Amoebic Hepatic Abscess Research Articles

A rare hepatic mass in an Italian resident

BackgroundAmebiasis is a rare condition in developed countries but epidemiologically growing. Clinical manifestation may range from asymptomatic to invasive disease, amoebic liver abscess being the most common manifestation. We report a peculiar case of left hepatic amoebic liver abscess in a patient without a well-known source of infection and presenting with left portal vein thrombosis.Case presentationPatient, working as longshoreman, presented with complaints of remittent-intermittent fever lasting from 2 weeks. Physical examination was normal. Blood tests showed mild anemia, neutrophilic leukocytosis and elevated inflammation markers. Chest x-rays was normal. Abdominal ultrasound showed multiple hypoechoic liver masses. CT-scan of abdomen showed enlarged left liver lobe due to the presence of large abscess cavity along with thrombosis of left portal vein. The indirect hemagglutination test for the detection of antibodies to Entamoeba histolytica (Eh) was positive. Ultrasound-guided percutaneous drainage revealed “anchovy sauce” pus. Metronidazole and a follow up imaging at 3 months showed resolution of abscess cavity.ConclusionThis case shows that amoebic liver abscess is possible even in first world country patients without travel history. Left sided abscess and portal vein thrombosis are rare and hence reported.

Amoebic hepatic and renal abscesses complicating amoebic colitis

Amoebic hepatic and renal abscesses complicating amoebic colitis

Anti‐amoebic Effect of Gossypol in Golden Hamsters with Experimental Hepatic Amoebic Abscess

Although metronidazole is an effective anti-amoebic medication, it is mutagenic and some strains of Entamoeba histolytica resistant to this drug have begun to appear. The search for new anti-amoebic compounds is, therefore, justified. We have previously found that gossypol has a potent in-vitro anti-amoebic effect; we now show that this compound is also effective in-vivo. Hamsters with experimental amoebic hepatic abscess were fed acetic acid gossypol (0–45 mg kg−1) or metronidazole (30 or 45 mg kg−1) for 5 or 10 days. The experimental amoebic hepatic abscess size and the in-vitro cell density reached by trophozoite cultures from the experimental amoebic hepatic abscesses were scored. Gossypol and metronidazole reduced the experimental amoebic hepatic abscess. The smallest effect of gossypol was obtained with 5–45 mg kg−1 (23–31% score reduction) administered for 5 days whereas the most effective treatment corresponded to 30 mg kg−1 gossypol for 10 days (90% score reduction). Gossypol at 45 mg kg−1 for 10 days was toxic. The anti-amoebic effect of 30 mg kg−1, judged as the cell density score reduction compared with the control group, was comparable with that produced by 30 mg kg−1 metronidazole administered for 10 days. Although in molar concentration terms, gossypol was nine times more potent than metronidazole, the margin between the most effective and lethal doses of gossypol was relatively narrow. A combination of gossypol and metronidazole could be a more efficacious and less toxic anti-amoebic combination than the separate drugs.

In-vitro Additive Synergistic Anti-amoebic Effect of a Metronidazole—Gossypol Blend

Gossypol has a potent anti-amoebic effect on both Entamoeba histolytica axenic cultures and experimental amoebic hepatic abscess. However, the margin between the in-vivo effective dose and the toxic dose in hamsters is relatively small. While metronidazole is widely used as an anti-amoebic medication, it is considered a possible carcinogen in man. With the aid of the Basic Sequential Analytical Simplex Method we tested the effectiveness of 12 metronidazole-gossypol blends where the concentration of each drug was systematically varied. Amoebic growth inhibition was observed (33–71% with respect to controls) using blends containing metronidazole (50–154 nM) and gossypol (5–16 nM). The combination containing metronidazole (88.61 nM) and gossypol (9.95 nM) caused 62% amoebic growth inhibition. These concentrations where 50% lower than those required to produce an equivalent effect using metronidazole or gossypol alone. Thus, the actions of metronidazole and gossypol against E. histolytica are additive. Accordingly, the in-vivo application of an appropriate combination of metronidazole and gossypol could be as effective as each drug alone, but less toxic to the host.

Influence of inflammation on parasitism and area of experimental amoebic liver abscess: an immunohistochemical and morphometric study

The influence of inflammation on the number of trophozoites and on the murine amoebic liver abscess area following infection with Entamoeba histolytica and E. dispar was evaluated. Immunohistochemistry and digital morphometry were used to identify and quantify the trophozoites, neutrophils, macrophages, and lesions. Positive correlation was observed between the number of trophozoites and inflammatory cells. A significant decrease in parasitism and inflammation in groups treated with dexamethasone was observed. The scarceness or absence of trophozoites in the treated groups suggest the importance of the inflammatory response in the production of amoebic hepatic abscesses in spite of the inherent virulence of the parasite being decisive in the establishment of the lesion.

Modulation of amoebic hepatic abscess by the parasympathetic system

The neuro-immune network, in which the vagus nerve is involved, provides feedback between its afferent branches for signalling central nervous system from sites of injury through cytokines and its efferent branches, which release acetylcholine, an anti-inflammatory neurotransmitter. For gain insight into the parasympathetic mechanisms participating in the inflammatory response in the liver, we studied the effects of a vagotomy on the innate immune response in hamsters with amoebic liver abscess. At 7 days post-infection, compared to the control, liver parasympathectomy resulted in a larger abscess size, a greater production of collagen fibres, fewer trophozoites, increased serum levels of IL-10 and IFN-γ and increased numbers of IL-10 and IFN-γ-positive cells in situ, with no change in the number of macrophages and NK cells. Data indicate that the vagotomy disrupted the inflammatory response, causing an increase in the response against infection, then could favour the innervation of the liver by the sympathetic nervous system and would then take the control of the immune response by stimulating the conversion of macrophages to epithelioid cells; and through increased IL-10 production would induce the hepatic stellar cells to become myofibroblast collagen producer cells, thus forming a barrier of collagen and blocking trophozoite migration.

Anti-inflammatory defense mechanisms of Entamoeba histolytica

The monocyte locomotion inhibitory factor (MLIF), a heat-stable oligopeptide found in the supernatant fluid of Entamoeba histolytica axenic cultures, may contribute to the delayed inflammation observed in amoebic hepatic abscess. This factor was isolated by ultra-filtration and high powered liquid chromatography, obtaining a primary Met-Gln-Cys-Asn-Ser structure, identified afterwards as the carboxyl-terminal (…Cys-Asn-Ser) active site. The selective anti-inflammatory effects of the pentapeptide have been observed in both in vitro and in vivo models, using a synthetic pentapeptide to maintain the same anti-inflammatory conditions during the experimental assays. Anti-inflammatory effects observed include inhibition of human monocyte locomotion and the respiratory burst in monocytes and neutrophils, increasing expression of anti-inflammatory cytokines and inhibiting expression of the adhesion molecules VLA-4 and VCAM, among others. In this review, we will describe the effects of MLIF detected so far and how it might be used as a therapeutical agent against inflammatory diseases.

Effect of the monocyte locomotion inhibitory factor (MLIF) produced by E. histolityca on cytokines and chemokine receptors in T CD4+ lymphocytes.

Entamoeba histolytica produces Monocyte Locomotion Inhibitory Factor (MLIF), which may contribute to the delayed inflammation observed in amoebic hepatic abscesses. Leukocytes are affected through the modulation of cytokine expression and/or production. We evaluated the effects of MLIF on the activation and production of intracellular cytokines in human CD4+ T lymphocytes by flow cytometry. Cells were stimulated for 24 h with PMA, MLIF, or PMA+MLIF. Cellular activation was measured using anti-CD69. Th1/Th2 production was studied by the expression of intracellular cytokines and cytokine/chemokine receptors. MLIF increased CD69 and induced the over-expression of the IL-lss, IFN-gamma, IL-2, IL-4, and IL-10 intracellular cytokines; PMA+MLIF inhibited Th1 cytokine (IFN-gamma) and increased Th2 cytokines (IL-4 and IL-10). The co-expression of the cytokine and chemokine receptors IFN-gamma/CCR5 and IL-1ss/CCR5 was inhibited by PMA+MLIF and Th2 co-expression was increased. MLIF effects varied depending on the conditions. MLIF alone activated the Th1 and Th2 cytokines and cytokine/receptor expression; however, PMA+MLIF increased the expression of Th2 but inhibited it in Th1.

Manifestations pleuropulmonaires révélatrices de l’amibiase hépatique

During a mission in ex-Yugoslavia between 2001 and 2004, three French soldiers were sent home because of right pneumopathy, right pleurisy after appendicectomy, haemoptysis and liver haematoma, respectively. They previously were stationed in Africa and/or South America. The initial diagnosis was quickly modified: pleuropulmonary manifestations of amoebic hepatic abscess in two cases, and pleuropulmonary amoebiasis in the last case. The outcome was favourable with standard anti-amoebic treatment. The reports illustrate the possibility of hepatic amoebiasis with local pleuropulmonary manifestations and an exceptional case of pleuropulmonary amoebiasis with hepatobronchial fistula. The authors report this experience because it demonstrates that amoebiasis in European countries remains an often forgotten diagnosis. Although known for a long time in developing countries, amoebiasis in the military or in tourists should be systematically considered.

Effect of the monocyte locomotion inhibitory factor (MLIF) produced by E. histolityca on cytokines and chemokine receptors in T CD4+ lymphocytes

Entamoeba histolytica produces Monocyte Locomotion Inhibitory Factor (MLIF), which may contribute to the delayed inflammation observed in amoebic hepatic abscesses. Leukocytes are affected through the modulation of cytokine expression and/or production. We evaluated the effects of MLIF on the activation and production of intracellular cytokines in human CD4+ T lymphocytes by flow cytometry. Cells were stimulated for 24 h with PMA, MLIF, or PMA+MLIF. Cellular activation was measured using anti-CD69. Th1/Th2 production was studied by the expression of intracellular cytokines and cytokine/chemokine receptors. MLIF increased CD69 and induced the over-expression of the IL-lss, IFN-gamma, IL-2, IL-4, and IL-10 intracellular cytokines; PMA+MLIF inhibited Th1 cytokine (IFN-gamma) and increased Th2 cytokines (IL-4 and IL-10). The co-expression of the cytokine and chemokine receptors IFN-gamma/CCR5 and IL-1ss/CCR5 was inhibited by PMA+MLIF and Th2 co-expression was increased. MLIF effects varied depending on the conditions. MLIF alone activated the Th1 and Th2 cytokines and cytokine/receptor expression; however, PMA+MLIF increased the expression of Th2 but inhibited it in Th1.

Análisis de factores asociados al fracaso del tratamiento médico del absceso hepático amebiano

To identify the laboratory and ultrasound factors that could predict the response to medical treatment of amoebic liver abscess.Retrospective study of patients diagnosis with amoebic liver abscess in Hospital Central in San Luis Potosí, Mexico. We included patients greater than 15 years of both sexes. We excluded those with probable pyogenic abscess, immunosupression, history of abdominal or biliary surgery, abdominal neoplasm abdominal or sepsis. We identified patients with good response to medical treatment and patients who needed the abscess drained. We studied the ultrasound findings, plasma levels of albumin, alkaline phosphatase and bilirubin.We analysed 45 patients, 31 had a good response (controls) and 14 needed drainage (cases). The medians of the variables with statistical significance in bivariate analysis were: albumin 2.65 g/dl and 1.7 g/dl (p < 0.001); alkaline phosphatase 133 U and 259 U (p = 0.02) and diameter of absences 5.9 cm and 9.95 cm (p < 0.001), controls and cases respectively. By logistic regression the diameter of the abscess showed a determination coefficient of 0.447 (p < 0.05) and OR = 14.85 (95% CI, 2.11-104.9) for drain if it was > or = 8 cm.A diameter bigger than 8 cm in hepatic amoebic abscess is associated with failure of medical treatment. Low albumin could be related to malnutrition and increased alkaline phosphatase with extrinsic compression of extrahepatic conducts due to big abscesses.

Ultrasound-controlled drainage of amebic abscess of the liver in Mexico

Drainage of a hepatic amoebic abscess by puncture guided by ultrasonography is described by means of an example. The treatment by puncture has the advantage of shortening clinical treatment. It should be combined with pharmacotherapy.

Hepato-pericardial fistula following radiofrequency ablation (RFA) for liver metastasis: a case report and review of the literature

Recent large-scale studies have demonstrated the efficiency and safety of radiofrequency ablation (RFA) for unresectable hepatic tumors. Nevertheless, severe side effects especially relating to non-target thermal injury have occurred after radiofrequency ablation. We observed the development of a hepato-pericardial fistula leading to pericardial empyema after RFA of a metastatic hepatic lesion. Concerning the genesis of the fistula, development from thermal damages in the diaphragm and pericardium as well as abscess formation in the liver is assumed. Treatment consisted of percutaneous drainage and flushing via remaining hepatic and pericardial catheters. Recovery was achieved conservatively after 2 months. To the best of our knowledge, a hepato-pericardial fistula as a complication of RFA has not been reported so far. The review of the literature revealed several cases of intrahepatic abscess formation after RFA as well as one case of pericardial empyema due to perforation of hepatic amoebic abscess. Two cases of pericardial tamponade after RFA are reported in the literature leading to death. Treatment via percutaneous drainage has been successful in this case and correlates with the successful treatment of abscess formation after RFA of metastatic pancreatic cancer. Other authors suggest pericardectomy or thoracotomy in the treatment of pericardial empyema. The management of hepatic abscess formation subsequent to RFA of metastatic hepatic malignancies is not well described. We regard the percutaneous drainage as treatment of pericardial empyema as well as hepatic abscess as less invasive and sufficient, as demonstrated in this case.

Amoebic Hepatic Abscesses in an HIV-Positive Patient

Herein we report the case of hepatic amoebic abscesses in an HIV-positive Italian seaman with a history of promiscuous heterosexual intercourse. In October 2004, the patient was hospitalized because of fever and recurring abdominal pain. Abdominal ultrasonography revealed six hepatic hypoechoid oval lesions with hyperechoid margins. Stool samples were negative for parasites and bacteria, and serology for Entamoeba histolytica was also negative. Therapy with meropenem plus levofloxacin was initiated. After a partial resolution of clinical symptoms and reduction of three hepatic lesions, the patient was again hospitalized in December 2004, because of recurring intense pain at the right hypochondrium and fever. At this time, one hepatic lesion at the sixth segment was enlarged, two lesions were unchanged, and the remaining three smaller abscesses were resolved. Serum antibodies for E. histolytica and amoebic antigens on the largest abscess drainage were positive; moreover, E. histolytica was also identified on drainage fluid with polymerase chain reaction (PCR). Therapy with metronidazole followed by paromomycin improved both symptoms and radiographic images. This case report suggests that in HIV-infected patients, invasive amoebiasis should be considered and atypical aspects, such as multiple hepatic lesions, delayed positivity of serology for E. histolytica, and possible bacterial superinfection should be evaluated.

Resectability rate of hepatocellular carcinoma in rural southern Africans.

The purpose of this analysis was to ascertain the resectability rate of symptomatic hepatocellular carcinoma in rural southern African black males. All 224 such patients proven to have hepatocellular carcinoma in a single hospital were included in the study. Of 205 patients undergoing a complete diagnostic work-up, 134 [65.3 per cent) were judged on clinical criteria to be inoperable, 23 (11.2 per cent) had pulmonary or osseous metastases, and 38 (18.5 per cent) proved on hepatic imaging and 5 (2.4 per cent) on hepatic arteriography to have an irresectable tumour. Thus, only five (2.4 per cent) of these patients proceeded to laparotomy. Another 7 patients who did not have an arteriogram, 9 with surgical emergencies, and 2 mistakenly believed to have an amoebic hepatic abscess also underwent laparotomy. Only 2 patients (0.9 per cent of 223) proved to have a resectable tumour. The extremely low resectability rate reinforces the urgent need for a surveillance programme to detect early tumours in high-risk members of this population.

Human amoebic hepatic abscess: in situ interactions between trophozoites, macrophages, neutrophils and T cells

Amoebic liver abscesses (ALA) are the most frequent and severe extraintestinal clinical presentations of amoebiasis. During the early establishment of amoebae in the liver parenchyma, as well as during the extension of the tissue necrosis, parasites interact with the parenchymal liver cells and, as a consequence of these interactions, hepatocytes can be destroyed and host immune cells can become activated. However, little is known about the nature of these interactions in the liver or about the factors involved in the local immune response. In this investigation we studied the localization of Entamoeba histolytica trophozoites, TCD4+, TCD8+ cells, CD68+ macrophages and CD15+ neutrophils in human ALA using immunohistochemical techniques. Trophozoites were found close to undamaged hepatocytes in both lysed and non-lysed areas with either sparse or abundant inflammatory infiltrate. CD8+ cells were more abundant than CD4+ T cells. CD 68+ macrophages and CD15+ neutrophils were also detected, suggesting that neutrophils, macrophages and T cells might be related to the local host immune mechanisms in ALA. We also found that E. histolytica possesses proteins recognized by antibodies raised against inducible nitric oxide synthase.

Evaluation of a rapid enzyme immunoassay for diagnosis of hepatic amoebiasis

We compared the capability of rapid enzyme immunoassay (EIA) to detect antiamoebic antibodies during hepatic amoebiasis with those of indirect hemagglutination and latex agglutination. EIA is simple to perform and rapid (20 min) and does not require any special equipment (optical reading is sufficient). EIA of 143 sera (including 43 from patients with proven hepatic amoebic abscess, 33 from patients with other hepatic disorders and/or parasitic infections, and 67 from healthy individuals) yielded a specificity, a sensitivity, and positive and negative predictive values of 100, 93, 100, and 97.1, respectively. This test could thus be considered another valuable tool for the diagnosis of hepatic amoebiasis.

Epidemiological aspects of liver abscesses in children in the Western Cape Province of South Africa.

A high incidence (28 per 100,000 admissions) of liver abscesses is reported in children from the Western Cape Province of South Africa. Of a total of 84 childhood hepatic abscesses over a 10-year period, 51 per cent (43 patients) were primary pyogenic, 30 per cent (25 patients) amoebic, 2 per cent (two patients) Ascaris, and 17 per cent (14 patients) were culture negative. Protein calorie malnutrition was evident in 56 per cent of cases. Amoebic abscesses originated in patients from rural areas, whereas pyogenic abscesses occurred in patients from urban and periurban environments. Staphylococcus aureus was cultured in 85 per cent of pyogenic liver abscesses. Gram negative organisms were identified in four cases of amoebic hepatic abscess where secondary infection occurred. Co-existing parasites of Ascaris lumbricoides and Trichuris trichiura were identified in the stools of 31 per cent of patients. A low (4.8 per cent) mortality is reported for this series.

Ultrasonic features of pyogenic and amoebic hepatic abscesses.

Pyogenic liver abscesses are not infrequent in some developing countries. Amoebic abscesses may also occur in endemic areas and differentiation may be difficult. The ultrasonic data of proven cases of both conditions were compared and we are now more more confident in predicting the aetiology of these lesions.

A comparison between des‐γ‐carboxy prothrombin and α‐fetoprotein as markers of hepatocellular carcinoma in southern African Blacks

Des-gamma-carboxy prothrombin (DCP), a precursor of prothrombin, has been reported recently to be as good a marker, or even better, of hepatocellular carcinoma than alpha-fetoprotein (alpha-FP). The sensitivity, specificity and predictive values of the two markers have been compared in 98 southern African Blacks with hepatocellular carcinoma and in 120 Black controls with various diseases which might be mistaken clinically for this tumour: 32 with hepatic metastases, 33 with amoebic hepatic abscesses, and 55 with chronic hepatic parenchymal disease. DCP levels were measured using a chromogenic assay with Dispholidus typus venom and staphylocoagulase. The agreement between the two methods was excellent (r = 0.995). alpha-FP concentrations were measured by radioimmunoassay. DCP levels were raised in 66 of 98 patients (67.3%) and alpha-FP levels in 82 of 98 patients (83.7%) with hepatocellular carcinoma (P = 0.006). The specificity of DCP was also less than that of alpha-FP, although the difference just failed to reach statistical significance (P = 0.085). The predictive values of both a positive and a negative test for DCP were significantly less than those for alpha-FP (P = 0.047 and 0.048, respectively). When, in an attempt to eliminate false positive results, the diagnostic cut-off level for DCP was increased from 1.5 to 5.0 mu/ml and that of alpha-FP from 20 to 400 ng/ml, the differences between the two markers remained the same. If the two tests were used together, the number of false negative alpha-FP results was reduced from 16.3% to 7.1% and the number of equivocal alpha-FP results was reduced from 11.2% to 5.1%.(ABSTRACT TRUNCATED AT 250 WORDS)