The epidemiology of schistosomiasis in Egypt: Gharbia Governorate.

Health questionnaires and parasitologic examinations of urine and stool were performed upon a stratified random sample of 14,344 individuals from 1,952 households in 34 rural communities in Gharbia Governorate of Egypt to investigate the prevalence of, risk factors for, and changing pattern of infection with Schistosoma sp. A subset, every fifth household, of 1,973 subjects had physical and ultrasound examinations to investigate prevalence of and risk factors for morbidity. Community prevalence of Schistosoma mansoni ranged from 17.9% to 79.5% and averaged 37.7%. The geometric mean egg count (GMEC) was 78.9 eggs/gram of feces. The prevalence and intensity of infection was 40-50% and 70-100 eggs/gram of feces in those > or =10 years of age. Schistosoma haematobium was detected in 5 of the 34 communities. The maximum infection rate was 2.8% and mean GMEC in the five communities was 2.1/10 ml of urine. The overall prevalence of S. haematobium in the governorate was 0.3%. Risk factors for infection with S. mansoni were male gender, an age >10 years, living in smaller communities, exposures to canal water, prior therapy for schistosomiasis, or blood in the stool (in children only). Morbidity detected by physical examination or ultrasonography did not correlate with S. mansoni infection in individuals with the exception of periportal fibrosis (PPF, odds ratio [OR] = 1.25). Periportal fibrosis was detected in more than half of the subjects by ultrasonography; 5.3% had grade II lesions and 1.0% had the most severe grade III changes. Risk factors for morbidity as manifested by ultrasonographically detected PPF were similar to those for infection. Periportal fibrosis had a negative relationship with abdominal pain (OR = 0.45) and hepatomegaly detected by physical examination and ultrasonography (ORs = 0.72 and 0.68), but it was associated with splenomegaly (ORs = 4.14 and 3.55). The prevalence of PPF, hepatomegaly, and splenomegaly increased with age. There was no relationship between community burden of schistosomiasis mansoni and any measurements of morbidity with the exception of splenomegaly detected by physical examination (r = 0.40). Schistosoma mansoni has almost completely replaced S. haematobium in Gharbia, which has a high prevalence and moderate intensity of S. mansoni infection. Periportal fibrosis was detected by ultrasonography in more than half of the subjects, and 1 in 16 had grade II and III lesions. The only relationship between PPF and other morbidity findings was its positive relationship with splenomegaly and negative association with hepatomegaly. Hepatic morbidity is common in communities in Gharbia but the role of schistosomiasis mansoni in this is uncertain.

Humoral and mucosal IgA antibody response to a recombinant 52-kDa cysteine-rich portion of the Entamoeba histolytica galactose-inhibitable lectin correlates with detection of native 170-kDa lectin antigen in serum of patients with amebic colitis.

Humoral and mucosal IgA responses to a recombinant cysteine-rich portion (designated LC3) of the Entamoeba histolytica galactose-inhibitable lectin's 170-kDa subunit were determined in patients with amebic colitis. All patients had 170-kDa amebic antigen in serum, compared with 1 of 50 cyst passers and 1 of 31 controls (P < .01). Seven days after treatment, serum and fecal 170-kDa antigen became undetectable in 12 of the 13 patients (P < .001). Serum anti-LC3 IgA was found in 83.8% of colitis patients, compared with 2% of controls and 12% of asymptomatic cyst passers (P < .001). Salivary and fecal anti-LC3 IgA levels were higher in patients than in cyst passers (P < .001). In conclusion, in amebic colitis, development of humoral and mucosal IgA responses to the recombinant LC3-encoded protein correlates with detection of amebic 170-kDa antigen in serum and feces.

Prevalence and morbidity of schistosomiasis among rural fishermen at two Egyptian villages (Gharbia Governorate).

210 fishermen and 210 farmers from two Egyptian villages (Gharbia Governorate) were selected. Their main clinical manifestations were terminal haematuria in 17.1% and 10%, dysuria in 16.7% and 6.7%, renal colic in 13.3% and 2.4%, dysentery in 10.5% and 3.8%, bloody stool in 8.1% and 2.9%, pallor in 28.8% and 15.2%, hepatomegaly in 10.5% and 4.3% and splenomegaly in 8.6% and 3.8% in fishermen and farmers respectively with significant values among fishermen when compared with farmers. Abdominal ultrasonography of fishermen showed higher morbidity rates than farmers as regards hepatosplenomegaly, grades of periportal fibrosis, portal vein diameter, stones in Kidneys and urinary bladder as well as calcification of urinary bladder. S. mansoni prevalence was 72.4% in fishermen and 4.57% in farmers with highly significant value in fishermen when compared with farmers (P < 0.01). Geometric egg count (gm/stool) was 430 +/- 259 and 236 +/- 161 in fishermen and farmers respectively with highly significant difference (P < 0.001). All urine samples were negative for S. haematobium. The socioeconomic status of all individuals showed no significant difference between the two groups. It was concluded that fishermen had a higher S. mansoni prevalence, infection intensity and morbidity than farmers. This may be due to more water contact activities. A snail population survey of the river and main canals was recommended.

Differentiation of pathogenic Entamoeba histolytica infections from nonpathogenic infections by detection of galactose-inhibitable adherence protein antigen in sera and feces.

We determined whether epitope-specific monoclonal antibodies to the galactose-inhibitable adherence protein (GIAP) of Entamoeba histolytica could be used in an enzyme-linked immunosorbent assay (ELISA) to detect antigen in serum and feces and differentiate between nonpathogenic zymodemes and the potentially invasive pathogenic organisms that require treatment. Overall, 57% of subjects from Cairo, Egypt, with symptomatic intestinal amebiasis and 42% with asymptomatic infection possessed GIAP antigen in their sera, whereas 4% of uninfected controls or subjects with other parasitic infections possessed GIAP antigen in their sera (P < 0.001). In subjects from Durban, South Africa, only 6% of uninfected controls or those with nonpathogenic E. histolytica infection were positive for GIAP in serum, whereas 3 of 4 with asymptomatic pathogenic intestinal infection and 75% with amebic liver abscess were positive for GIAP in serum. Fifteen stool samples from patients with intestinal amebiasis were available for study; all had a positive ELISA result for fecal GIAP antigen. Epitope-specific monoclonal antibodies identified 8 of 15 subjects with fecal antigen from pathogenic strains. Seven of those eight subjects had adherence protein antigen in their sera, whereas none of seven with apparent nonpathogenic E. histolytica infection had adherence protein antigen in their sera. In summary, we were able to detect E. histolytica adherence protein antigen directly in serum and fecal samples by ELISA. The presence of amebic antigen in serum demonstrated 94% specificity for pathogenic E. histolytica infection, and amebic antigen is present during asymptomatic intestinal infection. In conjunction with antibody detection, this method should be very useful in the diagnosis and management of intestinal amebiasis.

Delta virus versus HBsAg in chronic active hepatitis and their relation to clinical, laboratory, and morbidity findings in bilharzial and non-bilharzial patients.

This work was done to study the effect of delta virus and HBV infection, as two aetiological factors on clinical presentation, biochemical liver functions and prognosis of chronic active hepatitis (CAH) in schistosomiasis infected and non-infected patients. 66.7% of the patients were carriers for HBsAg, among them 41.7% were infected with delta virus. It was evident that the clinical presentation of the patients with positive serological markers of HBV and HDV demonstrated advancing liver disease than in the other studied groups. Moreover, the biochemical liver profile was significantly affected when the triad of chronic HBV, delta virus and schistosomiasis infection was present. This could be related to the immunosuppression caused by schistosomal infection. Furthermore, mortality rate was significantly higher in schistosomiasis infected individuals.

Lactase deficiency in patients with intestinal schistosomiasis.

Sixty patients having schistosomiasis mansoni infection were studied for lactase deficiency by different methods including lactase assay in intestinal biopsies. Thirty patients suffering from simple intestinal (Group I) and 30 patients suffering from hepatointestinal (Group II) schistosomiasis were compared to 60 controls (Group III). Lactase deficiency was evaluated by symptoms of lactose intolerance, stool pH and osmolarity, oral lactose tolerance test (OLLT), oral lactose hydrogen breath test (OLHBT) and lactase activity (LA) in small intestinal biopsies. OLTT showed intolerance in 36.7% of Group I and 40% of Group II compared to 23.3% of the controls. OLHBT showed intolerance in 26.7%, 30% and 18% for the three groups respectively, indicating a significance in Groups I and II. Abdominal symptoms of hypolactasia had higher scores in the patient groups compared to the controls, and was even higher in Group I than Group II. The mean lactase activity measured by micromol/gm wet wt/min was not statistically higher in Group I but higher in Group II than the controls. No correlation was found between lactase activity in the mucosa and the symptoms of hypolactasia in Group I. Hence, other factors in intestinal schistosomiasis may affect lactose hydrolysis. The study showed also that OLHBT is the most sensitive, specific and efficient among the non-invasive tests.

Use of an enzyme-linked immunosorbent assay to detect anti-adherence protein antibodies in sera of patients with invasive amebiasis in Cairo, Egypt.

We used enzyme-linked immunosorbent assay (ELISA) to detect IgG antibodies to the Entamoeba histolytica galactose-inhibitable adherence protein in the sera of 50 uninfected controls, 50 cases with asymptomatic cyst passage, 100 patients with amebic colitis, and six patients with amebic liver abscess from Cairo, Egypt, and in 50 healthy controls from the United States. When the mean + 3 SD value above that of the controls from the United States was used as a criterion for a positive ELISA result, 100% of those with invasive amebiasis, 80% of those with asymptomatic infection, and 64% of the Egyptian controls had anti-adherence protein antibodies. However, when the mean + 2 SD value of Egyptian control sera (optical density = 0.094) was used as the criterion for positivity, 33 (89%) of 37 sera from individuals with invasive amebiasis having symptoms for at least one week were antibody positive, in contrast to only 12% of asymptomatic cyst passers (P < 0.01). In a highly endemic area such as Cairo, Egypt, detection of serum anti-adherence protein antibodies by ELISA may have greatest diagnostic use in patients with symptomatic invasive amebiasis of greater than one week duration.

Assessment of left ventricular function by Doppler echocardiography in Egyptian bilharzial patients with or without pulmonary hypertension.

Forty-eight Egyptian bilharzial patients were selected for this study. Forty males and eight females. Their ages ranged from 12-60 years. All had hepatosplenomegaly with or without cardiopulmonary schistosomiasis. Also a group of ten subjects was chosen as a control group. After full clinical, laboratory and radiological examinations our subjects were subjected to: right cardiac catheterization, M-mode, two-dimensional as well as Doppler echocardiography. We found that the left ventricular geometry was distorted from its circular configuration as a result of right ventricular pressure overload as measured by the eccentricity index in bilharzial pulmonary hypertension. Also there were significant impairment of all Doppler echocardiographic parameters in those patients except time to E-peak (early diastolic flow velocity) and acceleration time of aortic flow (cm/sec2).

Profile of portal hypertension in hepatosplenic schistosomiasis.

Intrasplenic pressure changes versus ova count in stool of schistosomal portal hypertension in cases of bilharzial hepatic fibrosis were studied before and after 40 mg/kg body weight praziquantel therapy. Praziquantel acts on the vascular level in which it decreases the portal hypertension caused by bilharziasis as detected by decreased size of portal and splenic veins diameter as well as a significant decrease of portal pressure by the decrease of intrasplenic pressure (P less than 0.05). On the other hand, praziquantel decrease bilharzial stool egg count after 3 months of therapy (P less than 0.05).

Study of some aspects of cell mediated immune response in bilharzial children on a field level.

S. mansoni patients with active intestinal mansoniasis with or without hepatosplenomegaly were divided into 3 groups. The first was treated by praziquantel therapeutic course, second by an initial full dose of praziquantel to be followed by suppressive doses, and third received initial loading praziquantel dose and followed by the suppressive dose at monthly intervals. School children infected with S. haematobium were divided into 5 groups: The first received oral metrifonate therapeutic course followed by its prophylactic course monthly, second with full dose of oral praziquantel, third with metrifonate orally every month, fourth half dose of praziquantel orally every month, fifth received oral metrifonate curative course every 2 weeks for 3 doses every 6 months, repetition of such therapy was carried out 6 monthly for non-cured cases. Non-bilharzial children were studied and divided into six groups. The first was given an oral monthly praziquantel prophylactic dose. The second received the same prophylactic praziquantel doses given at 3-monthly intervals. The third was given an oral placebo in the form of vitamin B complex tablets at 3-monthly intervals. The fourth received oral monthly therapeutic dose of metrifonate. The fifth was given oral monthly prophylactic doses of praziquantel. The sixth was given oral placebo in the form of 2 vitamin B-complex tablets monthly. For every individual whole blood leucocyte % phagocytosis and tuberculin test were performed. In cases infected with S. mansoni the mean percent phagocytosis was only markedly reduced in hepatosplenic cases of groups P-1, P-2 and P-3 during praziquantel treatment. Tuberculin reactivity was not changed following such therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

Association of reduced antibody response to "SMW68" (an affinity purified schistosomal antigen) with hepatosplenomegaly in Egyptian schoolchildren infected with Schistosoma mansoni.

Studies of the pathogenesis of schistosomal infections have revealed that the occurrence of disease is so strongly related to host responses to parasite products, that schistosomiasis can be considered as an immunological disease. Further, numerous genetic and environmental factors may modify the host resistance or susceptibility to disease. To test whether hepatosplenic patients manifest different immune capabilities, and the effects of intensity of infection on immune responses; we evaluated anti-SMW68 and anti-crude antigens (SWAP & SEA) antibody levels in 100 children aged 9-15, having light and moderate S. mansoni infection (80-360 eggs/gm of stool). In this group, anti-SMW67 antibody levels (determined by ELISA) were significantly higher in those with lower levels of infection (P less than 0.001). Furthermore, the hepatosplenic patients showed a lower anti-SMW68 antibody levels than those with intestinal schistosomiasis. (P less than 0.05). We conclude that the worm burden and so the resultant morbidity may be influenced by the immune capabilities of the host. Whether enhanced antibody response to SMW68 represents acquired protective humoral immunity remains to be determined.

Side effects of praziquantel in bilharzial children on a field level.

For studying the side effects of praziquantel in children with active intestinal bilharziasis 6 groups of children were followed: group P-1 (active intestinal bilharziasis +/- hepatosplenomegaly). They were treated with praziquantel (40 mg/Kg b.w. orally every 6 months). group P-2 (children with active mansoniasis +/- hepatosplenomegaly. They were treated with an initial full dose of praziquantel (40 mg/kg) to be followed by suppressive dose (20 mg/kg) at 3-months intervals, group P-3 (school children with active mansoniasis +/- hepatosplenomegaly). Initial loading praziquantel dose was followed by suppressive dose at monthly intervals, group N-1 (non-bilharzial children given an oral monthly praziquantel prophylactic dose of 20 mg/kg, group N-2 (non-bilharzial children given an oral 3-monthly praziquantel prophylactic dose of 20 mg/kg), group N-3 (non-bilharzial school children given an oral placebo in the form of vitamin B complex tablets at 3-monthly intervals. Surveillance for praziquantel adverse reactions for all these groups was done. It revealed that the adverse reactions were nausea, vomiting, abdominal colic, diarrhea, dizziness, headache and pyrexia. These were noticed more after full therapeutic praziquantel dose than half doses (subcurative or prophylactic) & among bilharzial children than non-bilharzial cases. As regards school children with active urinary hematobiasis 3 groups were followed: Group 1 (school children with active urinary hematobiasis treated with praziquantel orally 40 mg/kg b.w. every 6 months). Group 2 (non-bilharzial school children given oral monthly prophylactic dose of 20 mg/kg b.w. praziquantel). Group 3 (non-bilharzial school children given oral placebo in the form of two vitamin B-complex tablets monthly).(ABSTRACT TRUNCATED AT 250 WORDS)

Studies on liver profile after prolonged praziquantel courses for schistosomiasis mansoni in Egyptian children on a field level.

The effect of prolonged praziquantel courses on the clinical, sonographic and functional aspects of the liver in bilharzial and nonbilharzial school-children on village level was investigated in this study. Bilharzial--positive school--children were divided into three groups according to Praziquantel regimes. Each case received an initial dose of 40 mg/Kg. PZQ. Subsequently the first group received 6-monthly full dose, the second group received 3-monthly half doses and the third group received monthly half doses. Another 3 groups of bilharzial negative children were used as a control receiving oral vitamin B complex as placebo. Clinico-parasitological and sonographic examinations as well as liver function tests were done before and after drug administration. It was concluded according to our results that healing of hepatic pathology was slower than parasitological cure. Moreover complete reversibility of hepatic size required frequent praziquantel doses (from 3 to 7). Hepatic healing is dose related. Less doses are required for parasitological cure.

Morbidity of schistosomiasis hematobia in an Egyptian village.

One hundred and fifty patients with active Schistosomiasis haematobium were chosen from Azizia village an endemic area. 50 healthy controls of the same age and sex groups were chosen. Patients were subjected to complete clinical and laboratory examination. Praziquantel orally in a dose of 40 mg/kg was given to each individual and its therapeutic efficacy was assessed by comparing the results of the previous investigations before and 3 months after treatment. The highest infection intensity was noticed in the small age group (A). There was a statistically significant increase of haematuria in this group, dysunia in middle age (B) and increase frequency of micturition & suprapubic tenderness in older age group (C). Ultrasonography showed partial calcification of bladder in 18% of cases in group A, 28% of cases in group B; in group C the percentage was 32% with 14% hydronephrosis, bladder mass 2%, stone bladder & ureter 6%. After praziquantel therapy there was a statistically significant (1) Reduction in haematuria, dysuria increase frequency and suprapubic tenderness (Z less than 1.96). (2) reduction of mean egg count in urine (3) significant improvement of Hb% (4) bladder calcifications showed partial improvement.

Ultrasonographic profile of the liver and caliber of portal vein after oral antibilharzial drugs.

This study was done on 45 patients with bilharzial hepatosplenomegaly and active bilharzial infection classified into 3 groups. The first group was given oral oxamniquine 2nd group was given oral praziquantel, the third group was left as control. It was proved that praziquantel gave a remarkable decrease in portal vein diameter and regression of the size of enlarged liver and spleen but oxaminiquine had no significant effect on the portal vein diameter and liver profile.