CT imaging for prediction of complications and recurrence in acute uncomplicated diverticulitis

Acute diverticulitis: beyond the diagnosis: predictive role of CT in assessing risk of recurrence and clinical implications in non-operative management of acute diverticulitis

PURPOSE

The aim of the study is to identify CT findings that are predictive of recurrence of acute uncomplicated colonic diverticulitis, to better risk-stratify these patients for whom guidelines recommend a conservative outpatient treatment and to determine the appropriate management with an improvement of health costs.

MATERIALS AND METHODS

Over the past year, 33 patients enrolled in an outpatient integrated care pathway (PDTA) for uncomplicated acute diverticulitis with 1-year follow-up period, without recurrence, and 33 patients referred to Emergency Department for a recurrent acute diverticulitis were included. Images of admission CT were reviewed by two radiologists and the imaging features were analyzed and compared with Chi-square and Student t tests. Univariate and multivariate Cox regression models were employed to identify parameters that significantly predicted recurrence in 1-year follow-up period and establish cutoff and recurrence-free rates. The maximally selected rank statistics (MSRS) were used to identify the optimal wall thickening cutoff for the prediction of recurrence.

RESULTS

Patients with recurrence showed a greater mean parietal thickness compared to the group without recurrence (16 mm vs. 11.5 mm; HR 1.25, p < 0.001) and more evidence of grade 4 of peridiverticular inflammation (40% vs. 12%, p = 0.009, HR 3.44). 12-month recurrence-free rates progressively decrease with increasing thickness and inflammation. In multivariate analysis, only parietal thickness maintained its predictive power with an optimal cutpoint > 15 mm that causes a sixfold increased risk of recurrence (HR 6.22; 95% CI, 3.05-12.67; p < 0.001). Beyond thickness and peridiverticular inflammation, predictive value of early recurrence within 90 days from the 1st episode resulted also an Hinchey Ib on admission CT.

CONCLUSIONS

The maximum wall thickening and the grade of peridiverticular inflammation can be considered as predictive factors of recurrence and may be helpful in selecting patients for a tailored treatment to prevent the risk of recurrence.

The Indications for and Timing of Surgery for Diverticular Disease

BACKGROUND

Diverticular disease is one of the more common abdominal disorders. In 2016, approximately 130 000 patients received inpatient treatment for diverticular disease in Germany. The disease has a number of subtypes, each of which has an appropriate treatment. In this article, we present the current surgical indications and optimal timing of surgery for diverticular disease.

METHODS

This review is based on publications that were retrieved by an extensive, selective search in Medline and the Cochrane Library (1998-2018) for studies and guidelines with information on the indications for surgery in diverticular disease.

RESULTS

Studies of evidence grades 2 to 4 were available. Patients receiving a diagnosis of freely perforated diverticulitis and peritonitis (Classification of Diverticular Disease [CDD] type 2c) should be operated on at once. Covered perforated diverticulitis with a macroabscess (>1 cm, CDD type 2b) may be an indication for elective surgery after successful conservative treatment. New evidence from a randomized, controlled trial suggests that elective surgery should also be considered for patients with chronic recurrent diverticulitis (CDD type 3b). The decisive factor in such cases is the impairment of the quality of life for the individual patient. Elective surgery is indicated in chronic recurrent diverticulitis with complications (fistulae, stenoses). Asymptomatic diverticulosis (CDD type 0) and uncomplicated diverticulitis (CDD type 1) are not surgical indications. Likewise, in diverticular hemorrhage (CDD type 4), surgery is only indicated in exceptional cases, when conservative treatment fails.

CONCLUSION

The surgical indication and the proper timing of surgery depend on the type of disease that is present. Future studies should more thoroughly investigate the effect of surgery on the quality of life in patients with the various types of diverticular disease.

Diverticulitis: An Update From the Age Old Paradigm

For a disease process that affects so many, we continue to struggle to define optimal care for patients with diverticular disease. Part of this stems from the fact that diverticular disease requires different treatment strategies across the natural history- acute, chronic and recurrent.

To understand where we are currently, it is worth understanding how treatment of diverticular disease has evolved. Diverticular disease was rarely described in the literature prior to the 1900’s. In the late 1960’s and early 1970’s, Painter and Burkitt popularized the theory that diverticulosis is a disease of Western civilization based on the observation that diverticulosis was rare in rural Africa but common in economically developed countries. Previous surgical guidelines focused on early operative intervention to avoid potential complicated episodes of recurrent complicated diverticulitis (e.g., with free perforation) that might necessitate emergent surgery and stoma formation. More recent data has challenged prior concerns about decreasing effectiveness of medical management with repeat episodes and the notion that the natural history of diverticulitis is progressive. It has also permitted more accurate grading of the severity of disease and permitted less invasive management options to attempt conversion of urgent operations into the elective setting, or even avoid an operation altogether.

The role of diet in preventing diverticular disease has long been debated. A high fiber diet appears to decrease the likelihood of symptomatic diverticulitis. The myth of avoid eating nuts, corn, popcorn, and seeds to prevent episodes of diverticulitis has been debunked with modern data. Overall, the recommendations for “diverticulitis diets” mirror those made for overall healthy lifestyle – high fiber, with a focus on whole grains, fruits and vegetables.

Diverticulosis is one of the most common incidental findings on colonoscopy and the eighth most common outpatient diagnosis in the United States. Over 50% of people over the age of 60 and over 60% of people over age 80 have colonic diverticula. Of those with diverticulosis, the lifetime risk of developing diverticulitis is estimated at 10–25%, although more recent studies estimate a 5% rate of progression to diverticulitis. Diverticulitis accounts for an estimated 371,000 emergency department visits and 200,000 inpatient admissions per year with annual cost of 2.1–2.6 billion dollars per year in the United States. The estimated total medical expenditure (inpatient and outpatient) for diverticulosis and diverticulitis in 2015 was over 5.4 billion dollars. The incidence of diverticulitis is increasing.

Besides increasing age, other risk factors for diverticular disease include use of NSAIDS, aspirin, steroids, opioids, smoking and sedentary lifestyle. Diverticula most commonly occur along the mesenteric side of the antimesenteric taeniae resulting in parallel rows. These spots are thought to be relatively weak as this is the location where vasa recta penetrate the muscle to supply the mucosa. The exact mechanism that leads to diverticulitis from diverticulosis is not definitively known.

The most common presenting complaint is of left lower quadrant abdominal pain with symptoms of systemic unwellness including fever and malaise, however the presentation may vary widely. The gold standard cross-sectional imaging is multi-detector CT. It is minimally invasive and has sensitivity between 98% and specificity up to 99% for diagnosing acute diverticulitis. Uncomplicated acute diverticulitis may be safely managed as an out-patient in carefully selected patients. Hospitalization is usually necessary for patients with immunosuppression, intolerance to oral intake, signs of severe sepsis, lack of social support and increased comorbidities. The role of antibiotics has been questioned in a number of randomized controlled trials and it is likely that we will see more patients with uncomplicated disease treated with observation in the future

Acute diverticulitis can be further sub classified into complicated and uncomplicated presentations. Uncomplicated diverticulitis is characterized by inflammation limited to colonic wall and surrounding tissue. The management of uncomplicated diverticulitis is changing. Use of antibiotics has been questioned as it appears that antibiotic use can be avoided in select groups of patients. Surgical intervention appears to improve patient’s quality of life. The decision to proceed with surgery is recommended in an individualized manner.

Complicated diverticulitis is defined as diverticulitis associated with localized or generalized perforation, localized or distant abscess, fistula, stricture or obstruction. Abscesses can be treated with percutaneous drainage if the abscess is large enough. The optimal long-term strategy for patients who undergo successful non-operative management of their diverticular abscess remains controversial. There are clearly patients who would do well with an elective colectomy and a subset who could avoid an operation all together however, the challenge is appropriate risk-stratification and patient selection. Management of patients with perforation depends greatly on the presence of feculent or purulent peritonitis, the extent of contamination and hemodynamic status and associated comorbidities. Fistulas and strictures are almost always treated with segmental colectomy.

After an episode of acute diverticulitis, routine colonoscopy has been recommended by a number of societies to exclude the presence of colorectal cancer or presence of alternative diagnosis like ischemic colitis or inflammatory bowel disease for the clinical presentation. Endoscopic evaluation of the colon is normally delayed by about 6 weeks from the acute episode to reduce the risk associated with colonoscopy. Further study has questioned the need for endoscopic evaluation for every patient with acute diverticulitis. Colonoscopy should be routinely performed after complicated diverticulitis cases, when the clinical presentation is atypical or if there are any diagnostic ambiguity, or patient has other indications for colonoscopy like rectal bleeding or is above 50 years of age without recent colonoscopy.

For patients in whom elective colectomy is indicated, it is imperative to identify a wide range of modifiable patient co-morbidities. Every attempt should be made to improve a patient’s chance of successful surgery. This includes optimization of patient risk factors as well as tailoring the surgical approach and perioperative management. A positive outcome depends greatly on thoughtful attention to what makes a complicated patient “complicated”.

Operative management remains complex and depends on multiple factors including patient age, comorbidities, nutritional state, severity of disease, and surgeon preference and experience. Importantly, the status of surgery, elective versus urgent or emergent operation, is pivotal in decision-making, and treatment algorithms are divergent based on the acuteness of surgery. Resection of diseased bowel to healthy proximal colon and rectal margins remains a fundamental principle of treatment although the operative approach may vary.

For acute diverticulitis, a number of surgical approaches exist, including loop colostomy, sigmoidectomy with colostomy (Hartmann’s procedure) and sigmoidectomy with primary colorectal anastomosis. Overall, data suggest that primary anastomosis is preferable to a Hartman’s procedure in select patients with acute diverticulitis. Patients with hemodynamic instability, immunocompromised state, feculent peritonitis, severely edematous or ischemic bowel, or significant malnutrition are poor candidates. The decision to divert after colorectal anastomosis is at the discretion of the operating surgeon. Patient factors including severity of disease, tissue quality, and comorbidities should be considered. Technical considerations for elective cases include appropriate bowel preparation, the use of a laparoscopic approach, the decision to perform a primary anastomosis, and the selected use of ureteral stents.

Management of the patient with an end colostomy after a Hartmann’s procedure for acute diverticulitis can be a challenging clinical scenario. Between 20 – 50% of patients treated with sigmoid resection and an end colostomy after an initial severe bout of diverticulitis will never be reversed to their normal anatomy. The reasons for high rates of permanent colostomies are multifactorial. The debate on the best timing for a colostomy takedown continues. Six months is generally chosen as the safest time to proceed when adhesions may be at their softest allowing for a more favorable dissection. The surgical approach will be a personal decision by the operating surgeon based on his or her experience. Colostomy takedown operations are challenging surgeries. The surgeon should anticipate and appropriately plan for a long and difficult operation. The patient should undergo a full antibiotic bowel preparation. Preoperative planning is critical; review the initial operative note and defining the anatomy prior to reversal. When a complex abdominal wall closure is necessary, consider consultation with a hernia specialist. Open surgery is the preferred surgical approach for the majority of colostomy takedown operations. Finally, consider ureteral catheters, diverting loop ileostomy, and be prepared for all anastomotic options in advance.

Since its inception in the late 90’s, laparoscopic lavage has been recognized as a novel treatment modality in the management of complicated diverticulitis; specifically, Hinchey III (purulent) diverticulitis. Over the last decade, it has been the subject of several randomized controlled trials, retrospective studies, systematic reviews as well as cost-efficiency analyses. Despite being the subject of much debate and controversy, there is a clear role for laparoscopic lavage in the management of acute diverticulitis with the caveat that patient selection is key.

Segmental colitis associated with diverticulitis (SCAD) is an inflammatory condition affecting the colon in segments that are also affected by diverticulosis, namely, the sigmoid colon. While SCAD is considered a separate clinical entity, it is frequently confused with diverticulitis or inflammatory bowel disease (IBD). SCAD affects approximately 1.4% of the general population and 1.15 to 11.4% of those with diverticulosis and most commonly affects those in their 6th decade of life. The exact pathogenesis of SCAD is unknown, but proposed mechanisms include mucosal redundancy and prolapse occurring in diverticular segments, fecal stasis, and localized ischemia. Most case of SCAD resolve with a high-fiber diet and antibiotics, with salicylates reserved for more severe cases. Relapse is uncommon and immunosuppression with steroids is rarely needed. A relapsing clinical course may suggest a diagnosis of IBD and treatment as such should be initiated. Surgery is extremely uncommon and reserved for severe refractory disease.

While sigmoid colon involvement is considered the most common site of colonic diverticulitis in Western countries, diverticular disease can be problematic in other areas of the colon. In Asian countries, right-sided diverticulitis outnumbers the left. This difference seems to be secondary to dietary and genetic factors. Differential diagnosis might be difficult because of similarity with appendicitis. However accurate imaging studies allow a precise preoperative diagnosis and management planning. Transverse colonic diverticulitis is very rare accounting for less than 1% of colonic diverticulitis with a perforation rate that has been estimated to be even more rare. Rectal diverticula are mostly asymptomatic and diagnosed incidentally in the majority of patients and rarely require treatment. Giant colonic diverticula (GCD) is a rare presentation of diverticular disease of the colon and it is defined as an air-filled cystic diverticulum larger than 4 cm in diameter. The pathogenesis of GCD is not well defined.

Overall, the management of diverticular disease depends greatly on patient, disease and surgeon factors. Only by tailoring treatment to the patient in front of us can we achieve optimal outcomes.

ACR Appropriateness Criteria® Left Lower Quadrant Pain-Suspected Diverticulitis

This review summarizes the relevant literature regarding imaging of suspected diverticulitis as an etiology for left lower quadrant pain, and imaging of complications of acute diverticulitis. The most common cause of left lower quadrant pain in adults is acute sigmoid or descending colonic diverticulitis. Appropriate imaging triage for patients with suspected diverticulitis should address the differential diagnostic possibilities and what information is necessary to make a definitive management decision. Patients with diverticulitis may require surgery or interventional radiology procedures because of associated complications, including abscesses, fistulas, obstruction, or perforation. As a result, there has been a trend toward greater use of imaging to confirm the diagnosis of diverticulitis, evaluate the extent of disease, and detect complications before deciding on appropriate treatment. Additionally, in the era of bundled payments and minimizing health care costs, patients with acute diverticulitis are being managed on an outpatient basis and rapid diagnostic imaging at the time of initial symptoms helps to streamline and triage patients to the appropriate treatment pathway. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

European Society of Coloproctology: guidelines for the management of diverticular disease of the colon

AIM

The goal of this European Society of Coloproctology (ESCP) guideline project is to give an overview of the existing evidence on the management of diverticular disease, primarily as a guidance to surgeons.

METHODS

The guideline was developed during several working phases including three voting rounds and one consensus meeting. The two project leads (JKS and EA) appointed by the ESCP guideline committee together with one member of the guideline committee (WB) agreed on the methodology, decided on six themes for working groups (WGs) and drafted a list of research questions. Senior WG members, mostly colorectal surgeons within the ESCP, were invited based on publication records and geographical aspects. Other specialties were included in the WGs where relevant. In addition, one trainee or PhD fellow was invited in each WG. All six WGs revised the research questions if necessary, did a literature search, created evidence tables where feasible, and drafted supporting text to each research question and statement. The text and statement proposals from each WG were arranged as one document by the first and last authors before online voting by all authors in two rounds. For the second voting ESCP national representatives were also invited. More than 90% agreement was considered a consensus. The final phrasing of the statements with < 90% agreement was discussed in a consensus meeting at the ESCP annual meeting in Vienna in September 2019. Thereafter, the first and the last author drafted the final text of the guideline and circulated it for final approval and for a third and final online voting of rephrased statements.

RESULTS

This guideline contains 38 evidence based consensus statements on the management of diverticular disease.

CONCLUSION

This international, multidisciplinary guideline provides an up to date summary of the current knowledge of the management of diverticular disease as a guidance for clinicians and patients.

Acute diverticulitis: old challenge, current trends, open questions

Acute diverticulitis (AD) is an increasing issue for health systems worldwide. As accuracy of clinical symptoms and laboratory examinations is poor, a pivotal role in preoperative diagnosis and severity assessment is played by CT scan. Several new classifications trying to adapt the intraoperative Hinchey's classification to preoperative CT findings have been proposed, but none really entered clinical practice. Treatment of early AD is mostly conservative (antibiotics) and may be administered in outpatients in selected cases. Larger abscesses (exceeding 3 to 5 cm) need percutaneous drainage, while management of stages 3 (purulent peritonitis) and 4 (fecal peritonitis) is difficult to standardize, as various approaches are nowadays suggested. Three situations are identified: situation A, stage 3 in stable/healthy patients, where various options are available, including conservative management, lavage/drainage and primary resection/anastomosis w/without protective stoma; situation B, stage 3 in unstable and/or unhealthy patients, and stage 4 in stable/healthy patients, where stoma-protected primary resection/anastomosis or Hartmann procedure should be performed; situation C, stage 4 in unstable and/or unhealthy patients, where Hartmann procedure or damage control surgery (resection without any anastomosis/stoma) are suggested. Late, elective sigmoid resection is less and less performed, as a new trend towards a patient-tailored management is spreading.

Diagnostic accuracy of acute diverticulitis with unenhanced low-dose CT

Background

The aim of this study was to evaluate the diagnostic accuracy of unenhanced low‐dose CT (LDCT) in acute colonic diverticulitis in comparison with contrast‐enhanced standard‐dose CT (SDCT).

Methods

All patients with clinically suspected diverticulitis who underwent LDCT followed by SDCT between January and October 2017 were evaluated prospectively. CT examinations were assessed for signs of diverticulitis, complications and other differential diagnoses by three independent radiologists (two consultants and one fourth‐year resident) using SDCT as the reference method. Sensitivity and specificity were calculated and Cohen's κ coefficient was used for agreement analyses.

Results

Of the 149 patients included (mean age 66·7 years, M : F ratio 0·4), 107 (71·8 per cent) had imaging consistent with diverticulitis on standard CT. Sensitivity and specificity values for a diverticulitis diagnosis using LDCT were 95–99 and 86–100 per cent respectively, and respective values for identification of complications were 58–73 and 78–100 per cent. The corresponding κ values among the three readers for diagnosis were 0·984, 0·934 and 0·816, whereas κ values for complications were 0·680, 0·703 and 0·354. Of the 26 patients who presented with other causes of abdominal symptoms identified on standard CT, 23 were diagnosed correctly on LDCT. Missed cases included splenic infarction (1) and segmental colitis (2).

Conclusion

The diagnostic accuracy of LDCT was high for the presence of acute diverticulitis. However, as signs of complicated disease can be missed using the low‐dose protocol, use of LDCT as a primary examination method should not preclude SDCT when complications may be suspected.

Development and validation of a diagnostic prediction model distinguishing complicated from uncomplicated diverticulitis

OBJECTIVES

Most diverticulitis patients (80%) who are referred to secondary care have uncomplicated diverticulitis (UD) which is a self-limiting disease and can be treated at home. The aim of this study is to develop a diagnostic model that can safely rule out complicated diverticulitis (CD) based on clinical and laboratory parameters to reduce unnecessary referrals.

METHODS

A retrospective cross-sectional study was performed including all patients who presented at the emergency department with CT-proven diverticulitis. Patient characteristics, clinical signs and laboratory parameters were collected. CD was defined as > Hinchey 1A. Multivariable logistic regression analyses were used to quantify which (combination of) variables were independently related to the presence or absence of CD. A diagnostic prediction model was developed and validated to rule out CD.

RESULTS

A total of 943 patients were included of whom 172 (18%) had CD. The dataset was randomly split into a derivation and validation set. The derivation dataset contained 475 patients of whom 82 (18%) patients had CD. Age, vomiting, generalized abdominal pain, change in bowel habit, abdominal guarding, C-reactive protein and leucocytosis were univariably related to CD. The final validated diagnostic model included abdominal guarding, C-reactive protein and leucocytosis (AUC 0.79 (95% CI 0.73-0.84)). At a CD risk threshold of ≤7.5% this model had a negative predictive value of 96%.

CONCLUSION

This proposed prediction model can safely rule out complicated diverticulitis. Clinical practitioners could cautiously use this model to aid them in the decision whether or not to subject patients to further secondary care diagnostics or treatment.

Complicated Disease Course in Initially Computed Tomography-Proven Uncomplicated Acute Diverticulitis

Background: Although uncomplicated acute diverticulitis has a benign disease course, some patients are at increased risk for complications. Identification of these patients may aid the selection of treatment strategies such as outpatient treatment. This study aimed to assess the rate and timing of a complicated disease course in initially computed tomography (CT)-proven uncomplicated diverticulitis, and to identify risk factors for the development of these diverticular complications. Patients and Methods: Computed tomography-proven, left-sided uncomplicated diverticulitis patients from two cohorts were included. Main outcome measure was complicated diverticulitis (perforation, abscess, obstruction, or fistula) within three months after presentation. Risk factors for diverticular complications were identified using multivariable logistic regression. Results: Of the 1,087 patients with initially CT-proven uncomplicated diverticulitis, 4.9% (53/1,087) developed complicated diverticulitis. Most perforations and abscesses (16/21) occurred during the first 10 days, whereas colonic obstruction and fistula occurred during three months of follow-up. Independent risk factors for the transition from uncomplicated to complicated diverticulitis were American Society of Anesthesiologists (ASA) classification 3/4 (odds ratio [OR] 4.43, 95% confidence interval [CI] 1.57-12.48), duration of symptoms before presentation longer than five days (OR 3.25, 95% CI 1.72-6.13), vomiting (OR 3.94, 95% CI 1.96-7.92), and C-reactive protein (CRP) above 140 mg/L (OR 2.86, 95% CI 1.51-5.43). Conclusion: Approximately one in 20 patients with CT-proven uncomplicated diverticulitis develops a complicated disease course within three months; perforation and abscess occur predominantly within 10 days after presentation. Patients with systemic comorbidity, symptoms for more than five days, those who vomit, or have high CRP levels at presentation are at risk for diverticular complications after an uncomplicated initial presentation and may warrant closer observation.

Index C-reactive protein predicts increased severity in acute sigmoid diverticulitis

Purpose

Conservative management is successful in unperforated (Hinchey Ia) acute diverticulitis (AD) and also generally in local perforation or small abscesses (Hinchey Ib). A higher degree of radiological severity (Hinchey >Ib), ie, a larger abscess (>3-4 cm) or peritonitis, commonly requires percutaneous drainage or surgery. Retrospective studies show that high levels of C-reactive protein (CRP) distinguish Hinchey Ia from all cases of minor and major perforations (Hinchey >Ia). The current study aims to evaluate the usefulness of CRP in distinguishing AD with a higher degree of severity (Hinchey >Ib) from cases that can be treated noninvasively (Hinchey Ia/Ib).

Methods

Data from consecutive patients with AD were collected prospectively. All underwent computed tomography (CT). Index parameters obtained at the initial evaluation at the emergency unit were analyzed to assess the association with the outcome. The exclusion criteria comprised concomitant conditions that affected CRP baseline levels.

Results

Ninety-nine patients were analyzed. Eighty-eight had mild radiological grading (Hinchey Ia/Ib), and 11 had severe radiological grading (Hinchey >Ib) (median index CRP 80 mg/L vs 236 mg/L [P<0.001]). White blood cells, neutrophils/lymphocytes, serum creatinine, serum glucose, generalized peritonitis, generalized abdominal tenderness, urinary symptoms, and index CRP were related to severe disease. Index CRP was the only independent predictor for Hinchey >Ib (P=0.038). The optimal cutoff value calculated by receiver operating characteristic curve analysis was found to be 173 mg/L (sensitivity 90.9%, specificity 90.9%, P<0.001). All patients who underwent radiological drainage or surgery had an index CRP >173 mg/L and Hinchey >Ib.

Conclusion

CRP levels >173 mg/L obtained at the initial evaluation at the emergency unit predict major acute complications in AD. These patients commonly require urgent percutaneous drainage or surgical management.

Surgical management in acute diverticulitis and its association with multi-detector CT, modified Hinchey classification, and clinical parameters

PURPOSE

To assess whether CT findings, clinical parameters, and modified Hinchey classification are predictive of management outcomes of patients with acute diverticulitis.

MATERIALS AND METHODS

Data were accrued between January 2014 and December 2015. A total of 301 adult subjects were identified from radiology reports, of which six who did not met the inclusion criteria were excluded, thus yielding 295 subjects. Subjects were 43.1% (n = 127) male and 56.9% female (n = 168), with mean age 51.9 years (range 18-90). Two independent abdominal radiologists reviewed all scans; imaging features and a modified Hinchey classification were scored. Descriptive statistics compared the relationships between imaging findings, clinical parameters obtained from medical record review, and modified Hinchey classification with management outcomes.

RESULTS

CT findings associated with surgical management include the presence of a pericolonic fluid collection (36.8% vs. 8.2%, P = 0.0001), colonic fistula (13.2% vs. 0.4%, P = 0.0002), extraluminal air (26.4% vs. 9.3%, P = 0.0052), bowel obstruction (5.2% vs. 0.0%, P = 0.0162), and a modified Hinchey score of Ib or higher (55.3% vs. 11.7%, P = 0.0001). Slightly lower systolic blood pressure was also associated with operative management (137.2 mmHg vs. 128.2 mmHg, P = 0.0220).

CONCLUSION

Specific CT imaging features and modified Hinchey classification are associated with subsequent surgical management in patients with acute diverticulitis.

Emergency Presentations of Diverticulitis

Acute diverticulitis is a common condition that has been increasing in incidence in the United States. It is associated with increasing age, but the pathophysiology of acute diverticulitis is still being elucidated. It is now believed to have a significant contribution from inflammatory processes rather than being a strictly infectious process. There are still many questions to be answered regarding the optimal management of acute diverticulitis because recent studies have challenged traditional practices, such as the routine use of antibiotics, surgical technique, and dietary restrictions for prevention of recurrence.

Antibiotics versus no antibiotics in the treatment of acute uncomplicated diverticulitis - a systematic review and meta-analysis

BACKGROUND

Acute uncomplicated diverticulitis (AUD) is common and antibiotics are the cornerstone of traditional conservative management. This approach lacks clear evidence base and studies have recently suggested that avoidance of antibiotics is a safe and efficacious way to manage AUD. The aim of this systematic review is to determine the safety and efficacy of treating AUD without antibiotics.

METHODS

A systematic search of Embase, Cochrane library, MEDLINE, Science Citation Index Expanded, and ClinicalTrials. gov was performed. Studies comparing antibiotics versus no antibiotics in the treatment of AUD were included. Meta-analysis was performed using the random effects model with the primary outcome measure being diverticulitis-associated complications. Secondary outcomes were readmission rate, diverticulitis recurrence, mean hospital stay, requirement for surgery and requirement for percutaneous drainage.

RESULTS

Eight studies were included involving 2469 patients; 1626 in the non-antibiotic group (NAb) and 843 in the antibiotic group (Ab). There was a higher complication rate in the Ab group however this was not significant (1.9% versus 2.6%) with a combined risk ratio (RR) of 0.63 (95% CI, 0.25 to 1.57, p=0.32). There was a shorter mean length of hospital stay in the Nab group (standard mean difference of -1.18 (95% CI, -2.34 to -0.03 p= 0.04). There was no significant difference in readmission, recurrence and surgical intervention rate or requirement for percutaneous drainage.

CONCLUSION

Treatment of AUD without antibiotics may be feasible with outcomes that are comparable to antibiotic treatment and with potential benefits for patients and the NHS. Large scale randomised multicentre studies are needed. This article is protected by copyright. All rights reserved.

Conservative Treatment of Acute Colonic Diverticulitis

Purpose of Review

Since the treatment of acute diverticulitis has become more conservative over the last years, knowledge of conservative treatment strategies is increasingly important.

Recent Findings

Several treatment strategies that previously have been imposed as routine treatment are now obsolete. Uncomplicated diverticulitis patients can be treated without antibiotics, without bed rest, and without dietary restrictions; and a selected group of patients can be treated as outpatients. Also, patients with isolated pericolic extraluminal air can be treated conservatively as well. Whereas some patient subgroups have been suggested to suffer from a more virulent disease course or higher recurrence rates, current evidence does not support all traditional understandings. Patients on immunosuppression or non-steroidal anti-inflammatory drugs seem to have a higher risk of complicated diverticulitis, but young patients do not. Data on the risk of recurrent diverticulitis in young patients is conflicting but the risk seems comparable to elderly patients. Besides the traditional treatments, several new treatment strategies have emerged but have failed thus far. Mesalazine does not have any beneficial effect on preventing recurrent diverticulitis based on current literature. Rifaximin and probiotics have been studied insufficiently in acute diverticulitis patients to conclude on their efficacy.

Summary

This review provides an overview of recent developments in conservative treatment strategies of acute diverticulitis and discusses the latest evidence on patient subgroups that have been suggested to suffer from an aberrant disease course.

Predictive factors on CT imaging for progression of uncomplicated into complicated acute diverticulitis

PURPOSE

Since outpatient treatment and omitting antibiotics for uncomplicated acute colonic diverticulitis have been proven to be safe in the majority of patients, selection of patients that may not be suited for this treatment strategy becomes an important topic. The aim of this study is to identify computed tomography (CT) imaging predictors for a complicated disease course of initially uncomplicated acute diverticulitis.

METHODS

CT imaging from a randomized controlled trial (DIABOLO study) of an observational vs. antibiotic treatment strategy of first-episode uncomplicated acute diverticulitis patients was re-evaluated. For each patient that developed complicated diverticulitis within 90 days after randomization, two patients with an uncomplicated disease course were randomly selected. Two abdominal radiologists, blinded for outcomes, independently re-evaluated all CTs.

RESULTS

Of the 528 patients in the DIABOLO trial, 16 patients developed complications (abscess > 5 cm, perforation, bowel obstruction) within 90 days after randomization. In the group with a complicated course of initially uncomplicated diverticulitis, more patients with fluid collections (25 vs. 0%; p = 0.009) and a longer inflamed colon segment (86 ± 26 mm vs. 65 ± 21 mm; p = 0.007) were observed compared to an uncomplicated course of disease. Pericolic extraluminal air was no predictive factor.

CONCLUSION

Fluid collections and to a lesser extent the length of the inflamed colon segment may serve as predictive factors on initial CT for a complicated disease course in patients with uncomplicated acute colonic diverticulitis. These findings may aid in the selection of patients not suitable for outpatient treatment and treatment without antibiotics.

Acute colonic diverticulitis: modern understanding of pathomechanisms, risk factors, disease burden and severity

INTRODUCTION

Conservative, non-antibiotic and non-surgical management of acute diverticulitis is currently being investigated. To better inform clinical decisions, better understanding of disease mechanisms, disease burden and severity is needed.

METHODS

Literature search of risk factors, pathophysiology, epidemiology and disease burden/severity reported over the last decade.

RESULTS

Acute diverticulitis is a common disease and has a high disease burden. Incidence of hospital admissions is reported around 71 per 100,000 population, with reported increase in several subpopulations over the last decades. The incidence is likely to increase further with the aging populations. Risk factors for left-sided acute diverticulitis include dietary, anthropometric and lifestyle factors. Disease mechanisms are still poorly understood, but a distinction between inflammation and infection is emerging. The integrative and complex role of the gut microbiota has become an interesting factor for both understanding the disease as well as a potential target for intervention using probiotics. Mild, self-limiting events are increasingly reported from studies of successful non-antibiotic management in a considerable number of cases. Risk markers of progression to or presence of severe, complicated disease are needed for better disease stratification. Current risk stratification by clinical, imaging or endoscopic means is imperfect and needs validation. Long-term results from minimal-invasive and comparative surgical trials may better help inform clinicians and patients.

CONCLUSIONS

Over- and under-treatment as well as over- and under-diagnosis of severity is likely to continue in clinical practice due to lack of reliable, robust and universal severity and classification systems. Better understanding of pathophysiology is needed.

Management of Diverticular Disease in Scandinavia

Throughout the last century, the incidence of diverticular disease of the colon has increased tremendously in industrialized countries; nevertheless, the management of this condition is still controversial. Although several international guidelines for the management of diverticular disease are based on the same evidence, the recommendations differ greatly, emphasizing the lack of high-quality prospective studies. In Scandinavia, official guidelines for the management of diverticular disease exist only in Denmark. However, the treatment policies are quite similar in all Scandinavian countries. Computed tomography is the first choice for imaging of acute diverticulitis and its complications. Furthermore, the use of antibiotics in uncomplicated diverticulitis is nearly abandoned in Scandinavia, whereas several international guidelines still recommend their use. There is a broad consensus that abscesses secondary to acute diverticulitis can safely be managed with percutaneous drainage, which is in line with international recommendations. The surgical management of perforated diverticulitis with peritonitis is still as controversial in Scandinavia as elsewhere. Common surgical options are laparoscopic peritoneal lavage, primary resection with anastomosis, and primary resection with terminal colostomy (Hartmann's procedure). Elective sigmoid resection in patients with diverticular disease seems to be performed less frequently in Scandinavia than in other European countries; the right indications are a current matter of debate. Symptomatic uncomplicated diverticular disease in the absence of diverticulitis has not gained great attention in Scandinavia.

Acute colonic diverticulitis: an update on clinical classification and management with MDCT correlation

Currently, the most commonly used classification of acute colonic diverticulitis (ACD) is the modified Hinchey classification, which corresponds to a slightly more complex classification by comparison with the original description. This modified classification allows to categorize patients with ACD into four major categories (I, II, III, IV) and two additional subcategories (Ia and Ib), depending on the severity of the disease. Several studies have clearly demonstrated the impact of this classification for determining the best therapeutic approach and predicting perioperative complications for patients who need surgery. This review provides an update on the classification of ACD along with a special emphasis on the corresponding MDCT features of the different categories and subcategories. This modified Hinchey classification should be known by emergency physicians, radiologists, and surgeons in order to improve patient care and management because each category has a specific therapeutic approach.