Aspectos biológicos da neurocisticercose: alterações do liqüido cefalorraquidiano

Effective immune protection of pigs against cysticercosis

A scolex protein antigen (SPA) was prepared from cysticerci of Taenia solium obtained from naturally infected pigs. Yorkshire pigs were vaccinated with SPA plus incomplete Freund's adjuvant (IFA) or with SPA plus Corynebacterium parvum (CP). Controls were given IFA plus phosphate-buffered saline (PBS) or CP plus PBS. All animals were given three subcutaneous injections at 20-day intervals. Ten days after the third injection, the pigs were fed with 10(4) viable eggs of T. solium. All pigs developed a delayed type hypersensitivity, and a transient eosinophilia after the first dose of vaccine. High titers of specific antibodies were detected in the sera of vaccinated animals and in infected controls. A protection level of 71.43% was recorded in animals vaccinated with SPA plus IFA and of 75.00% in those vaccinated with SPA plus CP.

[Neurologic and laboratory findings in a population of an endemic area for taeniasis-cysticercosis, Lagamar, MG, Brazil (1992-1993)]

A clinic-epidemiological enquiry was conducted on in an endemic area for teniasis-cysticercosis. From the whole population 1080 (32.2%) individuals were examined. We found 198 (18.3%) individuals referring teniasis-bearing in the past, and 103 (9.5%) affirming to have had convulsions, either in the past or present. From the last group, 39 (37.8%) indicated that the crisis had begun in adulthood. From the group of patients presenting convulsions, 62 (62%) had laboratory tests performed. Computed tomography showed intracranial calcifications in 21 (33.8%) patients, variable in number and location, suggesting neurocysticercosis and no evidence of disease activity. Electroencephalograms showed abnormal waves in 21 (33.8%) patients and cerebrospinal fluid analyses were altered in 27 (43.5%) cases, having detected eosinophils only in 3 (4.8%) patients. Spinal fluid tests for cysticercosis through enzyme linked immunosorbent assay (ELISA) or indirect immunofluorescence were taken in only 26 (41.9%) patients, obtaining positive results in 6 (23%) samples. Varying upward shifts of protein levels were found in spinal fluid analysis. Assuming that all epidemiologic risk factors for teniasis-cysticercosis in the studied region and its correlation with the laboratory alterations described in convulsing crisis, a prevalence of 1.9% for neurocysticercosis was found.

Cysticercosis of the central nervous system. II. Spinal cysticercosis

The compromising of the spinal canal by cysticercus is considered infrequent, varying from 16 to 20% in relation to the brain involvement. In the spinal canal the cysticercus predominantly places in the subarachnoid space. Clinical signs in spinal cysticercosis can be caused by direct compression of the spinal cord/roots by cysticerci and by local or at distance inflammatory reactions (arachnoiditis). Another mechanism of lesion is degeneration of the spinal cord due to pachymeningitis or circulatory insufficiency. The most frequent clinical features are signs of spinal cord and/or cauda equina compression. The diagnosis of spinal cysticercosis is based on evidence of cerebral cysticercosis and on neuroradiological examinations (myelography and myelo-CT) that show signs of arachnoiditis and images of cysts in the subarachnoid space and sometimes, signs of intramedullary lesions, but the confirmation can only be made through immunological reactions in the CSF or during surgery. The clinical course of 10 patients with diagnosis of spinal cysticercosis observed among 182 patients submitted to surgical treatment due to this disease are analyzed. The clinical pictures in all cases were signs of spinal cord or roots compression. All but two presented previously signs of brain cysticercosis. Neuroradiological examinations showed signs of arachnoiditis in 4 patients, images of cysts in the subarachnoid space in 5, and signs of arachnoiditis and images of cysts in one. The 6 patients that presented intraspinal cysts were submitted to exeresis of the cysts and 2 patients with total blockage of the spinal canal underwent surgery for diagnosis. The 2 remaining patients with arachnoiditis and blockage of the spinal canal were clinically treated. All of the six patients submitted to cyst exeresis had initial improvement but 4 of them later developed arachnoiditis and recurrence of the clinical signs and only 2 remained well for long-term. The 2 non operated patients had no improvement of their clinical signs. Two patients died later due to complications of cerebral cysticercosis. Based on the experience acquired in the management of these patients we indicate surgical treatment for patients that present free cyst in subarachnoid space. For those who present arachnoiditis, surgery is indicated only when there is doubt in the diagnosis. Intramedullary cysts should also be surgically treated.

[Comparative study of immunoenzyme tests ELISA-G and ELISA-M, indirect immunofluorescence, and complement fixation in the diagnosis of human cysticercosis]

A comparative study of four immunological tests used for anti-Cysticercus antibodies detection--Enzyme-Linked ImmunoSorbent Assay IgG (ELISA-G) and IgM (ELISA-M), indirect immunofluorescence (RIFI) and complement fixation (RFC)--was made in serum and cerebrospinal fluid (CSF). 539 patients with symptoms suggesting cysticercosis, 450 relatives of these patients and 133 normal people (control group) were examined. 1122 serum samples and 120 CSF samples were analysed by ELISA-G and RIFI, 83 sera and 60 CSF also by RFC, and 28 CSF by ELISA-M. 5.2% serum samples were reagent in ELISA-G and RIFI, and 3.5% of them had discordant results. All control group sera were negative. The same tests in CSF were positive in 16.7% and had discordant results in 7.5%. ELISA-G and RIFI in serum and CSF had concordant results in 89.6% (17.7% were positive). ELISA-G, RIFI and RFC had concordant results in 54.2% sera (16.9% positives) and in 81.7% CSF (11.7% positives). When ELISA-G and RIFI were negative, RFC was positive in 41.0% sera and 11.7% CSF. ELISA-G and ELISA-M had concordant results in 78.6% CSF. When these results were discordant ELISA-G was positive in 10.7% and ELISA-M in another 10.7%. It is necessary to use concomitantly several immunological tests for anti-Cysticercus antibodies detection in serum and in CSF, in attempting to reach correct diagnosis.

[Neurocysticercosis. I. Clinical and laboratory course of 151 cases]

Neurocysticercosis is a serious public health problem in our midst, which accounted for 7.3% of the hospital admissions and 2.7% of all cases of the out patient clinic attendance of the Discipline of Neurology of the School of Medicine--Ribeirão Preto, São Paulo University, from 1979 to 1986. A total of 151 patients with a minimum follow-up of 6 months were selected for the present study including clinical and laboratory evolution, a topic which is rarely considered in the literature. The onset of the disease was characterized by: epileptic seizures in 82 patients (54.3%), increased intracranial pressure (ICP) in 40 (26.5%), meningitis in 21 (13.9%), headache in the absence of increased ICP or meningitic signs in 7 (4.6%), and spinal cord syndrome in 1 (0.6%). In the group with the epileptic form, 36.6% of the patients later developed other neurological syndromes, such as cysticercotic meningitis, mental disorders and increased ICP after a 6 to 7 years interval. In the group with the hypertensive form, 55% of the patients developed other manifestations during the period of evolution, especially meningitis and epileptic seizures, after a significantly shorter interval than for the epileptic form. In the meningitic form, 19% of the patients showed a recurrence of the syndrome after a mean interval of 10.7 weeks: an additional 66.6% developed a combination with other syndromes, especially increased ICP and epileptic seizures. The death rate was 7.9%, the main cause being increased ICP (83.3%). When the abnormalities of the complementary tests were investigated in the various forms of clinical presentation in terms of their predictive value it was concluded that, in the epileptic form, the presence of cysts in CT scan and/or abnormalities in CSF indicates a greater risk of developing other neurologic syndromes. No significant differences in the patterns of abnormalities of these investigations were detected in the remaining clinical forms. Most cystic lesions detected by CT scan (90.9%) were associated with CSF abnormalities, especially pleocytosis and positive complement fixation test. Conversely, this proportion was only 26% in patients with calcifications.

Results of surgical treatment of neurocysticercosis in 69 cases

The clinical course of 69 patients with neurocysticercosis who underwent surgery to control increased intracranial pressure (ICP) or cyst removal is analyzed. Increased ICP was caused by hydrocephalus in 63 patients, by cerebral edema in four, and by giant cysts in two. Skull x-ray films showed calcifications in 14% and signs of elevated ICP in 46%. Examination of cerebrospinal fluid (CSF) revealed pleocytosis with eosinophils in 52% of cases and a positive complement fixation test for cysticercosis in 66%. Ventriculography allowed localization of the CSF obstruction and ventricular cysts, and generally differentiated between an obstruction due to cysts and an inflammatory process. Computerized tomography showed cysts in the cerebral parenchyma and ventricular dilatation. Ventricular cysts were best seen when intraventricular metrizamide was used. Intracranial shunting and posterior fossa exploration were less effective in the treatment of hydrocephalus than was ventriculoatrial (VA) or ventriculoperitoneal (VP) shunting, although VA or VP shunting was associated with a high percentage of complications. Quality of survival was good in 87% of the cases in the first 3 postoperative months and in 93% of patients who survived 2 years after surgery. Forty-seven patients (68%) were readmitted one or more times for CSF shunt revision; 14 of them for shunt infection (meningitis). The early operative mortality rate was 1.8% for patients with VA or VP shunt placement and 5.3% for those with posterior fossa exploration. The authors conclude that placement of CSF shunts is indicated in the treatment of hydrocephalus, and cyst removal is indicated only when the cyst exhibits tumor-like behavior. Surgical exploration is also indicated when the diagnosis is uncertain.

[Immunoenzymatic test (ELISA) in the diagnosis of neurocysticercosis: study of various antigenic extracts in the detection of IgG antibodies in serum and cerebrospinal fluid samples]

Five different antigens from Cysticercus cellulosae, a vesicular fluid, a saline and an alkaline total extracts, an escolex and membrane, were studied in the ELISA immunoenzymatic assay to demonstrate IgG antibodies in cerebrospinal fluid (CSF) and serum samples. For the 5 antigens the 20 micrograms/ml concentration was selected for polyvinyl plates sensitization for CSF and serum assays. The IgG fraction of a sheep anti-human IgG antiserum was labeled with horseradish peroxidase and revealed with hydrogen peroxide-5-aminosalicilic acid. For positive results 10 ELISA Units for sera and 5 EU for CSF were taken. A total of 182 serum samples and 115 CSF samples were tested. The ELISA sensitivity for sera were 88.6% for vesicular fluid, escolex and membrane; 85.7% for saline extract and 62.8% for alkaline extract. The ELISA sensitivity for CSF was 100% for vesicular fluid and saline total extract, 91.7% for membrane, 89.6% for excolex and 77.1% for alkaline. The ELISA specificity for sera was 100% to the 5 antigens studied; to the CSF was 100% for the alkaline and escolex and 98.5% for the other antigens. An ELISA geometric mean titer of sera and CSF was respectively the 121.1 and 27.3 for vesicular fluid, 111.6 and 31.1 for saline total extract, 30.3 and 5.3 for alkaline total extract, 63.2 and 14.8 for escolex and 69.1 and 18.8 for membrane antigen. ELISA was then compared to immunofluorescence, hemagglutination and complement fixation tests in CSF and sera. ELISA immunoenzymatic assay with saline total extract is recommended for the easy preparation and for the high quantity of antigens obtained, for the high sensitivity and great specificity for sera and CSF; we suggest that this test may be used as a substitute for immunofluorescence, hemagglutination and complement fixation in sera or CSF for the diagnosis of neurocysticercosis.

[Myelin basic protein in cerebrospinal fluid in neurocysticercosis]

Cerebrospinal fluid (CSF) from 115 patients with several neurological disorders were tested for the presence of myelin basic protein (MBP), fragment P1 43-88. Cases were divided into groups according to neurological diagnosis. The control group (50 patients with chronic headache) presented normal CSF composition and presented no evidence of the presence of MBP. MBP was found in: four cases of the 44 of neurocysticercosis; three of the 8 cases of multiple sclerosis; one case of schistosomiasis with spinal cord involvement. Neuroimmunological data are discussed considering results found in this investigation.

[Clinical aspects of neurocysticercosis: analysis of 500 cases]

This was a retrospective study, made at the Hospital das Clinicas University of São Paulo Medical School--Ribeirão Preto from 1956 to 1979 in 500 patients with neurocysticercosis. To our knowledge, this represented the largest sample analysed so far. Clinical manifestations and complemmentary tests were studied. The neurocysticercosis is a serious endemic disease in our region and represented 2.7% of all clinical evaluations by the Neurology Department and 7.5% of all hospital admissions. The most frequent clinical presentations were the epileptic (64.8%), the intracranial hypertension (35.6%), and the meningitic (29%). Radiological study of the skull showed intracranial calcifications suggestive of cysticercosis in 47.6%. The cerebrospinal fluid was abnormal in 81.3%: pleocytosis in 60.9%, increased protein in 49.1% and increased pressure in 29%. The presence of eosinophils occurred in 41.9%, and the Weinberg test was positive in 62,6% of all the cases. It was discussed the utility of the different drugs and the results of the surgical treatment in neurocysticercosis drawing the conclusion that they show no efficacy when analysed at the end of a long follow-up. Since none of the drugs seems to be really efficient, only the sanitary education will be able to control this endemic disease that grasses among us with so somber perspectives.

[Contribution of immunofluorescent reactions in the cerebrospinal fluid to the study of neurocysticercosis]

The most important immunobiological aspects of neurocysticercosis and the cerebrospinal fluid (CSF) syndrome in this disease are reviewed. A study was made of 1.577 samples of CSF from 1.282 patients who suffered from several diseases of central nervous system. They were divided in 3 groups: 1- 459 patients with normal results of CSF tests; 2- 600 patients with pathological CSF, but with immunological reactions non-reactive; 3- 233 patients divided in 8 sub-groups according the results of the immunological reactions. CSF immunofluorescent reactions for syphilis (FTA-Abs). cysticercosis and toxoplasmosis were analysed. Results obtained showed that immunofluorescent reaction for cysticercosis has the same sensitivity and especificity as the complement fixation test, but, not considering those samples who showed delay in hemolisys of the complement fixation test, the immunofluorescent reaction showed significative, better results, as occurs, with the FTA-Abs in syphilis. The agreement between the results of the immunofluorescent reaction and complement fixation in CSF contributes for a better security to the immunodiagnosis of cysticercosis and is particularly useful in those cases in which the complement fixation test in anti-complementary. The positive of immunofluorescent reaction for cysticercosis in CSF must be incorporated to the CSF syndrome of the disease and contributes to the immunobiological studies of the disease.

Eosinophilic granulocytes in cerebrospinal fluid: analysis of 94 cerebrospinal fluid specimens and review of the literature

Eosinophilic granulocytes in the CSF were observed in 94 of approximately 10,000 qualitative cytologic preparations. Those cases of eosinophilia which occurred in the context of a parasitic disease or a puncture-related hemorrhage were excluded. CSF eosinophilia exceeding 1% was found in 57.5% of the cases and 5% in 23.5%. Increased cell counts were observed in 67.7% of the cases; elevated CSF protein values, in 68% to 73%; blood eosinophils, in 10.4%. There was no reason to suspect a relationship between these findings and the number of eosinophils in the CSF.--Fifty-two percent of the cases involved inflammatory diseases of the nervous system; the 18 cases of abacterial inflammation of unknown etiology were particularly striking. In the remaining cases, eosinophils were found in conjunction with cerebral ischemia and hemorrhage, with tumors, and in a relatively high percentage of children (21%). The frequency of occurrence with drained or undrained hydrocephalus was striking. A review of the pathophysiological function of eosinophils indicated that revived or corpuscular antigens were present in all cases of CSF eosinophilia in which an eosinophilic reaction was induced. Nothing can be said at this time, however, concerning the classification of the antigens.

[Eosinophilic meningoencephalitis and blood eosinophilia of parasitic origin]

É relatado o caso de um menino de 12 meses de idade que apresentava febre, rigidez de nuca e hepatoesplenomgalia e que, em dois exames sucessivos, apresentou eosinofilia sangüínea de 72% e 75% e liquórica de 75% e 78%, respectivamente. A biópsia hepática mostrou um granuloma eosinofílico. Embora a criança apresentasse grande infestação por Ascaris lumbricoides, os autores admitem que o quadro clínico apresentado possa ter sido determinado por larvas de Toxocara canis, apesar do parasita não ter sido encontrado.

Imunobiologia da cisticercose: avaliação dos conceitos atuais

O autor procura avaliar os problemas ligados à imunobiologia da cisticercose e os recursos laboratoriais atualmente existentes para o diagnóstico baseando-se, especialmente, em dados sobre a infestação do sistema nervoso central. A análise é conduzida mediante revisão de conhecimentos relacionado à biologia do cisticerco, ao quadro histopatológico por ele desencadeado e às reações biológicas que se patenteiam em exames paraclínicos. Esses fatores são discutidos em relação a aspectos peculiares da doença e orientam as conclusões, entre as quais é apontada a necessidade de estudos mediante experimentação animal e a oportunidade de estudos sobre imunoproteínas para o esclarecimento de pontos ainda duvidosos da patogenia.

Distúrbios psíquicos na neurocisticercose em crianças

Os autores apresentam as observações clínicas de 6 casos de neurocisticercose em crianças, todas do sexo feminino. De um total de 54 casos de neurocisticercose em crianças, destacaram estes 6 nos quais havia, de comum, o fato das pacientes apresentarem intensa agitação psicomotora, com alucinações visuais terroríficas (zoopsias), sendo que 5 destas crianças haviam perdido totalmente a visão, o que tornava o quadro ainda mais dramático. As características clínicas destes casos são relatadas sendo destacada a evolução relativamente satisfatória, tendo em vista o mau prognóstico da neurocisticercose.

Cisticercose intramedular

Os autores apresentam um excepcional caso de cisticercose de localização intramedular sem reações liquóricas características e típicas, com diagnóstico apenas no trans-operatório e confirmação anátomo-patológica.