Neuroschistosomiasis mansoni: literature review and guidelines.

BACKGROUND: Schistosomiasis is a tropical disease caused by worms of the genus Schistosoma. It is endemic in the Caribbean Islands, the middle east, eastern Asia, South America, and Africa. In nonendemic areas, physicians should be aware of this condition in travelers returning from endemic areas and in immigrants. The main disease-causing species are Schistosoma haematobium, Schistosoma mansoni, and Schistosoma japonicum. Neuroschistosomiasis is an ectopic form of the disease that is mainly associated with S. japonicum infection. Involvement of the central nervous system (CNS) in S. mansoni infection is neglected and underestimated. Neuroschistosomiasis mansoni can be classified into cerebral, spinal, and encephalomyelitic forms in the course of an acute or chronic infection. REVIEW SUMMARY: We review the CNS involvement by S. mansoni infection with an emphasis on life cycle, epidemiology, pathophysiology and immunology, clinical manifestations, diagnostic criteria, differential diagnosis, current treatment guidelines, and prognosis. CONCLUSIONS: Although an underreported CNS infection, found mainly in underdeveloped countries, neuroschistosomiasis mansoni still causes significant incapacity and morbidity. Hence, neurologists should become familiar with this infection worldwide and include it in the differential diagnosis of CNS involvement in travelers returning from endemic areas and in immigrants.

Cerebral and spinal schistosomiasis.

Cerebral schistosomiasis and spinal schistosomiasis are severe underrecognized complications of Schistosoma sp. infection, and can occur at any time during the parasitic infection. Neuroschistosomiasis has been increasingly reported not only in endemic areas but also in Western countries owing to immigration and international travel. Immunogenic interaction between schistosome egg deposition and the delayed hypersensitivity reaction of the host are the main neuropathogenic mechanisms involved. Eggs induce a periovular granulomatous reaction in the tissues. In some cases, schistosome adult worms may aberrantly migrate to the central nervous system via the vertebral venous plexus and place the ova at an ectopic site. Headache and seizures are common in cerebral schistosomiasis, and intracranial hypertension and hydrocephalus may occur in tumour-like and cerebellar schistosomiasis. Spinal schistosomiasis may manifest itself as acute myelitis and/or myeloradiculopathy. Recognition of neuroschistosomiasis is important so that early treatment with praziquantel and steroids can be started in an attempt to prevent severe disability.

Neuroschistosomiasis.

Schistosomiasis (bilharzia) is a neglected tropical disease caused by digenetic trematode platyhelminths of the genus Schistosoma. Neuroschistosomiasis is one of the most severe clinical outcomes associated with schistosome infection. Neurological complications early during the course of infection are thought to occur through in situ egg deposition following aberrant migration of adult worms to the brain or spinal cord. The presence of eggs in the CNS induces a cell-mediated Th2-driven periovular granulomatous reaction. The mass effect of thousands of eggs and the large granulomas concentrated within the brain or spinal cord explain the signs and symptoms of increased intracranial pressure, myelopathy, radiculopathy and subsequent clinical sequelae. Myelopathy (acute transverse myelitis and subacute myeloradiculopathy) of the lumbosacral region is the most common neurological manifestation of S. mansoni or S. haematobium infection, whereas acute encephalitis of the cortex, subcortical white matter, basal ganglia or internal capsule is typical of S. japonicum infection. Cerebral complications include encephalopathy with headache, visual impairment, delirium, seizures, motor deficits and ataxia, whereas spinal symptoms include lumbar pain, lower limb radicular pain, muscle weakness, sensory loss and bladder dysfunction. The finding of eggs in the stool or a positive serology, provides supportive but not direct evidence of neuroschistosomiasis. A definitive diagnosis can only be made with histopathological study showing Schistosoma eggs and granulomas. Schistosomicidal drugs (notably praziquantel), steroids and surgery are currently used for the treatment of neuroschistosomiasis. During the 'acute phase' of the disease, neuroschistosomiasis is treated with corticosteroids which are augmented with a course of praziquantel once female worm ovipositioning commences. Surgery should be reserved for special cases such as in those with evidence of medullary compression and in those who deteriorate despite clinical management.

Neuroschistosomiasis: clinical symptoms and pathogenesis.

Neuroschistosomiasis, referring to schistosomal involvement of the CNS, when symptomatic, is a severe disorder in which prognosis depends largely on early diagnosis and treatment. It is an underdiagnosed disorder, but has been increasingly reported in populations in endemic areas and in tourists. CNS involvement can occur at any time during schistosomal infection. Both the brain and the spinal cord can be affected. Schistosoma mansoni and Schistosoma haematobium usually cause myelopathy, whereas Schistosoma japonicum usually causes encephalic disease. There are substantial differences in the pathogenesis, clinical presentation, and outcome of the neurological disorder, depending on the phase and clinical form of schistosomiasis in which it occurs.

Schistosomal myeloradiculopathy in a low-prevalence area: 27 cases (14 autochthonous) in Campinas, São Paulo, Brazil.

Schistosomal myeloradiculopathy (SMR) is a form of schistosomiasis that is not linked with a high worm burden but rather is found in patients who have been sporadically exposed to Schistosoma mansoni. This paper aims to determine the occurrence of SMR in a low-endemic area with urban transmission in Campinas, São Paulo, Brazil. A retrospective study was performed, identifying confirmed cases in the two largest public hospitals on the region. Patients were diagnosed with SMR using standardised criteria, common clinical parameters, evidence of schistosomal infection and exclusion of other causes of myelopathy. A total of 27 patients were identified; 19 (85.2%) were men and four (14.8%) were women, ranging from 13-57 years of age (mean = 31.2; standard deviation = 12.8). Patients were classified as autochthonous (n = 14; 51.9%) or allochthonous (n = 11; 40.7%) and epidemiological data could not be obtained for two patients (7.4%). The clinical parameters of these patients were not different from previous studies. The sensitivity of serum immune reactions, cerebrospinal fluid immune reactions and parasitological stool examinations in identifying infected individuals was 87.5%, 93.8% and 40%, respectively. The epidemiological importance of these findings and their relationship with the control policies of schistosomiasis are discussed.

Clinical-epidemiologic profile of the schistosomal myeloradiculopathy in Pernambuco, Brazil.

This was a retrospective descriptive study on a series of cases of schistosomal myeloradiculopathy (SMR) and the aim was to investigate the incidence of this disease and its clinical and epidemiological characteristics in cases diagnosed at three healthcare units in Pernambuco, Brazil between 1994-2006. The data were collected by reviewing the medical records from both the neurological and paediatric outpatient clinics and wards of the Hospital Clinics, Hospital of the Restoration and Pernambuco Mother and Child Institute. To gather the data, a spinal cord schistosomiasis evaluation protocol was used. The diagnoses were based on positive epidemiological evidence of schistosomiasis, clinical findings and laboratory tests (stool parasitological examination or rectal biopsies, magnetic resonance imaging findings and cerebrospinal fluid investigations). A total of 139 cases aged between 2-83 years were found. The most important determinants of SMR were male sex (66.2%), contact with fresh water (91%), origin in endemic regions (39.5%), lower-limb muscle weakness (100%), sensory level at the lower thoracic medulla (40.3%), myeloradicular form (76%) and presence of eggs in the stool parasitological examination (48%). This sample indicates the need for intervention policies guided by diagnostic standardization, thereby avoiding disease under-notification.

Research development of the pathogenesis pathways for neuroschistosomiasis.

The infection of the central nervous system (CNS) by schistosome may or may not have clinical manifestations. When symptomatic, neuroschistosomiasis (NS) is one of the most severe presentations of schistosome infection. Among the NS symptoms, cerebral invasion is mostly caused by Schistosoma japonicum (S. japonicum), and the spinal cord symptoms are mainly caused by S. mansoni or S. haematobium. There are 2 main pathways by which schistosomes cause NS: egg embolism and worm migration, via either artery or vein system, especially the valveless perivertebral Batson's plexus. The adult worm migrates anomalously through the above pathways to the CNS where they lay eggs. Due to the differences in species of schistosomes and stages of infection, mechanisms vary greatly. The portal hypertension with hepatosplenic schistosomiasis also plays an important role in the pathogenesis. Here the pathways through which NS occurs in the CNS were reviewed.

Epidemiological aspects in neuroschistosomiasis.

UNLABELLED: The urbanization process of schistosomiasis has been described in the literature. The present report shows and discusses some epidemiological aspects of neuroschistosomiasis that emphasizes this trend. METHOD: The study was done between July, 2005 and June, 2006, and consisted of spinal cord schistosomiasis carriers at the moment of diagnosis. These patients were evaluated whatever the origin and period of the year that they developed the symptoms. RESULTS: A total of 13 patients were evaluated. Ten cases (76.92%) came from the Metropolitan Region of Recife, while the other zones (Zona da Mata, Agreste e Sertão) contributed with just three cases (23.07%). October, November and December (post rainy period) concentrated the majority of the cases (61.54%). CONCLUSION: The high spatial and temporal concentration of cases in relation to a recent endemic area for Schistosomiasis suggests that the immunological status may be an important factor for installation of Sschistosomal myelitis.

Epidemiological aspects in neuroschistosomiasis / Aspectos epidemiologicos na neuroesquistossomose

The urbanization process of schistosomiasis has been described in the literature. The present report shows and discusses some epidemiological aspects of neuroschistosomiasis that emphasizes this trend. Method: The study was done between July, 2005 and June, 2006, and consisted of spinal cord schistosomiasis carriers at the moment of diagnosis. These patients were evaluated whatever the origin and period of the year that they developed the symptoms. Results: A total of 13 patients were evaluated. Ten cases (76.92 percent) came from the Metropolitan Region of Recife, while the other zones (Zona da Mata, Agreste e Sertão) contributed with just three cases (23.07 percent). October, November and December (post rainy period) concentrated the majority of the cases (61.54 percent). Conclusion: The high spatial and temporal concentration of cases in relation to a recent endemic area for Schistosomiasis suggests that the immunological status may be an important factor for installation of Sschistosomal myelitis.

O processo de urbanização da esquistossomose vem sendo descrito na literatura. O presente estudo apresenta e discute alguns aspectos epidemiológicos na neuroesquistossomose que confirmam essa tendência. Método: O estudo foi realizado entre julho de 2005 e junho de 2006, sendo composto por portadores de mielite esquistossomótica no momento do diagnóstico. Os pacientes foram avaliados quanto à procedência e ao período do ano que desenvolveram a doença. Resultados: No total foram 13 pacientes avaliados, sendo 10 casos (76,92 por cento) provenientes da Região Metropolitana do Recife, enquanto as demais regiões (Zona da Mata, Agreste e Sertão) contribuíram com apenas um caso cada. Os meses de outubro, novembro e dezembro concentraram a maioria dos pacientes (61,54 por cento). Conclusão: A alta concentração espacial e temporal de casos em relação a uma área endêmica recente para esquistossomose sugere que a participação de fatores imunológicos possa ser importante para o desenvolvimento de sua forma medular.

[Clinical analysis of 78 cases of parasitic encephalopathy].

OBJECTIVE: To investigate the epidemiology, clinical characteristics, therapeutic approaches and outcomes of parasitic encephalopathy. METHODS: A retrospective study was carried out to analyze 78 cases of parasitic encephalopathy in Huashan Hospital between June 2003 and June 2008. RESULTS: There were 52 male and 26 female patients with a mean age of (34.5+/-11.4) years. Among these patients, 32.1% (25/78) had a history of eating raw, neurocysticercosis accounted for 78.2% (61/78), cerebral sparganosis 15.4% (12/78), cerebral paragonimiasis 3.8% (3/78), and cerebral toxoplasmosis 2.6% (2/78). The common clinical features were epilepsy, headache, nausea, vomiting, vision and hearing loss, facial paralysis and mental retardation. Internal medical therapy resulted in an improvement in 69.2% of the patients. 7 out of 9 patients got improved or cured by combined surgical and internal medical treatment. 42 cases were diagnosed as parasitic encephalopathy while 36 cases (46.1%) were once misdiagnosed as other disorders. CONCLUSION: Parasitic encephalopathy is associated with a history of eating raw, with a high rate of misdiagnosis. Internal medicine combined with surgery is an effective way for the therapy.

Perfil clínico e epidemiológico da mielorradiculopatia esquistossomótica em Pernambuco / Clinical-epidemiological profile of schistosomiasis mielorradiculopathy in Pernambuco

A esquistossomose mansônica é uma doença infecciosa, parasitária e endêmica relacionada com as precárias condições social, econômica e sanitária. O envolvimento do sistema nervoso central é uma das mais intensas formas ectópicas de infecção esquistossomal. Apesar das mielopatias não traumáticas serem freqüentes, as suas ocorrências não estão associadas à real prevalência de mielorradiculopatia esquistossomótica (MRE). Assim, o objetivo deste estudo foi verificar a incidência desta doença e suas características clínicas e epidemiológicas em pacientes diagnosticados em três unidades de saúde de Pernambuco, no período de 1994 a 2006. A coleta de dados foi constituída pelo levantamento de informações em prontuários baseado em protocolos de avaliação, previamente elaborados, específicos para mielorradiculopatia esquistossomótica e para mielopatias de outras causas. O diagnóstico presuntivo baseou-se na epidemiologia positiva para esquistossomose, na comprovação laboratorial através do exame parasitológico de fezes e do líquido cefalorraquediano, e nos exames complementares da ressonância magnética e da biópsia retal. A disponibilização dos dados foi realizada por meio de um sistema de consulta com base em SIG (Sistema de Informações Geográficas), que armazenou todos os dados espaciais para manipulação e ligação dos atributos descritivos às feições gráficas, permitindo a visualização, a análise espacial e, principalmente, a atualização desses dados no sistema. Foram encontrados 139 casos de mielorradiculopatia esquistossomótica, que constituíram o grupo de casos, com uma faixa etária compreendida entre 2 e 83 anos. Os resultados mais relevantes encontrados foram: sexo masculino (66,2 por cento), contato com coleção hídrica (91 por cento), nível da lesão torácica (40,3 por cento), forma mielorradicular (76 por cento), positividade do exame parasitológico de fezes (48 por cento). A maioria dos pacientes utilizou-se de tratamento medicamentoso com corticoterapia (39 por cento) e obteve recuperação parcial sem limitação funcional (57 por cento). A casuística aponta para a necessidade de adoção de uma política de intervenção pautada em padronização propedêutica, evitando a subnotificação da doença. Recomenda-se também a realização de novos estudos que visem o aumento do conhecimento da prevalência dos casos de MRE em Pernambuco. O uso do SIG se mostrou extremamente eficaz, proporcionando o entendimento espacial da distribuição da MRE no Estado e direcionando a execução de ações de controle com importante redução de custos.

Neurological complications of Schistosoma infection.

Schistosomiasis is a parasitic disease caused by blood flukes of the genus Schistosoma. Currently more than 200 million people worldwide are affected. Neuroschistosomiasis constitutes a severe presentation of the disease. Neurological symptoms result from the inflammatory response of the host to egg deposition in the brain and spinal cord. Neurological complications of cerebral schistosomiasis include delirium, loss of consciousness, seizures, dysphasia, visual field impairment, focal motor deficits and ataxia. Cerebral and cerebellar tumour-like neuroschistosomiasis can present with increased intracranial pressure, headache, nausea and vomiting, and seizures. Myelopathy (acute transverse myelitis and subacute myeloradiculopathy) is the most common neurological complication of Schistosoma mansoni infection. Schistosomal myelopathy tends to occur early after infection and is more likely to be symptomatic than cerebral schistosomiasis. The conus medullaris and cauda equina are the most common sites of involvement. Severe schistosomal myelopathy can provoke a complete flaccid paraplegia with areflexia, sphincter dysfunction and sensory disturbances. Schistosomicidal drugs, steroids and surgery are the currently available treatments for neuroschistosomiasis. Rehabilitation and multidisciplinary team care are needed in severely disabled patients.

Morbidity of schistosomiasis mansoni in the state of Minas Gerais, Brazil

From 2002 to 2005, a program of active search for patients with hepatosplenic schistosomiasis and schistosomal myeloradiculopathy has been implemented in the state of Minas Gerais by the local Health Department. The state was divided in 28 regional health centers and the local representatives have been trained to identify and direct patients with hepatosplenic schistosomiasis and neuroschistosomiasis to a reference center in Belo Horizonte, the capital of the state of Minas Gerais. Seventy five patients with hepatosplenic schistosomiasis and 54 with schistosomal myeloradiculopathy have been referred and examined in the reference center in a period of time of 3 years. Schistosomal myeloradiculopathy should be emphasized because the number of cases reported is increasing rapidly and when timely diagnosed and treated, they respond promptly to treatment. Left untreated, they die or become invalid for life. In our view, the time has come for more active investigation of the different aspects of morbidity caused by schistosomiasis mansoni in Brazil.

Morbidity of Schistosomiasis mansoni in the state of Minas Gerais, Brazil.

From 2002 to 2005, a program of active search for patients with hepatosplenic schistosomiasis and schistosomal myeloradiculopathy has been implemented in the state of Minas Gerais by the local Health Department. The state was divided in 28 regional health centers and the local representatives have been trained to identify and direct patients with hepatosplenic schistosomiasis and neuroschistosomiasis to a reference center in Belo Horizonte, the capital of the state of Minas Gerais. Seventy five patients with hepatosplenic schistosomiasis and 54 with schistosomal myeloradiculopathy have been referred and examined in the reference center in a period of time of 3 years. Schistosomal myeloradiculopathy should be emphasized because the number of cases reported is increasing rapidly and when timely diagnosed and treated, they respond promptly to treatment. Left untreated, they die or become invalid for life. In our view, the time has come for more active investigation of the different aspects of morbidity caused by schistosomiasis mansoni in Brazil.

[Clinical profile and criteria for the diagnosis of schistosomal myeloradiculopathy]. / Perfil clínico e critérios diagnósticos da mielorradiculopatia esquistossomótica.

During 20 year period (1972-1992) 56 patients with a diagnosis of schistosomal myeloradiculopathy were admitted in three hospitals of Belo Horizonte-Minas Gerais. Data from patients were collected retrospectively from their medical records. In all cases, the diagnosis was inferred in a presumably way and was based on the following considerations: 1) the finding of low thoracic/upper lumbar neurological symptoms; 2) positive epidemiology for schistosomiasis; 3) demonstration of exposure to schistosomiasis through parasitologic or serologic techniques; and 4) the exclusion of other known causes of transverse myelitis and myeloradiculitis. Several clinical and epidemiological aspects were studied to determine the diagnosis profiles of the schistosomal myeloradiculopathy in this sample and are presented in this paper. In recognizing the many problems in diagnosis of schistosomal myeloradiculopathy we emphasize how important is thinking about this entity and criteria to improve diagnostic evaluation are suggested.

Perfil clínico e critérios diagnósticos da mielorradiculopatia esquistossomótica / Clinical profile and criteria for the diagnosis of schistosomotic myeloradiculopathy

Durante período de 20 anos (1972-1992), 56 pacientes com diagnóstico de mielorradiculopatia esquistossomótica foram internados em três hospitais de Belo Horizonte -- Minas Gerais. Dados de cada paciente foram coletados retrospectivamente de seus prontuários. Em todos os casos, o diagnóstico foi presumido e baseou-se nos seguintes critérios: 1) quadro de comprometimento medular torácico baixo ou lombossacro (síndrome de cone medular e/ou cauda equina); 2) epidemiologia positiva para esquistossomose; 3) comprovaçäo laboratorial de esquistossomose através de exame parasitológico de fezes ou biópsia retal; e 4) exclusäo de outras patologias que pudessem causar quadro semelhante. Vários aspectos clínicos e epidemiológicos foram estudados para determinar o perfil diagnóstico da mielorradiculopatia esquistossomótica nesta amostra e säo apresentados neste artigo. Reconhecendo os vários problemas no diagnóstico da mielorradiculopatia esquistossomótica, enfatizamos a importância de se pensar nesta entidade e sugerimos critérios para definiçäo diagnóstica

[Bilharzian meningomyeloradiculopathy in children]. / La méningo-myélo-radiculite bilharzienne chez l'enfant.

Child meningomyeloradiculitis is a rare complication form of schistosomiasis, even in hyperendemic area. Its diagnosis is very difficult, especially if there are not history or signs of Schistosoma mansoni or hematobium infections. It must be evocated in case of acute flask paralysis occurring in children living in Schistosoma infections endemic area. The authors report a 14-year-old boy's case and suggest etiopathogeny of the disease.