Case records of the Massachusetts General Hospital. Weekly clinicopathological exercises. Case 21-1985. A 21-year-old man with fever, diarrhea, and weakness of the legs during a sojourn in Kenya

The contribution made bySchistosomainfection to non-traumatic disorders of the spinal cord in Malawi

In Malawi, although schistosomal myelopathy has been reported in visitors from overseas who have swum in Lake Malawi, the incidence of this disorder in local residents has never been investigated. Consecutive patients with non-traumatic disorders of the spinal cord were therefore recruited in a hospital and a rehabilitation centre in Blantyre. Of the 33 patients investigated, 16 were presumed to be cases of schistosomal myelopathy as they had the markers of past or current schistosomiasis and apparently no other conditions that could explain their clinical features. There was microscopical and/or immunodiagnostic evidence indicating that eight of these presumptive cases had active schistosomiasis. All 16 presumptive cases had symptoms that were similar to those of 177 presumptive or proven cases of neuroschistosomiasis described in the scientific literature. Following antihelminthic treatment, eight of the presumptive cases showed marked improvement. Schistosomal myelopathy seems to occur relatively frequently in Malawi. Early treatment with praziquantel is strongly recommended for all patients with unexplained myelopathy and a history of exposure to schistosome cercariae.

THE SCHISTOSOMULA TEGUMENT ANTIGEN AS A POTENTIAL CANDIDATE FOR THE EARLY SEROLOGICAL DIAGNOSIS OF SCHISTOSOMIASIS MANSONI

If Schistosoma mansoni infection could be detected in its early stages, especially before the egg deposition in the host tissues, the development of severe pathologic lesions could be efficiently prevented. We therefore developed an indirect enzyme-linked immunosorbent assay based on the detection of specific IgG against schistosomula antigens (ELISA-SmTeg). The assay was applied in sera samples from non-infected and infected mice collected seven and 15 days post-infection. The results were compared to the number of adult worms obtained by perfusion of the murine hepatic system 50 days post-infection. The sensitivity and specificity of the ELISA-SmTeg were 100% (p = 0.0032 and 0.0048 respectively for seven and 15 days of infection) with a cutoff value of 0.15 (p = 0.0002). Our findings show a novel low-cost serological assay using antigens which are easy to obtain, which was able to detect all the infected mice as early as seven days post-infection.

Schistosomiasis of the spinal cord presenting as progressive myelopathy

✓ The authors report on a case of schistosomiasis of the spinal cord in an individual returning to Ireland after a 25-year residence in Africa, where the infection affects approximately 200 million people.

Mielorradiculopatia esquistossomótica

A mielorradiculopatia esquistossomótica é a forma ectópica mais grave e incapacitante da infecção pelo Schistosoma mansoni. A sua prevalência em área endêmica tem sido subestimada. O diagnóstico baseia-se na presença de sintomas neurológicos decorrentes de lesões da medula espinhal em nível torácico baixo e/ou lombar alto, na demonstração da infecção esquistossomótica por técnicas microscópicas ou sorológicas e na exclusão de outras causas de mielite transversa. O tratamento precoce, com esquistossomicidas e corticoesteróides, mostra-se eficaz na maioria dos casos e os pacientes não tratados não se recuperam ou morrem. Não há consenso sobre doses e duração do tratamento, mas estudo recente sugere que os corticoesteróides devam ser usados por pelo menos seis meses. Como o diagnóstico é presuntivo e o tratamento essencialmente clínico, há que se manter alerta para a presença da doença, aperfeiçoar a propedêutica e, dessa forma, evitar-se a laminectomia rotineira. Com o advento da ressonância magnética da medula espinhal houve grande avanço no diagnóstico da esquistossomose medular. Como conseqüência, o número de casos de mielopatia esquistossomótica relatados tem aumentado rapidamente.

Esquistossomose medular: análise de 80 casos

O objetivo deste estudo é analisar dados clínicos e laboratoriais de 80 casos de esquistossomose medular (EM) que possam contribuir para melhorar o diagnóstico e tratamento dessa doença. Em 59 pacientes o estudo foi de maneira prospectiva, em 79 pacientes o diagnóstico foi catalogado como altamente provável, presuntivo, baseado em critérios clínico e laboratoriais. Em um paciente houve confirmação anatomo-patológica. Houve predominância do sexo masculino (63,7%), faixa etária entre 21 e 40 anos (63,7%), procedência nordestina (85%), trabalhador em construção civil (31,2%), esforço abdominal prévio (57,5%), início subagudo (61,2%), forma clínica mielorradiculítica e lesão no cone medular e cauda equina (72,5%). O estudo do líquido cefaloraquidiano mostrou pleocitose e taxas elevadas de proteínas em 100% dos casos, da gamaglobulina em 76.5%, positividade de reações imunológicas específicas (imunofluorescência e/ou ELISA) em 100% dos casos (titulo médio de 1/16 e 61u/dl, respectivamente). Costicosteróides e drogas esquistossomicidas foram administrados em todos os pacientes com evolução satisfatória em 80% dos casos.

Schistosomal myelopathy: urologic manifestations and urodynamic findings

OBJECTIVES

To describe the clinical and urodynamic features of patients with voiding dysfunction secondary to schistosomal myelopathy. Schistosomiasis mansoni is an endemic fluke infection in South America, the Caribbean, and Africa. In the United States and Europe, people may be infected mainly through travel to endemic areas and immigration of infected individuals. Clinical involvement of the spinal cord is a well-recognized complication of the disease. The typical manifestations are those of an acute transverse myelitis, with sudden onset of lower extremity neuropathy associated with bladder and bowel dysfunction.

METHODS

We reviewed the records and urodynamic studies of 14 consecutive patients (10 men and 4 women, age range 23 to 49 years) with schistosomal myelopathy confirmed by cerebrospinal fluid serology for S. mansoni, who were referred for evaluation of voiding dysfunction during a 2-year period. At the time of the urologic evaluation, 9 patients had chronic neurologic and urinary symptoms and 5 had recent onset of acute symptoms. The voiding function history, urologic complications, and outcomes after therapy for schistosomiasis were reviewed.

RESULTS

Of the patients with acute disease (5 patients), the urologic symptoms included urinary retention (3 patients) and incontinence (2 patients). Three of them had concurrent lower back pain and lower limb neurologic deficits. Urodynamic studies were performed in 3 patients and revealed bladder areflexia in 2 patients and detrusor hyperreflexia with external sphincter dyssynergia in 1 patient. The patients were started on clean intermittent catheterization and received praziquantel and corticosteroids. Three patients had complete resolution of their symptoms, one recovered normal voiding function but the neurologic deficits persisted, and one had no clinical improvement. All patients with chronic schistosomal myelopathy presented with lower limb neurologic deficits of varying degrees and urinary symptoms, including difficulty emptying the bladder (7 patients), urinary incontinence (6 patients), and urgency and frequency (2 patients). Laboratory and radiographic evaluation of patients with chronic disease revealed urinary tract infection in 5 patients, hydronephrosis in 2 patients, and bladder calculi in 2 patients. Urologic management consisted of antibiotics, clean intermittent catheterization, anticholinergic medication, and stone removal, as appropriate. In 1 patient, conservative treatment failed and that patient required ileocystoplasty.

CONCLUSIONS

Schistosomal myelopathy is a potential cause of severe voiding dysfunction secondary to spinal cord disease. A high index of suspicion is paramount because early medical intervention can abort the progression of neurologic deterioration.

The immunofluorescence antibody test (IFAT) for the diagnosis of schistosomiasis used in a non-endemic area

OBJECTIVE

To evaluate an immunofluorescence antibody test (IFAT) for diagnosis of schistosomiasis in nonimmune travellers and immigrants from endemic areas.

METHODS

65 patients (48 Danes and 17 immigrants) with schistosomiasis were included. The diagnosis of schistosomiasis was based on the presence of schistosome eggs in faeces, urine, sperm, rectal or bladder biopsies and/or the presence of specific antibodies determined by the serological immunofluorescence antibody test (IFAT). Egg excretion was detected using conventional methods and the IFAT performed on whole S. mansoni schistosomula worms, harvested after 8 weeks from mice. Two patterns of immunofluorescence were observed: Fluorescence in the gut of the schistosome called 'Gut Associated Antigen, GAA', and fluorescence of the surface of the schistosomula called 'Membrane Bound Antigen, MBA'.

RESULTS

Eggs were found in 44% of the Danish patients and in 76% of immigrants. The diagnosis was based on a positive IFAT in 48% of the patients. In patients from nonendemic areas, the finding of antibodies against GAA was diagnostic while optimal sensitivity in the immigrants was reached by measuring antibodies against both GAA and MBA.

CONCLUSION

In patients from nonendemic areas GAA is a sensitive marker of acute infection with schistosomiasis. In patients from endemic areas the demonstration of both GAA and MBA is necessary to properly identify long-lasting, nonacute infections. Egg-detection and/or measurement of CAA and CCA remain the methods of choice to monitor treatment as the immunofluorescence assay may remain positive for several years after treatment.

Spinal cord schistosomiasis. A report of 2 cases and review emphasizing clinical aspects

Schistosomal myeloradiculopathy (SMR) is a severe and little known form of presentation of schistosomiasis mansoni and hematobic schistosomiasis. The literature concerning the entity is scarce, and most publications are limited to isolated case reports. Thus, to consolidate and analyze the knowledge currently available about the disease, I reviewed 231 cases, with emphasis on clinical aspects. Although variations occur, in most cases the clinical picture of SMR is highly suggestive in individuals with epidemiologic antecedents of the infection. Thus, a patient with SMR is usually a young male with no other manifestations of schistosomal infection who presents with lumbar pain, often of a radicular nature, soon followed by weakness and sensory loss of rapid progression in the lower limbs associated with autonomic dysfunction, particularly bladder dysfunction. The most suggestive elements of the entity, and therefore of higher diagnostic value, are the low localization of the spinal cord lesion, the acute or subacute onset of the disease, and the association of manifestations due to medullary and radicular involvement. SMR is commonly classified into clinical or anatomoclinical forms. However, I observed no consensus in this classification even in terms of the terminology used. The analysis performed in this review permitted the introduction of a new concept not yet reported in the literature regarding the possibility that the disease consists of a continuous spectrum, with asymptomatic egg laying in the spinal cord at 1 end of the spectrum and devastating forms at the other end, with most cases occupying an intermediate position and with the various types of damage overlapping and associated to different degrees. This concept applies not only to different patients but also to the same patient at different stages of the disease. Chemical and cytomorphologic examination of cerebrospinal fluid (CSF) almost always revealed mildly or moderately increased total protein concentration and predominantly lymphocytic pleocytosis. Eosinophils, the least nonspecific finding, were detected in the CSF of less than half (40.8%) the patients. Myelography and computed tomography-myelography were altered in 63.3% of cases, but this proportion may be an overestimate. The most frequent changes were images of a filling defect due to expansion of the spinal cord and were almost always demonstrated by the 2 imaging modalities. Although still few in number, early reports suggest that magnetic resonance imaging is more sensitive; however, the changes are also nonspecific, such as those revealed by myelography and computed tomography-myelography. Parasite eggs were demonstrated frequently in a biologic specimen (88.3%), but difficulty in detection was not uncommon. Peripheral blood eosinophilia was detected in 64.5% of patients and represented a nonspecific finding. The detection of anti-Schistosoma antibodies in the serum or CSF was also frequent (94.9% and 84.8%, respectively). The presence of anti-Schistosoma antibodies in serum is of limited value for the diagnosis of schistosomiasis in general, especially among individuals living in endemic areas; however, their quantification in the CSF has proved to be promising for diagnosis in the few studies conducted for this purpose. The large number of variables concerning treatment (such as drugs used and duration of disease at the beginning of treatment), together with the relative lack of information about the natural history of the disease, limit the analysis of aspects related to treatment and prognosis. Nevertheless, it was possible to conclude that corticosteroids and antischistosomotic drugs have a favorable effect on disease outcome and should be administered as early as possible. In addition to early treatment, factors linked to the disease itself affect prognosis. The new cases of SMR reported here are typical and illustrate the data discussed in this literature survey.

Fever in the returned traveler

The most important cause of fever in the returned traveler is malaria. All febrile patients in which malaria is epidemiologically possible require urgent evaluation for P. falciparum malaria, which can be rapidly fatal in the nonimmune patient. Early diagnosis and therapy can prevent severe morbidity and mortality. Other less common causes of undifferentiated fever include acute schistosomiasis, the enteric fevers, rickettsial diseases, leptospirosis, and dengue fever. Early empiric therapy for suspected leptospirosis and the rickettsial infections is encouraged to decrease morbidity and mortality. About a quarter of febrile patients do not have an etiologic agent determined for their illness but recover without sequelae. Patients with fever and hemorrhagic manifestations within 3 weeks of their return need to be isolated for the remote possibility of a highly transmissible agent. Although the febrile traveler is always a challenge, the real world differential diagnosis is limited and a systematic approach via the history, physical examination, and selected laboratory tests is usually sufficient to confirm the diagnosis or eliminate potentially serious infections.

Schistosomiasis in Australian travellers to Africa

OBJECTIVE

To determine the proportion of Australian travellers to Africa at risk of Schistosoma infection, and the proportion of those infected.

DESIGN AND PARTICIPANTS

Retrospective postal survey of 360 patients who had attended Fairfield Hospital travel clinic in 1994 and stated an intention to travel to Malawi, Zimbabwe or Botswana.

MAIN OUTCOME MEASURES

Self-reported risk status for Schistosoma infection. For those at risk, results of an indirect haemagglutination assay (IHA). For those with IHA titres > or = 1:32, results of enzyme-linked immunosorbent assay, urine microscopy and eosinophil count.

RESULTS

360 letters were sent; 35 were returned to sender. Of the 325 remaining, 250 (77%) either responded or had an IHA test; 19 of these were still overseas or did not travel. 117/231 (51%) returned travellers considered themselves at risk of infection. Significantly fewer older patients reported exposure (chi 2 = 66.6; P < 0.001). 109/117 (93%) of those at risk had IHA tests and 18 had titres > or = 1:32. Subsequent testing indicated infection in 10/117 travellers (8.5%; 95% CI, 4.2%-15.2%).

CONCLUSION

Our findings indicate that a considerable number of Australian travellers to Africa are at risk of schistosomiasis, and some are infected. As complications can be serious, screening is recommended for individuals with any risk of infection, and treatment should be offered to those infected.

[Epidemiology and clinical aspects of imported schistosomiasis]

PATIENTS AND METHODS

Travel and medical histories as well as clinical features of 62 German and 21 native patients with schistosomiasis who were presented to a German outpatient clinic for infectious and tropical diseases were investigated in order to identify the risk factor leading to infection in travellers and expatriates.

RESULTS

All patients were able to remember the incidents which led to a likely exposure to cercariae of schistosoma spp. Fifty-nine German patients (95%) acquired infection in Africa, 2 (3%) in South America and one each (2% each) in the Euphrat and the Mekong River, respectively. All but 1 native patients acquired infection in Africa. The highest proportion of infection (45% in Germans and 37% in native patients) was imported from West Africa. Patients returning from this area had had either contact with tributaries of the Niger or with waters of the Volta River, notably the Lake Volta and/or its delta. The most sensitive method for detection of schistosomiasis appeared to be a combination of thorough travel history and serological testing (IHA, IFAT and ELISA) of all patients with possible infection.

CONCLUSIONS

In the investigated group, most infections were acquired by travellers on a lengthy and adventurous journey or by expatriates venturing outside their normal areas of activity. Most patients knew that they travelled in an area endemic for schistosomiasis but were uninformed about the risks they took with their behaviour in a specific setting. Others simply could not avoid skin exposure to freshwater like backpacking tourists travelling in boats on the Niger or Congo River and native patients. Travellers to the tropics should therefore be informed thoroughly about the dangers of water-related diseases such as schistosomiasis.

Genital Schistosomiasis After a Missed Diagnosis of Katayama Syndrome

Schistosomiasis is increasingly reported in travelers to subSaharan Africa.1,2 Bathing in tropical lakes3 or in other fresh waters2,4 is a recognized risk factor for acquiring it. Most cases present with cercarial dermatitis or, 3 to 6 weeks after infection by Schistosoma mansoni1,2 (occasionnally Schistosoma haematobium), with acute schistosomiasis (Katayama syndrome), when the immune response of the body to the larval maturation and migration elicits fever, sweating, arthralgia, urticaria, and digestive or respiratory symptoms. Late and unusual clinical presentations in travelers include features of spinal cord compression5,6 and ectopic dermal or genital localization,3,7 which can result from a missed diagnosis of the early symptoms of the disease. In the following case, a female traveler developed genital schistosomiasis 1 year after a missed diagnosis of Katayama syndrome.

Schistosomiasis in Travelers and Expatriates

Background: Several outbreaks of schistosomiasis among travelers, expatriates, and military serviceman have been reported in recent years. Methods: The travel histories and anamnestic and clinical features of 62 patients with schistosomiasis, who presented to a German outpatient clinic specializing in infectious and tropical diseases, were investigated to identify risk factors that could lead to infection in travelers and expatriates. Results: All patients remembered incidents that led to a likely exposure to cercariae of Schistosoma sp. Fifty nine patients (95%) acquired infection in Africa, two (3%) in South America, and one each (2% each) in Iraq and the Mekong River, respectively. The highest proportion of infection (45%) was imported from West Africa. Patients returning from West Africa reported either contact with tributaries of the Niger (including freshwater pools in the Dogon country, Mali) or with waters of the Volta River, notably Lake Volta and/or its delta. Six patients (10%) acquired infection in little-visited areas such as Central Africa and the Congo Basin. East Africa (especially Lake Victoria) and Lake Malawi contributed 14 patients (22%) to our study group; a further nine patients (14%) became infected after contact with waters of the Zambezi River. Conclusions: The most sensitive method for detection of possible infection with schistosomiasis appeared to be a combination of thorough travel history and serologic testing by indirect hemagglutination (IHA), immunofluorescence antibody test (IFAT), and enzyme-linked immunosorbent assay (ELISA). Most infections were acquired by travelers on lengthy and adventurous journeys or by expatriates venturing outside their normal areas of activity. Most patients knew that they had traveled in an area endemic for schistosomiasis, but were uninformed about behavioral risks they had taken in specific settings.

Schistosoma mansoni infection involving the spinal cord. Case report

The authors report a case of transverse myelitis caused by Schistosoma mansoni. Although this is a treatable disease if diagnosed in the early stage, it is very rarely seen in developed countries and can result in complications if diagnosis is delayed.

Parasitic infections of the central nervous system in children. Part III: Space-occupying lesions

In the last part of this three-part review of parasitic infections of the central nervous system in children, we consider parasites which due to their size, distribution, or the nature of the host response, tend to cause focal lesions in the brain and spinal cord and therefore present as space-occupying lesions which occasionally mimic malignant tumors. As in Parts I and II, infections are grouped according to their predominant geographic area. Such infections include cysticercosis, one of the more common and important infections of the central nervous system.

Early antibody responses in human schistosomiasis

Early diagnosis is important when handling patients with acute schistosomiasis. This state is usually more severe in travellers and tourists than in the immune, resident patients. With increased travelling to areas endemic for schistosomiasis, a tool is needed to solve the problem of differential diagnosis due to the non-specific symptoms of the early stages of the disease. Early appearance of antibodies against excretory/secretory antigens of the intestinal tract in the adult worm was seen in six individuals recently infected with Schistosoma mansoni, using an indirect immunofluorescence technique. The antibodies were of IgM, IgG and IgA classes, and of the IgG1, IgG3 and IgA1 subclasses as detected by ELISA using an antigen preparation of adult worm. On immunoblots, using a freeze-dried adult worm antigen, IgG1 and IgG3 antibodies recognized antigens of 32-35 kD. Antibodies against these antigens could thus be a marker of early infection in previously non exposed visitors to endemic areas.

Diagnostic and clinical aspects of schistosomiasis in 182 patients treated at a Swedish ward for tropical diseases during a 10-year period

Patients treated for schistosomiasis during a 10-year period at a hospital for infectious diseases in Stockholm were investigated by a retrospective analysis in order to evaluate the diagnostic procedures. 80% of the 182 individuals originated from an endemic area and 78% were men. The mean age was 28 years for men and 27 for women. 137 had no other detectable parasites. 127 were asymptomatic. Haematuria was found in 6/15 patients with S. haematobium. 143 patients had infection with S. mansoni. Pathological findings during physical examinations were rare. 61% of the patients had eosinophilia. IgE was a sensitive marker among the patients with a chronic infection (84%). Analysis of antibodies directed against the somatic structure of the adult worm by use of immunofluorescence (IFL) technique had a sensitivity of 80% among the patients with a chronic infection. The detection of antibodies against the gut-associated antigens in IFL indicated an early infection. An enzyme-linked immunosorbent assay (ELISA), using a crude soluble egg antigen, had a sensitivity of 95% and specificity of 96% and is of important diagnostic value.

Acute schistosomiasis mansoni in Finnish hunters visiting Africa: need for appropriate diagnostic serology

Three symptomatic and 3 asymptomatic patients with acute schistosomiasis mansoni are described. The index case presented with fever and eosinophilia 4-6 weeks after swimming in the Pipi River of the Central African Republic, suggesting acute schistosomiasis (Katayama fever). A fortunate early diagnosis led to early treatment of these schistosomiasis patients. Diagnosis was obtained based on the finding of one Schistosoma mansoni egg in the index case and positive serology in all cases. A commercially available passive haemagglutination test for serum bilharzia antibodies was negative in all cases prior to, and 2 weeks after treatment. However, antibodies against gut-associated antigens (GAA) of adult S. mansoni worms could be demonstrated using the indirect immunofluorescence technique. These cases illustrate the importance of using appropriate diagnostic assays for the early demonstration of infection by schistosomes in previously unexposed "nonimmune" patients with atypical symptoms and in asymptomatic individuals at risk even after brief exposure to schistosome-containing water in endemic countries. Careful (and repeated) stool examination and appropriate serological tests are the keys to prompt diagnosis of S. mansoni infection.

Effect of praziquantel on the eggs of Schistosoma mansoni, with a note on the implications for managing central nervous system schistosomiasis

The morphology of Schistosoma mansoni eggs in intestinal tissues (oograms), and egg hatching in faeces, were studied after parenteral administration of praziquantel (PZQ) to infected mice. PZQ was given parentally in doses of 60 mg kg-1 for one day, five days or 10 days. Eleven days after initiation of therapy, oograms from all groups receiving PZQ showed more dead eggs than controls; a dose response was also observed. Depression of faecal egg hatching occurred within 24 hours of PZQ administration. Our observations suggest that PZQ kills most S. mansoni eggs in host tissues when administered in higher doses than are routinely recommended for treatment of intestinal schistosomiasis mansoni. In order to reduce the lifespan of metabolically active eggs in sensitive tissues, prolonged courses of PZQ could be used when treating central nervous system schistosomiasis.

Tumoural form of cerebellar Schistosomiasis mansoni. Report of a surgically treated case

A case of the tumoural form of cerebellar Schistosomiasis mansoni is described. The patient was a 35-year-old female, healthy until one year ago, when she started to show cerebellar and vestibular symptoms. Computerized tomography was performed and showed an expanding lesion in the cerebellar vermis and roof of the fourth ventricle, which was surgically removed. On histopathological examination numerous S. mansoni ova involved in chronic granulomatous inflammation were found. Innumerable granulomas in the productive and healing phases of fibrosis as well as rare ones in the necrotic-exudative phase were observed. This case is compared with another three previously reported in the literature. The clinical picture, diagnostic methods, the relation to the other forms of visceral involvement in Schistosomiasis mansoni and how the parasite reaches the brain are commented upon.

Spinal cord schistosomiasis: a case report and review of the literature

Spinal cord involvement by Schistosomiasis is considered to be rare. We report a case of acute transverse myelitis due to Schistosoma mansoni in which treatment with praziquantal and steroids was started three days after the onset of a paraparesis, with complete neurological recovery.

Schistosomiasis in expatriates returning to Britain from the tropics: a controlled study

Clinical features in 173 white expatriates returning to Britain with the sole diagnosis of schistosomiasis were compared with those in non-infected control subjects, matched for age and sex, returning from similar endemic areas. Infection was, with one exception, acquired in Africa. Schistosoma mansoni was found in 135 patients, S haematobium in 29, and mixed infection in 9. 79% of patients with S haematobium had symptoms, compared with 47% of patients with S mansoni. Tiredness, headache, and gastrointestinal disturbance were no more frequent in symptomatic patients than in control subjects. In over 50% of patients with schistosomiasis the diagnosis was established from snips of rectal mucosa, and this raises the question of how best to look for infection in those who have been exposed. Urine examination and schistosomal serology appear to be the best screening methods; patients with haematuria or seropositivity should be investigated further.