[Amebic liver abscesses developing during R-CHOP chemotherapy in a patient with mantle cell lymphoma].

A 51-year-old man was diagnosed with stage IV mantle cell lymphoma based on terminal ileum biopsy and treated with the R-CHOP regimen. Abdominal CT to assess continuous fever after three courses of R-CHOP revealed three low-density areas in the liver. PCR of the fluid obtained by percutaneous drainage revealed Entamoeba histolytica positivity, although the cultures were negative. Metronidazole treatment achieved cure. The patient was not a homosexual but had an 8-month stay in Lesotho 21 years ago, leading to the possibility that E. histolytica infection at the time continued as an asymptomatic colonization until the initiation of corticosteroid-containing chemotherapy.

Multiple Medium Amoebic Liver Abscesses Successfully Treated with Medication and Comprehensive Percutaneous Catheter Drainage.

Solitary small (<5 cm) amoebic liver abscesses in the right lobe are generally treated using medication alone, while large abscesses are typically treated via a combination of medication and drainage. However, the therapeutic indications for multiple medium (5-10 cm) amoebic liver abscesses remain unclear. We herein report the findings of a 53-year-old woman who was receiving lenalidomide for multiple myeloma and subsequently developed multiple amoebic abscesses. Metronidazole alone was unsuccessful, although metronidazole and repeated percutaneous catheter drainage of the right lobe, left lobe, and thorax proved to ultimately be successful. Therefore, the successful use of medication alone may be associated with the total combined abscess volume.

The 29-kilodalton thiol-dependent peroxidase of Entamoeba histolytica is a factor involved in pathogenesis and survival of the parasite during oxidative stress.

The 29-kDa surface antigen (thiol-dependent peroxidase; Eh29) of Entamoeba histolytica exhibits peroxidative and protective antioxidant activities. During tissue invasion, the trophozoites are exposed to oxidative stress and need to deal with highly toxic reactive oxygen species (ROS). In this investigation, attempts have been made to understand the role of the 29-kDa peroxidase gene in parasite survival and pathogenesis. Inhibition of eh29 gene expression by antisense RNA technology has shown approximately 55% inhibition in eh29 expression, maximum ROS accumulation, and significantly lower viability in 29-kDa downregulated trophozoites during oxidative stress. The cytopathic and cytotoxic activities were also found to decrease effectively in the 29-kDa downregulated trophozoites. Size of liver abscesses was substantially lower in hamsters inoculated with 29-kDa downregulated trophozoites compared to the normal HM1:IMSS. These findings clearly suggest that the 29-kDa protein of E. histolytica has a role in both survival of trophozoites in the presence of ROS and pathogenesis of amoebiasis.

Protective activity of picroliv on hepatic amoebiasis associated with carbon tetrachloride toxicity.

BACKGROUND AND OBJECTIVE: Picroliv, isolated from the root and rhizome of Picrorhiza kurroa, is known to have significant hepatoprotective activity. Its effects against Entamoeba histolytica induced liver damage are not studied. This study aims to evaluate the hepatoprotective action of picroliv against the hepatotoxic changes induced by carbon tetrachloride (CCl(4)) and E. histolytica infection in three animal models. METHODS: Mastomys, gerbils and albino Druckray rats were used in this study. A total of 30 animals were used for each model and divided into five groups of six animals each. Group I consisted of normal animals. The rest received six doses of CCl(4) intraperitoneally. Group II served as hepatotoxic control. The remaining animals were infected intraperitoneally with E. histolytica trophozoites, of which group III was the hepatotoxic plus amoeba infected control. The remaining animals were divided into two groups, one received hepatoprotective agent picroliv and the other silymarin. All animals were sacrificed seven days post amoeba infection. RESULTS: Increase in the enzyme levels induced by CCl(4) was further elevated after E. histolytica infection. Pinpoint abscesses were found to develop only in gerbils after E. histolytica infection. Picroliv was found to possess hepatoprotective activity against amoebic liver abscess. INTERPRETATION AND CONCLUSION: Significant recovery obtained in serum enzyme levels in all animal models and against amoebic liver abscess in gerbils on treatment with picroliv indicated that picroliv possesses therapeutic activity against E. histolytica induced hepatic damage.

Los modelos experimentales in vivo en la amibiasis / In vivo experimental models of amebiasis

La utilización de los modelos experimentales in vivo en la amibiasis, ha proporcionado información importante sobre los mecanismos involucrados en la relación huésped-parásito que determinan la producción de la enfermedad. En el laboratorio se han utilizado varios roedores para estudiar la amibiasis intestinal y la hepática. Para la primera, el modelo del "asa cecal lavada y cerrada" en el cobayo y el hámster ha sido útil para el análisis de las etapas tempranas del daño a la mucosa. También se ha logrado producir lesiones tempranas intestinales en el jerbo por inoculación intracecal de amibas en cultivo monoxénico. Para los modelos de amibiasis hepática, se han utilizado el hámster y el jerbo como animales susceptibles, y la rata y el cobayo como animales resistentes. El análisis morfológico de las lesiones hepáticas en losanimales susceptibles mostró que las células inflamatorias del huésped participan en la producción del daño hepático. La resistencia a la producción de absceso hepático amibiano en ratas y cobayos se debe en parte a los leucocitos polimorfonucleares en la rata y los macrófagos en el cobayo. La completa caracterización y estandarización de los diversos modelos de amibiasis en roedores constitutyen las bases para otros estudios biomédicos de importancia para el control de la enfermedad

Amoebic disease precipitated by corticosteroids prescribed for tuberculous pleural effusions.

One case of ameobic abscess of the liver and one case of amoebic dysentery are described in two patients who were prescribed corticosteroids as part of the intreatment for tuberculous pleural effusion. In both cases routine stool examinations prior to steroid therapy were negative for cysts or trophozoites of E. histolytica.

Progesterone-induced amoebic liver abscess in guinea-pigs--a new model.

An experimental model of hepatic amoebiasis in guinea-pigs, simulating the natural infection in man, induced by progesterone following intracaecal inoculation of Entamoeba histolytica has been developed. On Day 3 after infection, 60% of the animals developed amoebic liver abscess, but on Days 7, 11, 15, 20 and 35 after infection liver involvement was recorded in all the animals. No animal in the control group developed hepatic amoebiasis. Severity and frequency of caecal lesions was greater in the control groups than in the experimental group receiving progesterone injections. The antiamoebic antibody levels were slightly higher in the experimental group as compared to the control group.

An unusual complication of corticosteroid therapy for sarcoidosis.

This report describes the rapid development of an amoebic liver abscess in a patient receiving prednisone by mouth for hypercalcaemia associated with sarcoidosis. The diagnosis and treatment of amoebiasis in this setting are discussed.