The WHO ultrasonography protocol for assessing morbidity due to Schistosoma haematobium. Acceptance and evolution over 14 years. Systematic review

Morbidity associated with schistosomiasis in adult population of Chókwè district, Mozambique

BACKGROUND

Mozambique is one of the countries with the highest prevalence of schistosomiasis, although there is little data on the prevalence of disease and associated morbidity in the adult population. This study aimed to describe and characterize the morbidity associated with schistosomiasis in the adult population of Chókwè district and to explore the use of anamnestic questionnaires and urine dipsticks, as well as point-of-care ultrasound for urinary related findings, to better characterize disease prevalence and morbidity.

METHODOLOGY

Between April and October 2018, we conducted a cross-sectional study embedded within the Chókwè Health Research and Training Centre. Data were collected on sociodemographic variables, signs and symptoms for schistosomiasis and water related activities. Infection status was determined by urine filtration, Kato-Katz thick smear and DNA detection. Point-of care urinary tract ultrasonography was performed to assess structural morbidity associated with Schistosoma haematobium infection. Multivariate logistic regression was used to search for associations between risk factors, signs and symptoms, infection status and ultrasound abnormalities.

PRINCIPAL FINDINGS

Our study included 1033 participants with a median age of 34 years old. The prevalence of Schistosoma haematobium, Schistosoma mansoni and ultrasound detected urinary tract abnormalities were 11.3% (95% CI 9.5%-13.4%), 5.7% (95% CI 4.3%-7.5%) and 37.9% (95% CI 34.8%-41.2%), respectively. Of the 37.9% with urinary tract abnormalities, 14.5% were positive for Schistosoma haematobium. Reported hematuria in the last month (p = 0.004, aOR 4.385) and blood in the urine dipstick (p = 0.004, aOR 3.958) were markers of Schistosoma haematobium infection. Reporting lower abdominal pain (p = 0.017, aOR 1.599) was associated with ultrasound abnormalities.

CONCLUSION

Using microscopy and DNA analysis for both Schistosoma haematobium and Schistosoma mansoni in conjunction with urinary ultrasound abnormalities gives us several insights into correlations between disease prevalence (microscopic and anatomical) and demographic details in a high-risk population.

Usefulness of real-time PCR for urogenital schistosomiasis diagnosis in preschool children in a high-prevalence area in Angola

BACKGROUND

Urogenital schistosomiasis caused by Schistosoma haematobium is highly endemic in the municipality of Cubal in Angola. Currently, diagnosis is based on the observation of S. haematobium eggs in urine samples by microscopy but this method has low sensitivity. Few studies have been performed using molecular techniques in high-prevalence areas for the detection of S. haematobium. The objective of this study is to evaluate the usefulness of real-time PCR as a diagnostic technique for urogenital schistosomiasis among preschool-age children and its correlation with morbidity data.

METHODS

A cross-sectional study was conducted in Cubal, Angola, involving 97 urine samples from preschool-age children analyzed by the dipstick test, microscopic examination of filtered urine, and real-time PCR. The diagnosis of urogenital schistosomiasis was based on microscopy and/or real-time PCR results. Clinical and ultrasonography evaluation was performed to rule out complications of schistosomiasis.

RESULTS

We detected a total of 64.95% of samples positive by real-time PCR and 37.11% by microscopy. The sensitivity of parasitological diagnosis of urogenital schistosomiasis by real-time PCR and microscopy was 95.45% and 54.55%, respectively, and the sensitivity of real-time PCR compared with microscopy was 91.67%. A positive real-time PCR result was significantly related to older age (mean = 3.22 years), detection of eggs by microscopy, and abnormal urine dipstick results (18.56% with proteinuria, 31.96% with leukocyturia, and 31.96% with microhematuria) (p-value<0.05). Ultrasound analysis showed that 23.94% of children had urinary tract abnormalities, and it was significantly related to the real-time PCR diagnosis (p-value<0.05).

CONCLUSIONS

Real-time PCR is a more sensitive technique than microscopy for urinary schistosomiasis diagnosis in preschool-age children in Cubal. This increase in sensitivity would allow earlier diagnosis and treatment, thus reducing the morbidity associated with schistosomiasis in its early stages.

Prevalence and morbidity of urogenital schistosomiasis among pre-school age children in Cubal, Angola

BACKGROUND

Schistosomiasis is one of the most important neglected tropical diseases, with a great impact on public health and more than 200,000 deaths annually. Schistosoma haematobium causes urinary tract (UT) morbidity. Since schistosomiasis morbidity control programs focus on children older than 5 years, pre-school age children (PSAC) morbidity is not well known.

METHODS

We conducted a cross-sectional study in Cubal (Angola) among 245 PSAC with the objective of evaluating the prevalence of S. haematobium infection, the intensity of infection, and associated morbidity. For this purpose, urine filtration test followed by microscopic visualization and ultrasound examinations were performed.

RESULTS

The estimated overall prevalence of urogenital schistosomiasis was 30.2% (CI 95%; 24.5-35.9), with 20.3% (CI 95%; 15.3-25.3) of the samples analysed showing a high intensity of infection. A total of 54.5% (CI 95%; 47.6-61.8) of infected children presented UT lesions, showing a significant association between schistosomiasis infection and UT morbidity (p-value < 0.001). Bladder wall thickening was the most common lesion, being present in 100% of abnormal ultrasounds. We found that anaemia and severe malnutrition were not significantly associated with the development of UT lesions.

CONCLUSIONS

S. haematobium infection in PSAC causes great UT detectable morbidities. Therefore, there is an evident need of including them in mass drug administration (MDA) campaigns and consequently the development of an adapted praziquantel treatment dosage for children under 2 years of age.

Schistosoma haematobium urinary tract complications in African migrants attending primary care facilities in Paris, France: A retrospective cohort study (2004-2018)

OBJECTIVES

Little is known about the burden of urogenital schistosomiasis (UGS) outside endemic areas. This study was aimed at describing urinary complications of UGS detected among African migrants in French primary care facilities.

PATIENTS AND METHODS

A retrospective cohort study included patients with UGS diagnosed from 2004 to 2018 in 5 primary health centers in Paris. Cases were defined by the presence of typical Schistosoma haematobium eggs at urine microscopy. Demographic, clinical, biological and imaging data were collected. Ultrasonography (U-S) findings were classified in accordance with the WHO guidelines.

RESULTS

U-S was prescribed for all patients and performed in 100/118. Sex ratio (F/M) was 2/98, and mean age 24.4 years. Patients were from West Africa (73% from Mali) and consulted 8 months (median) after their arrival. Among the 95 patients with interpretable findings, 32 (33.7%) had abnormalities related to UGS, considered as major in 6 cases (6.3%), and mostly localized at the bladder (31/32) without detection of cancer. No sociodemographic, clinical, or biological factors were found to be associated with U-S abnormalities. All 100 patients were treated by praziquantel (PZQ). Among those with abnormalities, 20/32 received two to four doses at various time intervals. Post-cure imaging control performed in 19/32 showed persistent abnormalities in 6 patients, on average 5 months after the last PZQ uptake.

CONCLUSION

Urinary tract abnormalities associated with UGS were common and predominated at the bladder. U-S should be prescribed to any patient with positive urine microscopy. Schedules for PZQ uptake and U-S monitoring for patients with complications remain to be determined.

A 14-year follow-up of ultrasound-detected urinary tract pathology associated with urogenital schistosomiasis in women living in the Msambweni region of coastal Kenya

BACKGROUND

Complications of urogenital schistosomiasis include acute inflammatory and chronic fibrotic changes within the urogenital tract. Disease burden of this neglected tropical disease is often underestimated, as only active, urine egg-patent Schistosoma infection is formally considered. Previous studies have focussed on short-term effects of praziquantel treatment on urinary tract pathology, demonstrating that acute inflammation is reversible. However, the reversibility of chronic changes is less well studied.

METHODS

Our study compared, at two time points 14 y apart, urine egg-patent infection and urinary tract pathology in a cohort of women living in a highly endemic area having intermittent praziquantel treatment(s). In 2014 we matched 93 women to their findings in a previous study in 2000.

RESULTS

Between 2000 and 2014 the rate of egg-patent infection decreased from 34% (95% confidence interval [CI] 25 to 44) to 9% (95% CI 3 to 14). However, urinary tract pathology increased from 15% (95% CI 8 to 22) to 19% (95% CI 11 to 27), with the greatest increase seen in bladder thickening and shape abnormality.

CONCLUSIONS

Despite praziquantel treatment, fibrosis from chronic schistosomiasis outlasts the presence of active infection, continuing to cause lasting morbidity. We suggest that future efforts to eliminate persistent morbidity attributable to schistosomiasis should include intensified disease management.

Ultrasound aspects and risk factors associated with urogenital schistosomiasis among primary school children in Mali

BACKGROUND

Urogenital schistosomiasis is endemic in Mali and is a major cause of serious morbidity in large parts of the world. This disease is responsible for many socio-economic and public health issues. The aim of this study was to investigate the impact of the disease on morbidity and to describe demographic and socioeconomic factors in relation to the status of children with urogenital schistosomiasis in Mali.

METHODS

We conducted a cross-sectional study in November 2021 of 971 children aged 6 to 14 years selected at random from six schools in three districts in the Kayes Region of Mali. Demographic and socioeconomic data were collected on survey forms. Clinical data were collected following a medical consultation. Hematuria was systematically searched for through the use of strips. The search for Schistosoma haematobium eggs in urine was done via the filtration method. The urinary tract was examined by ultrasound. Associations between each of these variables and disease infection were tested using multivariate logistic regression.

RESULTS

The overall prevalence of urinary schistosomiasis detected was 50.2%. The average intensity of infection was 36 eggs/10 ml of urine. The associated risk factors for urogenital schistosomiasis showed that children who bathed, used the river/pond as a domestic water source, and who habitually urinated in the river/pond were more affected (P < 0.05). Children with farming parents were most affected (P = 0.032). The collection of clinical signs revealed that boys had more pollakiuria (58.6%) and dysuria (46.4%) than girls. Ultrasound data showed that focal lesion rates were recorded in all villages with the lowest rate in Diakalel (56.1%). Ultrasound and parasitological findings showed that irregularity and thickening were strongly associated with urinary schistosomiasis (P < 0.0001).

CONCLUSIONS

Schistosoma haematobium infection was still endemic in the study site despite more than a decade of mass treatment with praziquantel. However, the high percentage of symptoms associated with high intensity reinforces the idea that further studies in terms of schistosomiasis-related morbidity are still needed.

Management of imported complicated urogenital schistosomiasis in Europe: a TropNet retrospective study

BACKGROUND

Schistosomiasis is a neglected tropical disease caused by trematodes of the genus Schistosoma. Schistosoma haematobium causes urogenital schistosomiasis (UGS), a chronic disease characterized by pathology of the urogenital tract leading to potentially severe morbidity for which the treatment is poorly standardized. We conducted a survey in TropNet centres on the clinical presentations and management strategies of complicated urogenital schistosomiasis (cUGS).

METHODS

We reviewed the clinical records of patients seen at TropNet centres over a 20-year timespan (January 2001-December 2020). Case definition for cUGS included the presence of urogenital cancer, obstructive uropathy, kidney insufficiency of all grades and female or male genital involvement leading to infertility. Collected data included demographic information, patient category (traveller or migrant), imaging data, microbiological data (serology results and presence/absence of eggs in urine), histological features and outcome at last visit recorded.

RESULTS

Eight centres contributed with at least one case. Overall, 31 patients matched the inclusion criteria. Sub-Saharan Africa was the most likely place of infection for included patients. Median age was 30.6 years (range 21-46, interquartile ranges, IQR 27-33). Most patients (28/31, 90.3%) were males. Hydronephrosis was the most frequent complication, being present in 18 (58.1%) patients, followed by cancer, present in 5 patients (16.1%); 27 patients (87.1%) required surgical management of some sort. Use of praziquantel varied across centres, with six different regimens employed.

DISCUSSION

Very few cases of cUGSs were found in our survey, possibly indicating underdiagnosis of this condition. Hydronephrosis was the most frequently observed urogenital complication, and most patients required invasive procedures. Infection by S. haematobium can result in considerable morbidity, resulting in clinically challenging presentations requiring a multidisciplinary approach. As such, development of common protocols for early diagnosis and treatment is urgently needed.

Association of IL-9, IL-10, and IL-17 Cytokines With Hepatic Fibrosis in Human Schistosoma mansoni Infection

This is a case series study to evaluate immunological markers associated with schistosomiasis advanced fibrosis, including 69 patients from an endemic area from the State of Sergipe and from the Hepatology Service of the University Hospital in Sergipe, Brazil. Hepatic fibrosis was classified based on Niamey protocol for ultrasonography (US). Immune response to Schistosoma mansoni antigens was evaluated by stimulating peripheral blood mononuclear cells (PBMCs) from these patients with either adult worm (SWAP-10 μg/ml) or egg (SEA-10 μg/ml) antigens or purified protein derivative of turberculin (PPD-10 μg/ml) or phytohemagglutinin (PHA-1 μg/ml) for 72 h. The levels of IFN-γ, TNF-α, IL-5, IL-10, and IL-17 were measured in these supernatants by ELISA and IL-9 by Luminex. Single nucleotide polymorphisms in IL-17, IL10, and CD209 genes were genotyped using TaqMan probe by qPCR. Higher levels of IL-9, IL-10, and IL-17 were found in PBMC supernatants of patients with advanced hepatic fibrosis. Direct correlations were detected between IL-9 and IL-17 levels with US spleen sizes, portal vein diameters, and periportal thickening. The CD209 rs2287886 AG polymorphism patients produce higher IL-17 levels. Together, these data suggest a role of these cytokines in the immunopathogenesis of advanced fibrosis in human schistosomiasis.

Association of IL-9, IL-10, and IL-17 Cytokines With Hepatic Fibrosis in Human Schistosoma mansoni Infection

This is a case series study to evaluate immunological markers associated with schistosomiasis advanced fibrosis, including 69 patients from an endemic area from the State of Sergipe and from the Hepatology Service of the University Hospital in Sergipe, Brazil. Hepatic fibrosis was classified based on Niamey protocol for ultrasonography (US). Immune response to Schistosoma mansoni antigens was evaluated by stimulating peripheral blood mononuclear cells (PBMCs) from these patients with either adult worm (SWAP-10 μg/ml) or egg (SEA-10 μg/ml) antigens or purified protein derivative of turberculin (PPD-10 μg/ml) or phytohemagglutinin (PHA-1 μg/ml) for 72 h. The levels of IFN-γ, TNF-α, IL-5, IL-10, and IL-17 were measured in these supernatants by ELISA and IL-9 by Luminex. Single nucleotide polymorphisms in IL-17, IL10, and CD209 genes were genotyped using TaqMan probe by qPCR. Higher levels of IL-9, IL-10, and IL-17 were found in PBMC supernatants of patients with advanced hepatic fibrosis. Direct correlations were detected between IL-9 and IL-17 levels with US spleen sizes, portal vein diameters, and periportal thickening. The CD209 rs2287886 AG polymorphism patients produce higher IL-17 levels. Together, these data suggest a role of these cytokines in the immunopathogenesis of advanced fibrosis in human schistosomiasis.

Prospective cohort study using ultrasonography of Schistosoma haematobium-infected migrants

BACKGROUND

Chronic infection with Schistosoma haematobium may lead to serious complications, including bladder carcinoma. Although it is recommended that only bladder masses not regressing within 6 months after praziquantel intake should be investigated invasively, cystoendoscopy is still often performed at diagnosis even in the absence of further signs of concern. No prospective study so far evaluated the evolution of bladder lesions after treatment in case of no risk of reinfection, which could inform case management.

METHODS

Adult African migrants with active S. haematobium infection, as assessed by positive urine PCR or microscopy for eggs in urine or bladder biopsy, underwent urinary tract ultrasound at enrolment and at 1, 3, 6, 12 and 24 months after praziquantel treatment. Patients in advanced pregnancy or with known Schistosoma-unrelated chronic pathology of the urinary tract were excluded.

RESULTS

Twenty-one patients, aged 18-29 years, participated in the study; ten (47.6%) had bladder masses on ultrasound. Follow-up ≥6 months was completed by 16 (76.2%) patients; ≥12 months by 14 (66.7%) and 24 months by 11 (52.4%). All patients with bladder lesions on enrolment completed a follow-up of ≥6 months. Lesions resolved completely by 6 months in all cases and no new development/re-appearance was observed.

CONCLUSIONS

This is the first prospective, long-term follow-up study with ultrasound of patients with urinary schistosomiasis outside endemic areas. Mucosal masses in young patients regressed after treatment without recurrence, supporting the recommendation that invasive procedures should be avoided unless lesions or other symptoms/signs of concern persist for > 6 months. Further studies should assess the evolution of bladder lesions after treatment in larger populations, including older age groups, and, ideally, with parallel assessment of other biomarkers of urinary pathology and of residual S. haematobium active infection.

Focused Assessment with Sonography for Urinary Schistosomiasis (FASUS)-pilot evaluation of a simple point-of-care ultrasound protocol and short training program for detecting urinary tract morbidity in highly endemic settings

BACKGROUND

Urogenital schistosomiasis (UGS) causes inflammation and fibrosis of the urinary tract. In resource-limited settings, affordable tools for morbidity assessment in clinical care are needed. Point-of-care ultrasound has not yet been validated for UGS-related pathology.

METHODS

We developed a protocol for Focused Assessment with Sonography for Urinary Schistosomiasis (FASUS), assessing pathology of the bladder wall, ureters and kidneys. Following standardized training, two clinicians performed FASUS on children and adults with hematuria in Lambaréné, Gabon. Recorded ultrasound clips were remotely reviewed by two ultrasound experts as a diagnostic reference.

RESULTS

In 2015 and 2016, scans were performed in 118 patients. The image quality was sufficient in 90% of bladder views and more than 97% of kidney views. UGS-compatible pathology was detected in 51/118 (43%) by the operator and in 46/107 (43%) by the experts among baseline scans of sufficient quality. Inter-rater agreement between operators and experts was very good (κ > 0.8) for hydronephrosis and good (κ > 0.6) for bladder wall thickening.

CONCLUSIONS

FASUS is a promising clinical, point-of-care tool for detecting UGS-related urinary tract morbidity in symptomatic patients. Based on larger validation studies, appropriate diagnostic and therapeutic algorithms for the use of FASUS should be established.

Usefulness of ultrasound in sub-Saharan patients with a serological diagnosis of schistosomiasis

OBJECTIVE

To evaluate the usefulness of ultrasound examination in patients with just a serological diagnosis of schistosomiasis but no other evidence of active infection.

METHODS

346 sub-Saharan patients with possible schistosomiasis that presented at a Tropical Medicine Unit between 2008 and 2019 were retrospectively selected. Possible schistosomiasis was considered in those patients with a positive serology for schistosomasis in the absence of direct microbiological isolates, hematuria and/or eosinophilia. Data from ultrasound examinations before and after treatment with praziquantel were collected and categorized following the World Health Organization-Niamey score to standardize the use of ultrasonography for the assessment of schistosomiasis-related morbidity.

RESULTS

Ultrasound examinations were abnormal in only ten patients (2.89%). Main findings were focal thickening of the bladder wall (n = 6), ureteral dilatation (n = 3) and grade I hydronephrosis (n = 1). No malignant lesions, hepatic lesions nor hepatobiliary related disorders were found. After treatment, the S. haematobium global score (5 vs 3.4, p = 0.06) and the urinary bladder score (2 vs 1, p = 0.059) showed a trend towards improvement after treatment. In three patients the score after treatment dropped to 0, and in another three it remained the same although with signs of improvement. No worsening of the score was observed in any case.

CONCLUSION

For those patients with a diagnosis of schistosomiasis based solely in a positive serology, the ultrasound examination could safely be spared due to the low prevalence of pathological findings and its response to treatment anyway.

Associations between infection intensity categories and morbidity prevalence in school-age children are much stronger for Schistosoma haematobium than for S. mansoni

BACKGROUND

World Health Organization (WHO) guidelines for measuring global progress in schistosomiasis control classify individuals with Schistosoma spp. infections based on the concentration of excreted eggs. We assessed the associations between WHO infection intensity categories and morbidity prevalence for selected S. haematobium and S. mansoni morbidities in school-age children.

METHODOLOGY

A total of 22,488 children aged 6-15 years from monitoring and evaluation cohorts in Burkina Faso, Mali, Niger, Uganda, Tanzania, and Zambia from 2003-2008 were analyzed using Bayesian logistic regression. Models were utilized to evaluate associations between intensity categories and the prevalence of any urinary bladder lesion, any upper urinary tract lesion, microhematuria, and pain while urinating (for S. haematobium) and irregular hepatic ultrasound image pattern (C-F), enlarged portal vein, laboratory-confirmed diarrhea, and self-reported diarrhea (for S. mansoni) across participants with infection and morbidity data.

PRINCIPAL FINDINGS

S. haematobium infection intensity categories possessed consistent morbidity prevalence across surveys for multiple morbidities and participants with light infections had elevated morbidity levels, compared to negative participants. Conversely, S. mansoni infection intensity categories lacked association with prevalence of the morbidity measures assessed.

CONCLUSIONS/SIGNIFICANCE

Current status infection intensity categories for S. haematobium were associated with morbidity levels in school-age children, suggesting urogenital schistosomiasis morbidity can be predicted by an individual's intensity category. Conversely, S. mansoni infection intensity categories were not consistently indicative of childhood morbidity at baseline or during the first two years of a preventive chemotherapy control program.

Ultrasound findings in urogenital schistosomiasis: a pictorial essay

Urogenital schistosomiasis is a parasitic disease caused by S. haematobium which is endemic in tropical and sub-tropical areas but is increasingly diagnosed in temperate non-endemic countries due to migration and international travels. Early identification and treatment of the disease are fundamental to avoid associated severe sequelae such as bladder carcinoma, hydronephrosis leading to kidney failure and reproductive complications. Radiologic imaging, especially through ultrasound examination, has a fundamental role in the assessment of organ damage and follow-up after treatment. Imaging findings of urinary tract schistosomiasis are observed mainly in the ureters and bladder. The kidneys usually appear normal until a late stage of the disease.

Delay in schistosomiasis diagnosis and treatment: a multicenter cohort study in Italy

BACKGROUND

Barriers to access to care, different diagnostic strategies and low awareness remain challenging issues in the fight against schistosomiasis.Our study aims to examine management of schistosomiasis in migrants attending large tertiary hospitals in Italy, in order to call for a comprehensive approach.

METHODS

A retrospective review of schistosomiasis cases was carried out between January 1, 2016, and December 31, 2017, in five large Infectious Disease Centers in Italy. We included all patients diagnosed with schistosomiasis. We differentiated among (i) asymptomatic patients diagnosed by serology either as healthy 'migrant evaluation' or as 'late evaluation' in patients followed because of a different infection and (ii) patients tested because of a suggestive clinical presentation. Patients characteristics and clinical data were recorded.

RESULTS

One hundred forty-nine patients were included, 137 (91.9%) were male, the median age was 26 years and 70% of them came from Sub-Saharan Africa.Thirty-eight asymptomatic patients (25.5%) were diagnosed by serology [15, (10.1%) among 'migrant evaluation' and 23 (15.4%) among 'late evaluation' group], and 111 (74.5%) presented with signs/symptoms.The median diagnostic delay from arrival in Italy was 31 months: 110 for asymptomatic group and 16 months for symptomatic patients. Among the 111 symptomatic patients, 41 individuals were already followed in our clinics, and they never underwent screening before appearance of evident disease. Among patients with positive serology who were tested by microscopy, 32/86 (37.2%) had confirmed diagnosis. Forty-five (37.8%) patients presented radiologic abnormalities. Praziquantel was the treatment of choice (70.1% for 3 days and 29.9% in a single-day dose), and 77 (51.7%) were lost to follow-up.

CONCLUSIONS

In our centers, a high proportion of patients were tested late after arrival, and most of them presented with clinical apparent disease. Well-defined strategies and implementation of recent guidelines are needed to improve early diagnosis and to overcome heterogeneity of practice.

Point-of-Care Ultrasound: A Useful Diagnostic Tool in Africa

In resource limited settings with limited tests and diagnostic tools, most of diagnoses are based on clinical findings, and patients are managed empirically, e.g. with anti-tuberculosis drugs. This article aims at describing the use of point-of-care ultrasound in diagnosing the most important conditions in Africa, in addition to clinical work-up. Different protocols exist for the diagnosis of trauma-related disorders, tuberculosis, schistosomiasis, thromboembolism, causes of dyspnea, and non- traumatic shock. Point-of-care ultrasound might be a beneficial tool in Africa, aiding diagnostics and management of patients with these conditions. However, studies must be done to assess the impact of point-of-care ultrasound on mortality.

Sound Around the World: Ultrasound for Tropical Diseases

Ultrasound for diagnosis and staging of schistosomiasis and echinococcosis have paved the way over the past several decades for the application of ultrasound in tropical diseases. Until recently, the size and cost of ultrasound systems limited the application in low-resource settings. The increase in portable ultrasound systems has given more clinicians access to ultrasound, and clinically based protocols for the care of patients have emerged, such as focused assessment with sonography for HIV/TB and tropical cardiac ultrasound. This article explores the history and current use of ultrasound in these diseases and highlights their application in the care of patients.

Ultrasound Evolution of Pediatric Urinary Schistosomiasis after Treatment with Praziquantel in a Highly Endemic Area

Urinary schistosomiasis causes damage to the urological system. Ultrasound is a method that detects the burden of secondary disease, individually and in epidemiological studies. In this study, the Schistosoma haematobium-associated urinary tract pathology is analyzed before and after treatment in a short period of time. Seventy children who had previously participated in an epidemiological study on schistosomiasis in the city of Cubal, Angola, and had also performed urinary ultrasound between August 2013 and February 2014 were cited 6-8 months later to assess the possible reinfection and repeat new urinary ultrasound, analyzing changes at the level of urinary pathology. The presence of hematuria and proteinuria was also analyzed. Of the 70 children analyzed, 29 (41.4%) were girls, with an average age of 10.4 years (standard deviation 2.3). Fifty-three (75.7%) had an improvement in their bladder and/or kidney scores, whereas 12 (17.1%) had no change and five (7.1%) had progression of the disease. None of the parameters analyzed completely disappeared. After one single course of treatment with praziquantel, all the analyzed parameters showed regression. Improvement was greater in the urinary bladder than in the upper urinary tract, though these lesions also reversed; the reversion of all parameters was greater among children older than 10 years old than the younger ones. Proteinuria was the parameter with a smaller reduction. Ultrasound should be a usual tool for diagnosis and follow-up in urinary schistosomiasis, particularly in children; more accurate recommendations about follow-up in the case of children whose lesions do not reverse should be established.

The diagnosis and treatment of urogenital schistosomiasis in Italy in a retrospective cohort of immigrants from Sub-Saharan Africa

OBJECTIVES

To evaluate ultrasound and praziquantel to, respectively, assess and reduce urogenital schistosomiasis (UGS)-associated morbidity in migrants from Sub-Saharan Africa (SSA).

METHODS

Migrants from SSA with UGS attending three Italian centres for tropical diseases during 2011-2016 were retrospectively enrolled. Data on clinical symptoms, routine laboratory, parasitological tests, and ultrasound reported as per the WHO-Niamey protocol were collected at baseline and at available follow-up visits after treatment with praziquantel 40 mg/kg/day for 3 days.

RESULTS

One hundred and seventy patients with UGS were enrolled and treated with praziquantel. Baseline ultrasonography showed urinary tract abnormalities in 115/169 patients (68%); the mean global Schistosoma haematobium score was 2.29 (SD 2.84, IQR 0-2), the mean urinary bladder intermediate score 1.75 (SD 1.73, IQR 0-2), and the mean upper urinary tract intermediate score 0.54 (SD 2.37, IQR 1-10). Abnormalities were more common among the 111 (65%) who were symptomatic (p < 0.02; OR 2.53; 95% CI 1.19-5.35). Symptoms started in 94/111 (85%) before arriving (median 63 months, IQR 12-119). At follow-up, we observed a significant reduction in the prevalence of UGS-related symptoms, blood, urine, and ultrasound abnormalities.

CONCLUSIONS

Our study results support the use of ultrasound and praziquantel for assessing and reducing UGS-associated morbidity in migrants. Health-seeking behaviour, diagnostic, and treatment delays contribute to the advanced pathology and qualified treatment success. To ensure earlier treatment, based on our findings, clinical experience, and available literature, we propose an algorithm for the diagnosis and clinical management of UGS. Multicentre studies are needed to improve the management of subjects with UGS in non-endemic countries.

Correlation between the values of circulating blood elements with the size of spleen in the presence of schistosomal splenomegaly

PURPOSE

To evaluate a possible relationship between the size of the spleen and values of circulating blood elements in patients with schistosomatic splenomegaly.

METHODS

ixty one patients with hepatosplenic schistosomiasis mansoni underwent a clinical exam and peripheral venous blood was collected for a hemogram. The erythrocyte, hemoglobin, hematocrit, leukocyte, and platelet values were determined. All patients underwent abdominal ultrasound to measure the spleen. The hematological test results were compared to the size of the spleen.

RESULTS

The size of the spleen varied from 14.0 to 28.4 (19.9 ± 3.7) cm according to the ultrasound image. Thrombocytopenia was observed 58 (95%) patients, leukopenia in 55 (90%) patients, and anemia in 32 (52.4%) patients. Leukopenia was proportional to splenomegaly.

CONCLUSION

Schistosomal splenomegaly leads to leukopenia in direct proportion to the size of the spleen.

Safety and efficacy of the rSh28GST urinary schistosomiasis vaccine: A phase 3 randomized, controlled trial in Senegalese children

Background

Urinary schistosomiasis, the result of infection by Schistosoma haematobium (Sh), remains a major global health concern. A schistosome vaccine could represent a breakthrough in schistosomiasis control strategies, which are presently based on treatment with praziquantel (PZQ). We report the safety and efficacy of the vaccine candidate recombinant 28-kDa glutathione S-transferase of Sh (rSh28GST) designated as Bilhvax, in a phase 3 trial conducted in Senegal.

Methods and findings

After clearance of their ongoing schistosomiasis infection with two doses of PZQ, 250 children aged 6–9 years were randomized to receive three subcutaneous injections of either rSh28GST/Alhydrogel (Bilhvax group) or Alhydrogel alone (control group) at week 0 (W0), W4, and W8 and then a booster at W52 (one year after the first injection). PZQ treatment was given at W44, according to previous phase 2 results. The primary endpoint of the analysis was efficacy, evaluated as a delay of recurrence of urinary schistosomiasis, defined by a microhematuria associated with at least one living Sh egg in urine from baseline to W152. During the 152-week follow-up period, there was no difference between study arms in the incidence of serious adverse events. The median follow-up time for subjects without recurrence was 22.9 months for the Bilhvax group and 18.8 months for the control group (log-rank p = 0.27). At W152, 108 children had experienced at least one recurrence in the Bilhvax group versus 112 in the control group. Specific immunoglobulin (Ig)G1, IgG2, and IgG4, but not IgG3 or IgA titers, were increased in the vaccine group.

Conclusions

While Bilhvax was immunogenic and well tolerated by infected children, a sufficient efficacy was not reached. The lack of effect may be the result of several factors, including interference by individual PZQ treatments administered each time a child was found infected, or the chosen vaccine-injection regimen favoring blocking IgG4 rather than protective IgG3 antibodies. These observations contrasting with results obtained in experimental models will help in the design of future trials.

Trial registration

ClinicalTrials.gov NCT 00870649

Vaccines represent an attractive tool in the fight against schistosomiasis. Pre-clinical immunization studies with the schistosome enzyme 28 kDa glutathione S-transferase (28GST) have shown a significant reduction of schistosome egg production and subsequent pathology. The objective of the present phase 3 trial was to assess the efficacy and safety of vaccination with the recombinant 28GST of Schistosoma haematobium (rSh28GST) named Bilhvax, in infected school children. After Praziquantel treatment before inclusion and three administrations of rSh28GST at one month interval as primo-vaccination, subjects received a boost injection one year after the first administration. The efficacy was evaluated as a delay of recurrence of urinary schistosomiasis. While immunological analysis showed that Bilhvax induced a consistent immune response characterized by antibodies able to inhibit 28GST enzymatic activity, the efficacy endpoint was not reached. This lack of significant effect may be due to the negative conjunction of a too challenging recurrence criterion associated with safety measures ensuring repeated PZQ treatment. The control of these main factors will be essential for the subsequent trials and must provide evidence of the Bilhvax efficacy as a safe vaccine against uro-genital schistosomiasis.

Schistosomiasis

Schistosomiasis (bilharzia) is a neglected tropical disease caused by parasitic flatworms (blood flukes) of the genus Schistosoma, with considerable morbidity in parts of the Middle East, South America, Southeast Asia and, particularly, in sub-Saharan Africa. Infective larvae grow in an intermediate host (fresh-water snails) before penetrating the skin of the definitive human host. Mature adult worms reside in the mesenteric (Schistosoma mansoni and Schistosoma japonicum) or pelvic (Schistosoma haematobium) veins, where female worms lay eggs, which are secreted in stool or urine. Eggs trapped in the surrounding tissues and organs, such as the liver and bladder, cause inflammatory immune responses (including granulomas) that result in intestinal, hepato-splenic or urogenital disease. Diagnosis requires the detection of eggs in excreta or worm antigens in the serum, and sensitive, rapid, point-of-care tests for populations living in endemic areas are needed. The anti-schistosomal drug praziquantel is safe and efficacious against adult worms of all the six Schistosoma spp. infecting humans; however, it does not prevent reinfection and the emergence of drug resistance is a concern. Schistosomiasis elimination will require a multifaceted approach, including: treatment; snail control; information, education and communication; improved water, sanitation and hygiene; accurate diagnostics; and surveillance-response systems that are readily tailored to social-ecological settings.

Schistosomiasis in immigrants, refugees and travellers in an Italian referral centre for tropical diseases

BACKGROUND

Schistosomiasis is one of the most important neglected tropical diseases. If unrecognised and untreated, the chronic infection can lead to irreversible complications.

METHODS

Retrospective observational study aimed at describing clinical history, laboratory findings and imaging presentation of imported schistosomiasis diagnosed at the Centre for Tropical Diseases, Sacro Cuore Don Calabria Hospital of Negrar, Verona, Italy from 2010 to 2014. The aim of our study was to assess differences in demographic characteristics, clinical presentation, laboratory data and ultrasound findings between immigrants/visiting friends and relatives (VFR) from endemic countries (endemic group) and expatriates/travellers (non-endemic group).

RESULTS

A total of 272 patients were retrieved: 234 in the endemic and 38 in the non-endemic group. Most of the patients acquired schistosomiasis in Africa (97.4%). Symptoms were reported by 52.9% of the patients; abdominal pain (36%), macroscopic hematuria (11.3%), and genito-urinary symptoms (7.4%) being the most frequently reported. Increased IgE and blood eosinophilia were observed in 169 (63.8%) and 130 (47.8%) patients, respectively. The proportion of positive serology was 250/272 (91.9%).The Circulating Cathodic Antigen CCA for Schistosoma mansoni was positive in 14/61 individuals (23%). At microscopy, infected subjects were 103/272 (37.9%). The species of Schistosoma found were S. haematobium (47.6%), S. mansoni (46.6%) or both (5.8%). Schistosomiasis was classified as confirmed in 103 (37.9%), probable in 165 (60.6%) and suspected in 4 (1.5%) cases using clinical presentation, laboratory data and ultrasound findings. The infection was further classified based on organ involvement: intestinal (17.9%), hepatosplenic (5.1%), urogenital (48.9%), and indeterminate (43.8%). The comparative analysis of endemic and non-endemic patients highlighted differences in sex and age. Endemic patients had more frequent ova identification (41.9% vs. 13.2%, P < 0.001) and increased IgE (70% vs. 26.3%, P < 0.001) when compared with non-endemic. Multivariate analyses showed that younger age, abnormal ultrasound findings and blood eosinophilia were significantly associated with positive microscopy (OR = 0.94, OR = 2.12, OR = 1.98, respectively).

CONCLUSIONS

Symptoms, eosinophilia and abnormal ultrasound findings were present in about half of patients, without differences between groups. Many patients had positive serology but negative microscopy, indicating that schistosomiasis might be misdiagnosed. A combination of diagnostic tools may facilitate the diagnosis.

Ultrasound findings and associated factors to morbidity in Schistosoma haematobium infection in a highly endemic setting

OBJECTIVE

To evaluate the usefulness of the WHO classification of ultrasound pathological changes and to establish risk factors for morbidity in a highly endemic setting.

METHODS

One hundred and fifty-seven ultrasounds were performed on school-aged children previously diagnosed with urinary schistosomiasis in Cubal, Angola. The findings were analysed according to the WHO guidelines. Factors for morbidity were studied.

RESULTS

Mean age of the children was 8.7 (SD 3.2) years. Pathological changes were found in 85.3% (84.7% in the bladder, 34.4% the ureter and 6.3% kidney lesions). The global score according to the WHO classification was 5.74. Male gender [OR 2.61 (1.04-6.58); P 0.043] and older age [OR 2.96 (1.17-7.46); P 0.023] were associated with a higher risk of developing any kind of urinary abnormality. Proteinuria was present in 61.7% of the children. Macroscopic haematuria [OR 2.48 (1.11-5.58); P = 0.02)] and a high level of proteinuria > 300 mg/dl [OR 5.70 (2.17-14.94); P 300 mg/dl)] were associated with abnormalities of the upper urinary tract and showed good positive and negative predictive values for the detection of pathology in the upper urinary tract (65.5% and 71.1%, respectively).

CONCLUSIONS

Severe urinary tract pathology was found in a high percentage of the children in our setting. Microhaematuria and proteinuria were good markers of morbidity, proteinuria being more precise for severe alterations of the upper urinary tract. We suggest initial and evolutive ultrasound in children diagnosed with schistosomiasis, and close monitoring including periodic controls. As schistosomiasis control efforts are currently focused on reducing morbidity, tests that detect the presence or degree of morbidity are essential for targeting treatment and tracking the progress of control campaigns.

Nationwide cross-sectional survey of schistosomiasis and soil-transmitted helminthiasis in Sudan: study protocol

Background

Schistosomiasis and soil-transmitted helminthiasis (STHs) are target neglected tropical diseases (NTDs) of preventive chemotherapy, but the control and elimination of these diseases have been impeded due to resource constraints. Few reports have described study protocol to draw on when conducting a nationwide survey. We present a detailed methodological description of the integrated mapping of schistosomiasis and STHs on the basis of our experiences, hoping that this protocol can be applied to future surveys in similar settings. In addition to determining the ecological zones requiring mass drug administration interventions, we aim to provide precise estimates of the prevalence of these diseases.

Methods

A school–based cross-sectional design will be applied for the nationwide survey across Sudan. The survey is designed to cover all districts in every state. We have divided each district into 3 different ecological zones depending on proximity to bodies of water. We will employ a probability-proportional-to-size sampling method for schools and systematic sampling for student selection to provide adequate data regarding the prevalence for schistosomiasis and STHs in Sudan at the state level. A total of 108,660 students will be selected from 1811 schools across Sudan. After the survey is completed, 391 ecological zones will be mapped out. To carry out the survey, 655 staff members were recruited. The feces and urine samples are microscopically examined by the Kato-Katz method and the sediment smears for helminth eggs respectively. For quality control, a minimum of 10% of the slides will be rechecked by the federal supervisors in each state and also 5% of the smears are validated again within one day by independent supervisors.

Discussion

This nationwide mapping is expected to generate important epidemiological information and indicators about schistosomiasis and STHs that will be useful for monitoring and evaluating the control program. The mapping data will also be used for overviewing the status and policy formulation and updates to the control strategies. This paper, which describes a feasible and practical study protocol, is to be shared with the global health community, especially those who are planning to perform nationwide mapping of NTDs by feces or urine sampling.

Electronic supplementary material

The online version of this article (10.1186/s12889-017-4719-4) contains supplementary material, which is available to authorized users.

Ultrasonographic evaluation of urinary tract morbidity in school-aged and preschool-aged children infected with Schistosoma haematobium and its evolution after praziquantel treatment: A randomized controlled trial

Background

Schistosoma haematobium infections are responsible for significant urinary tract (UT) complications. Schistosomiasis control programs aim to reduce morbidity, yet the extent of morbidity in preschool-aged children and the impact of treatment on morbidity reduction are not well studied.

Methodology

Our study was embedded in a randomized, placebo-controlled, single-blind trial in Côte d’Ivoire, which evaluated the efficacy and safety of three doses (20, 40 and 60 mg/kg) of praziquantel in school-aged (SAC) and preschool-aged (PSAC) children infected with S. haematobium. Enrolled children were invited to participate in an ultrasound examination prior and six months after treatment. At these time points 3 urine samples were collected for parasitological and clinical examinations.

Principal findings

162 PSAC and 141 SAC participated in the ultrasound examination at baseline, of which 128 PSAC and 122 SAC were present at follow-up. At baseline 43% (70/162) of PSAC had UT morbidity, mostly at bladder level and 7% had hydronephrosis. 67% (94/141) of SAC revealed mainly moderate UT pathology, 4% presented pseudopolyps on the bladder wall, and 6% had pyelectasis. At follow up, 45% of PSAC and 58% of SAC were S. haematobium positive, mostly harboring light infection intensities (41% and 51%, respectively). Microhematuria was present in 33% of PSAC and 42% of SAC and leukocyturia in 53% and 40% of PSAC and SAC, respectively. 50% (64/128) of PSAC and 58% (71/122) of SAC presented urinary tract morbidity, which was mainly mild. A significant correlation (p<0.05) was observed between praziquantel treatment and reversal of S. haematobium induced morbidity. Progression of UT pathology decreased with increasing praziquantel dosages. A worsening of morbidity was observed among children in the placebo group.

Conclusion/Significance

Bladder morbidity is widespread among PSAC. Praziquantel treatment is significantly associated with the reversal of S. haematobium induced morbidity, which underscores the importance of preventive chemotherapy programs. These programs should be expanded to PSAC to prevent or decrease the prevalence of morbidity in young children. This trial is registered as an International Standard Randomized Controlled Trial, number ISRCTN15280205.

Schistosoma haematobium is a parasite that infects the human genito-urinary tract. People get infected with the parasite through contact with fresh water and children are at major risk. The complications linked to this infection are due to an inflammation caused by accumulation of the eggs in peri-bladder veins. If not treated, infections can last years and different degrees of severity are observed. These range from thickening of the bladder wall and blurriness of the mucosa to more serious lesions such as pseudo polyps and masses in the bladder that can, with time, evolve in cancer of the bladder. We analyzed preschool-aged children (PSAC) and school-aged children (SAC) with ultrasound before and after praziquantel treatment. Children were randomly assigned to different doses of praziquantel (20, 40 or 60 mg/kg) or to placebo at baseline. Six months after treatment all children underwent another ultrasound of the urinary tract. We included 162 PSAC and 141 SAC at baseline, of which 128 PSAC and 122 SAC had a second ultrasound evaluation six months afterwards. In addition, urine was sampled at both time points for presence of blood, proteins and signs of infection (leukocytes and nitrates). Six months post-treatment 45% of PSAC and 58% of SAC were S. haematobium positive. Already at the first screening 43% of PSAC and 67% of SAC had bladder lesions. After treatment 50% of PSAC and 58% of SAC still had pathology linked to the infection. We found a correlation between the treatment dose and healing of bladder lesions. On the other hand, we experienced an aggravation of lesions in the placebo group. Praziquantel is given to SAC as preventive chemotherapy every year at national level, where this parasite is endemic. This program should be expanded and include PSAC as well in order to reduce the consequences of infection.

Notes from the Field: Splenomegaly of Unknown Etiology in Congolese Refugees Applying for Resettlement to the United States - Uganda, 2015

Approximately 70,000-90,000 refugees are resettled to the United States each year, and during the next 5 years, 50,000 Congolese refugees are expected to arrive in the United States. The International Organization for Migration (IOM) performs refugee medical examinations overseas for the U.S. Refugee Resettlement Program. In 2014, IOM reported that a large number of U.S.-bound Congolese refugees from Uganda had spleens that were enlarged on examination. During two evaluations of refugee populations in western Uganda in March and July 2015, refugees with splenomegaly on physical examination were offered additional assessment and treatment, including abdominal ultrasonography and laboratory testing. Among 987 persons screened, 145 (14.7%) had splenomegaly and received further testing. Among the 145 patients with splenomegaly, 63.4% were aged 5-17 years (median = 14.8 years). There was some evidence of family clustering, with 33 (22.7%) of the 145 cases occurring in families.

Acute anuria after a family vacation to Corsica/France

A 12-year-old male patient suffered hematuria. Histopathology of a biopsy showed granulomata suspicious for schistosomiasis. The patient had never travelled outside Europe during his entire lifetime. He had taken frequent bathes in various rivers during his last family holidays 5 months earlier in Corsica. Microfiltration of urine revealed viable ova of Schistosoma haematobium with alterated size and shape. Ultrasonography showed a large focal echopoor mass attached to the bladder roof. Four days after antihelminthic therapy, the patient suffered inferior abdominal pain and acute anuria. Ultrasound revealed an approximately 5-cm mass in the bladder lumen suspicious for a large blood clot. After taking non-invasive measures such as drinking high amounts of fluid and treating the lower abdomen with a warm water bag and massage, the clot was excreted with urine and symptoms subsided. The further course was uneventful until 11 months later when hematuria recurred. This time, parasitological urine examination confirmed non-viable schistosome ova. Hematuria was likely due to erosion of the bladder mucosa by calcified non-viable ova.

Schistosoma haematobium in Guinea-Bissau: unacknowledged morbidity due to a particularly neglected parasite in a particularly neglected country

Schistosomiasis is the major neglected tropical helminthic disease worldwide. Current knowledge on the epidemiology of schistosomiasis in Guinea-Bissau is scarce and regarding to the absence of Schistosoma haematobium (S.h.). Therefore, a pilot study was undertaken to assess the prevalence and morbidity due to S.h. infection in randomly selected 90 children and adolescents aged 6 to 15 years. Prevalence of S.h. infection was 20.00 % (18/90). Microhematuria was observed in 61.11 % (11/18) of S.h.-egg-excreting vs. 37.50 % (27/72) of non-S.h.-egg-excreting children p ≤ 0.01. Body mass index (BMI) was less than 15 kg/m(2) in 52/90 (57.78 %) of all children and adolescents, but this proportion increased to 66.67 % (12/18) in S.h.-infected children who were more frequently stunted and wasted than in non-infected children. The mean weight-for-age Z score (WAZ) was reduced in S.h. infected as compared to non-infected children (-1.48 ± 1.08 SD vs. -0.80 ± 1.11 SD; p ≤ 0.01). To our knowledge, this is the first epidemiologic report on S. haematobium infection in Guinea-Bissau since 22 years. Even in this relatively small study sample, it appears that S. haematobium, besides the well-known symptoms such as hematuria, leads to significant, albeit commonly unacknowledged morbidity such as stunting and wasting. These observations underscore the notion that this vulnerable but neglected population urgently needs to be targeted for implementation of measures for treatment and control.

Advances in the Diagnosis of Human Schistosomiasis

Schistosomiasis is a major neglected tropical disease that afflicts more than 240 million people, including many children and young adults, in the tropics and subtropics. The disease is characterized by chronic infections with significant residual morbidity and is of considerable public health importance, with substantial socioeconomic impacts on impoverished communities. Morbidity reduction and eventual elimination through integrated intervention measures are the focuses of current schistosomiasis control programs. Precise diagnosis of schistosome infections, in both mammalian and snail intermediate hosts, will play a pivotal role in achieving these goals. Nevertheless, despite extensive efforts over several decades, the search for sensitive and specific diagnostics for schistosomiasis is ongoing. Here we review the area, paying attention to earlier approaches but emphasizing recent developments in the search for new diagnostics for schistosomiasis with practical applications in the research laboratory, the clinic, and the field. Careful and rigorous validation of these assays and their cost-effectiveness will be needed, however, prior to their adoption in support of policy decisions for national public health programs aimed at the control and elimination of schistosomiasis.