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L A Magnarelli

Publications and source records attributed to L A Magnarelli.

At least 73 records · Page 4Linked to original sources
PubMed1990

Tick parasitism and antibodies to Borrelia burgdorferi in cats.

Ticks were removed from naturally infested cats, and serum samples from these cats were tested for antibodies to Borrelia burgdorferi. Twenty-two of 93 cats (23.7%) had one or more motile stages of Ixodes dammini attached. Of 2 larvae and 20 nymphs removed from cats, 1 larva and 2 nymphs were infected with B burgdorferi. Spirochetes were not found in tissues of 13 female and 4 male ticks. Ten of 71 serum samples analyzed by indirect fluorescent antibody staining or ELISA contained antibodies to this spirochete. Maximal antibody titers were 1:256 and 1:2,560, respectively. At titers greater than or equal to 1:160 in ELISA, seropositivity ranged from 8.8% (n = 34 sera tested from 34 cats) in May through July to 33.3% (n = 12 cats tested) during February through April. In clinical studies of 30 cats, there were nearly equal percentages of seropositive cats with limb or joint disorders not accompanied by fever, anorexia, or fatigue (5 of 21 cats) and cats with these signs of illness but lacking lameness (2 of 9 cats.)

Animals↗
PubMed1990

Serologic testing for Lyme disease.

Serologic testing for antibodies is, at present, the only practical means of diagnosing Borrelia burgdorferi infection. However, specific IgM spirochetal antibodies may not be at detectable concentrations in the early stage of Lyme disease (within 6 weeks of onset). Western blot analysis may be used to confirm indirect fluorescent antibody staining or enzyme-linked immunosorbent assay results, but it is laborious and expensive. False-positive reactions caused by cross-reactivity do occur. In patients who have had subclinical Lyme disease and contract another illness that causes similar symptoms, interpretation of serologic test results may be confused by residual antibodies. Therefore, assay results should always be interpreted in conjunction with clinical and epidemiologic findings.

Antibodies, Bacterial↗
PubMed1990

Persistence of antibodies to Borrelia burgdorferi in dogs of New York and Connecticut.

Multiple blood samples were obtained from privately owned dogs living in tick-infested areas of New York (Westchester County) and Connecticut, where Lyme disease in human beings has been reported. Of the 175 dogs examined, 127 (72.6%) had limb/joint disorder, whereas the remaining 48 dogs were considered healthy. Results of analysis of 419 serum samples revealed IgM antibody to Borrelia burgdorferi in healthy and lame dogs during all seasons. Prevalence of seropositivity was significantly (P less than 0.01) greater, using a polyvalent ELISA (89.5%) than using a class-specific ELISA for IGM antibody (57.8%). Mean antibody titers obtained by use of polyvalent ELISA were likewise higher than IgM titers. Analysis of paired serum samples from dogs with limb/joint disorder indicated that 118 (92.9%) remained positive for IgM or IgG antibodies when retested weeks or months after initial testing. In 48 dogs without history of joint involvement or other signs of disease, 43 (89.6%) had antibody to B burgdorferi 2 or more times. Serotest results also revealed little or no change in antibody titer for lame dogs given antibiotics or for healthy dogs 2 or more months after initial sample collection.

Animals↗
PubMed1990

Isolation of Borrelia burgdorferi from the blood of seven patients with Lyme disease.

PURPOSE: Borrelia burgdorferi, the etiologic agent of Lyme disease, has rarely been successfully cultured from blood. We report on seven patients from Westchester County, New York, with B. burgdorferi bacteremia diagnosed between April 1987 and August 1987. PATIENTS AND METHODS: One hundred thirty-two attempts to isolate spirochetes were made on blood specimens obtained from 104 patients. Twenty-two of these specimens were obtained from nine patients who had recently been bitten by Ixodes ticks but who were asymptomatic. Heparinized blood or serum specimens (0.2 to 0.4 mL) were inoculated onto 6 mL of modified Barbour-Stoenner-Kelly medium. Lyme serology was performed by enzyme-linked immunosorbent polyvalent, IgM, and IgG assays, fluorescent immunoassay, and microhemagglutination. RESULTS: Four of the seven patients had erythema migrans, two had facial nerve palsy, and one had a flu-like syndrome without rash. These patients represented 21% (four of 19) of all patients with the characteristic skin lesion who had blood cultures for B. burgdorferi, and 40% (two of five) of all those with facial nerve palsy. Serologic testing was frequently nonreactive; two patients had no detectable antibody on multiple sera by five different assays. All patients improved with antibiotic treatment, and had negative subsequent blood cultures, but five of seven had persistent complaints after completion of therapy. CONCLUSION: Culturing blood for B. burgdorferi may be useful in confirming the diagnosis of Lyme disease in selected patients. Use of spirochete blood cultures may facilitate a better understanding of the pathogenesis and natural history of Lyme disease.

Adolescent↗
PubMed1990

Infectious but nonpathogenic isolate of Borrelia burgdorferi.

We document for the first time an infectious but nonarthritogenic variant of Borrelia burgdorferi. Strain 25015, previously isolated from an Ixodes dammini larva collected in upstate New York, was infectious but failed to produce arthritis or carditis in laboratory rats and mice. By contrast, pathogenic strain N40 invariably caused arthritis. This nonarthritogenic variant, with proteins with molecular weights different from those of the standard B31 strain, was frequently isolated from normal joint tissues of experimentally infected rats. Outer surface proteins A and B of strain 25015 have molecular weights of about 32,500 and 35,500, respectively, in contrast to molecular weights of approximately 31,000 and 34,000, respectively, for outer surface proteins A and B of strains B31 and N40. A prominent low-molecular-weight protein of about 23,500 also characterizes strain 25015. Test animals infected for 30 to 60 days had relatively high antibody titers (greater than or equal to 1:1,280). The nonarthritogenic variant will be useful, along with pathogenic strains, in providing comparative insight into the pathogenesis of Lyme borreliosis. Homologous immunoblotting of sera from rats and mice inoculated with both the arthritogenic and nonarthritogenic strains revealed antibody reactivities to proteins of B. burgdorferi different from those revealed in the heterologous tests.

Animals↗
PubMed1990

Canine ehrlichiosis in Connecticut.

The first case of canine ehrlichiosis in Connecticut is reported. A female Brittany spaniel from Milford presented with lethargy, anorexia, fever, petechiae, splenomegaly, thrombocytopenia, anemia, elevated serum alkaline phosphatase, lymphopenia, and hypoalbuminemia. Serologic analysis revealed antibodies to Ehrlichia canis (titer, 1:2,560). This documents a more northern geographic distribution in the United States for this infectious agent than had previously been suspected.

Animals↗
PubMed1990

Serologic analyses of cottontail rabbits for antibodies to Borrelia burgdorferi.

An enzyme-linked immunosorbent assay was developed to detect antibodies to Borrelia burgdorferi in cottontail rabbits captured in Millbrook, N.Y., and New York, N.Y. Five antigenically variable strains of B. burgdorferi were analyzed to determine the variability of serologic test results. In analyses of 79 serum samples, seropositivity ranged from 56% for a strain cultured from kidney tissues of a cottontail rabbit to 68% for a strain isolated from a larva of Ixodes dentatus, a tick that parasitized a cottontail rabbit. There were false-positive results when reference rabbit antisera to B. hermsii and Treponema pallidum were screened against B. burgdorferi. Cross-reactivity with antisera to Leptospira interrogans serovars was less pronounced. Western blot (immunoblot) analyses revealed reactivities of test sera to two or more surface or subsurface proteins of B. burgdorferi with approximate molecular masses of 18, 25 to 27, 34, 36, 41, and 59 kilodaltons. Cottontail rabbits respond immunologically to B. burgdorferi, but the observed variations in serologic test results should not be a limitation in field and laboratory investigations of Lyme borreliosis.

Animals↗
PubMed1990

Cross-reactivity of nonspecific treponemal antibody in serologic tests for Lyme disease.

Serum samples obtained from 59 persons who had acute necrotizing ulcerative gingivitis, periodontitis, syphilis, or Lyme disease were tested against Treponema phagedenis biotype Reiter, Treponema denticola, Treponema vincentii, and Treponema scoliodontum by indirect fluorescent-antibody staining methods. Although there were positive reactions for sera representing each of these study groups and for 20 (13%) of 156 samples collected from the general population (premarital screening for syphilis), titration endpoints were relatively low (less than or equal to 1:256). Serum samples from 18 persons who had gingivitis or periodontitis but no history of Lyme borreliosis were tested by enzyme-linked immunosorbent assay for antibodies to Borrelia burgdorferi. Of these, five (28%) had immunoglobulin M antibody and four (22%) contained immunoglobulin G antibodies to this spirochete. Adsorption with either sorbent commercially prepared from T. phagedenis biotype Reiter or with washed, whole cells of T. phagedenis biotype Reiter reduced cross-reactivity in the enzyme-linked immunosorbent assay for Lyme borreliosis.

Antibodies, Bacterial↗
PubMed1990

Bird-feeding ticks transstadially transmit Borrelia burgdorferi that infect Syrian hamsters.

Bird-feeding Ixodes dammini ticks were documented for the first time to successfully molt and transstadially pass Borrelia burgdorferi spirochetes that were indistinguishable by sodium dodecyl sulfate-polyacrylamide gel electrophoresis from the type B31 strain. Forty-six of 73 blood-engorged larvae and 50 of 66 fully-fed nymphs, removed from wild-caught birds, successfully molted. Borreliae were isolated from 21 of 78 partially- and fully-fed larvae off birds, including six specimens that molted. Spirochete-positive cultures also were obtained from 35 of 60 partially- and fully-fed nymphs that had fed from birds, including 20 nymphs that molted into adult ticks. Transstadially passed borreliae by bird-feeding larval and nymphal I. dammini were infectious to hamsters, leading us to suggest that these ticks are capable of subsequently transmitting infectious spirochetes to mammals, including humans. An isolated of B. burgdorferi, recovered from a bird-feeding larval Ixodes dentatus, was indistinguishable by sodium dodecyl sulfate-polyacrylamide gel electrophoresis from the B31 strain. This isolate, unlike another from I. dentatus off a cottontail rabbit (Sylvilagus floridanus), had a protein band with a molecular weight of approximately 31,000 that reacted with murine monoclonal antibodies H3TS and H5332 in western blot analysis. Thus, closely related borreliae are present in both I. dentatus and I. dammini.

Animals↗
PubMed1989

Class-specific and polyvalent enzyme-linked immunosorbent assays for detection of antibodies to Borrelia burgdorferi in equids.

Class-specific and polyvalent ELISA were developed to detect IgM antibody or total immunoglobulins to Borrelia burgdorferi in equine sera. Analyses of 122 serum specimens, collected during 1985 from horses and ponies in tick-infested areas of Connecticut, revealed IgM antibody in 41 (34%) samples; titration end points ranged from 1:160 to 1:2,560. In polyvalent ELISA, 73 (16%) of 454 serum specimens contained IgM and/or IgG antibody. Seropositivity was highest (32%) for blood samples collected during May. Both ELISA procedures had comparable sensitivities.

Animals↗
PubMed1989

Human necrotizing splenitis caused by Borrelia burgdorferi.

A 25-year-old Hispanic male presented to the emergency room with complaints of severe left upper quadrant pain. Physicians determined that the patient had an acute inflammatory process with a possible diagnosis of splenic abscess. A splenectomy was performed. Histologic examination of the tissue sections revealed extensive necrosis and inflammation, but no etiologic agent was discernible. Microbiologic cultures of the tissue had negative results. A Dieterle silver stain revealed an overwhelming number of spirochetal bacteria most closely resembling Borrelia spp. The patient's serum was tested for serologic evidence of antibody to Borrelia burgdorferi with the following results; by indirect fluorescent antibody 1:32; by enzyme-linked immunosorbent assay for IgM, 1:320; and Western blotting had positive results for the presence of B. burgdorferi outer-surface protein antibodies. This is the first human case report of an acute necrotizing splenitis resulting from B. burgdorferi.

Adult↗
PubMed1989

Enzyme-linked immunosorbent assays for Lyme disease: reactivity of subunits of Borrelia burgdorferi.

We prepared fractions of Borrelia burgdorferi, the etiologic agent of Lyme disease, from cultured spirochetes and used them as antigen in an enzyme-linked immunosorbent assay (ELISA) for IgG antibody. Polystyrene plates coated with an extract containing major proteins with apparent molecular masses of 34, 39, 59, and 68 kilodaltons had comparable sensitivity but greater specificity than plates coated with whole cells. Of the 33 serum specimens from individuals with Lyme disease that reacted with whole cells of B. burgdorferi in the class-specific ELISA, 30 (91%) remained positive when this extract was used. Cross-reactivity was minimal with antibody to treponemes. Use of subunit antigens may improve serological diagnosis of Lyme disease.

Antibodies, Bacterial↗
PubMed1989

An outbreak of ehrlichiosis in members of an Army Reserve unit exposed to ticks.

An outbreak of unexplained illness occurred in members of an army reserve unit after field training in an area of New Jersey endemic for Lyme disease. Nine (12%) of the 74 who attended the exercise had serological evidence of Ehrlichia infection, defined as a single rise in titer of antibody to Ehrlichia canis greater than or equal to 1:160 four weeks after training. Two reservists with early serum samples had documented seroconversion, defined by a four-fold or greater increase in titer of antibody to E. canis, with a peak titer of greater than or equal to 1:160. Reservists with serological evidence of Ehrlichia infection were more than three times as likely to report arthralgia, myalgia, headache, appetite loss, nausea, eye pain, and abdominal pain than the other reservists. No reservist with serological evidence of Ehrlichia infection was hospitalized and most had minimal or no symptoms. This outbreak of ehrlichiosis suggests that the usual symptoms of Ehrlichia infection are milder than previously reported and that ehrlichiosis must be considered in symptomatic persons with recent tick exposure.

Animals↗
PubMed1989

Antigenically variable Borrelia burgdorferi isolated from cottontail rabbits and Ixodes dentatus in rural and urban areas.

Spirochetes were isolated from 71 subadult Ixodes dentatus removed from cottontail rabbits captured in Millbrook, N.Y., and in New York, N.Y. Spirochetes were also cultured from kidney tissues of six rabbits. While all isolates reacted with monoclonal antibody H9724, which identifies the spirochetes as borreliae, more than half did not bind with antibody H5332 and even fewer reacted with H3TS, both of which were produced to outer surface protein A of Borrelia burgdorferi. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis protein profiles of three isolates differed from one another and from all previously characterized B. burgdorferi strains from humans, ticks, and wildlife in North America. The 12 periplasmic flagella that originated subterminally from each pointed end of a rabbit Borellia isolate contrasted with the 11 or fewer flagella for B. burgdorferi reported previously from North America. Although DNA homology and restriction endonuclease analysis also revealed differences among a rabbit kidney isolate, an I. dentatus isolate, and B. burgdorferi B31, similarities were sufficient to lead us to conclude that the borreliae in rabbits and I. dentatus are B. burgdorferi. Enzyme-linked immunosorbent assay titers of sera from humans with diagnosed Lyme disease to rabbit tick B. burgdorferi were often similar to one another and to those recorded for a reference B. burgdorferi strain.

Animals↗
PubMed1989

Laboratory analyses for Lyme disease.

Numerous techniques are available for the laboratory diagnosis of Lyme disease. Assays for the detection of antibodies to Borrelia burgdorferi are the most practical means of confirming infection. False positive reactions can occur, but the more serious disadvantages are low sensitivity and lengthy processing time. Nonetheless, serologic tests are being improved and remain valuable research and diagnostic tools. Serologic test results for antibodies to B. burgdorferi should be considered along with clinical data and epidemiological information when evaluating a patient for Lyme disease.

Antibodies, Bacterial↗
PubMed1989

Laboratory diagnosis of Lyme disease.

Different techniques have been developed to aid in laboratory diagnosis of Lyme disease. The detection of serum antibodies, in particular, is relied on heavily by the medical community and is currently the most practical means of confirming B. burgdorferi infections. Although most assays may not detect low amounts of IgM antibody during the initial weeks of infection, application of a capture ELISA method has been reported to improve test sensitivity. Antibodies to Borrelia and Treponema spirochetes will cross-react in conventional assays being used for Lyme disease, but in most cases, these problems can be eliminated by performing other serologic tests or by reviewing clinical and epidemiologic data. Further improvements in the laboratory diagnosis of Lyme disease should be made by standardizing current methods (including commercial test kits), establishing reference laboratories in the United States and Europe, and by developing rapid antigen detection procedures. Finally, serologic determination of B. burgdorferi infections should remain secondary to clinical diagnosis.

Antibodies, Bacterial↗