Pathology of tropical appendicitis

Acute appendicitis secondary to Entamoeba histolytica infestation

Acute appendicitis secondary to amoebic infestation is a rare possibility, especially in endemic areas. If left untreated, significant postoperative morbidity and mortality can result from the spread of amoebic trophozoites and subsequent tissue reaction. Histopathological examination of the resected appendix with demonstration of invasion by the parasite is mandatory for establishing a diagnosis. Careful examination of the specimen is thus of paramount importance.

Acute amebic appendicitis in early pregnancy

Parasitic infections of the intestine are a major health problem, which is found more prevalent in developing countries such as India. They are one of the important causes of morbidity and mortality among people all over the world. Acute amoebic appendicitis is a rare entity. We came across a case of acute appendicitis in a young pregnant woman, which revealed colonies of Entamoeba histolytica trophozoites in the mucosal epithelium and submucosal layer of the appendix with marked evidence of acute appendicitis. This report highlights acute appendicitis of amoebic origin and emphasises the importance of thorough examination of the appendix at various levels during histopathology and about the combined treatment of appendicectomy combined with antimicrobials as the treatment of choice. Appendicectomy removes the focus of infection, and antimicrobials reduce the incidence of septic complications.

Parasites in surgically removed appendices as a neglected public health concern: a systematic review and meta-analysis

The role of various parasitic infections in the occurrence of appendicitis is illustrated through cases recorded all over the world. The purpose of the current study was to estimate the global prevalence of parasite infestation (other than E. vermicularis) in appendectomy specimens.In the setting of the PRISMA guidelines, multiple databases (Science Direct, Scopus, Web of Science, PubMed, and Google Scholar) were explored in articles published until 28 September 2020. Totally, 62 studies (106 datasets) with 77, 619 participants were included in the analysis.The pooled prevalence of parasites in appendectomy samples was as follows; 0.012% (95% CI; 0.004-0.025) for Ascaris lumbricoides, 0.004% (95% CI; 0.001-0.009) for Trichuris trichiura, 0.025% (95% CI; 0.007-0.052) for Schistosoma mansoni, 0.002% (95% CI; 0.001-0.005) for Taenia spp., 0.061% (95% CI; 0.020-0.122) for Entamoeba histolytica and 0.034% (95% CI; 0.018-0.056) for Giardia lamblia.Our results demonstrated that the risk of appendicitis may increase in the presence of helminth and protozoan infections. As such, the most cases of parasites in appendectomy specimens were reported in developing countries. Regular screening plans for diagnosis, treatment and prevention are needed for prevention of parasitic infection as well as parasitic associated appendicitis, especially in endemic regions of the world.

Acute eosinophilic appendicitis caused by Taenia saginata: A case report

INTRODUCTION

The role of parasites in the pathogenesis of appendicitis has been debated for a long time. To date, several gastrointestinal parasites have been reported as the causes of appendicitis in humans. Taenia infestation of the appendix is uncommon and few cases have been reported in the literature.

PRESENTATION OF CASE

We reported a case of acute eosinophilic appendicitis (AEA) in a 42-year-old woman caused by T. saginata in northern Iran. The patient was admitted to the emergency department with a 2-day history of acute abdominal pain in her lower right quadrant. Abdominal ultrasonography showed intra-abdominal bleeding and endometrium cysts. Routine hematological tests showed increases in white blood cell (WBC) count of 19.8 × 103 per mcL with 3% eosinophilia. During abdominal laparotomy, peritoneal fluid was bulked with abdominal bleeding due to rupture of the uterine cyst. After investigation of inflammation in the appendix region, patient underwent appendectomy. Histopathological findings showed acute inflammation with eosinophils and a large number of round eggs with flattened segments of the genus Taenia. It is impossible to distinguish between T. saginata and T. solium based solely on egg morphology in the specimens. Therefore, based on history of the patient, which included no consumption of pork, the species was identified as T. saginata. At the three months follow-up, the patient was in good health.

CONCLUSION

In the current study, a case of AEA by T. saginata was reported. However, this was not the first case of acute appendicitis by T. saginata. Further studies are necessary to show roles of parasites in pathogenesis of AEA.

Appendicular tuberculosis: a less encountered clinical entity

A 21-year-old female patient presented with vague lower abdominal pain associated with nausea since 2 days. On examination, she was tender in the right iliac fossa. Based on clinical presentation and radiological test finding, she was diagnosed as appendicitis and was subjected for diagnostic laparoscopy and appendectomy. Histopathology proved it to be a tubercular appendix, which is a rarely encountered entity. However, in a country like India, tuberculosis (TB) is highly prevalent; however, TB of appendix is rare and less known.

Primary tuberculosis of the appendix: A common disease with rare location - a rare case report from rural India

Tubercular appendicitis is the appendicular infection with tubercular bacillus, which develops as an extension of ileocecal infection. Tuberculosis is either primary or secondary. Primary tuberculosis of the appendix is uncommon. Diagnosis is made by histopathological examination of the resected appendix. We report a rare case of tubercular appendicitis diagnosed on histopathology. Primary Tuberculosis of the appendix is a clinical rarity. Hence, it is being reported. The case report in this study emphasizes the importance of submitting all appendectomy specimens for histopathological examination and the occurrence of primary tuberculosis at a rare site, such as the appendix.

The Prevalence of Intestinal Parasite Infection in El Behara Schoolchildren

This study was conducted to evaluate the prevalence of intestinal parasite in schoolchildren in Damanhur, Egypt and some of its villages. The pathogenic enteric protozoa have been progressively involved in bargaining the soundness of a great many individuals, for the most part in creating nations. Mediations are being set up to control the dreariness and mortality because of these protozoan contaminations. A portion of these mediations target school going kids with regards to class based wellbeing intercession. The present examination concentrated on exploring the commonness of intestinal protozoan contaminations among younger students chose networks comprising of urban, urban-poor and per urban settlements in the Damanhour and a few towns. In the present work Giardia lamblia was the second usually identified protozoan with a diseases rate 10.4% among the analyzed cases. In the present examination generally speaking level of parasitic contaminations among the kids was 57.3%. It's viewed as Enterobius vermicularis was the most usually identified protozoan as it spoke to 4.1% of the parasitic diseases in the considered cases pursued by Ascaris lumbricoides; 1.4% and Giardia lamblia contaminations as they spoke to 0.6%; separately. The protozoa like Giardia and Cryptosporidium are regularly present in surface waters and cause episodes in this manner legitimately affecting human wellbeing.

Parasitic infestation in appendicitis. A retrospective analysis of 660 patients and brief literature review

OBJECTIVES

To investigate the incidence of parasitic infestations and inflammation accompanying parasitosis in a series of appendectomy cases.  Methods: Six-hundred-sixty  patients who had undergone appendectomy in Bingöl State Hospital, Bingol, Turkey with the preliminary diagnosis of appendicitis between January 2012 and February 2015 were included in this retrospective study. They were retrospectively evaluated in terms of age, gender and pathological findings. Cases diagnosed with parasitic infestations were re-evaluated histopathologically for inflammatory response.  Results: The mean age was 19.6 years, and the male/female ratio was 1.8. When evaluated in terms of histopathological diagnoses, 573 (86.8%) were diagnosed as acute appendicitis, and parasitic infestation was identified in 12 (1.8%). Among cases with parasitic infestation, Enterobius vermicularis was identified in 9 (75%) and Taenia in 3 (25%) cases. Of cases with Enterobius vermicularis, 4 (44.4%) had lymphoid hyperplasia, 1 (11.1%) had normal-structured appendix vermiformis, and 4 (44.4%) had findings of acute appendicitis. All cases with taeniasis had an inflammatory response: acute appendicitis was identified in 2 (66%) and acute gangrenous appendicitis in 1 (33%) of them.  Conclusion: Parasitic infestations are among the probable causes in appendicitis etiology and should be kept in mind during differential diagnosis. However, whether every parasitic infestation leads to appendiceal inflammatory response is controversial.

Unexpected Appendiceal Pathologies and Their Changes With the Expanding Use of Preoperative Imaging Studies

Purpose

The preoperative diagnosis of acute appendicitis is often challenging. Sometimes, pathologic results of the appendix embarrass or confuse surgeons. Therefore, more and more imaging studies are being performed to increase the accuracy of appendicitis diagnoses preoperatively. However, data on the effect of this increase in preoperative imaging studies on diagnostic accuracy are limited. We performed this study to explore unexpected appendiceal pathologies and to delineate the role of preoperative imaging studies in the diagnosis of acute appendicitis.

Methods

The medical records of 4,673 patients who underwent an appendectomy for assumed appendicitis between 1997 and 2012 were reviewed retrospectively. Pathological results and preoperative imaging studies were surveyed, and the frequencies of pathological results and preoperative imaging studies were investigated.

Results

The overall rate of pathology compatible with acute appendicitis was 84.4%. Unexpected pathological findings, such as normal histology, specific inflammations other than acute appendicitis, neoplastic lesions, and other pathologies, comprised 9.6%, 3.3%, 1.2%, and 1.5%, respectively. The rate of unexpected pathological results was significantly reduced because of the increase in preoperative imaging studies. The decrease in normal appendices contributed the most to the reduction while other unexpected pathologies did not change significantly despite the increased use of imaging studies. This decrease in normal appendices was significant in both male and female patients under the age of 60 years, but the differences in females were more prominent.

Conclusion

Unexpected appendiceal pathologies comprised 15.6% of the cases. Preoperative imaging studies reduced them by decreasing the negative appendectomy rate of patients with normal appendices.

Tuberculous Appendicitis in India

Tuberculous appendicitis (TBA) is a rare condition. The present study has been conducted to study its prevalence and presentation. This retrospective study was performed in the Department of Surgery, NSCB Government Medical College, Jabalpur, MP, India, in 870 consecutive appendectomies performed between January 1991 and December 2000. Of 870 consecutive appendicular specimens, 10 cases of primary (1.1%) and 16 of secondary TBA (1.8%) were encountered. Results of all pre-operative investigations were non-specific and the diagnosis was made only after histopathology. The prevalence of TBA in this study was 2.9%. Although it is a rare condition, its possibility should be kept inmind by clinicians as well as pathologists. All surgically removed appendix specimens should be histopathologically examined, whether or not the specimens are macroscopically normal. Given anti-tubercular treatment in addition to appendectomy, patients recover without complications.

Co-infection with Enterobius vermicularis and Taenia saginata mimicking acute appendicitis

In this report, we describe an unusual case of verminous appendicitis due to Enterobius vermicularis and Taenia saginata in a 29-year-old woman from Iran. The histopathological examinations and parasitological descriptions of both worms found in the appendix lumen are discussed. The removed appendix exhibited the macroscopic and microscopic features of acute appendicitis. Antihelminthic therapy was initiated with single doses of praziquantel for the taeniasis and mebendazole for the enterobiasis, and the patient was discharged.

An Uncommon Case of Chronic Tubercular Appendicitis

Tuberculosis (TB) is a common disease that ranks as the second leading cause of death from an infectious disease worldwide, after the human immunodeficiency virus (HIV). However, primary TB of the appendix is rare and may or may not be associated with specific clinical features. Thus, diagnosis is made only after histopathological examination. It suggests that all surgically removed appendices should be subjected to histopathological examination. This reported case is an uncommon case of chronic tubercular appendicitis.

A rare cause of acute abdomen in adults: Parasitic infection-related acute appendicitis

Ascaris lumbricoides is a common parasitic disease all over the world, especially in less developed countries. Acute appendicitis related to parasitic infection is a rare condition. Parasitic infections should be kept in mind in patients who are admitted to the emergency department with acute abdomen, especially in endemic areas.

Histopathological findings in appendectomy specimens: a study of 24,697 cases

PURPOSE

Appendicitis is by far the commonest major emergency general surgical operation. Histopathological examination of the appendix is routinely performed.

METHODS

This study is a retrospective analysis of 24,697 appendectomies performed from January 2003 to December 2011. Pathological reports were analyzed for the following parameters: age, gender, and pathological diagnosis.

RESULTS

Appendectomy specimens represent 17 % of all pathological reports. Acute appendicitis was present in 19,637 (79.5 %) patients. The perforation rate was 6.3 % and was significantly higher in adult patients. The negative appendectomy rate was 15 % and was significantly higher in female and adult patients. The incidence of negative appendectomies had clearly decreased over the 9-year period distribution. Incidental unexpected pathological diagnoses were noted in 226 (0.9 %) appendectomy specimens. Neoplastic lesions were present in 171 cases (0.7 %); they include carcinoid, adenocarcinoma, and mucinous neoplasms.

CONCLUSIONS

Routine pathological examination of appendectomy specimens is expensive. With advances in technology and imaging modalities, the diagnosis of acute appendicitis has improved, with a subsequent significant reduction in negative appendectomy. There are still a number of unusual diagnoses found in appendicectomy specimens supporting the continued use of routine histology.

Faecolith examination for spectrum of parasitic association in appendicitis

BACKGROUND

The appendix is a vestigial organ which is infiltrated by faecal material, microbes and parasites. The most important aetio-pathology of appendicitis is obstruction of its lumen, by a faecolith. This results from accumulation and inspissation of faecal matter around vegetable fibres. The cause for appendicitis is numerous and one among them is parasitic infestation.

AIMS

To analyze the faecolith present in the appendectomy specimen for parasites and to compare the results in fresh and preserved specimens.

MATERIALS AND METHODS

Patients with acute/chronic appendicitis were subjected for surgery and the appendectomy specimens were collected in saline and formalin suspensions, for preservation purposes. The lumen was washed with normal saline and contents were collected and wet mount preparations were examined under low and high power microscopy.

RESULTS

Among 100 specimens 48 faecolith analyses proved to be positive for parasitic association, giving 48% positivity, which is quite high. The commonest isolate was followed by mixed infection. In our study we observed that saline preparations were easy for handling and we were also able to demonstrate the undistorted morphology of parasite better than formalin preserved specimens.

CONCLUSION

This study reveals the importance of analyzing the appendectomy specimen for understanding the etiopathogenisis of appendicitis in spite of having a negative stool microscopy. A post surgical analysis of appendectomy specimen may surprise you with different etiological agents as confirmed by our study.

Unusual findings in appendectomy specimens of adults: retrospective analyses of 1466 patients and a review of literature

BACKGROUND

Diseases and tumors of the appendix vermiformis are very rare, except acute appendicitis.

OBJECTIVES

This retrospective study was conducted to document the unusual findings in appendectomy specimens.

PATIENTS AND METHODS

Data of 1466 adult patients were gathered retrospectively. Appendectomy was performed in 1169 and in 297 patients following a diagnosis of acute appendicitis and during other abdominal operations, respectively. The data of 57 (3.88 %) patients who were pathologically reported to have unusual appendix findings were retrospectively collected. The records were analyzed according to patients' age, gender, clinical presentations, operative reports, pathological reports and follow up.

RESULTS

Unusual pathologic examination findings were detected in the appendectomy specimens of 57 patients with a mean age of 48.34 ± 19. Twenty-nine patients (50.8 %) were male and 28 (49.2 %) were female. Normal appendix tissues were observed in specimens of 26 (45.6 %) patients and inflamed appendix in 31 (54.3 %). The most common unusual finding was parasitic diseases of the intestine. Pathological diagnosis of malignancy and benign features were reported in specimens of 14 and 43 patients, respectively. Macroscopic evaluation of appendectomy specimens during surgery might result in negligence of the presence of unusual pathology.

CONCLUSIONS

Even if the macroscopic appearance of the specimen is normal or acute appendicitis, we suggest routine histopathological examination.

Primary tuberculosis of the appendix: a rare cause of a common disease

Tuberculosis is still a common infection in India. Although the ileocecal region is the most affected part in intestinal tuberculosis, acute tuberculous appendicitis is quite a rare entity. Our case report highlights a rare presentation of tuberculosis and a brief review of literature.

Amebic acute appendicitis: systematic review of 174 cases

BACKGROUND

This study aimed to determine the clinical and demographic features of acute amebic appendicitis by reviewing the reported cases.

METHODS

The PubMed and MEDLINE databases were searched to identify articles related to amebic appendicitis using key words. The search included all articles published between 1935 and 2012 without restricting language, journal, or country.

RESULTS

A total of 174 cases of amebic appendicitis reported in 42 articles were analyzed. The mean age of the patients was 23.5 years (range 2 months-83 years). The majority of patients were male (74.0 %), and the majority of cases were reported from countries with high/moderate risk for amebiasis (76.5 %). A history of traveling to a high/moderate-risk country was cited in 64.0 % of the overall cases. The interval between travel and onset of clinical symptoms ranged from months to years. History of or coexisting dysenteric diarrhea was present in only 7.0 and 14.0 % of overall cases, respectively. A preoperative diagnosis of amebiasis was cited for only five cases (3.0 %). Complicated appendicitis was present in 30.7 % of cases, some of which required colon resection. Severe postoperative intraabdominal complications (e.g., liver abscess, abdominal sepsis, gastrointestinal fistula, hemorrhage) occurred in 19.4 % of surgery-treated patients. The overall mortality rate was 3.2 %.

CONCLUSION

Appendectomy specimens should be routinely sent for histopathologic examination. In the case of suspected amebic acute appendicitis, extra precautions-early appendectomy, metronidazole for antibiotic prophylaxis, wet-preparation examination, obtaining a timely pathology result, increasing the awareness of uncommon complications of appendectomy-can hasten appropriate therapeutic intervention and improve outcome.

Parasitic infestation in pediatric and adolescent appendicitis: a local experience

OBJECTIVE

The relationship between parasites and pediatric appendicitis is a highly debatable issue. This study aims to investigate the role of parasitic infestation in the etiology of acute pediatric appendicitis.

METHODS

A retrospective study including 1600 pediatric and adolescent patients who had undergone surgical therapy for a diagnosis of acute appendicitis over a period of ten years from Jan 2001 to Dec 2010. Demographic data were retrieved including the patient's age, sex, clinical data, clinical presentations, laboratory investigations, operative data and pathological findings to identify the presence and type of parasites. Patients were divided into two groups according to the presence or absence of parasites in the appendix lumen. In group I (n: 88), parasitic infestation was observed, whereas in group II (n: 1502), no parasitic infestation was present.

RESULTS

Parasites were present in 5.5% (88 patients), and of those 88 parasitic infestations, 45 (51.1%) were Enterobaisis, 8 (9.1%) were Schistosomiasis, 23 (26.1%) were Ascariasis, 7 (8%) Trichuriasis, and 5 (5.7%) were Teania Saginata. The percentage of patients with suppurative, gangrenous or perforated appendicitis was similar in both groups with no statistical significance, irrespective of the presence or absence of parasitic infestation.

CONCLUSION

The low prevalence of parasites among the appendectomy specimens did not support the notion that parasites were a major cause of appendicitis in pediatric patients.

Acute Amoebic Appendicitis: Case Reports and Review of Parasitic Appendicitis

Amoebic appendicitis is very rare, occurring in about 0.5% to 2% of acute appendicitis, and usually not reported in children. We report a case of confirmed acute amoebic appendicitis complicating amoebic colitis in a 7-year-old Pakistani boy living in southern Jeddah, Saudi Arabia, and briefly review the literature on parasitic appendicitis.

A rare case of gangrenous appendicitis by eggs of Taenia species

Cysticercosis and Taeniasis continue to be a major public health burden in the developing countries like India. Humans are the only definitive hosts infected by ingestion of eggs of Taenia species. Appendicular Taeniasis is rare with few isolated case reports during the past 30 years. Here, we report the case of a 38-year-old female patient from Nepal who presented with acute pain abdomen, was operated and diagnosed as suffering from gangrenous appendicitis caused by eggs of Taenia species.

Is routine histopathological examination of appendectomy specimens useful? A systematic review of the literature

AIM

Histopathological examination of the appendix after appendectomy is routinely performed. The object of this systematic review is to determine whether routine histopathological examination of the appendix is justified.

METHOD

PubMed, EMBASE, Web of Science and the Cochrane library were searched without language restriction up to 1 October 2009. All articles that reported on the incidence of histopathologically proven aberrant appendiceal pathology were included.

RESULTS

Nineteen case series reported the incidence of a benign neoplasm [0.5%, weighted mean (WM)], malignant neoplasm (0.2%, WM) and other pathology (0-14%). Nine articles reported the sensitivity of the intra-operative findings to detect aberrant diagnoses. Parasitic infection was detected in 0-19%, endometriosis in 0% and granulomatosis in 0-11% of cases. Five articles addressed the consequences of aberrant pathology. Most patients with parasite infection, granulomatosis and malignant neoplasms underwent additional investigation or treatment, in contrast to patients with a benign neoplasm.

CONCLUSION

The incidence of unexpected findings in appendectomy specimens is low and the intra-operative diagnosis alone appears insufficient for identifying unexpected disease. The benefit of histopathology is studied inadequately. From the present available evidence, routine histopathology cannot be judged as useless.

Tuberculous appendicitis

Gastrointestinal tuberculosis is quite rare, representing only 3% of all extrapulmonary cases. Involvement of the appendix is rare, only occurring in about 1% of cases. It is usually secondary to tuberculosis elsewhere in the abdomen. A prompt diagnosis depends on a high index of suspicion as clinical signs may be nonspecific and microbiological confirmation is difficult. Histopathologic examination is often the only way to reach a diagnosis and to establish specific antibiotic therapy. In these cases, due to the absence of specific symptoms and signs, the diagnosis is delayed until after surgery.

Granulomatous diseases and granulomas of the appendix

Granulomatous appendicitis is a rare phenomenon. Idiopathic (primary) granulomatous appendicitis is very rare. It is a diagnosis by exclusion. There are many etiologies, both infectious and noninfectious, for secondary granulomatous appendicitis. Isolated appendiceal Crohn's disease (CD) is no longer an accepted explanation of idiopathic granulomatous appendicitis, but rather, it is thought to be part of more generalized gastrointestinal CD. Yersinia infection and CD constitute the main etiology of granulomatous appendicitis in the West. Infectious causes, mainly tuberculosis and parasitic infestations, are the main culprits in tropical and subtropical countries. This variation is probably a result of differences in the geographical distribution of these diseases. Recently, interval appendectomy has been suggested as an important cause of granulomatous appendicitis. The importance of interval appendectomy may vary according to the local practice of this procedure in each region. Other unusual causes may include sarcoidosis and foreign body reaction, mainly as a result of vegetable matter from feces. A review study of 3381 appendectomy specimens over a 4-year period showed only 13 cases (0.38%) of granulomatous appendicitis. Infectious and noninfectious causes were responsible for 62% and 38% of granulomatous appendicitis, respectively. Parasites alone were responsible for 38.5% of the cases. Interval appendectomy and CD each contributed 15% and 8%, respectively, of the total etiology. Granulomatous appendicitis was more common in young adult males.

Amebiasis presenting as acute appendicitis

Amebiasis presenting as acute appendicitis is extremely rare. The case of a 38-year-old Hispanic man who presented to the hospital with symptoms and signs suggestive of acute appendicitis is reported. He underwent laparoscopic appendectomy and the pathologic examination of the appendix revealed multiple trophozoites of Entamoeba histolytica. The patient was treated postoperatively with metronidazole for amebiasis, and follow-up stool studies showed no sign of residual infection. The patient has remained asymptomatic.

Acute amebic appendicitis

INTRODUCTION

Acute appendicitis of amebic origin is considered a rare cause of acute appendicitis.

METHODS

The clinical notes for 4093 patients over the age of 16 who had undergone appendectomy were reviewed. Particular attention was paid to the histopathologic results, separating out those cases where trophozoites were seen in the appendix. These cases were considered to be of amebic origin.

RESULTS

A total of 93 cases reported lesions suggestive of amebiasis (2.3%). This study analyzed 86 of these cases. Comparing the cases in this study against the cases of patients with acute appendicitis in general (excluding the cases of amebic origin), no differences were found in relation to the distribution or presentation according to sex or in the degree of inflammation of the appendix, the incidence of surgical wound infection, or general complications. By contrast, the study noted a statistically significant difference in the age at presentation: Acute appendicitis of amebic origin presents principally among those under 20 years of age and is accompanied by a higher frequency of fecal fistula (2.3%).

CONCLUSIONS

Acute appendicitis of amebic origin is not seen frequently, and in general it does not behave any differently from other cases of acute appendicitis, except in its earlier presentation and its greater incidence of fecal fistula. The condition is suspected clinically whenever a cecum of hard, "cardboard-like" consistency is discovered.

Review of the pathological results of 2660 appendicectomy specimens

PURPOSE

Appendicitis is the most commonly performed emergency abdominal surgery. The appendix can also be the site of a variety of neoplasms and unusual inflammatory conditions. A retrospective review was performed to determine the pathological diagnoses in appendicectomy specimens.

METHODS

This study is a retrospective analysis of 2660 appendicectomies performed from 1997 to 2003. The reports were analyzed for the following parameters: age-related incidence of acute appendicitis, seasonal variation in presentation, perforation rate, rate of negative and incidental appendicectomy, and the incidence of other pathologies encountered.

RESULTS

Of the 2660 appendicectomy specimens, acute appendicitis was seen in 1718 patients (64.58%), with a peak in patients in their second decade (35.09% of cases of acute appendicitis). The perforation rate was 13.9% and was significantly higher in patients aged 70 years or more (P < 0.001). The negative appendicectomy rate was 28.8%, and was significantly higher in female patients (P < 0.001) and in the 11-30 year age group (P < 0.001). Other pathologies include carcinoid (0.52%), adenocarcinoma (0.39%), and mucinous cystadenoma (0.60%).

CONCLUSIONS

The high rate of negative appendicectomy among female patients and the increased incidence of perforation in elderly patients reinforce the validity of the judicious use of laparoscopy in these populations. There are still a number of unusual histologies found in appendicectomy specimens supporting the continued use of routine histology.

Clinical manifestations of appendiceal pinworms in children: an institutional experience and a review of the literature

The association of Enterobius vermicularis infestation with acute appendicitis varies from 0.2-41.8% worldwide. Our purpose was to determine the significance of Enterobius-associated appendicitis by retrospective review of appendectomies performed during a 5-year period at a major children's hospital. The Surgical Pathology database at Children's Hospital, Columbus, Ohio, was reviewed for appendiceal specimens found to have Enterobius infestation. Corresponding patient charts were evaluated for age, gender, presenting symptoms, laboratory data, operative findings, and clinical course. Of the 1,549 appendectomies performed from January 1998 through January 2003, 21 specimens (1.4%) were found to contain Enterobius vermicularis. Fifteen of the appendectomies were performed for symptoms of acute appendicitis; the remaining six were incidental appendectomies in conjunction with other operations. The mean age was 8.9 years. Ten patients were male; 11 were female. Of the 15 symptomatic children, nine presented with fever >99.0 degrees F, and 11 had a WBC count >10,000. Intra-operative appearance of the appendix ranged from normal to perforation. Pathologic evaluation showed neutrophil or eosinophil infiltration in 15 of the 21 specimens. Enterobius infestation is an uncommon cause of acute appendicitis in children in the United States. It may be associated with acute appendicitis, "chronic appendicitis," ruptured appendicitis, or with no significant clinical symptoms.

Chemotherapy of enterobiasis (oxyuriasis)

Enterobius vermicularis (syn. Oxyurus vermicularis), also known as pinworm or seatworm, is the causative agent of human enterobiasis (oxyuriasis). The disease is more prevalent in temperate regions and is facilitated by factors such as overcrowding in schools and family groupings, as well as inadequate personal and community hygiene. Although the infection is more likely to occur in lower socioeconomic groups, enterobiasis has been reported to affect virtually every level of the general population and especially children. In the great majority of cases, enterobiasis is asymptomatic. One common symptom is intense pruritus ani that in some patients can lead to insomnia, restlessness and irritability. Scratching may cause skin irritation, and in more serious cases, eczematous dermatitis, haemorrhage or secondary bacterial infections. Ectopic migration of E. vermicularis often results in pinworm infestation of the female genital tract often causing granulomas of the uterus, ovary and the fallopian tubes and pelvic peritoneum. Anthelmintic therapies for enterobiasis are successful and include mebendazole, albendazole and pyrantel pamoate. Mass medication of affected groups reduced symptoms rapidly, progressively and in a cost-effective way.

Preoperative sonographic diagnosis of acute appendicitis caused by Ascaris lumbricoides

Acute appendicitis caused by Ascaris lumbricoides is an uncommon variant of a common disease. We describe a case in which sonography was used for preoperative diagnosis of ascaris appendicitis.

Enterobius, trichuris, capillaria, and hookworm including ancylostoma caninum

Infections by the nematodes Enterobius, Trichuris, Capillaria, and hookworm are some of the most widespread gastrointestinal infections worldwide. This article is designed not only to provide an overview of the different parasites in terms of epidemiology, clinical manifestation, and disease but also to highlight particular areas of intensive research activity that are providing new insights into both the biology of the host-parasite relationship and possible new approaches to infection management for the future.

Neoplastic lesions of the appendix

Neoplasms occur in 0.5 per cent of appendices. Ultrasonography or computed tomography is beneficial, but preoperative detection is rare. At operation, the diagnosis is considered in under half of cases. Mucocele, localized pseudomyxoma peritonei, benign tumours and most appendiceal carcinoids are cured by appendicectomy alone. Right hemicolectomy is indicated for: (1) invasive adenocarcinoma; (2) tumours close to the caecum; (3) lesions larger than 2 cm; (4) mucin production; (5) invasion of the lymphatics, serosa or mesoappendix; and (6) cellular pleomorphism with a high mitotic rate. Tumours of 1-2 cm, small mucinous carcinoids, adenocarcinoma confined to the mucosa, and tumours in children may be treated by appendicectomy alone at the surgeon's discretion. The 5-year survival rate associated with classical carcinoid is more than 90 per cent. The prognosis of mucinous carcinoid is intermediate between that of classical carcinoid and well differentiated adenocarcinoma. The prognosis of adenocarcinoma is determined by Dukes' stage and is similar, stage for stage, to that of colorectal carcinoma.

Review of the pathologic diagnoses of 2,216 appendectomy specimens

A retrospective review of 2,216 patients surgically treated for a clinical diagnosis of acute appendicitis was performed. In 80% of cases, histologic acute appendicitis was found; 57% of these patients were male. The rate of normal appendectomy was 16%, and females comprised 68% of that group. The remaining 102 cases (4%) were designated as the alternate diagnosis group. Apart from histologic diagnoses that could be considered variants of normal (57) or acute inflammation (20), the alternate diagnosis group included such entities as neoplasm, parasitic infection, mucocele, and diverticulitis.

Gastroenterological emergencies in the tropics

Significant differences exist in the prevalence of most gastroenterological emergencies in tropical compared with temperate countries. Both ethnic and environmental (often clearly defined geographically) factors are relevant. The major oesophageal lesions which can present acutely in tropical countries are varices and carcinoma; bleeding and obstruction are important sequelae. Peptic ulcer disease (and its complications), often associated (not necessarily causally) with Helicobacter pylori infection, has marked geographical variations in incidence. Emergencies involving the small intestine are dominated by severe dehydration, and its sequelae, resulting from secretory diarrhoea, most notably cholera. However, enteritis necroticans ('pig bel' disease), paralytic ileus (sometimes caused by antiperistaltic agents) and obstruction (secondary to luminal helminths, volvulus and intussusception) are other important problems, especially in infants and children. Enteric fever is occasionally complicated by perforation and haemorrhage; the former (which is notoriously difficult to manage) is accompanied by significant mortality. Ileocaecal tuberculosis is a major cause of right iliac fossa pathology--sometimes associated with malabsorption; amoeboma is an important clinical differential diagnosis. The colon can be involved in invasive Entamoeba histolytica infection (which, like complicated enteric fever, is difficult to manage if the fulminant form, with perforation, ensues), shigellosis, volvulus and intussusception. Acute colonic dilatation occasionally follows Salmonella sp., Shigella sp., Campylobacter jejuni, Yersinia enterocolitica and rarely E. histolytica infections. Acute hepatocellular failure is a major cause of morbidity and mortality in the tropics and subtropics. It usually results from viral hepatitis (HBV, sometimes complicated by HDV, and HCV), but there is a long list of differential diagnoses. Hepatotoxicity resulting from herbs, chemotherapeutic agents or alcohol also occurs not infrequently. Chronic liver disease and its sequelae (often long-term results of viral hepatitis) are commonplace. Haematemesis and hepatocellular failure are usually very difficult to manage due to a lack of sophisticated support techniques in developing countries. Invasive hepatic amoebiasis usually responds well to medical management; however, spontaneous perforation can occur and the consequences of this are serious. Pyogenic liver abscess, although far less common than amoebic 'abscess', carries a bad prognosis whatever the method(s) of management. Hydatidosis and schistosomiasis also involve the liver, and helminthiases are important in the context of biliary tract disease. Gall stones are unusual in most tropical settings. Acute pancreatitis is overall unusual, but chronic calcific pancreatitis can present as an acute abdominal emergency.