Polyclonal and oligoclonal IgA synthesis in the cerebrospinal fluid of neurological patients: an immunoaffinity-mediated capillary blot study.

An intrathecal synthesis of IgA has been reported in various neurological disorders. However, the frequency of its occurrence and the electrophoretic characteristics of the locally produced IgA remained a matter of controversy. We developed a sensitive immunoaffinity-mediated capillary blot technique for the detection of polyclonal and oligoclonal IgA in the CSF of 115 patients with various neurological disorders. Paired CSF and serum samples containing 50 ng IgA after appropriate dilutions were submitted to isoelectric focusing in agarose gels; IgA was then blotted onto a polyvinylidene difluoride sheet coated by an anti-IgA antiserum or by infectious antigens. The immunoblots were revealed by an alkaline phosphatase-conjugated anti-IgA antiserum. Only five samples displayed CSF-restricted oligoclonal IgA bands, including two out of 33 from MS patients. In herpetic encephalitis (n = 5) and varicella-zoster meningitis (n = 2), a strong intrathecal production of virus-specific IgA antibodies was detectable. In such cases, faint oligoclonal IgA antibodies were superimposed on a polyclonal background. A weak local production of anti-Borrelia burgdorferi IgA antibodies was present in two out of four cases of neuroborreliosis.

Detection of Borrelia burgdorferi in biological samples using the polymerase chain reaction assay.

Oligonucleotide primers were used in the polymerase chain reaction assay to amplify specific DNA regions of the Borrelia burgdorferi 49-kb linear plasmid. One set of primers identifies a 442-bp DNA fragment in the OspA gene and a second pair of amplimers, a 176-bp DNA piece located in the OspB gene. The last set of primers, OspBpc3/pc4, outperformed the other pair in discriminating pathogenic North American or European isolates from related bacterial species, detected down to 4 spirochaetes, and was suitable for the identification of B. burgdorferi in biological samples, such as synovial and cerebrospinal fluids.

Evidence for the involvement of different genospecies of Borrelia in the clinical outcome of Lyme disease in Belgium.

In addition ot Borrelia burgdorferi, recognized as the aetiological agent of Lyme disease, at least two separate genospecies have recently been described. A relationship between infection by strains belonging to different genospecies and clinical outcome has been suspected. In this paper, 9 cases of Lyme arthritis were attributed to infection by B. burgdorferi sensu stricto, 18 cases of neuroborreliosis to B. garinii and one case of acrodermatitis chronica atrophicans to a strain of B. afzelii. These conclusions were based on the preferential reactivity of sera with antigens of given strains in Western blots and on residual reactivity after absorption of sera with antigens of representative strains. No conclusion could be reached concerning sera of 10 patients with erythema migrans.

Virulent Toxoplasma gondii strain RH promotes T-cell-independent overproduction of proinflammatory cytokines IL12 and gamma-interferon.

The aim of this study was the analysis of the cytokine response in BALB/c mice infected with the highly virulent RH or the weakly virulent Beverley strains of Toxoplasma gondii. Analysis of cytokine messages showed increased expression of IL12, IFN-gamma and TNF-alpha, but not IL4 mRNAs in spleen cells after infection with the T. gondii strains RH and Beverley. High levels of circulating IL12 and IFN-gamma were detected in the serum of mice infected with strain RH, although TNF-alpha levels remained low. In contrast, the same cytokines were detected at only low levels in the serum of mice infected with the Beverley strain. Administration of antibody against IL12 or IFN-gamma significantly delayed time to death of mice infected with strain RH compared to controls. T-Cell-deficient as well as normal mice were equally infected by strain RH, suggesting that T lymphocytes do not contribute to the response. Depletion of natural killer cells from the splenocyte population abolished the in vitro production of IFN-gamma. Together, our data suggest that the virulent strain RH induces in BALB/c mice a type 1 cytokine pattern with T-cell-independent overproduction of IL12 and IFN-gamma that may be involved in the pathogenesis of this micro-organism.

Human Granulocytic Ehrlichiosis in Belgium: an underestimated cause of disease.

OBJECTIVES: Human Granulocytic Ehrlichiosis (HGE) is a recently discovered zoonosis and, in Europe, not always included in laboratory testing when a patient presents with a history of tick bite. The available serology results indicate that HGE should be included in the screening panel when a tick-borne disease is suspected. METHODS: Serological methods were applied; i.e. indirect immunofluorescence and Western Blot analysis. Sixty-five serum samples from 47 patients were analysed, of six patients sequential samples were available. RESULTS: 33.8% of the submitted samples were found positive in indirect immunofluorescence, Western Blot confirmed 46.1% of these positive samples. CONCLUSIONS: Although the causative agent and the vector for HGE, Ixodes ticks, are present in Belgium, serology for HGE is seldom solicited. Ehrlichiosis is apparently not always considered as a plausible or possible cause for illness, even when the patient presents with a history of tick bite. We present here a, true be it, incomplete picture of the present situation in Belgium, but nevertheless indicating that it is warranted to test patients with a history of tick bite not only for Lyme disease, but also for HGE.

Human fascioliasis: cure by mebendazole? A case report.

We report a case of invasive human Fasciola hepatica infection in which, for the first time, a successful treatment with high doses of mebendazole (4 g/day for 3 weeks) was achieved. This therapy resulted in a prompt and prolonged normalization of eosinophil counts, liver enzymes abnormalities and specific serological tests together with the disappearance of liver necrosis indicating the eradication of liver flukes. The efficacy of mebendazole in the treatment of fascioliasis must be confirmed by further studies.

Canine Lyme disease in Belgium.

Lyme borreliosis is a multisystem disease caused by the tick-borne spirochaete Borrelia burgdorferi. In addition to causing human illness, borreliosis has been recorded in many species of mammals, including domestic animals which come into contact with the infected tick vector. This paper describes the first two cases to the authors' knowledge of Lyme borreliosis in dogs in Belgium. Both animals suffered recurrent lameness and general prostration. In addition, one of the dogs had recurrent paralysis of nerves V, VII, IX and X, leading to dysphagia and total bilateral paralysis of the mandibular muscles. This complication of Lyme borreliosis has been well documented in human pathology, but has not previously been recorded in the veterinary literature.

[Epilepsy disclosing neuroborreliosis]. / Epilepsie révélatrice d'une neuroborréliose.

After two seizures, a 13 year-old boy experienced headache, fatigue and loss of appetite over a period of 3 weeks. There was a bilateral papilledema with normal visual acuity. CT and MRI disclosed two ischemic foci, that were interpreted as evidence of vasculitis. High serum levels of IgG and IgM antibodies specific to Borrelia burgdorferi, were present. The patient had attended an outdoor scout camp in a area, in south-east Belgium, known to be endemic for tick-born borreliosis. The clinical symptoms, the levels of the specific antibodies and the radiologic abnormalities responded dramatically to treatment. We believe that seizures in this case were related to cerebral vasculitis. This case confirms the extreme diversity of the neurological manifestations of Borreliosis.

[Borrelia burgdorferi encephalomyelitis]. / Formes encéphalomyélitiques de l'infection a Borrelia burgdorferi.

We report two patients with chronic encephalomyelitis due to Borrelia burgdorferi in whom the definite diagnosis was delayed because of atypical clinical features. The first patient presented with chronic spastic paraparesis, slight ataxia and nystagmus of several years' duration. A tentative diagnosis of multiple sclerosis was made in spite of important abnormalities of the CSF biological characteristics. The second patient presented with an acute aphasia and a bilateral Babinski's sign. He was thought to suffer from benign herpetic meningoencephalitis. Several months later, as the patient experienced relapses with cerebellar and spinal cord involvement, falsely positive tests for syphilis were found and an antibiotic treatment was given. High protein content, low glucose levels, pleocytosis and oligoclonal bands were observed in all CSF samples, but the definite diagnosis was based on the detection of serum and CSF antibodies against B. burgdorferi.

[Lyme disease: clinical and sero-epidemiological study of Borrelia burgdorferi infections in Belgium]. / La maladie de Lyme: étude clinique et séro-épidémiologique des infections à Borrelia burgdorferi en Belgique.

Lyme disease is a multi-systemic infection caused by the spirochaete Borrelia burgdorferi: this bacterium, discovered in 1982 in the United States, is mainly transmitted by a tick bite, Ixodes ricinus in Europe. In Belgium, a first seroepidemiological study of 3 years has revealed 190 patients and the whole spectrum of clinical pictures was observed, including the early stage of this infection in the skin (erythema chronicum migrans), neurological involvement and arthritis. The Lyme borreliosis is endemic in our country: the incidence ranges from low near the coast to high in the south-eastern part of Belgium.

[Survey of the infestation level of the Ixodes ricinus tick by Borrelia burgdorferi. Complimentary report]. / Suivi du niveau d'infestation de la tique Ixodes ricinus par Borrelia burgdorferi. Note complémentaire.

In a recent report, we gave results of a 4 year consecutively survey (1987 to 1990) of the level of Ixodes ricinus nymphs infested by Borrelia burgdorferi in two forests of the western part of France. This brought us to conclude that there was a relative stability for this level in course of time. Results of this survey kept on in 1991 oblige us to partly modify our conclusion, on account of an important dropping of the tick infection frequency in one of the two forests, this perhaps in connection with a large observed decreasing of the micromammals populations (but not of ticks ones) due probably to an exceptional drought during all the 1990 year.

[Risk of contamination by Borrelia burgdorferi S. lato in a forest environment. Survey during 13 months of abundance of the tick Ixodes ricinus and its level of infestation by the Lyme borreliosis agent in Brittany]. / Risque de contamination par Borrelia burgdorferi S. lato en milieu forestier. Suivi pendant 13 mois de l'abondance de la tique Ixodes ricinus et de son niveau d'infestation par l'agent de la borréliose de Lyme en Bretagne.

The authors, in a forest in Brittany previously studied for several years, caught by flagging, each month from April 1992 to May 1993, nymphs of I. ricinus tick, and looked by indirect immunofluorescence, for B. burgdorferi infestation. An amount of 1,506 ticks was thus studied. Infestation frequency was varying from 0 per cent in January and February to 14.4 per cent in August. Standarding of tick collecting method allowed to establish, for each month, a tick, "availability" index, and, according to the spirochete infestation frequency, to do estimation of the risk level, for human visiting the concerned forest, of being infected by B. burgdorferi. Obtained results show that this risk is the highest in August, and quite non-existent in January and February.

[Survey during 4 years of the infestation level of the tick Ixodes ricinus (acari Ixodidae) by Borrelia burgdorferi, the agent of Lyme borreliosis, in 2 forests in Brittany]. / Suivi pendant 4 ans du niveau d'infestation de la tique Ixodes ricinus (acarien Ixodidae) par Borrelia burgdorferi, agent de la borréliose de Lyme, dans 2 massifs forestiers de Bretagne.

The authors followed, during 4 years consecutively, from 1987 to 1990, by immunofluorescence, the frequency of B. burgdorferi in an amount of 677 nymphs of I. ricinus tick, collected fasting by flagging in 2 forests in Brittany (France). Percentages obtained in each of these forests do not reveal significative differencies statistically and seem to show a relative stability, from one year to the following, during the considered period, of the infestation levels in ticks.

["Insect bite" and Borrelia]. / "Piqûre d'insecte" et borréliose.

A case of insect bite with a peculiar evolution is presented. The simultaneous inoculation of Borrelia burgdorferi and the treatment are discussed.

[Comparative studies of Toxocara infections in Belgium and in other countries]. / Etude comparative des infections à Toxocara en Belgique et dans les autres pays.

An enzyme-linked immunosorbent assay with larval stage antigen was used to measure the concentration of antibodies to Toxocara sp in 2206 human sera. The results led to the determination of the specificity of our method, the experimental cutoff estimation and the Toxocara sp seroprevalence in different human populations. The prevalence of canine toxocariasis in pet dogs and the associated environmental contamination were studied through examination of 107 faecal and 20 sand-pits samples for Toxocara sp eggs. Our immunological studies and environmental research revealed the existence of toxocariasis as a zoonotic disease in Belgium. We compare here our results with those found in the world literature: in spite of some surprising results, the environmental factors are important for toxocaral infection. The urban residence, the restricted number of playgrounds for children and areas for dogs, the socioecological status are preponderant in the spread of infection.

Pattern of Lyme arthritis in Europe: report of 14 cases.

Fourteen cases of Lyme arthritis are reported. The most frequent picture was that of oligoarthritis appearing in that part of the leg where the cutaneous or neurological complications, or both, of Lyme disease had developed before the arthritis. In most cases recovery followed a single 10 day course of intravenous (IV) penicillin therapy. Arthritis was the presenting feature of Lyme disease in three cases.