Review question
We reviewed the evidence about the effectiveness and safety of different treatments for distal intestinal obstruction syndrome (DIOS) in children and adults with cystic fibrosis.
Background
Cystic fibrosis is a common, life-limiting, inherited disease. One of the main features of cystic fibrosis is the thick, sticky mucus produced by many organs including the lungs, pancreas and intestine. DIOS occurs when mucus in the intestine combines with faeces and builds up to produce a mass. This mass can partially or completely block the intestine and cause symptoms such as vomiting, severe abdominal pain and a swollen stomach (abdominal distension). Once a diagnosis of DIOS has been made, the goal of therapy is to relieve the complete or partial blockage and ultimately prevent the need for any surgical intervention.
Search date
The evidence is current to: 12 October 2021.
Trial characteristics
The review included one trial with 20 people with cystic fibrosis who were aged between 7.1 and 23.2 years of age (average 13.1 years old). The 12-month trial compared a high dose of pancreatic enzymes with a low dose of pancreatic enzymes for treating chronic DIOS.
Key results
The trial did not report on our primary outcomes (time until DIOS successfully treated and treatment failure rate), but addressed two of our secondary outcomes; episodes of acute DIOS and the harmful effects that might occur in participants (the presence of an abdominal mass and abdominal pain). There were no numerical data available for these results, but the authors reported that there was no difference between high-dose or low-dose pancreatic enzymes.
Certainty of the evidence
We found the overall certainty of the evidence to be very low. The trial itself was only published as an abstract from a conference which did not include numerical data and it was not published as a full report. This meant that we do not know many details about the trial. We thought that the overall risk of bias was unclear, as the trial authors did not describe how participants were put into the treatment groups, whether any participants dropped out or whether the planned outcomes were the same as the reported outcomes. The trial also had a very small number of participants and a limited age range, making it difficult to draw conclusions about the relevance of the treatment for all people with cystic fibrosis.
There is a clear lack of evidence for the treatment of DIOS in people with cystic fibrosis. The included abstract did not address our primary outcome measures and did not provide numerical data for the two secondary outcomes it did address. Therefore, we cannot justify the use of high-dose pancreatic enzymes for treating DIOS, nor can we comment on the efficacy and safety of other laxative agents. From our findings, it is clear that more randomised controlled trials need to be conducted in this area.
Cystic fibrosis is the most common life-limiting autosomal recessive genetic disorder in white populations. Distal intestinal obstruction syndrome (DIOS) is an important morbidity in cystic fibrosis. It is the result of the accumulation of viscid faecal material within the bowel which combines with thick, sticky mucus produced in the intestines of people with cystic fibrosis. The intestine may be completely blocked (complete DIOS) or only partially blocked (incomplete DIOS). Once a diagnosis of DIOS has been made, the goal of therapy is to relieve the acute complete or incomplete faecal obstruction and ultimately prevent the need for surgical intervention.
This review aimed to evaluate the effectiveness and safety of different treatment regimens for the treatment of DIOS (complete and incomplete) in children and adults with cystic fibrosis.
We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register comprising references identified from comprehensive electronic database searches and handsearches of relevant journals and abstract books of conference proceedings. Date of search: 09 September 2021.
We also searched online trial registries. Date of last search: 12 October 2021.
Randomised controlled trials, quasi-randomised controlled trials (including cross-over trials (to be judged on an individual basis)) comparing the use of laxative agents or surgery for treating DIOS in children, young people and adults with cystic fibrosis to each other, placebo or no intervention.
Two authors independently screened papers, extracted trial details and assessed for risk of bias. The authors assessed the quality of evidence using GRADE.
There was one trial with 20 participants (16 females) included in the review. The mean age of participants was 13.1 years. The trial was a double-blinded, randomised cross-over trial which had a duration of 12 months in total and compared high-dose and low-dose pancreatic enzyme therapy. As only the abstract of the trial was available, the overall risk of bias was judged to be unclear. The trial did not address either of our primary outcomes (time until resolution of DIOS and treatment failure rate), but reported episodes of acute DIOS, presence of abdominal mass and abdominal pain. There were no numerical data available for these outcomes, but the authors stated that there was no difference between treatment with high-dose or low-dose pancreatic enzymes. The overall certainty of the evidence was found to be very low.