Stomach in a parastomal hernia: a rare complication of stomas

Abstract

Parastomal hernia (PSH) is one of the most known complications to end colostomies. However, PSH containing the stomach is rare: not many case reports were found in literature search. This case is a 92-year-old woman who was brought in by ambulance to the accident and emergency department with vomiting, abdominal distension, palpable mass on the left side of her abdomen and with reduced stoma effluent. Her abdominal CT scan showed a PSH containing a partially incarcerated gastric hernia. Although there are only few similar cases of PSH containing the stomach reported in the literature, an almost similar pattern in presentation of this unique case can be deduced following a thorough comparison of cases in the literature, which can be quite helpful both academically and clinically: they are often advanced in age and are usually women with end colostomies.

Background

The presence of stomach in a parastomal hernial (PSH) sac is rare in surgical practice. It represents an uncommon differential in cases of gastric outlet obstruction. Surgeons should suspect this in elderly people with end colostomies.

Case presentation

A 92-year-old woman brought in by an ambulance on account of worsening parastomal mass of about 4 days duration with associated lower abdominal distension, vomiting of brownish liquid material, upper abdominal pain and reduced stoma output. There is a background history of rectal cancer about 9 years ago for which she had abdominoperineal excision of the rectum with a permanent colostomy fashioned. She is known to have gastric ulcer and hypertension for which she takes omeprazole and atenolol, respectively. There is also a history of dementia with a Do Not Attempt Cardio-Pulmonary Resuscitation (DNACPR) form in place, although she has got capacity. The patient resides in a nursing care home with restricted strenuous activity but ambulatory, carrying out light work. On examination, temperature was 37.3°C, pulse rate of 90 beats/min and blood pressure was 139/79 mm Hg. She generally looked frail and cachectic. Abdomen was moderately distended. In addition, there is a left-sided partially reducible PSH; stoma bag was containing scanty dark material. The hernia measures about 18×14 cm in its widest dimensions with some tenderness. The rest of the abdomen was generally soft, lax and non-tender.

Investigations

The patient subsequently had a CT abdomen and pelvis after intravenous contrast on a portal venous phase. There is evidence of dilated gastric shadow on the CT (figures 1 and 2). The stomach is shown to be partly incarcerated in the PSH with suspicion of obstruction at this level. This is evident given the distinct air fluid level in the distally incarcerated stomach segment in the sac outside the abdominal cavity (figure 3) and the double gas shadow showing the proximal stomach segment within the abdomen and the distal part within the hernia sac (figure 4). Haemoglobin is 104 g/L, White Cell Count (WCC) 8.03×10⁹/L, C-reactive protein (CRP) 1 mg/L and lactate was 1.5 mmol/L.

Figure 1.

A plain CT scan of the abdomen showing the gastric shadow in the left iliac fossa.

Figure 2.

A coronal CT image of the abdomen showing a distally distended segment of the stomach.

Figure 3.

An axial CT scan of the abdomen showing the stomach with an air fluid level as it is entering the hernia sac.

Figure 4.

A sagittal section of the CT scan showing two gastric air shadows: one in the abdominal cavity and the second in the hernia sac.

Differential diagnosis

Due to the presentation of a parastomal mass on a background of colostomy secondary to sigmoid cancer, a suspicion of a hernia was clear at the onset; however, this was thought to be containing the small bowel or the omentum but the stomach was not in the differential.

The working diagnosis was PSH with intestinal loops until CT images were available.

Treatment

Considering the age and frailty, conservative management was compared with mesh repair and risk versus benefit were weighed and the conclusion was to manage her conservatively with a nasogastric drainage (NG) tube. An NG tube was subsequently introduced which drained about 2 L of brownish liquid in the first 24 hours. This helped in the reduction of the hernia, and subsequently NG tube was removed 48 hours later following reduced volume of effluent and spontaneous reduction of the hernia.

Outcome and follow-up

Patient made an impressive recovery with conservative management only and was discharged after 7 days on admission. No follow-up was arranged.

Discussion

The rate of PSH varies depending on the study under review. According to Carne et al, PSH affects 1.8%–28.3% of end ileostomies and 0%–6.2% of loop ileostomies. Following colostomy formation, the rates are 4.0%–48.1% for end colostomy and 0%–30.8% for loop colostomy.¹ Contents of PSH sac may include omentum, small bowel and colon. Stomach may appear in the PSH sac very rarely.²

Previously, the stomach has been reported to herniate into the thoracic space secondary to trauma or surgery on the stomach or near the diaphragm with a few cases presenting with incarceration.³ Some cases also report complicated paraesophageal or hiatal hernias.⁴ Finally, a more common type of hernias are the congenital diaphragmatic defects (Bochdalek’s and Morgagni’s hernia) usually identified on neonatal ultrasound.⁵

It is difficult to outrightly draw conclusions given a small number of study population. However, PSH is commoner in the elderly with an average age of 76 years as well as people with colostomies for an average period of 10 years from time of formation of the colostomy. Operative mesh repair has been favoured as a treatment option. Even at that, surgeons should consider non-operative nasogastric decompression in emergency situation especially when the candidate is frail.⁶ According to Sohn et al, female gender is another factor contributing to the appearance of a PSH.⁷ Our patient is a typical example of such frail candidate who needs conservative management.

According to the European Hernia society, PSH classification is based on the para hernia defect size (small is ≤5 cm) and the presence of a concomitant incisional hernia (cIH). Four types were defined: type I, small PSH without cIH; type II, small PH with cIH; type III, large PH without cIH and type IV, large PH with cIH. In addition, the classification grid includes details about whether the hernia recurs after a previous PSH repair or whether it is a primary PSH.⁸

According to Devlin and Kingsnorth, PSH is classified into type I, interstitial hernia; type II, subcutaneous hernia; type III, intrastomal hernia and type IV, peristomal hernia (stoma prolapse). Rubin et al⁹ have a similar classification as Devlin and Kingsnorth based on intraoperative findings and would not be discussed further here.¹⁰ Using the CT radiograph, Moreno-Matias et al classified PSH into 0 (normal), I (hernial sac containing stoma loop), II (sac containing omentum) and III (sac containing a loop other than stoma).¹¹

By perusing through the literature, the factors affecting the development of PSH have generally been divided into two—patient factors and technical factors. Among the identified patient factors, obesity (using the body mass index), diabetes mellitus and emergency surgery showed significant statistical difference when compared with control.¹² Obesity, using waist circumference, was further demonstrated as an independent factor.¹³ Age greater than 60 years and peristomal complication at the time of creation of the stoma were demonstrated to contribute to PSH in another study.¹⁴ Among the technical factors identified, stoma type presented a predominant factor with incidences more in colostomies than ileostomies and end stomas more than in loop stomas.¹ Also, the size of the stoma was important as stoma sizes less than 25 mm showed no PSH complications in one study.¹⁵

PSH is mostly managed conservatively when symptoms are mild and presentation non-abrupt with proper safety netting about the complications of strangulation. Stoma care using stoma belt helps a lot to improve the situation for this select group of patients, and, in most cases, no further intervention is required.¹⁶ Surgical option is advocated in situations when conservative management fails. Also, persistent debilitating symptoms such as peristomal skin thinning and breakdown, chronic abdominal pain, recurrent bowel obstructions, psychological distress and back pain¹⁷ are important reasons to abandon conservative care. Another significant determining factor for surgery is the mode of presentation. Acute presentation with obstruction with or without incarceration needs emergency operation to prevent strangulation. Surgical repair can be either direct tissue repair, mesh repair or by stoma relocation. Mesh repair gives a lower rate of recurrence (0%–33.3%) than direct tissue repair (46%–100%) or stoma relocation (0%–76.2%).¹ Mesh placement options can be onlay (within the subcutaneous layer on the anterior rectus sheath or external oblique fascia), or sublay (in the preperitoneal plane or anterior to the posterior rectus sheath), or intraperitoneally using the Sugarbaker or keyhole techniques (laparoscopically or open). In this group, laparoscopic Sugarbaker is the best preferred in terms of postop outcome and recurrence rates.¹⁸ The sublay technique was not found to have fewer recurrence rate compared with the onlay technique.¹⁹ Mesh type can be prosthetic or biologic. A study did not show a difference in PSH recurrence between the two. However, biologic mesh is more expensive making prosthetic mesh the preferred alternative.²⁰ Prophylactic mesh placement at the time of stoma fashioning is gaining recognition among surgeons with one study showing significant reduction in PSH incidences compared with non-mesh primary stomas.²¹

Patient’s perspective.

I am happy with the treatment received and feel very much relieved that a non-operative option was able to relieve my symptoms and restore more quality of life to me.

Learning points.

• The stomach in a parastomal hernia (PSH) is uncommon but possible.

• Conservative management alone with a nasogastric drainage tube works in PSH and should be offered when frailty and fitness for surgery is an issue.

• Possible risk factors of PSH appear to be advancing age, female gender and patients with end colostomies.