Schistosomiasis haematobia: histopathological course determined by cystoscopy in a patient in whom praziquantel treatment failed / Esquistossomíase hematóbica: seguimento histopatológico determinado por cistoscopia em um paciente com falha terapêutica ao praziquantel

Schistosomiasis haematobia or urinary schistosomiasis is one of the main public health problems in Africa and the Middle East. A single dose of 40 mg praziquantel per kg body weight continues to be the treatment of choice for this infection. The aims of this follow-up were to study the post-treatment course of a patient infected with S. haematobium and not submitted to re-exposure, and to identify complications of the disease and/or therapeutic failure after praziquantel treatment by histopathological analysis. Treatments were repeated under medical supervision to ensure the correct use of the drug. In view of the suspicion of lesions in cystoscopy, the patient was submitted to bladder biopsy. The histopathological characteristics observed in biopsies obtained, after each treatment, indicated viability of parasite eggs and activity of granulomas.

A Esquistossomíase Hematóbica ou Esquistossomíase Urinária é um dos principais problemas de Saúde Pública na África e no Oriente Médio. Uma única dose de praziquantel 40 mg/kg de peso, continua sendo o tratamento de escolha para esta infecção. Os objetivos deste seguimento foram: avaliar o período pós-tratamento de um paciente infectado com Schistosoma haematobium e não submetido à re-exposição e, identificar as complicações da doença e/ou falha terapêutica, após o tratamento com praziquantel, por análise histopatológica de material obtido por biópsia vesical. O tratamento foi repetido sob supervisão médica para assegurar o uso correto do medicamento. Na presença de lesões suspeitas a cistoscopia, o paciente foi submetido a biópsia vesical. As características histopatológicas observadas nos materiais obtidos por biópsia, após cada tratamento, indicaram viabilidade de ovos e atividade dos granulomas.

Anti-malaria humoral responses in children exposed to Plasmodium falciparum and Schistosoma haematobium

Antibody responses directed against the Plasmodium falciparum antigens, total extract, anti-merozoite surface protein-3 (MSP3b) and glutamate-rich protein (Glurp-R0) were studied in 42 children exposed to both Schistosoma haematobium and P. falciparum infections. The association between levels of the anti-malaria IgG subclasses and IgM with host age, sex, schistosome infection intensity and schistosome specific antibodies was studied before chemotherapeutic treatment of schistosome infections. This showed a significant negative association between schistosome infection intensity and levels of IgG1, IgG3, and IgG4 directed against malaria total extract antigen, and a positive association between levels of anti-schistosome soluble egg antigen IgG2, IgG3, and IgG4 and levels of the same subclasses directed against malaria total extract antigens. The effect of treating schistosome infections with praziquantel on malaria specific responses was also studied. This treatment resulted in increases in significant IgG4 levels against MSP3b and IgM against Glurp R0. Treatment also resulted in a significant decrease in IgG4 levels against Glurp R0. Host age, sex or pre-treatment infection intensity was not associated with the magnitude of change in the two IgG4 responses while males showed a significantly higher increase in levels of IgM. The results suggest cross reactivity between schistosome and malaria antigens in this population.

Long-term outcomes of school-based treatment for control of urinary schistosomiasis: a review of experience in Coast Province, Kenya

Urinary schistosomiasis remains a significant burden for Africa and the Middle East. The success of population-based control programs will depend on their impact, over many years, on Schistosoma haematobium reinfection and associated disease. In a multi-year (1984-1992) control program in Kenya, we examined risk for S. haematobium reinfection and late disease during and after annual school-based treatment. In this setting, long-term risk of new infection was independently associated with location, age, hematuria, and incomplete treatment, but not with sex or frequency of water contact. Thus, very local environmental features and age-related factors played an important role in S. haematobium transmission, such that population-based control programs should optimally tailor their efforts to local conditions on a village-by-village basis. In 2001-2002, the late benefits of earlier participation in school-based antischistosomal therapy were estimated in a cohort of formerly-treated adult residents compared to never-treated adults from the same villages. Among age-matched subjects, current infection prevalence was lower among those who had received remote therapy. In addition, prevalence of bladder abnormality was lower in the treated group, who were free of severe bladder disease. Treatment of affected adults resulted in rapid resolution of infection and any detectable bladder abnormalities. We conclude that continued treatment into adulthood, as well as efforts at long-term prevention of infection (transmission control) are necessary to achieve optimal morbidity control in affected communities.

Clinical and laboratorial evaluation of urinary schistosomiasis in Brazilians after staying in Mozambique

Nós examinamos 87 brasileiros de um grupo de 132 que, entre julho e novembro de 1994, participaram de um missão de paz em Moçambique. Eles serviram em uma área endêmica de esquistossomose haematóbica e nadaram no rio Licungo em períodos de lazer. A idade aritmética deles era 31 anos e todos eram do gênero masculino. O exame de urina revelou que 30 (34,5%) eliminavam ovos de S. haematobium e 55 (63,2%) tinham sorologia positiva pelo teste enzyme-linked immunoelectrotransfer blot com antígeno microsomal purificado de vermes adultos de S. haematobium. Eosinofilia foi encontrada em 30 (34,5%), haematuria em 26(29,9%), disúria em 32(36,8%) e dor lombar em 36(41,4%). Todos que eliminavam ovos pela urina tiveram sorologia positiva. Entre os 25 pacientes com sorologia positiva e sem ovos de S. haematobium no exame de urina, 13 eram sintomáticos e 12 assintomáticos. O tratamento pelo Prazinquantel nos 30 pacientes com urina positiva para ovos de S. haematobium apresentou 70% de cura parasitológica.

Cystoscopy in the diagnosis and follow-up of urinary schistosomiasis in Brazilian soldiers returning from Mozambique, Africa

A avaliação de esquistossomose urinária em indivíduos procedentes de áreas endêmicas, freqüentemente requer recursos diagnósticos não usados nas áreas de exposição, para determinar as complicações ou estabelecer um critério de cura mais preciso. A cistoscopia e o exame de urina de 24 horas foram realizados, após tratamentos com praziquantel na dose de 40 mg/kg de peso, dose única, em 25 militares brasileiros que participaram de uma Missão de Paz pela ONU em Moçambique no ano de 1994. A idade média dos indivíduos foi de 29 anos e todos apresentavam exame parasitológico de urina positivo. As alterações detectadas pela cistoscopia foram hiperemia e granulomas na submucosa vesical em 59.1% dos indivíduos e somente granulomas em 40.9%. A biópsia vesical revelou granulomas em todos os pacientes e ovos viáveis em 77.3%, mesmo após um período durante o qual os pacientes não mais eliminavam ovos pela urina. Após o tratamento, a cistoscopia seguida por biópsia e avaliação histopatológica, realizada em áreas onde a evolução da doença pode ser monitorada melhor, demonstrou ser um critério mais seguro de cura parasitológica.

Therapeutic failure of praziquantel in the treatment of Schistosoma haematobium infection in Brazilians returning from Africa

Several cases of therapeutic failure of praziquantel used for the treatment of urinary schistosomiasis have been reported. Alternative drugs, like niridazol and metrifonate, have shown a lower therapeutic effect and more side effects than praziquantel. Twenty-six Brazilian military men (median age of 29 years) with a positive urine parasitological exam who were part of a United Nation peace mission in Mozambique in 1994 were treated with 40 mg/kg body weight praziquantel, single dose. They swimmed in Licungo river (Mocuba city, Mozambique) during the weekends. After this, they presented haematuria, dysuria, polakiuria, and lumbar pain. Control cystoscopy examinations carried out between 6 and 24 months after each treatment (including two additional treatments at a minimum interval of 6 months) revealed the presence of viable eggs. Granulomas in the vesical submucosa were observed in 46.2 percent (12/26) of the individuals. A vesical biopsy confirmed the presence of granulomas in all of these patients and the presence of viable eggs in 34.3 percent (9/26) of individuals who no longer excreted eggs in urine. The eggs filled with miracidia showed characteristics of viability. Histopathological examination using different strains demonstrated therapeutic failure and the need for repeated treatment. In this study, we demonstrated a low efficacy of praziquantel in the treatment of schistosomiasis haematobia, and the necessity of the urinary bladder biopsy as criterion of cure.

Combined Schistosoma mansoni and Schistosoma haematobium infection

An imported case of combined Schistosoma mansoni and Schistosoma haematobium infection occurring in Liberia is reported. A young girl of 15 years, who had recently returned from the neighbouring country of Guinea, presented with 04 months history of passing blood in stools. Schistosoma mansoni ova were found in stool and Schistosoma haematobium ova in urine. She was treated with tablet praziquantel. She became symptom-free in four weeks and the number of ova passed in stool and urine decreased

The impact of repeated treatment with praziquantel of schistosomiasis in children under six years of age living in an endemic area for Schistosoma haematobium infection

Praziquantel was given every eight weeks for two years to children aged under six years of age, living in a Schistosoma haematobium endemic area. Infection with S. haematobium and haematuria were examined in urine and antibody profiles (IgA, IgE, IgM, IgG1, IgG2, IgG3, and IgG4) against S. haematobium adult worm and egg antigens were determined from sera collected before each treatment. Chemotherapy reduced infection prevalence and mean intensity from 51.8 percent and 110 eggs per 10 ml urine, respectively, before starting re-treatment programme to very low levels thereafter. Praziquantel is not accumulated after periodic administration in children. Immunoglobulin levels change during the course of treatment with a shift towards 'protective' mechanisms. The significant changes noted in some individuals were the drop in 'blocking' IgG2 and IgG4 whereas the 'protecting' IgA and IgG1 levels increased. The antibody profiles in the rest of the children remained generally unchanged throughout the study and no haematuria was observed after the second treatment. The removal of worms before production of large number of eggs, prevented the children from developing morbidity

T cell clones from Schistosoma haematobium infected and exposed individuals lacking distinct cytokine profiles for Th1/Th2 polarisation

T cell clones were derived from peripheral blood mononuclear cells of Schistosoma haematobium infected and uninfected individuals living in an endemic area. The clones were stimulated with S. haematobium worm and egg antigens and purified protein derivative. Attempts were made to classify the T cell clones according to production of the cytokines IL-4, IL-5 and IFN-gamma. All the T cell clones derived were observed to produce cytokines used as markers for the classification of Th1/Th2 subsets. However, the 'signature' cytokines marking each subset were produced at different levels. The classification depended on the dominating cytokine type, which was having either Th0/1 or Th0/2 subsets. The results indicated that no distinct cytokine profiles for polarisation of Th1/Th2 subsets were detected in these S. haematobium infected humans. The balance in the profiles of cytokines marking each subset were related to infection and re-infection status after treatment with praziquantel. In the present study, as judged by the changes in infection status with time, the T cell responses appeared to be less stable and more dynamic, suggesting that small quantitative changes in the balance of the cytokines response could result in either susceptibility or resistant to S. haematobium infection

Seasonally as a determinant of the efficacy of praziquantel in population based chemotherapy: lessons from the practice

During October-November 1991, 1356 male farmers, 18-40 years old from a village in Fayoum Governorate, Egypt, were examined for Schistosoma hematobium infection. The prevalence of infection was 22.2%. Infected farmers were treated immediately with Praziquantel at the recommended dose of 40 mg/kg body weight in a single, oral dose. 12 weeks after treatment, 86/262 infected farmers were negative for S. hematobium eggs in urine. In another study conducted in a satellite village in the Nile Delta [Behaira Governorate], where S. mansoni infection is prevalent, all residents of both sexes between 5 and 50 years of age [n = 858] were examined for S. mansoni. The prevalence of S. mansoni was 69%. Infected subjects were treated with the same dose of Praziquantel during January-February 1994, with an overall resultant efficacy of 85.5% [471/551] and 97.2% [103/106] in 18-40 years old males 8-10 weeks post-treatment. The high cure rate in the second study was probably because treatment took place at 2 months after the end of the high transmission season

Prevalence of schistosomiasis and dynamics of its distribution in some villages in Qualyoubia governorate

A total of 1535 persons of different age, sex and occupation from 5 villages [Tanan, El-Sad, Sandiun, Kakrna and Taha-nob] in Qalyoubia Governorate in Nile Delta were subjected to clinical, stool, urine and intradermal tests accompanied by a questionnaire for 500 of them. Snail vectors of schistosoma parasites were collected from 2 villages [El-Sad and Taha-nob] and snail densities in the waterways as well as the prevalence rate of infection with schistosomal cercariae were recorded. The results revealed that the average prevalence rate of Schistosoma hematobium in the 5 villages was 4.9% [range 2.3%- 7.1%] and that of S. mansoni was 13.3% [range 11.4-14.4%]. The overall prevalence of both types was 18.2% [range 13.7-21.4%]. The average density of Biomphalaria alexandrina in the 2 villages was 16.47% and that of Bulinus truncatus was 7.5%, the ratio was 2: 1. The infectivity with schistosomal cercariae was very low with an average of 2.5% in B. alexandrina and 1.5% in B. truncatus. Factors responsible for the decreased rates of schistosomiasis and snail infectivity were discussed

Effect of anti-bilharzial treatment [praziquantel] on urothelium improvement A histopathological and immunological study

The effect of therapy by praziquantel on bilharzial urothelium was studied on 60 patients, 30 cases and 30 control. Cystoscopic and bladder biopsy was taken before and after treatment with praziquantel 40 mg/kg/ body weight for 4 doses one week apart. Cystoscopy after treatment revealed disappearance of the acute lesions: acute ulcers, edema and congestion. But no improvement of chronic lesions; and no changes were found among control group. Histopathological examination shows complete improvement of the acute lesions, granulomatous reaction, degeneration of the living ovae; but no noticeable effect upon the chronic lesions as stromal fibrosis, squamous metaplasia, and no histopathological changes shown among control group. Immunofluorescent deposition positivity was studied in bilharzial Antigen, IgM, IgA and IgG. Bilharzial antigen and IgM immunofluorscent deposition positivily can be used as a marker for detection of the response of treatment with praziquantel especially in acute lesions

Age-targeted chemotherapy for control of urinary schistosomiais in endemic populations

Severity of urinary tract morbidity increases with intensity and duration of Schistosoma haematobium infection. We assessed the ability of yearly drug therapy to control infection intensity and reduce S. haematobium-associated disease in children 5-21 years old in an endemic area of Kenya. In year I, therapy resulted in reduced prevalence (66% to 22%, P < 0.001) and intensity of S. haematobium infection (20 to 2 eggs/10 mL, urine), with corresponding reductions in the prevalence of hematuria (52% to 19%, P < 0.001). There was not, however, a significant first-year effect on prevalence of urinary tract abnormalities detected by ultrasound. Repeat therapy in years 2 and 3 resulted in significant regression of hydronephrosis and bladder abnormalities (41% to 6% prevalence, P< 0.001), and further reductions in proteinuria. Repeat age-targeted therapy was associated with decreased prevalence of infection among young children (< 5yr) entering into the target age group. Two years after discontinuation of therapy, intensity of S. haematobium infection and ultrasound abnormalities remained suppressed, but hematuria prevalence began to increase (to 33% in 1989). Reinstitution of annual therapy in 1989 and 1990 reversed this trends. We conclude that annual oral therapy provides an effective strategy for control of morbidity due to S. haematobium on population basis, both through regression of disease in treated individuals, and prevention of infection in untreated subjects

The impact of Schistosoma haematobium infection and of praziquantel treatment on the growth of primary school children in Bertoua, Cameroon

The association between urinary schistosomiasis and anaemia among infected children remains controversial. The purpose of this study was to determine the impact of schistosoma haematobium infection and treatment with praziquantel on hemoglobin levels among male children aged 6-15 years in Bertoua. Urine examination of 2665 children revealed an infection rate of 23.9 per cent. Children with moderate infection were randomly selected into treatment (238) and placebo (198) groups. Among uninfected children; 174 were randomly selected to serve as controls. Malaria; geohelminth infections and hemoglobin levels were determined before and six months after praziquantel/placebo intervention