Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “APPENDIX”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 181 records · Page 10Linked to original sources
PubMed1980

Germinal centres and the B cell system. III. Germinal centre forming capacity of rabbit appendix germinal centre (-derived) cells.

Following appendectomy and sublethal (450 rads) whole body X-irradiation, reconstitution with autologous appendix germinal centre cells led to excellent germinal centre formation in the recipient's spleen. Heat killing of the cells to be injected completely abolished this phenomenon. Apparently a suspension of appendix germinal centre cells contains a (sub)populations of cells capable of germinal centre formation (Germinal Centre Precursor Cells). Following whole body X-irradiation while shielding the appendix, germinal centre activity could only be detected after antigenic stimulation in otherwise normally regenerated splenic follicular structures. This suggests that the cell population recently derived from appendix germinal centres is able to function once again as a population of germinal centre precursors.

Animals↗
PubMed1998

[Perforated diverticulum of the vermiform appendix].

Diverticulitis of the vermiform appendix is an often disregarded disease. Diagnosis follows after appendectomy due to inflammatory complications in the form of diverticulitis and appendicitis. Diverticula can also be found as a reason for complaints in histologically unaltered appendix or as an incidental finding. Diverticula of the vermiform appendix are classified as false (acquired) or true (congenital). We report on the case of a 57-year-old man with a perforated appendix diverticulum as reason for peritonitis and a paralytic ileus of the colon and small intestine.

Appendectomy↗
PubMed2000

Macroscopic assessment of the appendix at diagnostic laparoscopy is reliable.

BACKGROUND: Healthy-looking appendixes are often removed at laparoscopy for suspected appendicitis. This practice may have adverse secondary effects. METHODS: We reviewed the literature for the years 1978 to 1998 to analyze the negative appendectomy rates, complication rates, the accuracy of laparoscopic appendix assessment, and the incidence of false negative diagnosis of appendicitis at surgical and gynecological laparoscopy. RESULTS: The respective negative appendectomy rates were 22% and 15% in studies that compared laparoscopic with open appendectomy. The appendix was left in situ in 37% of 4,281 surgical diagnostic laparoscopies. There were instances of missed appendicitis among the 3,367 gynecological diagnostic laparoscopies performed on women for lower abdominal pain, and there were 188 appendectomies in this group. Studies comparing the macroscopic appearance of the appendix at operation with microscopic findings from the excised specimen had a false negative error rate of 3%. CONCLUSIONS: Contrary to general opinion, there is no substantial evidence to support the assumption that the macroscopic diagnosis of appendicitis is unreliable. High rates of conflicting diagnoses of excision specimens suggest that endoappendicitis has little clinical significance. At present, negative appendectomy rates are considerably higher for laparoscopic appendectomy than for the open approach. The role of diagnostic laparoscopy in suspected appendicitis should be reconsidered. It may be useful in particular subgroups of patients, but it is no substitute for good clinical judgment. Furthermore, it is not always necessary to perform an incidental appendectomy.

Appendectomy↗
PubMed2006

Myxoglobulosis of the appendix associated with a proximal carcinoid and a pseudodiverticulum.

A 37-year-old woman presented with acute right lower abdominal pain. Intraoperatively, the appendix was enlarged and distended. The lumen of the appendix was tightly filled with pearl-like globules, diagnostic of myxoglobulosis, a rare variant of mucocele of the appendix. A carcinoid of 2.0 cm diameter was found in the proximal region of the appendix. The appendiceal mucosa showed hyperplastic-adenomatous changes. A pseudodiverticulum interpreted as evidence of increased intraluminal pressure was detected. The latter may be an adjunct to the proximal partial obstruction of the appendiceal lumen by the carcinoid in the development of the spheroids of myxoglobulosis.

Adult↗
PubMed2005

CD5+ B cells are preferentially expanded in rabbit appendix: the role of CD5 in B cell development and selection.

Although only a small proportion of mouse and human B cells are CD5(+), most adult rabbit B cells express CD5. However, CD5 was not detectable on the majority of B cells in neonatal appendix 1 and 3days after birth. Cell trafficking studies demonstrated that CD5(+) and CD5(-) CD62L(+) B cells from bone marrow migrated into appendix. There, CD5(+) B cells were preferentially expanded and predominated by approximately 2weeks of age. In mutant ali/ali rabbits, VHa2(+) B cells develop through gene conversion-like alteration of rearranged VH genes upstream of deleted VH1a2. Correlated appearance of individual CD5(+) germinal centers and VHa2(+) B-cells in mutant appendix suggests that CD5 binding positively selects cells with a2(+) framework regions that bind CD5. Following negative and positive selection, cells with diversified rearranged heavy- and light-chain sequences exit appendix, migrate to peripheral tissues and constitute the preimmune repertoire of CD5(+) B cells that encounter foreign antigens.

Amino Acid Sequence↗
PubMed1999

Sonographic detection of normal and abnormal appendix.

AIM: The aim of the study was to assess the value of sonography in detecting the normal appendix and in identifying abnormality. METHODS: The appendiceal wall thickness (normal: <3 mm) and ultraluminal contents (abnormal: large appendicolith, non-expressible fluid) were used as the primary criteria to determine the appendiceal status in 716 appendices. In patients who underwent appendicectomy (n = 166), surgical and histopathological findings were correlated with the ultrasound (US) findings; in patients who did not have surgery the reference standard was the clinical consensus based on follow-up. RESULTS: Thirty-four patients out of 179 with abnormal sonographic findings did not undergo appendicectomy and recovered spontaneously; in 22 of these, the US changes were confined to the appendiceal tip. A normal appendix was identified in 537 patients (45.9% of all patients without appendicitis), with histologic verification subsequently obtained in 21. In 76 normal appendices (14.2% out of all normal appendices), luminal dilatation due to non-expressible inspissated faeces resulted in appendiceal outer diameter >6 mm (range, 6.2-12 mm); a histopathologic proof of non-inflamed appendix was obtained in seven of these. CONCLUSIONS: A normal appendix can be visualized in a high percentage of cases and it may present with an outer diameter >6 mm (the widely-accepted upper limit of normal) due to the inspissated faecal material within the lumen. A significant percentage of early appendicitis can resolve spontaneously, especially when confined to the appendiceal tip.

Acute Disease↗
PubMed2006

Long-term followup of the intussuscepted ileal nipple and the in situ, submucosally embedded appendix as continence mechanisms of continent urinary diversion with the cutaneous ileocecal pouch (Mainz pouch I).

PURPOSE: We analyzed stoma related complications and continence rates in patients who underwent continent urinary diversion with the cutaneous ileocecal pouch (Mainz pouch I). We compared the intussuscepted ileal nipple and in situ, submucosally embedded appendix as continence mechanisms. MATERIALS AND METHODS: A total of 401 patients were included in a retrospective followup study. Continence mechanisms were the intussuscepted ileal nipple in 205 patients and the in situ, submucosally embedded appendix in 196. RESULTS: A total of 144 patients (36%) required intervention for a stomal complication. Of patients who received an intussuscepted ileal nipple 34 (17%) had stomal stenosis at a mean time to first stenosis of 43.8 months, 41 (20%) had stones at a mean interval to the first stone of 62.8 months, 12 underwent reoperation for stomal incontinence, including 1 because of nipple necrosis, and 82% were completely continent. Of patients who received an in situ, submucosally embedded appendix 63 (32%) had stomal stenosis at a mean time to first stenosis of 31.4 months, 20 (10%) had stones at a mean interval to the first stone of 47.5 months, 3 underwent reoperation for stomal incontinence, 4 had appendiceal necrosis and 92% were completely continent. CONCLUSIONS: Of stomal complications 63% were treated endoscopically. The higher rate of stomal stenosis with the appendiceal stoma is most likely due to the smaller diameter of the appendix. The higher rate of stone formation in patients with the intussuscepted ileal nipple is related to metal staples. Continence rates of the 2 outlets are good with somewhat larger amounts of mucous secretion from the larger stoma of the intussuscepted ileal nipple.

Adolescent↗
PubMed1993

Characteristics and use of the in situ appendix as a continent catheterization stoma for continent urinary diversion in adults.

Use of the in situ appendix to provide continence was evaluated in 21 adults undergoing continent urinary diversion. The appendix with minimal or no manipulation was used in 20 of the 21 adults to provide the continence mechanism. Our findings indicate that in the majority of adults with no prior appendectomy the unaltered or minimally altered appendix is suitable to provide continence, and that dilating a narrow appendix is safe, effective and compatible with providing an adequate continence mechanism.

Adult↗
PubMed2001

Goblet cell carcinoid of the appendix: Investigation of the expression of beta-catenin and E-cadherin.

Goblet cell carcinoids are rare neoplasms that predominantly occur in the appendix. In this report we present a case of goblet cell carcinoid of the appendix. A 58-year-old male patient complaining of pain in the right lower quadrant was diagnosed with acute appendicitis and underwent an appendectomy. Histological examination of the resected appendix revealed goblet cell carcinoid. Infiltration of tumor cells beyond the appendix was observed and the surgically resected margin was positive for tumor cells. Carcinoembryonic antigen (CEA) was diffusely detected by immunohistochemistry, and cytokeratin 20, neuron-specific enolase (NSE), chromogranin A and serotonin were focally observed in the tumor cells. The expression of beta-catenin and E-cadherin was investigated to compare with that of typical rectal carcinoids (n = 3) and colon adenocarcinomas (n = 3). In normal colonic and rectal mucosae, beta-catenin and E-cadherin stained positive on the plasma membrane. In the case reported here, beta-catenin showed a preserved expression on the plasma membrane of goblet cell carcinoid; a pattern similar to typical carcinoids rather than to adenocarcinomas. However, E-cadherin demonstrated a reduced expression on the plasma membrane of the tumor cells. This staining pattern was identical to those both of carcinoids and of adenocarcinomas. These findings suggest the possibility that, in some cases, the adherens junctions of goblet cell carcinoids are similar to those of typical carcinoids rather than to those of adenocarcinomas.

Appendix↗
PubMed2004

Appendicitis and infections of the appendix.

The pathologic spectrum of the acutely inflamed appendix encompasses a wide range of infectious and noninfectious entities. The appendix suffers alone in some of these disorders, and in others may be involved through extension from other areas of the gastrointestinal tract. Although the appendix is the most commonly resected and examined intraabdominal organ, the pathogenesis and etiology of acute nonspecific appendicitis (the most common diagnosis made in this organ) remains enigmatic. This review encompasses the pathology, pathogenesis, and bacteriology of acute appendicitis, as well as controversial issues such as the diagnosis of chronic appendicitis and the significance of a morphologically unremarkable appendectomy specimen in the clinical context of appendicitis. In addition, the pathologic features, pertinent diagnostic techniques, and clinical significance of several specific bacterial, viral, fungal, and parasitic infections affecting the appendix are presented, including adenovirus, cytomegalovirus, Yersinia species, actinomycosis, Mycobacteria species, histoplasmosis, pinworms, schistosomiasis, and Strongyloides stercoralis.

Appendicitis↗
PubMed2002

The use of pedicled appendix graft for substitution of urethra in recurrent urethral stricture.

BACKGROUND: Recurrent posterior urethral strictures after failed urethroplasty may need urethral substitution. Skin or mucosal grafts, currently used for this purpose, have a high complication rate. The authors describe the use of pedicled appendix for posterior urethral substitution. METHODS: Two boys with pelvic fracture urethral distraction injuries were treated for recurrent posterior urethral strictures after a failed perineal anastomotic urethroplasty. Through a perineal-transpubic approach the stricture tissue was excised, which resulted in a gap of 5 to 7 cm between the healthy ends. The vermiform appendix was mobilised on its own pedicle and transposed to the perineum; the proximal end of appendix was anastomosed to the prostatic urethra and the distal end (tip discarded) to the bulbar/penile urethra. Omentum was transposed to wrap the anastomosis and fill the dead space. RESULTS: Normal micturition was restored in both patients. No further treatment was required after 1 dilatation in the first case. Both patients are continent. Potency status remains unchanged from the preoperative period with normal erections in 1 case. Follow-up (1 to 3 years) has been satisfactory with no complications. CONCLUSIONS: The appendix is a promising organ for posterior urethral replacement. It can be brought to the perineum on its own vascular pedicle.

Adolescent↗
PubMed2005

Appendix as a biliary conduit for choledochal cysts in children.

Biliary conduits are constructed in operations for choledochal cysts. A wide variety of options are available for biliary tract reconstruction. We present our experience of treating six children with choledochal cysts by using the appendix as a biliary conduit. After mobilizing the appendix on its vascular pedicle, nonrefluxing, tunneled anastomosis was made with the 2nd part of the duodenum and the appendix. The operative procedure was simple and less time-consuming. Postoperative evaluation was done with the help of HIDA scan and ultrasound examination. Postoperative cholangitis was conspicuously absent in the two years of follow-up. One child has been lost to follow-up. From our preliminary experience, the operation seems simple and satisfying. Though the long-term efficacy still remains to be proven, the appendix should prove durable as a functional conduit.

Anastomosis, Surgical↗
PubMed2002

Different beta-catenin immunoexpression in carcinoid tumors of the appendix in comparison to other gastrointestinal carcinoid tumors.

Carcinoid tumor of the appendix is an endocrine tumor that is histologically similar to, but biologically less aggressive than carcinoids arising from other parts of the gastrointestinal tract. In this study, we examined E-cadherin, beta-catenin, DCC, p53 and Ki67 immunoexpression in cases of carcinoid of the appendix and made a comparison with non-appendiceal carcinoid tumors. Nine cases of appendiceal carcinoid and 11 biopsies of carcinoid of other parts of the gastrointestinal tract, five cases of the small intestine and six of the stomach were immunohistochemically evaluated for Ki67, p53, DCC, E-cadherin and beta-catenin. Two main patterns of beta-catenin staining were observed. The first pattern was characterized as membranous and cytoplasmic, and was seen mainly in the peripheral cells of the nests. The second pattern was diffuse, predominantly membranous. Most (five of seven) appendiceal carcinoids and only three of 11 non-appendiceal cases showed the first staining pattern (p < 0.05). Immunoexpression of E-cadherin and DCC was similar in both groups. p53 and Ki-67 immunostaining revealed stronger nuclear positivity in the non-appendiceal carcinoid tumors (statistically not significant). We found a pattern of beta-catenin immunostaining in typical carcinoid tumors of the appendix that was different from the pattern seen in non-appendiceal carcinoid tumors. This alteration suggests that carcinoid of the appendix may represent a different subtype of carcinoid tumors with different immunohistochemical and biological behavior.

Adult↗
PubMed1979

Primary Crohn's disease of the appendix: report of 14 cases and review of the literature.

Fourteen patients with primary Crohn's disease of the appendix have been seen in a 12 year period. These patients represent 12.8% of the total number undergoing surgical resection because of Crohn's disease. Twenty-three cases of appendiceal Crohn's disease have been previously reported in the literature. A correct preoperative diagnosis is rarely made; the usual diagnosis is that of acute appendicitis or appendiceal abscess. The removed appendix in twelve of our 14 cases had marked thickening of the wall with transmural fibrosis and often with granulomatous inflammation. The enlarged appendix had an external appearance similar to that of ileal Crohn's disease, and we consider a correct surgical diagnosis might be possible with better awareness of its existence. The diagnosis might be suspected earlier when the clinical course of apparent appendicitis is protracted or atypical. Contrary to the previous estimation of high recurrence rate, this series and the cumulative evidence in the literature show a relatively low rate at 14%. The feared fistula formation following the removal of the appendix has not been seen in either our series or the literature. These patients, however, merit long-term follow-up.

Adolescent↗
PubMedDate not supplied

Computed tomography of the abnormal appendix.

This report describes the CT features of 29 abnormal appendices visualized during abdominal CT examinations. There were 22 cases of acute appendicitis, five mucoceles, and two mucinous adenocarcinomas of the appendix. The inflammed appendix appeared either as a fluid-filled slightly distended structure or as a collapsed small tubular structure. It was visualized on either cross or longitudinal sections and showed slight circumferential wall thickening. Periappendiceal inflammation was detected in 19 cases and intraluminal appendicoliths in six cases. Mucocele appeared as a larger fluid-filled round, oval, or tubular structure having a thin, sharp wall, low density contents, and no periappendiceal inflammation. Mucinous carcinoma appeared either as a single or as multiloculated, irregular shaped cystic lesion with solid elements. Infiltration of cecum and terminal ileum was seen in one case. In five cases the abnormal appendix was not recognized initially and was identified only after repeat 5 X 5 mm sections were obtained. During CT examination, demonstration of an abnormal appendix establishes the source of the abdominal pathology and helps greatly in the differential diagnosis.

Acute Disease↗
PubMed1981

Appendicitis in a barium-filled appendix.

Fourteen cases of appendicitis developing in an appendix with prolonged retention of barium have been previously described. A 15th case is herein presented. Present reports are inadequate to determine the normal period of retention of barium in an appendix after contrast study. No conclusions can be drawn as to whether the retained barium causes appendicitis by a sequence of events or whether the retained barium merely demonstrates a previously existing abnormality in the appendix or has no pathologic significance. A patient in whom barium is retained in the appendix should, as a minimum step, be informed that appendicitis may develop and that he should consult his physician if abdominal symptoms develop. Interval appendectomy for the asymptomatic patient with prolonged retention of barium cannot be justified by the present body of case reports.

Adult↗
PubMed2004

Comparative study of the Yang-Monti channel and appendix for continent diversion in the Mitrofanoff and Malone principles.

PURPOSE: Continent conduits for Mitrofanoff and Malone procedures are widely used for incontinence management. Because the appendix is not always suitable or available, Monti proposed a transversely retubularized short segment of ileum. We present our experience and compare outcomes according to the type of conduit. MATERIALS AND METHODS: In a retrospective study from 1988 to 2003 case notes were reviewed specifying conduit characteristics, underlying disease, overall surgical management of incontinence and subsequent complications. Comparison was based on followup, details of complications and treatments. RESULTS: In 32 men and 14 women with a total of 65 conduits (Mitrofanoff in 41 and Malone procedure in 24) the condition was spina bifida in 29, bladder exstrophy in 5 and sacral agenesia in 3. Other cases included various origins. Mean age at operation was 14.2 years (range 1 to 31). Mean followup was 5.3 years (range 1 to 14.7). Appendix was used in 23 cases and a Yang-Monti channel was performed in 18 (ileum in 7 and sigmoid in 11) for urinary diversion. The Malone procedure was performed using appendix in 11 cases and a Yang-Monti tube in 13. At followup 61 conduits (93.8%) were in use and 4 (6.2%) were abandoned. Complications were cutaneous stenosis, kink blockage and stomal leakage. No significant differences were observed between the types and purposes of the conduit. CONCLUSIONS: With constant availability and various possibilities of construction the Yang-Monti channel is recommended for continent diversion creation when appendix does not look suitable or is already in use or absent.

Adolescent↗
PubMed1992

Benign epithelial neoplasms of the appendix: classification and clinical associations.

The nomenclature of non-carcinoid epithelial proliferations of the appendix is confused and many of the terms used have no histogenetic basis. A classification based on the well-established diagnostic categories of colonic epithelial polyps has been proposed recently. We have applied this classification to 42 benign epithelial lesions of the appendix in order to determine its suitability for routine diagnostic use, and in order to determine the prognosis of patients with these lesions. All lesions could be classified as either hyperplastic, adenomatous, mixed hyperplastic/adenomatous or dilated appendices. Six cases were associated with a synchronous carcinoma of the colon with all types of appendiceal histology being represented. Follow-up of the remainder of the patients revealed two subsequent colonic carcinomas, at 3 and 6 years post-appendicectomy respectively. In both of these patients, the appendix had shown adenomatous epithelium. We suggest that adenomas of the appendix may have a similar prognostic significance to adenomas elsewhere in the large bowel.

Adult↗