Significance of acquired diverticular disease of the vermiform appendix: a marker of regional neoplasms?

The Significance of Appendiceal Diverticulosis to the Emergency General Surgeon: A Case Report and Literature Review

Acute appendicitis is a common acute general surgical presentation; however, variants in the appendicular anatomy and the presence of cancers can complicate the surgical management of this condition. Appendiceal diverticula (AD) are rare pathological outpouchings along the appendix body. These outpouchings complicate and obscure the surgical planes, making adequate surgical resection of the appendix difficult. We report here the surgical management of a rare case of AD with a benign neuroma that highlights the importance of adequate pre-operative planning and variations in the standard anatomy. Through the literature review, the association of AD with cancers arising from the appendix is also presented.

Diverticulitis and Diverticulosis of the Appendix: A Case Series

Introduction Diverticula of the appendix is a rare entity, may be complicated by inflammation/infection, and clinically mimics acute appendicitis. The reported associated risk factors include male gender, Hirschprung's disease, cystic fibrosis and adult age, where some reports claim that they are also associated with an increased risk of appendiceal malignancy. Imaging has a place in pre-operative diagnosis, however, most of the cases were diagnosed during a pathological examination after surgery. They are associated with a higher rate of perforation (more than four times compared with classical acute appendicitis). In this review, we present a case series of five patients diagnosed with diverticulitis and one with diverticulosis of the appendix that were managed at a single centre. Our aim is to explore the common clinical, radiological, and intra-operative findings associated with this disease as well as the outcome of management. Materials and methods A total number of six cases of diverticular disease of the appendix diagnosed and managed at Basildon University hospital in the period between 2016 and 2020 were studied. The demographic details and clinical data including presenting symptoms, laboratory results, radiological characteristics, intraoperative findings and histopathological features were analysed. Results The study group included four males and two females, with an age range of 20-84 years. The most common presenting clinical symptoms were right iliac fossa abdominal pain, nausea, anorexia, and diarrhoea. Half of the cases showed a thickened appendix in the pre-operative CT scan. An inflamed or perforated appendix was seen in five cases as well as inflammation of the diverticula. Conclusion Appendiceal diverticulitis is an uncommon pathology that imitates acute appendicitis, and appendicectomy is the standard treatment. Prophylactic appendicectomy is recommended for non-inflamed diverticula - this is due to the potential risk of inflammation, perforation, and the risk of developing an appendiceal neoplasm.

Complicated appendicular diverticulitis

Appendiceal diverticulitis, a frequently underdiagnosed entity, differs from typical appendicitis by the presence of an inflamed appendiceal diverticulum. Appendiceal diverticulitis is a surgical emergency which has an increased risk of perforation compared to typical appendicitis. We will discuss a surgically and pathologically confirmed case of complicated appendiceal diverticulitis and its management implications.

A Case of a Rare, Incidental Discovery of Fibrous Obliteration of an Appendiceal Diverticulum

Diverticulosis of the appendix (DA) is rare and frequently found incidentally. Some cases are discovered after presenting with similar symptomatology to acute appendicitis, whereas other cases may be completely silent. Fibrous obliteration (FO) is a histologic finding indicative of cellular proliferation secondary to relapses of subclinical inflammatory processes. We report a case of a 75-year-old female with a history of chronic, intermittent abdominal pains who presented to the general surgery clinic after an abnormal thickening of the appendix was discovered on abdominal and pelvic computed tomography imaging. The patient underwent laparoscopic appendectomy for suspicion of malignancy. The histologic evaluation of the specimen demonstrated a diverticulum at the distal end of the appendix with FO of the lumen. We suspect the chronic nature of her disease course may have led to the FO of the diverticulum. An extensive literature search was performed, which revealed no other cases of FO of appendiceal diverticula. This may be the first case of diverticulosis of the appendix with FO in the English medical literature. If DA is discovered early with non-invasive imaging, surgical excision should be performed prophylactically as an association with an increased risk of perforation and neoplastic progression has been found.

Diverticular Disease of the Appendix Is Associated with Complicated Appendicitis

INTRODUCTION

Diverticular disease of the vermiform appendix (DDA) has an incidence of 0.004 to 2.1% in appendicectomy specimens. DDA is variably associated with perforation and malignancy. We report a single-center experience of DDA. The primary aim is to validate the association of DDA with complicated appendicitis or malignancy, and the secondary aim is to validate systemic inflammatory response syndrome (SIRS) criteria and quick Sepsis-related Organ Failure Assessment (qSOFA) scores.

METHODS

The histopathology reports of 2,305 appendicectomy specimens from January 2011 to December 2015 were reviewed. Acute appendicitis was found in 2,164 (93.9%) specimens. Histology of the remaining 141 (6.1%) patients revealed: normal appendix (n = 110), DDA (n = 22), endometriosis of appendix (n = 6), and an absent appendix (n = 3). Patient demographics, clinical profile, operative data, and perioperative outcomes of DDA patients are studied. Modified Alvarado score, Andersson score, SIRS criteria, and qSOFA scores were retrospectively calculated.

RESULTS

The incidence of DDA was 0.95%. Ten patients (45.5%) had diverticulitis. The mean age of DDA patients was 39.5 years (range 23-87), with male preponderance (n = 12, 54.5%). The median Modified Alvarado score was 8 (range 4-9), and the median Andersson score was 5 (range 2-8). Fourteen patients (63.6%) had SIRS, and none had a high qSOFA score. Eight patients (36.4%) had complicated appendicitis (perforation [n = 2] or abscess [n = 6]). Eleven (50%) patients underwent laparoscopic appendicectomy. There were three 30-day readmissions and no mortality.

CONCLUSION

DDA is a distinct clinical pathology associated with complicated appendicitis.

Macroscopic and microscopic characteristics of low grade appendiceal mucinous neoplasms (LAMN) on appendectomy specimens and correlations with pseudomyxoma peritonei development risk

Low grade appendiceal mucinous neoplasm (LAMN) is the primary source of pseudomyxoma peritonei (PMP). PMP may develop after seemingly complete resection of primary tumor by appendectomy, which is unpredictable due to lack of reliable prognostic indicators. We retrospectively reviewed 154 surgically resected LAMNs to explore if any of the macroscopic and microscopic characteristics may be associated with increasing risk of PMP development. Our major findings include: (1) As compared to those without PMP, the cases that developed PMP were more frequent to have (a) smaller luminal diameter (<1 cm) and thicker wall, separate mucin aggregations, and microscopic perforation/rupture, all suggestive of luminal mucin leakage; (b) microscopic acellular mucin presenting on serosal surface and not being confined to mucosa; and (c) neoplastic epithelium dissecting outward beyond mucosa, however, with similar frequency of neoplastic cells being present in muscularis propria. (2) Involvement of neoplastic cells or/and acellular mucin at surgical margin did not necessarily lead to tumor recurrence or subsequent PMP, and clear margin did not absolutely prevent PMP development. (3) Coexisting diverticulum, resulted from neoplastic or non-neoplastic mucosa being herniated through muscle-lacking vascular hiatus of appendiceal wall, was seen in a quarter of LAMN cases, regardless of PMP. The diverticular portion of tumor involvement was often the weakest point where rupture occurred. In conclusion, proper evaluation of surgical specimens with search for mucin and neoplastic cells on serosa and for microscopic perforation, which are of prognostic significance, should be emphasized.

Systematic review and meta-analysis of the association between diverticulosis of the appendix and neoplasia

BACKGROUND

Diverticula of the appendix (DA) are infrequent and their clinical implications are often overlooked. Several studies have found a significantly increased prevalence of neoplasms in appendiceal specimens with diverticula. Despite the potential clinical implications, there is a paucity of literature. A systematic review and meta-analysis was performed to evaluate the prevalence of DA and its association with neoplasia.

METHODS

A systematic search of literature (Cochrane, EMBASE, PubMed and Medline) reporting the prevalence of DA and association with neoplasia was performed in November 2019. Relevant articles were assessed in accordance with the PRISMA guidelines. Risk of bias assessment was carried out using modified Newcastle-Ottawa scale. Meta-analysis with risk ratio and random-effects model was performed using RevMan.

RESULTS

The initial search identified 1122 potential articles of which 11 were appropriate for quantitative analysis. The prevalence rate of DA was 1.74%. The mean age of patients with DA and those without DA was 41.2 and 33.9 years, respectively. The ratio of male to female was 1.8:1. The prevalence of neoplasia in specimens without DA versus those with DA was 1.28% and 26.94%, respectively. Only four studies addressed the prevalence of locoregional neoplasia in the setting of DA compared to control. Meta-analysis with random-effects model demonstrated that pooled risk ratio was 25.46 (95% confidence interval 12.77-50.75, P < 0.00001).

CONCLUSION

The strong association with neoplasia in this meta-analysis reinforces the clinical significance of DA. Surgeons, pathologists and radiologists should be mindful of this uncommon pathology and consider individualized patient management, until further evidence can direct clinical guidelines for the management of patients with DA.

Clinical characteristics of appendiceal diverticular disease

BACKGROUND

Appendiceal diverticular disease (ADD) is a rare pathology which is associated with an increased mortality risk due to rapid perforation and high rates of neoplasm. In our study, we aimed to evaluate the clinical and histopathological characteristics of ADD with differences from acute appendicitis (AA) diagnosis and to determine the association with neoformative processes.

METHODS

The 4279 patients who underwent appendectomy were evaluated retrospectively. ADD patients histopathologically classified into four groups. Patients' demographic characteristics, imaging and preoperative laboratory findings, additionally postoperative histopathology results were compared between groups.

RESULTS

The prevalence of ADD was 2.29% (n = 98). In addition, the male/female ratio was 2.37 in ADD patients who were found to be significantly older than those with AA patients. Type III was the most frequently (62.2%) identified sub-group of ADD. The incidence of neoplasms, plastrone, and Littre's hernia was found statistically higher in ADD group than AA group. Mucinous adenomas (10.2%) was the most common neoplasm while the carcinoid tumor (1%) and precancerous serrated adenomas (4.1%) were also reported.

CONCLUSIONS

As a result, high neoplasm in ADD patients can be shown with incidence of perforation and plastron, and in order to avoid possible neoplasm or major complications, it is necessary to carry out new studies for the right diagnosis of ADD whether the diagnosis is done preoperatively or ıntraoperatively. We recommend surgical resection of the ADD, which may even be incidentally detected during any surgical procedure, due to its high risk of neoplasm and rapid perforation.

Clinical significance of appendiceal diverticulum: a significant marker for appendiceal neoplasia in Australian patients

INTRODUCTION

Diverticula of the appendix (DA) have a reported incidence of up to 2.1%. They are primarily detected incidentally, through imaging and intraoperative or histologic diagnosis. This study's objective was to examine the prevalence of DA, and its relationship with inflammation and neoplasia, as well as review the literature with respect to clinical outcomes and ability to identify DA preoperatively.

METHODOLOGY

A retrospective search of all patients undergoing an appendicectomy for right lower quadrant pain at a single institution between 2004 and 2017 was conducted. Histopathology reports for evidence of DA, location of the DA, presence of inflammation, and any relationship between DA and neoplasms (adenoma, carcinoma, carcinoid, lymphoma, and mucinous neoplasm) within the appendix were reviewed. Clinical notes, operative records, and preoperative imaging were also reviewed.

RESULTS

Two thousand seven hundred eleven patient were included in the study, with a mean age of 34 years, with acute appendicitis found in 82.5%. 31.6% of patients with DA had associated inflammation of the DA. DA was present in 57 patients (2.1%), with 55 patients in the total cohort having neoplasia (2.0%). Patients with DAs were ten times more likely to have appendicular neoplasm than patients without a DA (17.5 vs 1.8%; p < 0.0001, OR 11.8 95%, CI 5.6-24.8).

CONCLUSION

This is the first Australian study demonstrating DAs are a significant marker of appendiceal neoplasm. Appendicectomy in all incidentally discovered diverticulum should be considered. Due to a paucity of data, research is required into this area to assess for the need for endoscopy following diagnosis.

Appendiceal diverticulosis: a harbinger of underlying primary appendiceal adenocarcinoma?

Diagnosis of primary appendiceal adenocarcinoma (PAA) is hindered by its rarity and largely asymptomatic nature. Appendiceal diverticulosis (AD) is equally rare. We report an unusual case of PAA presenting with perforated appendiceal diverticulitis, and discuss a review of the literature about its association, and its surgical and pathological implications. A middle-aged man was admitted with right iliac fossa (RIF) pain and a corresponding tender abdominal mass for 5 days. Computerised tomography (CT) scan demonstrated a thickened appendix with 3 cm abscess at its base. During laparoscopic appendicectomy, the appendiceal phlegmon was adhered to the surrounding bowel. Histology showed a perforated diverticulum near the appendiceal tip, and a primary appendiceal well-differentiated adenocarcinoma located proximal to it with clear margins. Up to 48% of ADs are associated with appendiceal neoplasms, but its coexistence with PAA is reported in fewer than ten instances worldwide. Obstructing appendiceal tumours, by raising intraluminal pressure, can predispose to AD formation. Intestinal-type PAA is often managed like its colorectal counterpart, although controversies about management of PAA in a perforated AD remain. Recognition of the association of AD and PAA is critical to ensure meticulous oncological resection and histological examination.

Unexpected histopathology of acute appendicitis

INTRODUCTION

Appendicular diverticula and associated diverticulitis is a rare disease. Patients present commonly with symptoms of acute appendicitis and require laparoscopic or open surgery. Diagnosis is usually made only on histology. Here, we present a rare case of acute diverticulitis of the appendix.

CASE PRESENTATION

A 33-year old gentleman presented with right iliac fossa pain of 3 days duration. On admission, appendicitis was diagnosed on Computerized Tomography (CT) scan and laparoscopic appendicectomy was subsequently performed. Intra-operative findings were unremarkable and recovery was uneventful. Histopathology however revealed diverticulitis of appendix with acellular mucin.

DISCUSSION

Acute diverticulitis of the appendix is an exceptionally rare condition and reported in 0.004%-2% of appendicectomies. It presents usually when complicated with perforation and bleeding. There is however a strong association with certain malignancies such as mucinous neoplasm, carcinoid and Pseudomyxoma peritoneii. Radiological proven appendicular diverticulum requires early intervention due to higher chance of diverticulitis related complication. Surgeons should be aware about this rare disease and may consider elective surgery in view of potential risk of complications and malignancy.

CONCLUSION

We concluded that because of strong malignant association, it would be recommended that all appendix specimens should inspect during and after surgery and concurrent examination of peritoneal cavity is recommended.

Appendiceal diverticulitis, a rare relevant pathology: Presentation of a case report and review of the literature

INTRODUCTION

Appendiceal diverticulitis is a rare pathology that mimics acute appendicitis. Appendiceal diverticula are classified into congenital and acquired with difference in incidence and pathogenesis. Appendiceal diverticulitis is often overlooked because of mildness of symptomatology with increasing risk of complications, such as perforation. Appendiceal diverticula are often associated to higher risk of neoplasm especially carcinoid tumors and mucinous adenomas.

PRESENTATION OF CASE

A 40-year-old caucasic male presented into Emergency Room with right lower quadrant pain associated with vomit, abdominal tenderness, fever and moderate leukocytosis (11.93×10; neutrophils 78.5%). Acute appendicitis was suspected and a surgical approach was chosen with a McBurney access. The removed specimen (Figs. 1 and 2) was 11cm long with multiple hyperaemic and oedematous diverticular protrusions. The postoperative course was regular. Discharging was on 4th postoperative day in optimal clinical conditions. The histological examination (Fig. 3) showed acute inflammation of appendiceal pseudodiverticula with acute peridiverticulitis and abscess.

DISCUSSION

Currently, appendiceal diverticulitis is often overlooked with high risk of complications, above all perforation. Attention should be kept during the surgical procedure and the patholological examination in order to identify any associated neoplasm.

CONCLUSION

Appendiceal diverticulitis should be considered in adult male patients with right lower quadrant pain or tenderness. Accurate appendectomy should be performed in order to permit an appropriate pathological examination and possible associate neoplasm should always be searched through. Prophylactic appendectomy should be performed in case of incidental finding of appendiceal diverticula in asymptomatic patients in order to avoid the high perforation risk.

A case report describing diverticulosis of the appendix presenting as acute appendicitis

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A case is described of a patient with diverticulosis of the appendix (DA) which was initially diagnosed as early acute appendicitis.

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The clinical characteristics of DA are described and a case is made for better diagnosis prior to surgery.

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Improving preoperative diagnosis of DA will require higher indices of clinical suspicion based on patient presentations and better identification by diagnostic imaging (CT and ultrasound).

Introduction

Diverticulosis of the appendix (DA) is a rare clinical finding which is often confused with acute or chronic appendicitis and is usually only identified during or after appendectomy. The symptoms of DA can last for up to two weeks and laboratory studies tend to reflect a more chronic inflammation. Distinguishing the two entities is important as DA has a higher risk for perforation and may be associated with an underlying malignancy.

Presentation of case

A 54­-year old African­-American male presented with three­-days of right sided abdominal pain, nausea, and vomiting. Physical exam and abdominal CT imaging were concerning for early acute appendicitis. The patient was taken emergently to the operating room for laparoscopic appendectomy. Extensive adhesions were found around the Appendix which was grossly abnormal with multiple diverticula. The patient had an uneventful recovery.

Discussion

Patients with DA are often misdiagnosed with chronic or acute appendicitis based on their presenting symptoms and imaging. While appendectomy is the definitive treatment, diagnosing DA before surgery is important in determining the patient's risks and potential complications.

Conclusion

Diverticulosis of the Appendix is a rare clinical entity which is often misdiagnosed. Better imaging techniques and higher indices of clinical suspicion are needed to make the appropriate diagnoses before patients are taken for surgery.

Perforated appendiceal diverticulitis associated with appendiceal neurofibroma in neurofibromatosis type 1

An appendiceal neurofibroma (ANF) is a rare neoplasm associated with neurofibromatosis type 1(NF-1), an inheritable neurocutaneous disorder that involves multiple systems including the intraabdominal organs. Appendiceal diverticulitis occasionally ruptures in the absence of intense abdominal pain, which can lead to serious consequences. Recent reports highlight the association between appendiceal diverticulum and appendiceal neoplasms; however, there is still little information on the association between appendiceal diverticulitis and ANF in NF-1. A 51-year-old Japanese male with NF-1 was referred to the division of surgery for mild right lower quadrant pain. It was suspected he had perforated acute appendicitis with periappendiceal abscess based on clinical manifestations and findings of computed tomography. An emergency appendectomy was conducted. The pathological examination revealed diffusely proliferated tumor cells of a neurofibroma, coexistent with multiple appendiceal diverticulums, leading to the diagnosis of perforated appendiceal diverticulitis associated with ANF. Although he developed a remnant abscess, he recovered with the conservative treatments of antibiotics and drainage. This case suggests that appendiceal diverticulitis might be a complication of appendiceal involvement of NF-1, and that it occasionally ruptures in the absence of intense abdominal pain. Clinicians should recognize that NF-1 can cause various abdominal manifestations.

Clinical implications of diverticular disease of the appendix. Experience over the past 10 years

BACKGROUND

Diverticular disease of the appendix is an uncommon condition, with an incidence from 0.004 to 2.1%. It usually occurs between the fourth or fifth decades of life, does not present gastrointestinal symptoms but only insidious abdominal pain. Patients usually delay consultation, leading to increased morbidity and mortality. The aim of this study was to determine the clinical features of diverticular disease of the appendix.

METHODS

A retrospective study of all patients undergoing appendectomy in a tertiary hospital between September 2003 and September 2013 was performed.

RESULTS

During this period, 7,044 appendectomies were performed, and 42 cases of diverticular disease of the appendix were found, which represents an incidence of 0.59%. A total of 27 patients were male. The mean age was 46.6±21 years. The average hospital stay was 4.5 days. A perforated appendix was identified in 46% of patients. In 80% of the cases, a complementary imaging test was performed. The incidence of neoplastic disease with diverticulum of the appendix was 7.1%.

CONCLUSIONS

Diverticular disease of the appendix is an incidental finding. In its acute phase, it presents as an acute appendicitis. The treatment of choice is appendectomy. It presents a higher risk of developing neoplastic disease of the appendix.

Clinicopathological study of 25 cases of diverticular disease of the appendix: experience from farwaniya hospital

Background. Diverticular disease of the appendix (DDA) is a rare disease and it has been shown to be associated with locoregional neoplasms. This study was conducted to characterize clinicopathological features and to investigate its association with appendiceal neoplasms. Methods. We searched the records of the Department of Pathology at Farwaniya Hospital for cases of diverticular disease of the appendix between 2003 and 2011. Histological slides and patient charts were reviewed for relevant information. Consecutive cases of acute appendicitis were selected as a control group. Results. We identified 25 cases of DDA, 24 of which occurred in men. Mean age of DDA patients was 35 ± 10.1 years and was significantly greater than that of appendicitis patients (P = 0.027). The mean temperature of cases (37.9°) was significantly higher (P = 0.012) than that of the controls (37.3°). The cases had lower white blood cell (WBC) counts compared to controls (13.6 versus 16.7, P = 0.04). Pathological diagnosis identified 4 cases of diverticulosis, 5 cases of diverticulitis, 6 cases of diverticulosis with acute appendicitis, and 10 cases of diverticulitis and appendicitis. None of the cases was associated with any type of neoplasm. Conclusions. DDA is a rare disease, and clinicians and radiologists should be aware of it. Male sex and adult age seem to be risk factors associated with DDA. The disease may not have any direct association with any neoplasm.

Appendiceal Mucosal Schwann Cell Proliferation

Recognition of an appendiceal diverticulum is important because of its association with an appendiceal neoplasm. The incidence of mucosal Schwann cell proliferation in 24 cases of appendiceal diverticular disease, 17 serrated polyps, 4 cases of mucosal hyperplasia, and 45 normal appendices was determined. Ten (42%) of 24 cases with diverticula, 2 (50%) of 4 cases of mucosal hyperplasia with concurrent surface low-grade dysplasia, and 9 (20%) of 45 cases of normal appendices showed mucosal Schwann cell proliferation. It was not seen within the 17 cases of serrated polyps. Mucosal Schwann cell proliferation is common in appendiceal diverticular disease and may serve as a histologic marker for the presence of an appendiceal diverticulum. Thus, when routine histologic sections of a removed appendix demonstrate Schwann cell proliferation, further examination of the specimen may detect possible coexisting diverticular disease, which in turn may be associated with appendiceal neoplasms and epithelial dysplasia.