Lyme disease: of ticks and titers

Laboratory confirmation of Lyme disease

Lyme disease can be confirmed in the laboratory by isolation or detection of its causative agent, a tick-borne spirochete Borrelia burgdorferi, or by a diagnostic change in the titre of antibodies specific to the agent. B burgdorferi can be isolated and cultivated in Barbour-Stoenner-Kelly II medium. It can be detected by light microscopy in tissue sections or, rarely, in blood smears using various staining methods. There is interest in the development of alternative detection methods, including identification of specific antigens of B burgdorferi in the urine of suspected cases and demonstration of the presence of species-specific DNA using polymerase chain reaction assays. Currently, serological tests (indirect immunofluorescence assay, enzyme-linked immunosorbent assay and Western immunoblot) are the most practical and available methods for confirming Lyme disease. The quest to improve the specificity and sensitivity of serological tests - for example, through the use of specific recombinant antigens - continues.

Physician beliefs, attitudes, and approaches toward Lyme disease in an endemic area

To assess the beliefs and practice habits regarding Lyme disease among practitioners, questionnaires were sent to physicians in a seven-county Lyme-endemic region. One hundred twenty-four evaluable responses were returned from 53 family physicians, 39 pediatricians, 27 internists, and five subspecialists who diagnosed three to four cases of Lyme disease per year, on average. The majority presented with erythema migrans (EM) or other early symptoms, although arthritis was the presenting sign in 16%. The enzyme-linked immunosorbent assay (ELISA) was the most frequently ordered diagnostic test, but 45% of respondents did not specify which test when ordering Lyme serology. The majority would use amoxicillin or doxycycline to treat EM in children or adults, respectively. Nearly all would use ceftriaxone for meningitis, and half would use it to treat Lyme arthritis or Bell's palsy. Physicians differed markedly in the duration of therapy they would prescribe. Eighty-three percent would treat a patient for possible Lyme disease with antibiotics (many intravenously), even in the absence of EM or positive serology. Thirty-five percent of practitioners prescribed antibiotics for deer-tick bites. Our survey documents significant variation in approaches to Lyme disease among primary-care physicians and suggests the need for well-designed clinical trials, continuing basic research, and physician education.

Viral meningitis. Tips to rapidly diagnose treatable causes

Viral meningitis is a common illness among children and is most often caused by enteroviruses. Diagnosis is made on the basis of clinical findings and analysis of the cerebrospinal fluid. Important conditions to consider in diagnosis are partially treated bacterial meningitis, tuberculous meningitis, fungal meningitis, other infections, and central nervous system tumor. Ruling out treatable causes early is important. Treatment of enteroviral meningitis is supportive, and the prognosis is usually very good, although significant neurologic sequelae have been reported.

Epidemiology and clinical manifestations of Lyme borreliosis in childhood. A prospective multicentre study with special regard to neuroborreliosis

Lyme borreliosis is a tick-borne infection caused by the spirochete Borrelia burgdorferi, whose discovery in 1982 solved an aetiological mystery involving a variety of dermatological and neurological disorders and explained their association with Lyme disease. Lyme borreliosis occurs frequently and is readily treatable with antibiotics. Along with its discovery, however, came the realization that it is difficult to diagnose accurately, especially antibody diagnosis. False-positive antibody results in particular led to gradual widening of the clinical spectrum, and differential diagnosis became increasingly difficult. This prospective, multicentre study presents a systematic description of Lyme borreliosis in childhood, emphasizing epidemiological and clinical issues. Because, predominantly, inpatients were examined, Lyme neuroborreliosis was the focus of the study, with the chief concern being to minimize false-positive results. To this end, we chose to narrow the diagnostic criteria, using the presence of specific antibodies in the cerebrospinal fluid as the determining factor. The epidemiological investigation was focused on the incidence of Lyme neuroborreliosis in childhood in southern Lower Saxony as well as on the prevalence of Lyme neuroborreliosis among acute-inflammatory neurological illnesses in children. The clinical part of the study aimed at establishing criteria for differential diagnosis in addition to the detection of specific antibodies. The detection of specific IgM antibodies using an IgM capture ELISA confirmed the presence of acute Lyme borreliosis. The study examined 208 children with Lyme borreliosis, of whom 169 had Lyme neuroborreliosis, from mid-1986 until the end of 1989. The yearly incidence of Lyme neuroborreliosis in Lower Saxony was 5.8 cases/100,000 children aged 1 to 13. The manifestation index was 0.16, or one case of Lyme neuroborreliosis per 620 infected children, compared with the presence of specific antibodies against B. burgdorferi for children in the same age group and region. Both the seasonal distribution of Lyme borreliosis, which peaked in summer and autumn, as well as the information about when the tick bites took place point to an incubation period of a few weeks. The most frequent manifestation of Lyme neuroborreliosis in childhood was acute peripheral facial palsy, found in 55% of all cases (n = 93). Lyme borreliosis proved to be the most frequently verifiable cause of acute peripheral facial palsy in children, causing every second case of this disorder in summer and autumn.(ABSTRACT TRUNCATED AT 400 WORDS)

Usefulness of scanning procedures for diagnosis of fever of unknown origin in children

During a 5-year study period, 109 patients were referred to a large children's hospital for evaluation of prolonged fever of unknown origin, defined as temperature greater than or equal to 38 degrees C (100.4 degrees F) for 3 weeks or longer and negative findings on initial examination. A two-phase protocol of outpatient followed by inpatient diagnostic studies was instituted for most patients. Confirmed diagnoses were achieved in just 36 of these children (33%) in the following disease categories: infectious, 24 (22%); autoimmune, 7 (6%); and neoplastic, 2 (2%). Scanning or special procedures and the number with positive results (in parentheses) were as follows: abdominal ultrasonography, 43 (8); abdominal computed tomography, 14 (3); indium scan 11 (5); gallium scanning, 4 (1), upper gastrointestinal tract series, 13 (2); technetium bone scanning 15 (2); bone marrow examination, 16 (1); and cranial computed tomography, 7 (0). These studies rarely led to an unsuspected diagnosis. It appears most appropriate in evaluating fever of unknown origin in children to obtain only basic laboratory studies such as a complete blood cell count, urinalysis and culture, chest radiograph, tuberculin skin test, and, in the older child, an antinuclear antibody titer. When these test results are negative, almost all children can be observed clinically for progression of illness or a focus that might then direct specific diagnostic procedures.

Lyme disease. Difficulties in diagnosis and management

LB is a multisystem illness caused by the spirochete B. burgdorferi. As with other spirochetal diseases, LB evolves in stages. Some manifestations are the result of persistent infection, whereas other symptoms are a consequence of immunologic changes secondary to the infection. Most disease manifestations are not specific to this illness. In addition, in endemic areas, almost 100% of the tick vector, the Ixodes species, are infected and the incidence rate of LB is as high as 1%. Because of these factors, the illness is overdiagnosed and overtreated. We have reviewed the current state of diagnosis and treatment of LB as well as questions that arise during the management of this illness.

Simultaneous palsy of facial and vestibular nerve in a child with Lyme borreliosis

We describe a boy with borreliosis characterized by lymphocytic meningitis and simultaneous palsy of facial and vestibular nerves on the left side. A mild sensoneural affection was also confirmed by brainstem evoked response audiometry. While symptoms of vestibular dysfunction quickly decreased during antibiotic treatment, facial palsy improved only slowly.