrical masses, small bowel lipomatosis appears as a widespread adipose tissue infiltration into the submucosa [25,26]. The fatty infiltration in small intestinal lipomatosis is ill-defined and unencapsulated, allowing for easy differentiation between the 2 conditions. In the present case, the patient exhibited diffuse intestinal hypodensity, necessitating imaging analysis to differentiate between acute mesenteric ischemia [27,28] and strangulated intestinal obstruction [29].

For patients with long-term symptoms, capsule endoscopy or balloon-assisted small bowel enteroscopy can be used [13]. The benefits of endoscopy include real-time visualization, tissue biopsy collection, precise lesion localization, and the potential for interventional treatment [30]. In the present case, balloon-assisted small bowel enteroscopy was not conducted, owing to the severity of the patient’s intestinal torsion, which resulted in an immediate intestinal obstruction necessitating prompt partial small bowel resection. Surgical resection is the definitive treatment in severe or complicated cases [31,32], and there have been some cases of endoscopic resection [33]. The nature of the surgical procedure depends on the patient’s condition and the size, number, and location of the tumors. To prevent short bowel syndrome, it is critical to preserve at least 180 cm of the small intestine during surgical resection [34]. Patients with minor symptoms can undergo close follow-ups. According to the literature, some patients have reported symptom reduction 3 months after dietary modification.

In the present case, the symptoms of acute intestinal obstruction were typical, the course of the disease was short, and the examination was followed by a prompt CT scan, which showed significant thickening of the bowel, multiple fat densities within it, and signs of slight bowel torsion with peripheral exudation, and the symptoms were severe enough to warrant surgery as soon as possible. When faced with acute intestinal obstruction, it is essential to think that the etiology may be intestinal torsion due to solid lipoma.

Conclusions

This case report highlights a 58-year-old woman who experienced acute intestinal torsion due to diffuse submucosal infiltrative small bowel lipomatosis and highlights diagnostic imaging and histopathologic findings. Her rare CT presentation of diffuse thickening of the bowel with multiple internal fat densities and signs of intestinal torsion made it easy to mis-diagnose and miss the diagnosis. After surgery, the pathologic findings were small bowel lipomatosis. In patients with complications of small bowel lipomatosis, as in this case, the treatment of choice is resection of the affected bowel segment, depending on the severity of the disease.