Necrotizing amebic colitis: a frequently fatal complication

Double Trouble: The Perilous Intersection of Amoebic Colitis and Candida Infection Leading to Colonic Perforation

Amoebic colitis, a parasitic infection caused by Entamoeba histolytica, can lead to severe gastrointestinal symptoms. The clinical manifestations can vary widely, from being an asymptomatic carrier to experiencing severe colitis and even colonic perforation. Surgical treatment for fulminant amoebic colitis and colonic perforation should be carried out at the earliest. Superadded fungal infections in these patients are rare and can significantly complicate the clinical course. Here, we present a unique case of amoebic colitis complicated by a superadded Candida infection, culminating in colonic perforation.

Fulminant necrotising amoebic colitis after corticosteroid therapy for severe COVID-19

Acute fulminant necrotising colitis is an uncommon presentation of amoebiasis, which can be precipitated after corticosteroid therapy. Clinicians treating patients with COVID-19 with corticosteroid therapy should be familiar with this condition to avoid delay in diagnosis. The disease is associated with high mortality, and prompt diagnosis and management are essential for salvaging patients. We report successful management of a patient who developed this complication following administration of steroids for COVID-19.

Management of Entamoeba histolytica in the non-human primates at the Singapore Zoo

Amebic dysentery caused by Entamoeba histolytica accounts for significant morbidity in the non-human primates (NHP) at the Singapore Zoo. This includes the animals in the collection as well as a sizeable free-roaming wild crab-eating macaque (Macaca fascicularis) population. The disease is of great concern because of its zoonotic potential. Passive surveillance, both ante and post-mortem, of NHP displaying clinical symptoms and active surveillance of NHP assessed to be at a higher risk of infection were carried out via fecal real-time polymerase chain reaction (PCR) testing for 4 years. Treatment of the disease with 25 mg/kg metronidazole BID for 10 days followed by 15 mg/kg paromomycin BID for 7 days achieved good clinical resolution in most cases that tested positive. Three diseased NHP with severe clinical signs of weight loss, lethargy, and diarrhea were anesthetized for veterinary diagnostic investigation. Mesenteric lymphadenopathy was consistently seen on ultrasound examination in these severe cases of entamoebiasis. Two animals eventually died of severe chronic enteritis due to the disease. The eradication of entamoebiasis in the NHP at the Singapore Zoo may be complicated by the maintenance of a disease reservoir in wildlife, but a combination of timely treatment and efforts at maintaining biosecurity can help manage the disease in the collection.

Lethal multiple colon necrosis and perforation due to fulminant amoebic colitis: a surgical case report and literature review

Background

Amoebiasis caused by the protozoan species Entamoeba histolytica rarely develops into fulminant amoebic colitis (FAC), but when it does, it shows an aggressive clinical course including colonic perforation, necrotizing colitis, and high mortality. Surgical treatment for FAC patients should be carried out urgently. However, even after surgery, the mortality rate can be 40–50%. Although FAC is one of the most unfavorable surgical diseases with a poor prognosis, there are a few reports on the perioperative diagnosis and management of FAC based on autopsy findings. We herein report the surgical case of a 64-year-old man who developed multiple colon necrosis and perforation due to FAC. A detailed autopsy revealed FAC as the cause of death. Additionally, we reviewed the existing literature on FAC patients who underwent surgery and followed their perioperative diagnosis and management.

Case presentation

A 64-year-old man presented with anorexia, diarrhea, and altered consciousness on arrival to our hospital. Computed tomography revealed a large mass in the upper right lobe of his lung, and the patient was admitted for close investigation. Bloody diarrhea, lower abdominal pain, and hypotension were observed soon after admission. Urgent abdominal contrast-enhanced computed tomography scan revealed extensive intestinal ischemia, intestinal pneumatosis, and free intra-abdominal gas. The preoperative diagnosis was bowel necrosis and perforation with intussusception of the small intestinal tumor. Emergency subtotal colectomy and enterectomy were performed soon after the contrast-enhanced computed tomography. He was taken to an intensive care unit after surgery. However, he could not recover from sepsis and died with disseminated intravascular coagulation and multiple organ failure on the 10th-day post-surgery. A histopathological examination of the resected colon showed transmural necrosis and massive amoebae invasion. He was diagnosed with FAC. An autopsy revealed that he had developed pulmonary large cell carcinoma with small intestinal metastasis. The death was caused by intestinal ischemia, necrosis and the perforation of the residual bowel caused by amoebae invasion.

Conclusions

Since FAC is a lethal disease with a high mortality rate and antibiotic therapies except metronidazole are ineffective, preoperative serological testing and perioperative metronidazole therapy in FAC patients can dramatically improve their survival rates.

Spectrum of CT findings in amebic colitis

Entamoeba histolytica is distributed throughout the world. Invasive amebiasis affects millions of people globally, and the associated complications cause 40,000-100,000 deaths per year. In countries where fecal-oral transmission is unusual, amebic colitis is not common, and the infection may be seen in travelers to and emigrants from endemic areas. Without adequate treatment, amebic colitis may develop into fulminant and become rapidly fatal. With the current increase in global mobility, amebic colitis should be suspected even in patients not in the endemic areas. CT plays an important role in the diagnosis of amebic colitis by demonstrating the presence of colitis with the typical involvement of the cecum and rectum. Pathological features of atypical involvement are also demonstrated. Since preoperative diagnosis can reduce the mortality associated with necrotizing colitis, radiologists need to recognize the typical as well as atypical CT findings of amebic colitis. Considering this requirement, this paper aims to describe the histopathologic features of amebic colitis and to illustrate the spectrum of corresponding CT findings.

Fulminant Necrotising Amoebic Colitis of Whole of Large Bowel: A Rare Complication of a Common Infectious Disease

Background

Fulminant necrotising amoebic colitis (FulNAC) is an uncommon and grave complication of a very common infectious disease widely prevalent in tropical countries. In most of the cases reported, only a segment of large bowel was gangrenous. The involvement of the whole of the large bowel, as in our case, is very rare and has very high mortality ranging from 55% to 100%. Case Summary. A 50-year-old gentleman presented with an acute abdomen with a history of crampy abdominal pain and passage of blood mixed with mucous and loose stools. After resuscitation and investigations, the patient was taken up for laparotomy and the findings showed that the caecum was sloughed off and the entire large bowel had multiple perforations. Subtotal colectomy with ileostomy was performed. Histopathological examination showed evidence of pancolitis with multiple colonies of amoebic trophozoites. Discussion. Entamoeba histolytica is a protozoon that affects the large intestine and liver in humans. There can be various presentations of amoebiasis: asymptomatic infection (90%), symptomatic noninvasive infection (6–8%), acute amoebic colitis (dysentery), or fulminant colitis with perforation. FulNAC is an uncommon complication, difficult to diagnose and treat, and associated with a high mortality rate, ranging from 55% to 100%.

Conclusion

It is important to consider the possibility of fulminant necrotising amoebic colitis (FulNAC) as an uncommon and fatal complication of amoebiasis, especially in tropical countries, where amoebiasis is prevalent. Early diagnosis and antiamoebic treatment, along with urgent aggressive surgical resection of the involved segment and exteriorization of the proximal and distal bowel ends, are shown to reduce mortality.

Surgical Infections in Low- and Middle-Income Countries: A Global Assessment of the Burden and Management Needs

Background: The burden of surgical infections in low- and middle-income countries (LMICs) remains poorly defined compared with high-income countries. Although there are common infections necessitating surgery prevalent across the world, such as appendicitis and peptic ulcer disease, other conditions are more localized geographically. To date, comprehensive assessment of the burden of surgically treatable infections or sequelae of surgical infections in LMICs is lacking. Methods: We reviewed the literature to define the burden of surgical infections in LMICs and characterize the needs and challenges of addressing this issue. Results: Surgical infections comprise a broad range of diseases including intra-abdominal, skin and soft tissue, and healthcare-associated infections and other infectious processes. Treatment of surgical infections requires a functional surgical ecosystem, microbiology services, and appropriate and effective antimicrobial therapy. Systems must be developed and maintained to evaluate screening, prevention, and treatment strategies. Solutions and interventions are proposed focusing on reducing the burden of disease, improving surveillance, strengthening antibiotic stewardship, and enhancing the management of surgical infections. Conclusions: Surgical infections constitute a large burden of disease globally. Challenges to management in LMICs include a shortage of trained personnel and material resources. The increasing rate of antimicrobial drug resistance, likely related to antibiotic misuse, adds to the challenges. Development of surveillance, infection prevention, and antimicrobial stewardship programs are initial steps forward. Education is critical and should begin early in training, be an active process, and be sustained through regular programs.

Diagnosis of colonic amebiasis and coexisting signet-ring cell carcinoma in intestinal biopsy

Amebiasis is uncommon in developed countries. Several case reports in the literature emphasize that both the presenting symptoms and the radiological findings of colonic amebiasis closely resemble more common conditions, such as idiopathic inflammatory bowel disease and gastro-intestinal malignancy. We describe a unique case of colonic amebiasis (amebomas) coexisting with signet-ring cell carcinoma of the ileocecal valve, the cecum and the appendix. Endoscopically, the ulcerated tumor was indistinguishable from the ulcerations and pseudotumors (amebomas) detected in the ascending colon. Histological examination of biopsy specimens revealed the pathognomonic features of protozoa with ingested erythrocytes in combination with signet-ring cell infiltration. The author concludes that amebiasis may not only mimic carcinoma but, rarely, may coexist with carcinoma in the same patient. Clinicians and pathologists should be aware of this possibility in order not to delay diagnosis and treatment of malignant disease.

Fulminant amoebic enteritis that developed in the perinatal period

We present a case of a 30-year-old postpartum woman who delivered by caesarean section at 34 weeks. On postoperative day 9, she was admitted to our hospital in shock. Emergency abdominal surgery was performed. Massive purulent ascites collected in the abdominal cavity and was associated with intestinal necrosis, which extended from the ascending colon to one-third of the descending colon. The necrotic lesion was excised, and an artificial anus was constructed at the ileum end. A histological finding on the 15th day indicated the possibility of amoebic enteritis, and the patient was started on metronidazole therapy. The diarrhoea improved dramatically after metronidazole treatment was started. The patient was able to walk unassisted on the 45th day and was subsequently discharged. Amoebic enteritis has been thought to be epidemic in developing countries, but today, the incidence of amoebic enteritis as a sexually transmitted disease is increasing in developed countries.

Development of perianal ulcer as a result of acute fulminant amoebic colitis

We report a case of acute fulminant amoebic colitis that resulted in the development of a perianal ulcer in a 29-year-old Japanese homosexual man with acquired immunodeficiency syndrome (AIDS). The patient was admitted to our hospital with a persistent perianal abscess that was refractory to antibiotic therapy administered at another hospital. On admission, we observed a giant ulcer in the perianal region. At first, cytomegalovirus colitis was suspected by blood investigations. Ganciclovir therapy was initiated; however, the patient developed necrosis of the skin around the anus during therapy. We only performed end-sigmoidostomy and necrotomy to avoid excessive surgical invasion. Histopathological examination of the surgical specimen revealed the presence of trophozoite amoebae, indicating a final diagnosis of acute fulminant amoebic colitis. The patient’s postoperative course was favorable, and proctectomy of the residual rectum was performed 11 mo later. Amoebic colitis is one of the most severe complications affecting patients with AIDS. Particularly, acute fulminant amoebic colitis may result in a poor prognosis; therefore, staged surgical therapy as a less invasive procedure should be considered as one of the treatment options for these patients.

Fulminant amebic colitis in an HIV-infected homosexual man

We present a case of fulminant amebic colitis in a human immunodeficiency virus (HIV)-infected homosexual man. The patient developed colonic perforation over a short time despite empirical therapy with metronidazole, and underwent right hemicolectomy. Amebic colitis was pathologically diagnosed by identifying invasive trophozoites of Entamoeba in a surgical specimen. Amebic colitis is one of the important differential diagnoses of acute abdomen in HIV-infected patients and/or homosexual men, especially in East Asia. Although fulminant amebic colitis is a rare manifestation of amebiasis, early diagnosis and treatment are thought to be important to improve the outcome of this highly fatal complication.

Infectious agents of food- and water-borne illnesses

Food- and water-borne infections have afflicted mankind since the earliest days of human development and preceded the emergence of civilization. Despite current knowledge of microbial pathogenicity, modern methods of food production and rigorous industrial hygiene, these infections are still commonplace and exact significant health and economic tolls on human populations in all parts of the globe. This review uses data derived from new surveillance networks to survey the current epidemiology of bacterial, protozoan and viral pathogens transmitted by food and water. In addition, we will discuss clinical features of human disease caused by pathogens of current and emerging relevance.

Amebiasis

Amebiasis is an important cause of death from parasitic disease worldwide. The causative organism is Entamoeba histolytica, which has an infective cyst stage and a pathogenic and motile trophozoite stage. The clinical presentation can vary from an asymptomatic carrier state to fulminant colitis and colonic perforation. The majority of patients can be managed medically. However, a small percentage of patients require urgent exploration and resection with an associated high mortality rate. Early recognition and initiation of medical therapy including treatment of asymptomatic carriers are vital to preventing catastrophic outcomes.

Sexually transmitted parasitic diseases

An increasing number of diseases are recognized as being sexually transmitted. The majority of these are bacterial or viral in nature; however, several protozoan and nematode infections can also be transmitted by sexual activity. For most of these diseases, the primary mode of transmission is nonsexual in nature, but sexual activity that results in fecal-oral contact can lead to transmission of these agents. Two parasitic diseases commonly transmitted by sexual contact are amebiasis and giardiasis. The management of these conditions is discussed.

The immunopathogenesis of Entamoeba histolytica

Amebiasis is the disease caused by the enteric dwelling protozoan parasite Entamoeba histolytica. The WHO considers amebiasis as one of the major health problems in developing countries; it is surpassed by only malaria and schistosomiasis for death caused by parasitic infection. E. histolytica primarily lives in the colon as a harmless commensal, but is capable of causing devastating dysentery, colitis and liver abscess. What triggers the switch to a pathogenic phenotype and the onset of disease is unknown. We are becoming increasingly aware of the complexity of the host-parasite interaction. During chronic stages of amebiasis, the host develops an immune response that is incapable of eliminating tissue resident parasites, while the parasite actively immunosuppresses the host. However, most individuals with symptomatic infections succumb only to an episode of dysentery. Why most halt invasion and a minority progress to chronic disease remains poorly understood. This review presents a current understanding of the immune processes that shape the outcome of E. histolytica infections during its different stages.

Antiamoebic drugs for treating amoebic colitis

BACKGROUND

Entamoeba histolytica infection is common in developing countries, and up to 100,000 individuals with severe disease die every year. Adequate therapy for amoebic colitis is necessary to reduce the severity of illness, prevent development of complicated disease and extraintestinal spread, and decrease transmission.

OBJECTIVES

To evaluate antiamoebic drugs for treating amoebic colitis.

SEARCH STRATEGY

In September 2008, we searched the Cochrane Infectious Diseases Group Specialized Register, CENTRAL (2008, Issue 3), MEDLINE, EMBASE, LILACS, mRCT, and conference proceedings. We contacted individual researchers, organizations, and pharmaceutical companies, and checked reference lists.

SELECTION CRITERIA

Randomized controlled trials of antiamoebic drugs given alone or in combination, compared with placebo or another antiamoebic drug for treating adults and children diagnosed with amoebic colitis.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed the eligibility and methodological quality of trials, and extracted and analysed the data. We calculated clinical and parasitological failure rates, relapse, and adverse events as risk ratios (RR) with 95% confidence intervals (CIs), using a random-effects model. We determined statistical heterogeneity and explored possible sources of heterogeneity using subgroup analyses. We carried out sensitivity analysis using trial quality to assess the robustness of the results.

MAIN RESULTS

Thirty-seven trials, enrolling 4487 participants, met the inclusion criteria. Only one trial used adequate methods for randomization and allocation concealment, was blinded, and analysed all randomized participants. Only one trial used a E. histolytica stool antigen test. Tinidazole reduced clinical failure compared with metronidazole (RR 0.28, 95% CI 0.15 to 0.51; 477 participants, eight trials) and was associated with fewer adverse events. Compared with metronidazole, combination therapy resulted in fewer parasitological failures (RR 0.36, 95% CI 0.15 to 0.86; 720 participants, 3 trials).

AUTHORS' CONCLUSIONS

Tinidazole is more effective in reducing clinical failure compared with metronidazole and has fewer associated adverse events. Combination drug therapy is more effective in reducing parasitological failure compared with metronidazole alone. However, these results are based on trials with poor methodological quality so there is uncertainty in these conclusions. Further trials of the efficacy of antiamoebic drugs, with better methodological quality, are recommended. More accurate tests to detect E. histolytica are needed, particularly in countries where concomitant infection with other bacteria and parasites is common.

Amebic perforation of the colon: rare and frequently fatal complication

Amebic colitis perforation is a rare clinical form of amebiasis characteristically associated with high morbidity and mortality. We here present our series of eight patients with amebic colitis perforation. These patients represent 5% of 150 patients hospitalized during the same period for chronic amebic colitis. Only 50% of our patients had a correct preoperative diagnosis, and signs of generalized peritonitis such as rebound tenderness or muscular rigidity were not as common as might have been expected. Our mortality rate was 50% despite aggressive surgical treatment. Every effort should be made to have an early diagnosis, which would lead to early treatment with antiamebic agents, earlier and more limited surgery, and improved survival of these patients.

Amoebiasis

Amoebiasis is the second leading cause of death from parasitic disease worldwide. The causative protozoan parasite, Entamoeba histolytica, is a potent pathogen. Secreting proteinases that dissolve host tissues, killing host cells on contact, and engulfing red blood cells, E histolytica trophozoites invade the intestinal mucosa, causing amoebic colitis. In some cases amoebas breach the mucosal barrier and travel through the portal circulation to the liver, where they cause abscesses consisting of a few E histolytica trophozoites surrounding dead and dying hepatocytes and liquefied cellular debris. Amoebic liver abscesses grow inexorably and, at one time, were almost always fatal, but now even large abscesses can be cured by one dose of antibiotic. Evidence that what we thought was a single species based on morphology is, in fact, two genetically distinct species--now termed Entamoeba histolytica (the pathogen) and Entamoeba dispar (a commensal)--has turned conventional wisdom about the epidemiology and diagnosis of amoebiasis upside down. New models of disease have linked E histolytica induction of intestinal inflammation and hepatocyte programmed cell death to the pathogenesis of amoebic colitis and amoebic liver abscess.

Fulminant amebic colitis: analysis of 55 cases

Fulminant amebic colitis is a rare disease with high morbidity and mortality.

PURPOSE

This study was designed to identify the most frequent clinical and histopathologic features of fulminant amebic colitis and to analyze results of surgical treatment and the existence of risk factors for mortality.

MATERIALS AND METHODS

A retrospective analysis was conducted of clinical and histopathologic data of 55 patients with fulminant amebic colitis. Data were obtained from the files of autopsies and surgical operations that had been performed at a referral center in Mexico from 1943 through 1994.

RESULTS

Median age was 52 (range, 18-79) years. There were 34 men (62 percent) and 21 women (38 percent). Diabetes mellitus and chronic alcoholism were the most frequent diseases in association with fulminant amebic colitis (40 and 31 percent, respectively). The most frequent clinical manifestations were abdominal pain, diarrhea, rectal bleeding, and fever. There was a coexistent amebic liver abscess in 54 percent of patients. The main histopathologic characteristics were necrosis, presence of trophozoites, and acute and/or chronic inflammation. Of 25 patients who underwent surgery, only six survived (operative mortality, 76 percent; overall mortality, 89 percent). The variables that correlated with mortality were longer duration of symptoms, lower count of leukocytes, nonsurgical treatment, nonresective surgical procedure, hospital admission before 1971, and invasion of trophozoites into or through the muscularis.

CONCLUSIONS

The results may help to obtain an earlier diagnosis and establish proper treatment of fulminant amebic colitis.

Recent advances in amebiasis

Advancements in our understanding of amebiasis have been rapid over the decade that I have followed this field. What was identified morphologically for years as Entamoeba histolytica has been redescribed with modern techniques as a complex of two species, the commensal parasite E. dispar and the pathogenic parasite E. histolytica that is the cause of colitis and liver abscess. Antigen detection tests are now available for the rapid detection in stool of the pathogenic species E. histolytica. New understandings of the importance of luminal as well as tissue-active antimebic medications in the treatment of invasive disease have been reached. The groundwork is being laid for an understanding of the protective immune responses to infection, and at the lab bench DNA transfection of the parasite has opened studies of pathogenesis to genetic analysis. While necessarily an incomplete sketch of the field, I have attempted here to highlight some recent and important developments of interest to clinicians and microbiologists.

Fulminant amebic colitis. A morphologic study of four cases

PURPOSE

The morphologic features of fulminant amebic colitis are poorly documented. In this report, we describe the clinical and pathologic findings in four of these cases.

METHODS

The surgical pathology reports and accompanying histologic slides were examined from four patients who underwent surgical resections for fulminant amebic colitis. Clinical information was obtained from the patients' medical records.

RESULTS

Large, geographic mucosal ulcers were typically present and were accompanied by yellow-green pseudomembranes. The muscularis externa was usually attenuated and necrotic, imparting a "wet blotting paper" consistency. Large numbers of amebic trophozoites were present within the inflammatory exudates. The mucosa adjacent to and undermined by the ulcers was often hemorrhagic or inflamed, resembling ischemic colitis or idiopathic inflammatory bowel disease, respectively. Two patients died within four weeks of their surgery. A third patient died one year later as a result of AIDS-related complications. The remaining patient has been lost to follow-up.

CONCLUSION

An uncommon but life-threatening manifestation of intestinal amebiasis is a fulminant colitis. Early surgical intervention and intensive antiamebic chemotherapy are essential for efficacious management.

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.

Fulminant amebic colitis

Amebiasis is the acute and chronic disease produced by Entamoeba histolytica, an entity which occurs in endemic fashion in many of the tropical and subtropical areas of the world, capable of affecting diverse organs of the body, especially the colon. Amebiasis has different clinical forms of presentation, varying from the asymptomatic carrier state to severe, although not frequent, fulminant or necrotizing colitis, characteristically associated with high morbidity and mortality. We hereby report a series of 50 adult patients with fulminating amebic colitis managed at our institution between January, 1971 and July, 1989, with a global mortality of 60%. Early diagnosis, treatment with effective antiamebic agents--specifically metronidazole--and opportune aggressive surgical intervention have resulted in better survival rates. We had no survivors prior to 1970; our current survival rate is still a dismal 40%, indicating the very severe nature of the disease.

Sexually transmitted diseases of the colon, rectum, and anus. The challenge of the nineties

During the past two decades, an explosive growth in both the prevalence and types of sexually transmitted diseases has occurred. Up to 55 percent of homosexual men with anorectal complaints have gonorrhea; 80 percent of the patients with syphilis are homosexuals. Chlamydia is found in 15 percent of asymptomatic homosexual men, and up to one third of homosexuals have active anorectal herpes simplex virus. In addition, a host of parasites, bacterial, viral, and protozoan are all rampant in the homosexual population. Furthermore, the global epidemic of AIDS has produced a plethora of colorectal manifestations. Acute cytomegalovirus ileocolitis is the most common indication for emergency abdominal surgery in the homosexual AIDS population. Along with cryptosporidia and isospora, the patient may present to the colorectal surgeon with bloody diarrhea and weight loss before the diagnosis of human immunodeficiency virus (HIV) disease. Other patients may present with colorectal Kaposi's sarcoma or anorectal lymphoma, and consequently will be found to have seropositivity for HIV. However, in addition to these protean manifestations, one third of patients with AIDS consult the colorectal surgeon with either condylomata acuminata, anorectal sepsis, or proctitis before the diagnosis of HIV disease. Although aggressive anorectal surgery is associated with reasonable surgical results in some asymptomatic HIV positive patients, the same procedures in AIDS (symptomatic HIV positive) patients will often be met with disastrous results. It is incumbent upon the surgeon, therefore, to recognize the manifestations of HIV disease and diagnose these conditions accordingly.

Colectomy for necrotizing amebic pancolitis in early childhood with survival

A case of necrotizing amebic pancolitis in a 6-year-old boy with asplenia, partial situs inversus, and cyanotic congenital heart disease is reported and the literature is reviewed briefly. Our patient was managed successfully by prompt colectomy, ileostomy, a Stamm gastrostomy, and extensive drainage of the peritoneal cavity with administration of metronidazole postoperatively and prolonged jugular vein Broviac catheter hyperalimentation. This child may be the first survivor of total colonic amebic necrosis in childhood. Necrotizing amebic colitis appears to be more hazardous in infancy and childhood than in adult years. Malnutrition and additional illnesses and malformations may produce greater immunocompromise in the very young, placing them at greater risk for the ultimate of amebic intestinal complications, total colonic necrosis and disintegration.