PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Appendix”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

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

At least 253 records · Page 14Linked to original sources

Endoscopic removal of an intussuscepted appendix mimicking a polyp--an endoscopic hazard.

A 55-yr-old white woman with a polypoid filling defect in the caput cecum, on barium enema examination, had endoscopic removal of this mass. This was immediately recognized macroscopically to be an intussuscepted appendix. This case is only the second naturally inverting appendix to be removed endoscopically, and it was complicated 18 h later by local peritonitis which was heralded by acute right lower quadrant pain. Laparotomy revealed a cleanly transected base of appendix and cecal adhesions representing previous chronic inflammatory disease. Endoscopists should consider this diagnosis in all cases of mass lesions of the caput cecum. It is imperative to retrieve such lesions if polypectomy is performed, as the macroscopic diagnosis is then evident. Once the diagnosis is established, immediate surgery is advised rather than watchful waiting.

Appendix↗

Participation of follicle associated epithelium (fae), macrophages, and plasma cells in the function of appendix.

Rabbit appendix was studied by correlated scanning and transmission electron microscopy and light microscopy, taking advantage of luminal bacteria as naturally occurring markers for following antigen uptake. The three-dimensional relationship of lymphoid follicles to other structures was revealed clearly. The smooth luminal surface of the appendix is interrupted by stomata each leading to a recessed interval between the dome epithelium covering the apical pole of each follicle and the goblet cell-rich epithelium forming a cupola on the opposing surface. Bacteria abound in this recess. They are taken up by follicle associated epithelial (FAE) cells which comprise part of the dome epithelium. Intraepithelial macrophages phagocytize the bacteria. Bacteria-laden macrophages are numerous in the dome area of the follicle and in the germinal center. Large lymphatic sinuses surrounding the follicles are well visualized following stimulation of fluid movement. Plasma cells are located within the dome epithelial layer and immediately beneath it. Plasma cells may be concentrated along the base of epithelial cells, with the absence of a basal lamina indicating an absence of the molecular selection which it would normally provide. The appendix, like Peyer's patches, takes up antigens, processes them, and gives evidence of reaction to them locally, with the secretions from plasma cells possibly modulating antigen entry.

Animals↗

Lectin-binding sites in the epithelium of normal human appendix vermiformis and in acute appendicitis.

By using histochemical methods, the binding pattern of various lectins in the epithelium of normal human appendix vermiformis was assessed. In addition to plant and invertebrate sugar receptors with nominal monosaccharide specificity for alpha-L-Fuc (UEA-I), alpha-D-Man and alpha-D-Gluc (Con A), alpha-D-GalNAc (DBA), D-GalNAc (SBA, HPA) beta-D-Gal (RCA-I) and D-Gal (VAA), a mammalian beta-galactoside-specific lectin (MW, 14 kDa) was included in the applied panel. The apical surface of enterocytes presented binding sites for RCA-I on all cells, binding sites of UEA-I, DBA, SBA, HPA and VAA heterogeneously and no binding sites of Con A and 14 kDa. Binding sites of DBA, SBA, HPA, VAA and RCA-I within enterocytes were located primarily focally in a supranuclear position, whereas Con A and 14 kDa bound to the cytoplasm both in apical and basal cell parts. In the follicle-associated epithelium more enterocytes expressed SBA- and VAA-binding sites than in the crypt epithelium. No differences between the lectin-binding pattern of M-cells and enterocytes were found in the follicle-associated epithelium. Intraepithelial macrophages were heterogeneously positive for the full panel of applied lectins. In contrast, intraepithelial lymphatic cells expressed binding sites only for RCA-I and less prominently for Con A, VAA and 14 kDa. Goblet cell mucus contained lectin-binding sites in a heterogeneous manner: binding sites for Con A were not detected in goblet cells for DBA, SBA, VAA and 14 kDa in less than 20%, for UEA-I in 20-40%, for HPA in 40-60% and for RCA-I in 60-100% of the goblet cells. Secreted mucus differed in its lectin-binding capacity from intracellular goblet cell mucus selectively by an increase of UEA-I, SBA- and RCA-I-binding sites and a lack of 14 kDa-binding sites. Comparative study of lectin binding to goblet cell mucin in another region of the large intestine, namely the rectosigmoid, demonstrated that DBA, SBA and 14 kDa bound mainly to the distal colon, while UEA-I and VAA labelling was selectively found in appendiceal goblet cell mucin. Comparing the lectin-binding pattern in normal appendix epithelium and in appendicitis, the percentage of goblet cells expressing DBA- and SBA-binding sites in mucus globules was found to be about 4 times higher in appendicitis than in normal appendix.(ABSTRACT TRUNCATED AT 400 WORDS)

Acute Disease↗

Case of vesico-appendiceal fistula secondary to mucinous adenocarcinoma of the appendix.

We present a rare case of vesico-appendiceal fistula secondary to mucinous adenocarcinoma of the appendix. Transurethral biopsy of the bladder revealed a mucinous adenocarcinoma of probable colonic origin. Adenocarcinoma of the appendix that directly invaded the bladder was diagnosed preoperatively by air-contrast barium enema, colonoscopy and magnetic resonance imaging. When one encounters a case of adenocarcinoma of the bladder suspected to be of colonic origin, one should examine the colon and rectum as well as the appendix and cecum.

Adenocarcinoma, Mucinous↗

[Idiopathic granulomatous appendicitis or Crohn's disease confined to the appendix?].

Crohn's disease limited to the appendix is uncommon. When Crohn's disease affects the appendix it typically has a longer clinical course than most cases of acute appendicitis. The diagnosis is histological. Appendiceal Crohn's disease has a benign course after surgery, and that's why some authors believe that it could be a different entity which should be better addressed to as "Idiopathic Granulomatosus Appendicitis". We present three new cases of Crohn's disease limited to the appendix.

Adolescent↗

[Diverticular disease of the appendix].

The incidence of appendiceal diverticulosis in pathologic specimens is 0.004-2.1%. Diverticular disease of the appendix is classified as congenital (true) or acquired (false). The clinical presentation differs from that of acute appendicitis. The average age is older, the pain is often intermittent, and while localized in the right lower abdominal quadrant, is of longer duration. No further treatment besides appendectomy is needed. Since a high rate of perforations, peritonitis and lower gastrointestinal bleeding have been reported as complications, it is recommended that in those with an incidental finding of diverticula of the appendix during surgery, that appendectomy be performed. It is not recommended to perform prophylactic appendectomy when diverticula of the appendix are found on barium enema.

Appendectomy↗

[Ureteral replacement with appendix].

OBJECTIVE: The scant references in the literature on the use of the appendix in ureteral substitution prompted us to describe the present case in whom this technique was utilized. METHODS: The surgical technique of appendiceal interposition to repair a defect approximately 10 cm long in the right ureter is described. Following excision of a mass arising from the adnexa that entrapped the ureter at the level of the pelvis, the defect was repaired with the appendix. RESULTS: At two years follow-up, the patient is well and right excretory system function is normal. CONCLUSION: Ureteral repair with the appendix is simple and easy to perform. However, the indications for appendiceal interposition are more limited than those of the classical surgical techniques.

Appendix↗

Continent ileocecal diversion with an unaltered in situ appendix conduit.

PURPOSE: We performed continent urinary diversion using an unaltered, in situ appendix to decrease the risk of appendicocolic manipulation. MATERIALS AND METHODS: Since September 1994, 19 patients a mean of 46.5 years old underwent continent urinary diversion with an ileocecal segment and an unaltered, in situ appendiceal conduit. In 1 case of a permanent colostomy we performed simple transposition of the appendix on the ileal pouch as a conduit, which to our knowledge is the first reported case. RESULTS: During the 4 to 24-month followup (mean 12) 17 patients were continent day and night, defined as being completely dry for 3 to 5 hours. Two patients were occasionally incontinent at night. One patient with a history of multiple operations who was completely incontinent achieved complete continence with endoscopic polytetrafluoroethylene (Teflon) injection at the appendicocecal junction. CONCLUSIONS: This unaltered in situ appendix technique is timesaving, safe, effective and comparable with other methods that provide urinary continence.

Adolescent↗

Complement receptor lymphocytes in the rabbit I. an SIg-negative subpopulation in the appendix.

Complement receptor lymphocytes (CRL) were detected in various rabbit lymphoid tissues by the ability of these CRL to form rosettes with sheep red blood cells coated sequentially with rabbit antiserum directed against sheep red blood cell stroma and horse serum as a nonhemolytic source of complement (EAC). The rosette assay was shown to be specific for complement receptor (CR) activity and the EAC capable of detecting both C3b and C3d specific receptors. With lymphocyte preparations containing less than 5% phagocytic cells, the average per cent CRL in the various tissues studied was as follows: thymus 1%, popliteal lymph node 18%, spleen 30%, appendix 35%, and peripheral blood 45%. Double assays in which the lymphocytes were prestained with an FITC-labeled Fab fragment of a goat anti-rabbit Fab antibody before rosetting indicated that CRL were a subpopulation of surface immunoglobulin (SIg)-bearing lymphocytes in popliteal lymph node, spleen, and peripheral blood. In the appendix, however, in addition to finding SIg+ CR+ and SIg+ CR- populations, an SIg- CR+ population was consistently found. Double assays employing FITC-labeled goat antibodies specific for mu, alpha, and gamma determinants were also performed to determine if there was any relationship between the class of Ig displayed and presence of CR. It appeared that an approximately equivalent percentage of both IgM- and IgG-bearing cells also displayed CR. Experiments in which appendix cells were treated with Pronase to remove SIg and CR and the cells cultured in vitro to allow regeneration of surface markers confirmed the existence of SIg+CR+, SIg+CR-, and SIg-CR+ lymphocyte subpopulations. Whether the SIg-CR+, population represents a developing B cell population which will eventually also express SIg or whether it belongs to the T or "null" cell populations is unclear at present.

Animals↗

Detection of pinpoint tenderness on the appendix under ultrasonography is useful to confirm acute appendicitis.

HYPOTHESIS: Ultrasonography can be efficiently performed using new criteria for the diagnosis of acute appendicitis. DESIGN: Prospective trial. PATIENTS: Eighty-nine patients admitted to the hospital with suspected appendicitis between March 1998 and November 2000. INTERVENTION: At hospital admission, a staff surgeon evaluated each patient and determined whether the patient had appendicitis requiring immediate surgery or another disease. Patients then underwent ultrasonography. A sonographic transducer was placed on the area of maximal tenderness. When the pathological manifestation was depicted, the examiner slipped a fingertip between the transducer and the patient's skin and then pressed the area of depicted pathological manifestation to find pinpoint tenderness. When maximal pinpoint tenderness was noted on the appendix or on pathological manifestations contiguous to the appendix, we diagnosed the condition as appendicitis. MAIN OUTCOME MEASURES: Sensitivity, specificity, positive and negative predictive values, and overall accuracy. RESULTS: The diagnosis of appendicitis by this criteria had a sensitivity of 86.7%, a specificity of 89.7%, a positive predictive value of 94.5%, a negative predictive value of 76.5%, and overall accuracy of 87.6%. All 50 patients with pinpoint tenderness noted on the appendix had appendicitis. The surgeon's initial clinical impression had a sensitivity of 83.3%, a specificity of 44.8%, a positive predictive value of 75.8%, a negative predictive value of 56.5%, and overall accuracy of 70.8%. CONCLUSIONS: The efficacy of ultrasonography using the simple criteria was superior to that of the surgeon's initial clinical impression (P<.001). Our ultrasonographic criteria for the diagnosis of appendicitis are simple to use and efficient.

Acute Disease↗

Asymptomatic primary mucinous cystadenocarcinoma of the appendix with a large abdominal mass: report of a case.

A case of cystadenocarcinoma of the appendix with a large cystic lesion is reported. A 49-year-old man undergoing a routine ultrasonic scan was incidentally found to have an abdominal mass measuring some 30 cm in size. The clinical presentation was asymptomatic, and the patient underwent a laparotomy without ascertaining a diagnosis preoperatively. The lesion, which derived from the appendix, was removed and was found to be cystic and contained huge amounts of mucin. The histological findings revealed a well-differentiated cystadenocarcinoma of the appendix, and immunohistochemical staining of the epithelium and mucinous implants in the mass demonstrated a positive reaction for carcinogenic antigens, including carcinoembryonic antigen and carbohydrate antigen.

Abdominal Neoplasms↗

Management and prognosis of adenocarcinoma of the appendix.

PURPOSE: Adenocarcinoma of the appendix is a rare neoplasm, and controversies persist regarding management. The purpose of this study was to identify prognostic factors and define management strategies for patients with adenocarcinoma of the appendix. METHODS: A retrospective case series was conducted at three medical school teaching hospitals over a 20-year period from 1972 to 1992. Overall survival was determined by the actuarial life table method. Comparisons of prognostic factors were made using exact nonparametric log-rank tests. RESULTS: Thirteen patients were diagnosed during the study period. Median age was 62 years. There were five males and eight females. The disease was not suspected in any patient preoperatively. Seventy-seven percent of patients had metastatic disease at presentation. Second primary malignancies were found in 15 percent of patients. Thirty-eight percent of female patients had synchronous ovarian lesions. Median survival was 22 months, with an estimated five-year survival of 43 percent (95 percent confidence interval, 22-84 percent). Patients with colonic histology had significantly worse survival than patients with mucinous histology (P = 0.0093). Patients with carcinomatosis had a significantly worse survival than noncarcinomatosis patients (P = 0.0078). Patients who underwent right hemicolectomy had a better prognosis for survival than appendectomy patients, but the difference was not statistically significant. CONCLUSIONS: Carcinoma of the appendix is very difficult to diagnose preoperatively, and most patients are not identified until disease is advanced. Good prognostic factors include mucinous histology and the absence of carcinomatosis. Right hemicolectomy appears to be a reasonable option, although its superiority to appendectomy alone has not been definitively proven. High frequency of ovarian metastases in women suggests a role for bilateral oophorectomy. In addition, a complete work-up of the patient for a synchronous malignancy, especially in the gastrointestinal tract, should be considered.

Adenocarcinoma↗

Granular cell tumour of the appendix in a patient irradiated for a rectal carcinoma.

We report on a 47-year-old man with a granular cell tumour of the appendix, discovered incidentally during surgery for a rectal adenocarcinoma that had been irradiated preoperatively. A detailed immunocytochemical analysis revealed positivity for S-100 and neuron-specific enolase (NSE). Electron microscopically, the cytoplasm of the tumour cells contained numerous pleomorphic lysosomes. In the appendix tissue adjacent to the tumour a neuroma and the histological features of radiation injury were present. Our findings suggest that this granular cell tumour may have originated from a pre-existing appendix neuroma which underwent granular degeneration, possibly as a result of radiation.

Appendiceal Neoplasms↗

Metastatic carcinoid tumor of the appendix. Report of a case and review of the literature.

A case of regional metastatic carcinoid of the appendix is presented and the literature reviewed for indications for right colectomy. Five cases of lymph-node metastasis from primary appendiceal carcinoids less than 2 cm in diameter have been reported. There is no reported case of systemic metastasis occurring after appendectomy for a carcinoid with a diameter of less than 2 cm. Perineural involvement, lymphatic invasion, mesoappendiceal invasion, histologic appearance, and location of the tumor in the appendix seem to be unreliable predictors of clinically significant regional node involvement. It is concluded that a right colectomy is indicated only in patients with carcinoid tumors of the appendix 2 cm or more in diameter, or with residual tumor at the margin of resection.

Adult↗

Retrospective evaluation of carcinoid tumors of the appendix in children.

Carcinoids of the appendix are rare in children and are usually diagnosed incidentally on histologic investigation following appendectomy for appendicitis. To investigate the significance of the diagnosis of appendiceal carcinoid in children, we conducted a retrospective study of the treatment and follow-up of 36 children with histologically confirmed carcinoid tumors of the appendix. Between 1970 and 2000 a total of 36 patients (25 girls, 11 boys) were diagnosed with appendiceal carcinoid. The median age of the patients at diagnosis was 12.3 years (range 6-16 years). The indication for appendectomy was acute lower right quadrant pain in 27 cases and chronic right lower quadrant pain in 9 patients. In 27 specimens the tumor was localized at the apex, in 7 at the midportion, and in 2 at the base of the appendix. The median tumor diameter was 6 mm (range 3-17 mm). Concomitant severe appendicitis was diagnosed in 14 patients 2 with a perforated appendicitis. In only one tumor were mucin-producing cells detectable. After a median follow-up of 10 years (range 2 months to 30 years) all patients were tumor-free. None of the patients had a synchronous or metachronous noncarcinoid malignant tumor. Appendiceal carcinoids are usually asymptomatic, and the indication for surgical intervention is acute or chronic abdominal pains in the right lower quadrant. For most patients the prognosis is excellent after appendectomy. As in adults, appendectomy is the appropriate treatment.

Adolescent↗

Carcinoid tumor of the appendix in the first two decades of life.

Carcinoid tumor of the appendix is the most common neoplasm of the gastrointestinal tract in childhood and adolescence. Sufficient long-term follow-up data after surgical treatment are not currently available for patients diagnosed during the first two decades of life. From 1936 to 1988, 23 patients were observed at this institution with histologically confirmed carcinoid tumors involving the vermiform appendix. In contrast to the adult experience, in which the tumor is most commonly encountered as the result of an incidental appendectomy, 18 of these patients presented with signs and symptoms of an acute abdomen directing the surgeon to the appendix. In the other five cases, surgery was performed for other reasons. Median age at presentation was 13.0 years (range, 6 to 20 years). Fourteen patients were female, nine were male. Simple appendectomy was the initial procedure for all patients. Tumor size ranged from "microscopic" to 2.5 cm in largest dimension. Three patients subsequently underwent right hemicolectomy, and one patient had removal of a residual appendiceal stump, but no residual or metastatic tumor tissue was found in any of the resected specimens. Nineteen patients underwent simple appendectomy alone. Eighteen available specimens were reviewed at the time of this study for confirmation of histology and degree of invasion. The tumor invaded to the serosa in nine of 23 (39%). The mesoappendix or periappendiceal fat was involved in seven of 23 (30%). Vessel invasion was not noted in any specimen. Our median follow-up time was very long, being 26 years (range, 9 months to 51 years). No patient has had evidence of recurrent or metastatic disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Mucinous tumors of the vermiform appendix and ovary, and pseudomyxoma peritonei: histogenetic implications of cytokeratin 7 expression.

Cytokeratin 7 (CK-7) has been shown to be uncommonly expressed in colonic epithelial tumors, as opposed to ovarian epithelial tumors, which are always CK-7 positive. The authors investigated the expression of CK-7 in 17 appendiceal cystadenomas and carcinomas, 20 mucinous borderline tumors of the ovary, 10 cases of simultaneous mucinous tumors of the appendix and ovary, three so-called high-stage mucinous borderline tumors of the ovary, and three cases of pseudomyxoma peritonei (PP) of unknown origin. Nine appendiceal cystadenomas were CK-7 negative; two of these were associated with PP, and the peritoneal lesions were negative as well. Three cystadenomas were CK-7 positive. Three appendiceal carcinomas were CK-7 negative, and in one case the metastases were also negative. Two carcinomas were CK-7 positive. All 20 ovarian borderline tumors were CK-7 positive. Six cases of simultaneous mucinous tumors of the ovary and appendix were CK-7 negative, as were their peritoneal mucinous deposits. Four cases showed a positive reaction in both appendiceal and ovarian sites. Two of three so-called high-stage ovarian borderline tumors were CK-7 negative. All three cases of PP of unknown origin were CK-7 negative. In conclusion, appendiceal cystadenomas are often CK-7 negative, whereas ovarian mucinous borderline tumors are always CK-7 positive. The concordant staining pattern for CK-7 of simultaneous mucinous tumors involving the appendix and ovary (60% of which were CK-7 negative) supports an appendiceal origin for these tumors. Our results also support an appendiceal (or colonic) source for any CK-7-negative mucinous tumor involving the ovary or the peritoneum. Furthermore, our findings are in agreement with the assumption that mucinous borderline-like tumors in the ovary associated with PP are not ovarian in origin but are often, if not always, metastatic from an appendiceal (or other) mucinous tumor.

Adult↗

Müllerian-type epithelial tumor arising within a torsed appendix testis.

Because it is a remnant of the müllerian duct system, the appendix testis contains müllerian epithelium that theoretically may produce epithelial tumors similar to those that occur in the female genital tract. Few reports of tumors of müllerian origin arising in the testis exist, and rarely are neoplasms arising from the appendix testis identified. We present a case of a serous cystic neoplasm of low malignant potential derived from müllerian-type epithelium that was located in the torsed appendix testis of a young, otherwise healthy, boy.

Adolescent↗