The epidemiology of schistosomiasis in Egypt: methods, training, and quality control of clinical and ultrasound examinations.

Morbidity due to schistosomiasis was evaluated in a subpopulation of 14,000 of the randomized sample in the Epidemiology 1, 2, 3 Project. It was measured by using a standardized questionnaire for obtaining medical history and symptoms and by performing standardized physical and ultrasound examinations. Reported herein are descriptions of the methods and training and quality control efforts made to insure that the morbidity data was reliable and consistent when collected by 7 different teams in 9 different governorates.

The epidemiology of schistosomiasis in Egypt: Menofia Governorate.

Health questionnaires and parasitologic examinations of urine and stool were performed upon a stratified random sample of 10,899 individuals from 1,537 households in 27 rural communities in Menofia Governorate in Egypt in 1992 to investigate the prevalence of, risk factors for, and changing pattern of infection with Schistosoma sp. in the governorate. A subset, every fifth household, or 1,480 subjects, had physical and ultrasound examinations to investigate prevalence of and risk factors for morbidity. The prevalence of S. mansoni ranged from 0.3% to 72.9% and averaged 28.5%. The geometric mean egg count was 81.3 eggs/gram of stool. Age-stratified prevalence and intensity of infection was 30-40% and 60-80 eggs/gram of stool from the age of 10 onward; males had higher infection rates and ova counts than females in all age groups > 10 years old. Schistosoma haematobium was rare, being consequential in only 1 community. Risk factors for S. mansoni infection were male gender; age > 10 years; living in smaller communities; exposures to canal water; history of or treatment for schistosomiasis or blood in the stool; detection of splenomegaly by either physical or ultrasound; and ultrasound-detected periportal fibrosis (PPF). The more severe grades of PPF were rarely (21 of 1,450 examinations) detected. Risk factors for morbidity, i.e., ultrasound-detected PPF, were similar to those for infection. Schistosoma mansoni has almost totally replaced S. haematobium in Menofia. The prevalence of S. mansoni in rural communities remains high and average intensities of infection are moderate. The association of morbidity with schistosomal infection was variable and is obviously markedly influenced by both the frequent use of antischistosomal chemotherapy in communities in Menofia and by the prevalence of complications from chronic viral hepatitis in the population: hepatomegaly did not correlate with infection; PPF and splenomegaly, however, were related to S. mansoni infection in both individuals and communities.

The epidemiology of schistosomiasis in Egypt: Fayoum Governorate.

Health questionnaires and parasitologic examinations of urine and stool were performed upon a stratified random sample of 7,710 individuals from 1,109 households in 21 rural communities in Fayoum Governorate, Egypt in 1992 to investigate the prevalence of, risk factors for, and changing pattern of, infection with Schistosoma sp. in the governorate. A subset, every fifth household, or 1,038 subjects, had physical and ultrasound examinations to investigate prevalence of, and risk factors for, morbidity. The prevalence of S. haematobium ranged from 0% to 27.1% and averaged 13.7%. The geometric mean egg count (GMEC) was 10.0 eggs/10 ml of urine. Age-stratified prevalence and intensity of infection were 18-25% and 10-15 eggs/10 ml of urine in those 5-25 years of age. Schistosoma mansoni were detected in inhabitants of 13 communities, but 78.5% of the infections were focally present in a group of 4 satellite hamlets around a single village. The overall prevalence of S. mansoni in the governorate was 4.3% and the GMEC was 44.0 ova/g of stool. Risk factors for infection with either species were male gender, an age <20 years, living in smaller communities, and exposures to canal water by males. Histories of burning micturation, blood in the urine, or prior schistosomiasis and reagent strip-detected hematuria and proteinuria were risks for S. haematobium, but not for S. mansoni. Both urinary tract and higher grades of hepatic morbidity were rare. Obstructive uropathy was present in 6.3% of the subjects and was more common in males and older people. Ultrasonography-detected bladder lesions were present in 5.2% and correlated with S. haematobium only in younger subjects and in those with hematuria and proteinuria. The prevalences of hepatomegaly, splenomegaly, and periportal fibrosis (PPF) were associated with each other and increased with age and in males. Ultrasonography-detected hepatomegaly and splenomegaly were weakly associated with S. mansoni infections only in children. The prevalence of PPF was greater in the 4 communities with >25% S. mansoni infection rates in comparison with the 17 other villages and ezbas. Transmission of S. mansoni is focally well established in Fayoum, which also has the highest prevalence of S. haematobium in the governorates surveyed by the Epidemiology 1, 2, 3 Project. However, both urinary tract and hepatic morbidity are relatively rare in the governorate. This probably results from the long-standing schistosomiasis control program in Fayoum, which suppressed intensity more than prevalence of infection, leading to less community morbidity.

Capillaria philippinensis: an emerging parasite causing severe diarrhoea in Egypt.

Four cases with Capillaria philippinensis have been reported from Egypt during 1989-1992. The authors report here four other cases of severe diarrhoea caused by this parasite. A male and three female patients aged 12-45 years presented with severe diarrhoea of 1-7 months duration associated with vomiting and central abdominal colics. Stools were yellowish or greenish and voluminous. Anorexia was profound with loss of weight. Bilateral painless ankle oedema developed early in the course of the disease and two cases had ascites and bilateral pleural effusion at presentation. There was hyponatraemia, hypocalcaemia and marked hypokalaemia and hypoalbulinaemia. Small bowel series showed a rapid transit time in 3 cases and malabsorption pattern in one. Duodenal biopsies showed non-specific chronic inflammation while jejunal biopsies from one case revealed grade II villous atrophy with moderate cellular infiltration of lamina propria. The infection was diagnosed by finding the eggs, larvae and adult worms of C. philippinensis in stool. Patients were treated with mebendazole 400 mg/day in two divided doses for 28 days in addition to high protein diet and correction of electrolyte disturbance. Vomiting stopped on the second day of treatment, appetite improved and diarrhoea regressed by the fourth day. Unfortunately, one case died two days after admission due to marked hypokalaemia. Clinico-pathological and epidemiological aspects of this infection in Egypt are discussed.

Ultrasonographic prediction of esophageal varices in Schistosomiasis mansoni.

Bleeding from esophageal varices is a common and serious problem in Schistosomiasis mansoni. A simple and accurate method of detection would facilitate measurement of individual and community morbidity and allow institution of preventive measures. An ultrasonographic scoring system grading periportal fibrosis, portal vein diameter, spleen size, and portasystemic anastomoses was evaluated as a predictor of esophageal varices and a past history of upper gastrointestinal hemorrhage in 43 patients with hepatosplenic schistosomiasis. Ultrasonographic variceal score correlated (r = 0.86, p < 0.001) with the endoscopic variceal grade. Patients with a sonographic score of 5 or greater were highly likely (21 of 23) to have varices of grade II or greater (sensitivity, 91.3%; specificity, 94.7%). Only those with sonographic scores of 5 or greater (15 of 23) had bled from esophageal varices. The ultrasonographic score provided a simple, inexpensive, accurate, and noninvasive means of screening individuals with hepatosplenic schistosomiasis for esophageal varices, and correlated strongly with prior gastrointestinal hemorrhage. It is not known whether a similar score would be useful in hepatic cirrhosis.

Grading of hepatic schistosomiasis by the use of ultrasonography.

Forty-three subjects with pure hepatic schistosomiasis having ultrasonographic assessment of periportal fibrosis were grouped according to the thickness of their portal tracts: grade I = 3-5 mm, grade II = greater than 5-7 mm, and grade III = greater than 7 mm. A history of hematemesis, blood transfusion, sclerotherapy, and lower limb edema correlated with the ultrasonographic grade of periportal fibrosis. With increasing grade, the average liver size was smaller and the average spleen size was larger, as determined by physical examination and by ultrasonography. Abnormalities in serum enzyme levels were more frequent in those with thicker portal tracts. Greater diameters of the portal and splenic veins and ultrasonographically detectable collateral blood vessels were associated with increasing thickness of portal tracts. The grade of endoscopically determined esophageal varices was highly correlated with the grade of periportal fibrosis. We concluded that this method of grading accurately reflects the hemodynamic changes and provides a good estimate of the clinical status of patients who have periportal fibrosis due to schistosomiasis mansoni. Where available, it should replace clinical grading based upon the liver and spleen size as detected by physical examination.