Amoebic liver abscess in USA: a population-based study of incidence, temporal trends and mortality.

BACKGROUND: Amoebic liver abscess (ALA) may be associated with significant morbidity and mortality, but nationwide American data is unavailable. Our objective was to describe ALA epidemiology and outcomes in USA from a population-based perspective. METHODS: Patients hospitalized with ALA between 1993 and 2007 were identified using the Nationwide Inpatient Sample. Patient characteristics, interventions and outcomes including mortality were determined. The annual incidence of ALA and temporal trends were determined using the negative binomial regression models. RESULTS: Between 1993 and 2007, 848 hospitalizations for ALA, corresponding to ∼4100 hospitalizations nationwide, were identified. The annual incidence was 1.38 per million population with a 2.4% [95% confidence interval (CI) 0-4.8%; P=0.06] average annual decline during this study. Most patients were hospitalized in western (54%) and southern states (27%), and 48% were Hispanic. Males (incidence rate ratio vs. females: 4.53; 95% CI 4.19-4.90) had the highest incidence rates. Percutaneous and surgical drainage was required in 48 and 7% of patients respectively. Although length of stay [median, 6 days; interquartile range (IQR) 4-10] and hospital charges (US$25,345; IQR US$15,030-42, 275) were substantial, in-hospital mortality was rare (0.8%). Females [odds ratio (OR) 6.12; CI 1.39-26.8], patients ≥ 60 years (OR 13.3; 95% CI 2.5-71.5), and those with ≥ 3 comorbidities (OR 5.80; 95% CI 1.30-25.8), particularly malnutrition, had an increased risk of death. CONCLUSIONS: ALA is rare and the incidence has decreased in USA. Young, Hispanic males in southwestern states are most frequently affected. Mortality caused by ALA is lower than what was reported previously.

Morbidity due to Schistosoma mansoni--Entamoeba histolytica coinfection in hamsters (Mesocricetus auratus).

Data on Schistosoma mansoni-Entamoeba histolytica coinfection are scarce in the literature. In the present study, hamsters that had been infected for 70 days with Schistosoma mansoni (LE strain) were inoculated via the portal vein with two strains of trophozoites of Entamoeba histolytica: ICB-EGG (highly virulent) and ICB-RPS (non-virulent). The most evident result of coinfection was increased morbidity and mortality, in comparison with either of the infections alone. Histologically, there were no evident signs of interaction between these two infections. The morphological findings of schistosomal granuloma and amoebic abscesses in the liver were similar to those seen in the respective single-infection controls. However, there was severe wasting of the animals with both infections and greater numbers of amoebic lesions in their livers. The results obtained indicated that schistosomiasis aggravates the course of amoebiasis in hamsters.

Morbidity due to Schistosoma mansoni - Entamoeba histolytica coinfection in hamsters (Mesocricetus auratus)

Data on Schistosoma mansoni-Entamoeba histolytica coinfection are scarce in the literature. In the present study, hamsters that had been infected for 70 days with Schistosoma mansoni (LE strain) were inoculated via the portal vein with two strains of trophozoites of Entamoeba histolytica: ICB-EGG (highly virulent) and ICB-RPS (non-virulent). The most evident result of coinfection was increased morbidity and mortality, in comparison with either of the infections alone. Histologically, there were no evident signs of interaction between these two infections. The morphological findings of schistosomal granuloma and amoebic abscesses in the liver were similar to those seen in the respective single-infection controls. However, there was severe wasting of the animals with both infections and greater numbers of amoebic lesions in their livers. The results obtained indicated that schistosomiasis aggravates the course of amoebiasis in hamsters.

Dados sobre a co-infecção Schistosoma mansoni-Entamoeba histolytica são escassos na literatura. No presente estudo, hamsters com 70 dias de infecção por Schistosoma mansoni (cepa LE) foram inoculados com trofozoítos de Entamoeba histolytica, cepa ICB-EGG (virulenta) e cepa ICB-RPS (não virulenta), via veia porta. O mais evidente resultado da co-infecção foi o aumento da morbidade e mortalidade, quando comparado com os animais com somente uma das infecções. Histologicamente, não houve sinais evidentes da interação entre as duas infecções. O aspecto morfológico do granuloma esquistossomótico e do abcesso hepático amebiano são similares aos observados nos controles, com somente uma infecção. Entretanto, foi observado que os animais co-infectados apresentavam-se mais debilitados e com maior número de lesões amebianas no fígado. Os resultados obtidos indicam que a esquistossomose agrava o curso da infecção amebiana em hamsters.

Amibiasis hepática en el Instituto Nacional de Pediatría de 1971-1994 / Hepatic amibiasis at the National Pediatrics Institute from 1971 to 1994

Se analizaron 217 casos de amibiasis hepática (AH) con la descripción de sus características clínicas de laboratorio y gabinete, así como los posibles factores de riesgo para el desarrollo de complicaciones y mortalidad y las diferentes modalidades terapéuticas. El promedio anual de ingreso disminuyó de 13 casos durante el periodo de 1971 a 1984, a 4.4 en los últimos años. El 56.6 por ciento fueron menores de cinco años; no obstante, sólo 0.02 por ciento (6) eran menores de un año, 83 por ciento tenían absceso único, con franco predominio en el lóbulo hepático derecho en 73 por ciento. El diagnóstico (Dx) se sospechó clínicamente al ingreso en el 82 por ciento de los casos; en tres pacientes el Dx se hizo en autopsia. El ultrasonido (ULTS), la gamagrafía y la hemaglutinación confirmaron el Dx en todos los pacientes. El ULTS como método de diagnóstico no invasivo fue de gran utilidad ya que los hallazgos sugirieron el Dx en la mayoría de los casos, lo que permitió el pronto inicio del tratamiento. Se observaron complicaciones (ruptura a áreas adyacentes) en 30 por ciento, la más frecuente fue la ruptura del absceso a la cavidad torácica. La ruptura del absceso es un signo de gravedad que requiere tratamiento con aspiración o drenaje quirúrgico. El tiempo de evolución fue significativamente mayor en los niños con complicaciones (23.7 ñ 20.3 vs 16.9 ñ 12.4 días, p<0.05). Ciento setenta y cuatro pacientes recibieron tratamiento con dehidroemetina y metronidazol y el resto solo metronidazol sin diferencia significativa. La recuperación clínica fue significativamente más rápida en los pacientes no complicados que tuvieron además del tratamiento médico punción cerrada del absceso, particularmente en abscesos con diámetro igual o mayor a 10 cm. La mortalidad se redujo de 8 por ciento en los primeros 14 años a ningún fallecimiento en el último periodo. El alto índice de sospecha diagnóstica y el inicio temprano de metronidazol con el drenaje oportuno de los abscesos complicados, probablemente han contribuido a una mejor sobrevida en los últimos años

La amibiasis y el absceso hepático amibiano en México, un problema de salud pública de actualidad / The amebiasis and the amebic liver abscess in Mexico, a present time public health problem

Antecedentes: La amibiasis continúa siendo un problema de salud pública a nivel mundial. En México es un motivo de consulta frecuente y tan sólo en el Instituto Mexicano del Seguro Social se atienden más de medio millón de casos al año. La información epidemiológica en México es aún incompleta. Objetivo: Describir el comportamiento secular de la amibiasis en todas sus formas de presentación clínica y del abseco hepático amibiano, en la población mexicana y en la amparada por IMSS-Solidaridad. Métodos: Se realizó un estudio ecológico de tendencia. Se graficaron las tasas de incidencia de la amibiasis en todas sus formas, así como del absceso hepático amibiano por cada uno de los años de período analizado. Resultados: La incidencia de amibiasis en todas sus formas mostró una tendencia estable en el período de estudio, situación similar a lo observado con el absceso hepático amibiano. La amibiasis es más frecuente durante el primer año de vida. Por el contrario, el absceso hepático amibiano muestra un patrón de "J" invertida, es decir, la ocurrencia es mayor en los extremos de la vida. La letalidad ha mostrado una tendencia al descenso constante: Conclusiones: La amibiasis en México es un reflejo de las condiciones socioeconómicas y de la cultura inacabada mexicana. Es necesario propiciar la educación para la salud, al igual que el mejor diagnóstico y detección de portadores asintomáticos. Con las madres portadoras debieran redefinirse las políticas de salud, dada la elevada frecuencia de amibiasis y absceso hepático amibiano en los menores de un año.

Perforated amebic liver abscess: clinical analysis of 110 cases.

In this study of 503 consecutive cases of amebic liver abscess documented during a 21-year period, 110 (22%) were complicated by perforation. Perforation sites included pleuropulmonary structures (79 cases, 72%) subphrenic space (15 cases, 14%); and peritoneal cavity (11 cases, 10%). The less common sites were the thoracic and abdominal wall, pericardial sac, bile duct, kidney, mediastinum, colon, and right flank. Trophozoites were recovered in 29% of cases. For the rest of the cases, diagnosis was based on the clinical manifestations and the dramatic response to a therapeutic trial of amebicides. Open surgical drainage was done in 10 of 11 patients who had peritoneal perforation; 6 of them were cured and 5 died. Of 97 patients with perforation sites other than the peritoneal cavity, 64 were treated with metronidazole in addition to needle aspiration and/or percutaneous catheter drainage, and all achieved complete remission without relapse during subsequent follow-up. Of the 36 cases treated with metronidazole alone, 22 (61%) were cured. The mortality rate in the group with perforated abscess was 17% (19/110), compared with 5% (25/503) in the whole series. The results suggested that (1) amebic liver abscess can be difficult to diagnose, especially when the pathogen is not isolated; and (2) metronidazole combined with needle aspiration and/or percutaneous catheter drainage is the treatment of choice for amebic liver abscess with perforation.

Therapeutic approach to hepatic abscesses.

Thirty-five patients with hepatic abscesses were treated at our institution during an 8-year period. Twenty-nine patients had bacterial abscesses, and six patients had amoebic abscesses. The patients were admitted with fever (95%), right upper quadrant pain (63%), and nausea and vomiting (40%) as the most common symptoms. Eleven patients had some inciting cause for the abscess formation; the remaining 18 bacterial abscesses were cryptogenic. The primary abnormal test results were leukocytosis (91%) and liver enzyme elevations (80%). All patients with amoebic abscesses were serologically positive for amoebic infection. Computed tomography (CT) was the most effective imaging modality for diagnosis. Twenty patients were treated with open surgical drainage, 11 with percutaneous drainage, and 4 with antibiotics alone. Three of the four latter patients had amoebic abscesses. Abscesses in two patients initially treated with percutaneous drainage did not resolve, and the patients ultimately required surgery. The remaining indications for surgery were concomitant conditions requiring surgical intervention or inaccessibility of the abscess to percutaneous drainage. Antibiotics were given to all patients, with treatment duration from 10 to 60 days. The hospital mortality was 6% due to sepsis and a postoperative myocardial infarction in one patient, and perioperative myocardial infarction in another; overall morbidity was 20%. At a mean follow-up of 13 months, all surviving patients had resolution of the abscess shown by either CT (11 patients) or clinical examination (22 patients). We conclude that effective drainage, whether it be surgical or percutaneous, and appropriate antibiotic coverage are the mainstays of therapy for hepatic abscesses.

Amoebic liver abscess. Review of 220 cases.

Two hundred and twenty cases of amoebic liver abscess were seen between 1981-1986. The majority were young or middle aged males belonging to the lower socio-economic group and 85% gave a history of drinking toddy (fermented palm juice). The highest incidence of the disease occurred during the peak toddy season (April to July). Toddy drinkers become susceptible perhaps because of the large dose of Entamoeba histolytica and bacteria ingested with the drink, associated malnutrition, poor hygiene, hepatic dysfunction and possible suppression of amoebistatic substance. Useful investigations consisted of skiagram and ultrasonography, the later being sometimes used to guide the aspiration needle to abscesses situated at unconventional sites. Over 88 per cent responded well to conservative treatment with aspiration(s). Laparotomy was required in slightly over 10% of cases and in these the mortality was 12% as compared to 2% with conservative treatment. Although a large amount of liver tissue appears to be destroyed, the residual liver damage is clinically, biochemically, macroscopically and microscopically minimal.

[Surgical treatment of amebic liver abscess]. / Tratamiento quirúrgico del absceso hepático amibiano.

Results of surgical treatment of hepatic amebic abscess in three hospitals during last three years are presented. Seventy four percent of patients admitted with complications of amebiasis have liver abscess. Of them 22% require surgical treatment and mortality is 8%. Nineteen years ago the amount of patients admitted with amebic complications was greater and a larger number of patients were operated; however mortality has not changed.

Ruptured amebic liver abscess.

We treated two patients with a ruptured amebic liver abscess. The diagnosis was made at a relatively early stage and treatment was successful for one patient, but an accurate diagnosis of liver abscess was not made and invasive extraintestinal amebiasis led to multiple organ failure and to death for the other. Neither patient had been outside of Japan, and both were heterosexual. The origins of Entamoeba histolytica infection could not be determined. Though the mortality rate is high in cases of ruptured amebic liver abscess, appropriate management can lead to a good prognosis.

[Amebiasis. Surgical treatment in 1989]. / Amibiasis. Tratamiento quirúrgico en 1989.

Even when the number of patients with invasive amebiasis has decreased, the internist and surgeon must be alert in case that the patient requires an operation. Amebic liver abscess is treated medically; percutaneous evacuation is rarely used and surgical drainage is made when there is not response to medical treatment or there is high risk of abscess rupture. Operation is mandatory when the abscess has ruptured to the abdominal cavity or through the pericardial sac. In fulminant colitis it is necessary to resect the diseased portion of the colon without primary anastomoses. Amebic apendicitis is difficult to diagnosis before an operation. It may be suspected in cases of apendicitis if the cecal wall is inflammed. Colon ameboma requires medical treatment except if it is associated with necrosis or perforation. In a four year period (1985-1988) 294 patients with diagnosis of invasive amebiasis were admitted to three hospitals of the Instituto Mexicano del Seguro Social in Mexico City. 218 had hepatic abscess, 45 required surgical drainage with four deaths (9%) and four not operated patients died. In this series only four patients had their abscess drained percutaneously. 31 patients with amebic colitis were treated; three required colonic resection with one death. Ameboma was seen in five patients and there were 11 cases of amebic apendicitis. No deaths occurred in these last two groups.

[Amebiasis in Transcaucasia and in mountainous desert locales]. / Amebiaz v Zakavkaz'e i v usloviiakh gorno-pustynnoi mestnosti.

The history of the amebiasis investigation in Transcaucasia is presented. 16 cases of amebiasis are described. Data for 1982-1988 on the amebiasis in the moorland are given (41 fatal case).

Tratamiento quirúrgico del absceso hepático amibiano: experiencia durante los últimos años en el Instituto Nacional de la Nutrición Salvador Zubirán / Surgical treatment of hepatic amebic abscess: 10 years' experience

A pesar del advenimiento de efectivos fármacos antiamibianos, el absceso hepático amibiano (AHA) continúa siendo una entidad común en nuestro medio. Se revisaron retrospectivamente 38 pacientes que fueron sometidos a tratamiento quirúrgico para AHA de 1976 a 1985 en el Instituto Nacional de la Nutrición Salvador Zubirán. Las principales manifestaciones clínicas fueron fiebre, dolor abdominal, hepatomegalia e icterica. Las principales indicaciones quirúrgicas fueron falta de respuesta al tratamiento médico, sindrome abdominal agudo y sospecha de perforación. La mortalidad y morbilidad operatoria fueron 29 y 13%, respectivamente. Lo alto de estas cifras refleja que el AHA es una enfermedad severa que debe ser tempranamente diagnosticada y manejada. Las indicaciones principales para cirugía son la falta de respuesta al tratamiento médico o la existencia de complicaciones

Liver abscess. Review of a 12-year experience.

Experience with liver abscess was reviewed to determine whether new trends in treatment have altered clinical outcome. Thirty-one cases of liver abscess were identified from 1973 to 1985. In this group there were ten deaths for a mortality rate of 32 per cent; the primary disease accounted for seven deaths. Significant predictors of liver abscess mortality were multiple abscesses, elevated bilirubin levels, and underlying disease. Percutaneous drainage was effective in three of four patients and should be attempted before operative intervention in selected patients.

Amebic liver abscess: a study of 11 cases compared with a series of 38 patients with pyogenic liver abscess.

Amebic liver abscess is an uncommon disease in the northern states of North America with 11 cases seen among approximately 500,000 Mount Sinai Hospital admissions over a 16-year period. Five of 11 cases originated in, or had recently visited South America. In three of these, and two patients with concomitant intestinal amebiasis, the diagnosis was suspected on admission. Diagnosis after admission was rapid, mean 5 days, compared with a mean of 13 days in pyogenic liver abscess. There was a higher incidence of male patients, nine males versus two females which was greater than the excess found in our pyogenic abscesses, 22 versus 16. Multiplicity was less common than in pyogenic abscess, 27 versus 50%, respectively. All three patients with multiple abscesses survived with surgical drainage and antibiotic therapy despite numerous complicating factors, including secondary bacterial infection. One patient resolved with drug treatment only; all others were treated with drugs and concomitant drainage; surgical drainage in earlier cases, and percutaneous drainage more recently. There was a single postoperative death. Drug treatment is the first therapeutic modality, and if recovery is delayed more than 2 days percutaneous aspiration should be carried out. This was successful in four cases. Surgery should seldom be required with present methods of accurately localizing amebic liver abscess, but is essential for ruptured abscess with peritonitis, and liver abscess with associated intestinal problems such as toxic megacolon, colonic perforation, or fulminating colitis. There has been a significant reduction in mortality of amebic liver abscess over the past 50 years and particularly within the past decade.(ABSTRACT TRUNCATED AT 250 WORDS)