[Mean Platelet Volume in Children with Acute Gastroenteritis Caused by Entamoeba histolytica]. / Entamoeba histolytica'ya Bagli Akut Gastroenteriti Olan Çocuklarda Ortalama Trombosit Hacminin Degerlendirilmesi.

OBJECTIVE: Mean platelet volume (MPV) is a marker of platelet activation, which is a determinant of inflammation. The first aim of the present study was to investigate the MPV levels in children with amebiasis and compare the MPV levels with healthy controls. The second aim of this study was to evaluate the relationship between MPV and other acute phase reactants. METHODS: Seventy six patients with amebic gastroenteritis (mean age 2.64 ± 0.23 years) and 53 healthy controls (mean age 2.35 ± 0.28 years) were enrolled in the study. Entamoeba histolytica was determined in stool using rapid antigen test. RESULTS: Complete blood count and C-reactive protein (CRP) levels were assessed for all children. MPV levels of patients with amebiasis were significantly higher than those of control children (8.79 ± 0.09 vs. 7.87 ± 0.09 fL, p = 0.000). Leukocyte and eosinophil counts, C-reactive protein and creatinine levels of the patients were higher than controls. Leukocyte count was positively correlated with MPV (r = 0.192, p < 0.05), platelet count (r = 0.278, p < 0.01), and CRP level (r = 0.205, p < 0.05). CONCLUSION: In this MPV levels were significantly higher in children with amebiasis compared to controls. MPV can be used as an acute phase reactant in children with Entamoeba histolytica gastroenteritis.

[Amebic colitis and liver abscess complicated by high serum procalcitonin in acute myeloid leukemia].

We present a case of amebic colitis and liver abscess complicated by acute myeloid leukemia (AML) with high serum procalcitonin (PCT). A 61-year-old Japanese man seen at our hospital for severe diarrhea and high fever was found to have multiple ulcers in the transverse and sigmoid colon and rectum by colonoscopy and biopsies were conducted. Immature leukocytes with mild anemia and thrombocytopenia were seen in peripheral blood, necessitating bone marrow aspiration and biopsy that yielded a diagnosis of AML (FAB M4Eo). Serum C-reactive protein and PCT were extremely elevated. Blood cultures for bacteria and fungi were negative. Multiple low-density areas in the liver were found in abdominal computed tomography. Histological colon biopsy findings revealed amebic colitis, strongly suggesting amebic liver abscess. Metronidazole treatment was initiated for amebiasis and subsequent standard chemotherapy for AML was followed after fever was lowered. Hematological and cytogenetic CR was maintained with good clinical condition. Few case reports have been published in Japan to date on amebic colitis and liver abscess complicated by AML and no reports have been made on PCT elevation caused by amebiasis. In conclusion, differential diagnosis of amebiasis is necessary in addition to that of bacterial or fungal infection in serum PCT elevation.

Association between TNF-alpha and Entamoeba histolytica diarrhea.

An association between tumor necrosis factor alpha (TNF-alpha) and Entamoeba histolytica diarrhea was assessed in a cohort of 138 non-related Bangladeshi children who have been prospectively followed since 2001. Peripheral blood mononuclear cells (PBMCs) obtained at study entry were purified, cultured, and stimulated with soluble amebic antigen before cytokine measurement from supernatant. Higher levels of TNF-alpha were associated with increased risk of first (P = 0.01) and recurrent E. histolytica-related diarrheal episodes (P = 0.005). Children who developed E. histolytica diarrhea had significantly higher TNF-alpha protein levels than those who experienced asymptomatic E. histolytica infection (P value = 0.027) or no infection (P value = 0.017). Microarray studies performed using RNA isolated from acute and convalescent whole blood and colon biopsy samples revealed higher but non-significant TNF-alpha messenger RNA (mRNA) levels in subjects with acute E. histolytica diarrhea compared with convalescence. We conclude that there is an association between higher TNF-alpha production and E. histolytica diarrhea.

Serum leptin concentrations in patients with intestinal parasites.

Leptin is a protein hormone controlling food intake and energy expenditure. In all infections including parasitic infections there is loss of appetite and anorexia. The aim of the present study was to clarify the relationship between intestinal parasites and serum leptin concentrations in children and adults. Forty patients with intestinal parasites and 34 healthy subjects took part in this study. Body weight, height and body mass index (BMI) were measured for all patients and controls. Patients were grouped according to age and parasitic infections (Giardia intestinalis, Blastocystis hominis, Enterobius vermicularis, Entamoeba histolytica/Entamoeba dispar, Entamoeba coli). Serum leptin concentrations were detected by immunoenzymometric assay using the Biosource Leptin EASIA kit. Statistical analysis was made by Mann-Whitney-U test using SPSS version 10.0. In children, the serum leptin levels were not statistically significant (patient: 1.49+/-1.97 ng/ml, control: 3.48+/-4.97; p=0.854) But for adults, although the BMI of patients were similar to that of the control group; the leptin levels of patients were low. These levels were not significant (patients: 9.06+/-10.34; controls: 4.7+/-9.02 ng/ml; p=0.271). There was no statistical difference for leptin levels in patient groups, children and adults due to intestinal parasitic infections. Further investigations are needed.

Seroprevalence of Entamoeba histolytica infection in HIV-infected patients in China.

Seroprevalence of Entamoeba histolytica infection in HIV-infected individuals from Shanghai city, Anhui province, and Henan province, China, was examined by enzyme-linked immunosorbent assay using crude antigen and a recombinant surface antigen, C-Igl, of the parasite. In 215 HIV-infected individuals, the positive rates for these antigens were 12.1% and 7.9%, respectively; these rates were significantly higher than the rates of 3.1% and 0.5%, respectively, in 191 patients with gastrointestinal symptoms who were not infected with HIV. There was no significant difference in seropositivity to E. histolytica between men and women. Seropositivity in HIV-infected individuals was higher in patients with a CD4(+) T cell count of < 200/microL. This is the first report showing a higher seroprevalence of E. histolytica infection in HIV-infected patients in China. Our results also suggest that HIV infection is a risk factor for infection with E. histolytica.

HLA characterization in adult asymptomatic cyst passers of Entamoeba histolytica/E. dispar.

The present work aimed at studying the possible association of HLA antigens with Entamoeba histolytica/E. dispar asymptomatic infection in a Mexican mestizo population. A case-control design was selected for evaluation of the role of genetic markers in parasite infection. For this purpose the HLA-A, HLA-B, and HLA-DR profiles of a population of asymptomatic E. histolytica/E. dispar adult cyst passers (cases) and a corresponding nonparasitized adult group (controls) followed for 12 months were identified. Entamoeba species were identified through zymodeme patterns and/or amplification of species-specific DNA sequences. A healthy, nonparasitized group of individuals was included as a control. Our results show that apparently, no specific HLA marker is associated with the asymptomatic cyst passers' condition. These findings have to be added to previous results in which, in contrast to a demonstrated association between HLA-DR3 and amebic liver abscess in Mexican mestizo adults and infants, no significant association with amebic rectocolitis was found.

Absence of an association between enteric parasites in the manifestations and pathogenesis of HIV enteropathy in gay men. The GI/HIV Study Group.

49 gay men confirmed to be infected with the human immunodeficiency virus (HIV) and 9 HIV seronegative gay men participated in a pilot study comparing clinical status and enteric parasite load with gastrointestinal structure, function and symptomatology. Cases included 16/49 (33%) men who were CDC stage II, 7/49 (14%) who were CDC stage III, and 26/49 (53%) who were CDC stage IV. The mean CD4-lymphocyte count was 476 +/- 199 (SD)/microliter. The prevalence of enteric parasitic flora was similar in HIV seropositive patients and controls. Seven cases had enteric infection with pathogenic agents including 3 patients with Entamoeba histolytica, and 4 patients with Giardia lamblia, one of whom also had cryptosporidiosis. Other cases were most frequently colonized with Blastocystis hominis (44%) and Endolimax nana (41%) regardless of the HIV clinical status. HIV seropositive patients with enteric parasitic colonization tended to have lower mean levels of serum IgA than cases without parasites. Duodenal morphometric mucosal changes demonstrated a significant decrease in the mean villous height (p < 0.01) with no elongation of the crypt depth in HIV-infected patients with and without diarrhea compared to controls. Despite gastrointestinal symptoms including diarrhea and weight loss being more prevalent in HIV infected individuals than controls, no correlations were found between the presence of particular enteric parasites, gastrointestinal symptomatology, the clinical HIV status of the CD4-lymphocyte count, the malabsorption of D-xylose or morphometric changes in the duodenum.(ABSTRACT TRUNCATED AT 250 WORDS)

IgA reactivity in patients with intestinal or hepatic amebiasis.

The antigens of E. histolytica recognized by IgA antibodies in sera from patients with either amebic liver abscess or intestinal amebiasis, as well as saliva from the latter, were determined in immunoblots of whole native trophozoite proteins. Results show that sera of patients with amebic liver abscess reacted mainly with amebic proteins of more than 200 kDa, whereas those of individuals with intestinal amebiasis recognized a protein of 145 kDa. The saliva of the latter detected a protein of 210 kDa which is not always seen when using the sera of patients with intestinal or hepatic amebiasis.

Amebiasis in Nicaragua: class specific serum antibody responses.

With the aid of the indirect hemagglutination (IHA) test and IgG ELISA the antibody profile against E. histolytica in León, Nicaragua was investigated in 562 sera from individuals belonging to various age groups. The highest reactivity was invariably recorded in the age group 6-15 years where 48% were seropositive. Several sera reactive by either one of IHA and IgG ELISA were negative by the other test. The main reason for this seems to be reactivity in different Ig classes. Treatment with 2-mercaptoethanol reduced the titre level in 63 of the 66 sera tested. Immunofluorescence using an anti-IgM conjugate showed that 26 of 43 sera contained specific IgM-antibodies, indicating that also unspecific reactions are involved in the IHA test. A comparison was made between class-specific reactivity in three population groups: healthy residents, healthy cyst carriers and patients with recent or acute liver abscess. No significant difference in the prevalence of reactions above the diagnostic significance level was recorded between cyst carriers and healthy residents. However, among the cyst carriers 33% had IgA and/or IgM antibodies but no demonstrable specific IgG. Most patients with recent and all with acute liver abscess reacted significantly above the diagnostic limit in all three tests.

[Fecal and serum anti-amebic antibodies in acute intestinal amebiasis]. / Coproanticuerpos y anticuerpos séricos antiamibianos en la amibiasis intestinal aguda.

Antiamebic antibody titers, were investigated in the feces and sera of 30 adults patients with intestinal amoebiasis, during the first two weeks of disease. Also, 29 control samples of healthy adult subjects were studied. The objective of this study was to determine if the local or systemic IgG, IgM or IgA levels were modified during the early stages of acute intestinal amoebiasis, for this purpose ELISA technique was use. Anti E. histolytica antibody titers in fecal samples of patients were not statistically different from titers detected in control samples, however in both groups IgA and IgM titers were higher than IgG levels. In serum samples IgG antibody titers were 4 fold higher in patients than in control group. With a P less than 0.006. In the case of IgM and IgA differences observed between the two groups studied were not statistically significant. Our results suggest that titration of coproantibodies against E. histolytica have not predictive value for intestinal amoebiasis in areas, were amoebiasis is a endemic disease. On the other hand we observed a discrete increase in IgG levels in the group of patients.

Detection of IgG, IgA, IgM and IgE in antibodies in invasive amoebiasis in endemic areas.

Entamoeba histolytica--specific serum IgG, IgA, IgM and IgE were assayed in cases of amoebiasis in an endemic area. Patient groups consisted of amoebic liver abscess (n = 18), pre abscess hepatic amoebiasis (n = 22) and amoebic colitis (n = 30). Control subjects comprised 26 asymptomatic cyst passers, 13 giardiasis cases, 20 typhoid patients and 24 non amoebic individuals. Serum IgG was assayed by ELISA: using a monoclonal anti IgG beta-galactosidase (IgG beta-gal) conjugate, a polyclonal avidin biotin horse radish peroxidase (AB-HRP) and a polyclonal anti IgG horse radish peroxidase (IgG HRP) conjugate. IgA and IgM were assayed by the beta-gal ELISA and IgE by AB-HRP. Diagnostically significant IgG and IgA while lower IgM and IgE levels were seen in extra intestinal cases. About 40% of suspected pre abscess hepatic amoebiasis cases were confirmed by antibody estimation. All isotype levels in most dysentery cases were in the range of the controls. Inter assay coefficient of variation and assay specificity/sensitivity are also discussed.

Antibodies against Entamoeba histolytica antigens in sera from individuals with amoebiasis of different localization.

The over-all contents and relative component composition of Entamoeba histolytica antigens in abscess fluids and in extracts of cultured amoebae, strain NIH 200, were studied by antigen-catching EIA, counterimmunoelectrophoresis (CIE) and immunoblotting techniques. The antigen contents of liver abscess fluid were determined semiquantitatively by the antigen-catching EIA in four cases. In CIE against a standard "diagnostic" extract of cultured amoebae, sera from cases of acute amoebic liver abscess gave 4-5 precipitation lines while sera from cases of intestinal amoebiasis gave at most 3 lines. In immunoblotting tests with the same antigen, intestinal cases gave blotting bands in the intermediate molecular weight range (25-99 kD) while acute abscess cases, in addition, gave bands in the high (100-175 kD) and low (= less than 25 kD) molecular weight range. These serological differences between clinical forms of amoebiasis were more definite when using amoeba abscess fluid as antigen. Amoeba antigens in high concentrations could be demonstrated in amoeba abscess fluids with all methods employed. In immunoblotting experiments abscess fluids generally gave stronger and more numerous bands with anti-amoeba antibody-containing sera than did the standard "diagnostic" antigen from cultured amoebae. Especially the abscess fluids gave with sera from acute abscess cases a number of prominent bands in the low molecular weight range (less than 25 kD). The experiments in this study were performed with crude amoebic extracts, which contained a multitudes of antigenic components and a still greater diversity of antigenically inert proteins.(ABSTRACT TRUNCATED AT 250 WORDS)

Detection of IgG, IgA, IgM and IgE antibodies in invasive amoebiasis in endemic areas.

Entamoeba histolytica-specific serum IgG, IgA, IgM and IgE antibodies were assayed in cases of amoebiasis in an endemic area. Patient groups consisted of amoebic liver abscess (n = 18), preabscess hepatic amoebiasis (n = 22) and amoebic colitis (n = 30). Control subjects comprised 26 asymptomatic cyst passers, 13 giardiasis cases, 20 typhoid patients and 24 non-amoebic individuals. Serum IgG was assayed by ELISA, using a monoclonal anti IgG beta-galactosidase (IgG beta-gal) conjugate, a polyclonal avidin biotin horse radish peroxidase (AB-HRP), and a polyclonal anti IgG horse radish peroxidase (IgG HRP) conjugate. IgA and IgM were assayed by the beta-gal ELISA and IgE by AB-HRP. Diagnostically significant IgG and IgA while lower IgM and IgE antibody levels were seen in extraintestinal cases. About 40% of suspected pre-abscess hepatic amoebiasis cases were confirmed by antibody estimation. All isotype levels in most dysentery cases were in the range of the controls.

Immunodiagnosis of amoebiasis.

Serological studies were done on 127 cases using three different techniques namely indirect haemagglutination (IHA), indirect fluorescent antibody test (IFT) and counter immunoelectrophoresis (CIEP) to detect antiamoebic antibodies. All amoebic liver abscess cases showed significant titre of antibodies by all the three tests used. In the group of patients suffering from amoebic pathology of liver, 90.47 per cent were positive by IHA, 100 per cent by IFT and 85.71 per cent by CIEP respectively. Among amoebic dysentry and amoebic colitis cases 81.81 per cent and 80.64 per cent respectively were positive by IHA. The corresponding figures for IFT were 100 per cent and 74.19 per cent and for CIEP 90.90 per cent and 64.51 per cent respectively. Follow up study showed no significant fall in antibody titre in nine cases studied upto 10 weeks after treatment. Amoebic antigen could be detected in pus from all the nine cases with amoebic liver abscess by CIEP test.