Ceftriaxone compared with doxycycline for the treatment of acute disseminated Lyme disease

Tick-borne pulmonary disease: update on diagnosis and management

Ticks are capable of transmitting viruses, bacteria, protozoa, and rickettsiae to man. Several of these tick-borne pathogens can lead to pulmonary disease. Characteristic clinical features, such as erythema migrans in Lyme disease, or spotted rash in a spotted fever group disease, may serve as important diagnostic clues. Successful management of tick-borne diseases depends on a high index of suspicion and recognition of their clinical features. Patients at risk for tick bites may be coinfected with two or more tick-borne pathogens. A Lyme vaccine has recently become available for use in the United States. Disease prevention depends on the avoidance of tick bites. When patients present with respiratory symptoms and a history of a recent tick bite or a characteristic skin rash, a differential diagnosis of a tick-borne pulmonary disease should be considered. Early diagnosis and appropriate antibiotic therapy for these disorders lead to greatly improved outcomes.

Borrelia burgdorferi detected by culture and PCR in clinical relapse of disseminated Lyme borreliosis

A total of 165 patients with disseminated Lyme borreliosis (diagnosed in 1990-94, all seropositive except one culture-positive patient) were followed after antibiotic treatment, and 32 of them were regarded as having a clinically defined treatment failure. Of the 165 patients, 136 were tested by polymerase chain reaction (PCR) during the follow-up. PCR was positive from the plasma of 14 patients 0-30 months after discontinuation of the treatment, and 12 of these patients had a clinical relapse. In addition, Borrelia burgdorferi was cultured from the blood of three patients during the follow-up. All three patients belonged to the group with relapse, and two of them were also PCR positive. This report focuses on the 13 patients with clinical relapse and culture or PCR positivity. Eight of the patients had culture or PCR-proven initial diagnosis, the diagnosis of the remaining five patients was based on positive serology only. All 13 patients were primarily treated for more than 3 months with intravenous and/or oral antibiotics (11 of them received intravenous ceftriaxone, nine for 2 weeks, one for 3 weeks and one for 7 weeks, followed by oral antibiotics). The treatment caused only temporary relief in the symptoms of the patients. All but one of them had negative PCR results immediately after the first treatment. The patients were retreated usually with intravenous ceftriaxone for 4-6 weeks. None of them was PCR positive after the retreatment. The response to retreatment was considered good in nine patients. We conclude that the treatment of Lyme borreliosis with appropriate antibiotics for even more than 3 months may not always eradicate the spirochete. By using PCR, it is possible to avoid unnecessary retreatment of patients with 'post-Lyme syndrome' and those with 'serological scars' remaining detectable for months or years after infection.

Neuroborreliosis (Nervous System Lyme Disease)

Treatment of nervous system Lyme disease depends on the severity and site of involvement. Although some data indicate that uncomplicated Lyme meningitis can be treated effectively with oral doxycycline, central nervous system infection (meningitis, radiculitis, encephalomyelitis, and cranial neuritis) is usually treated with parenteral antibiotics for 14 to 30 days, depending on disease severity, as is severe and progressive peripheral nervous system involvement. Ceftriaxone, 2 g/d, is the most commonly used regimen; cefotaxime, 2 g every 8 hours, appears to be equally effective. Penicillin in meningeal doses is also effective, perhaps slightly less so than the third-generation cephalosporins, but it is less convenient to administer. For patients with prohibitive drug allergies, treatment with oral doxycycline in doses of 300 to 400 mg/d may be effective. In patients with facial palsy or with indolent peripheral neuropathies, a trial of oral medication (doxycycline, 100 mg two or three times a day, or amoxicillin, 500 to 1000 mg three times a day for 21 to 30 days) is reasonable. Patients for whom this fails are treated with parenteral medications.

Management of Lyme arthritis

Musculoskeletal complaints and findings can be features of Lyme disease and can occur following treatment. Only with a good understanding of the pathogenesis of these problems can further evaluation and a proper therapeutic scheme be developed.

The cost effectiveness of vaccinating against Lyme disease

To determine the cost effectiveness of vaccinating against Lyme disease, we used a decision tree to examine the impact on society of six key components. The main measure of outcome was the cost per case averted. Assuming a 0.80 probability of diagnosing and treating early Lyme disease, a 0.005 probability of contracting Lyme disease, and a vaccination cost of $50 per year, the mean cost of vaccination per case averted was $4,466. When we increased the probability of contracting Lyme disease to 0.03 and the cost of vaccination to $100 per year, the mean net savings per case averted was $3,377. Since few communities have average annual incidences of Lyme disease >0. 005, economic benefits will be greatest when vaccination is used on the basis of individual risk, specifically, in persons whose probability of contracting Lyme disease is >0.01.

Lyme borreliosis

Lyme borreliosis (Lyme disease) is often said to be associated with "protean" manifestations, a reference to the ancient god Proteus, who could assume many forms and thus elude his pursuers. This legendary quality has clouded our understanding of Lyme borreliosis by giving Borrelia burgdorferi infection a mythical aura of its own. This review shows that this illness, while incompletely understood, is far more palpable than Proteus and is (in most cases) much more readily subdued. The clinical presentations of Lyme borreliosis do differ in North America and Eurasia, possibly due to the differing pathogenicity of distinct genospecies of Borrelia burgdorferi. The most common manifestation, however, in both continents is erythema migrans. Diagnosis should rest on a careful history and objective clinical findings, supported by appropriately chosen laboratory tests. Reports of coinfection with other tick-borne diseases should prompt a fresh look at Lyme borreliosis. Assertions about "protean manifestations" of B burgdorferi infection should be reappraised. Advances in laboratory techniques are welcome but culture remains the gold standard for the diagnosis--and no laboratory test result should substitute for careful clinical observation and critical analysis.

Lyme neuroborreliosis

A broad variability in the clinical manifestations is observed in the European and North American borrelioses. This is dependent on bacterial strain differences in virulence and organotropism, and on different immune responses to Borrelia burgdorferi of the host in these areas. Experimental neuroborreliosis has given insights into mediators and molecular mechanisms of inflammation induced by B. burgdorferi. Histopathological investigations have described the different patterns of injury in the peripheral and central nervous systems. The classic symptoms of neuroborreliosis have been supplemented by new clinical syndromes and neuropsychological investigations. In clinical trials, the efficacy and cost effectiveness of recommended oral and intravenous antibiotic therapies have been compared in early Lyme disease, arthritis and acute disseminated Lyme disease.