Lyme borreliosis: current issues in diagnosis and management

Dynamics of a periodic tick-borne disease model with co-feeding and multiple patches

By extending a mechanistic model for the tick-borne pathogen systemic transmission with the consideration of seasonal climate impacts, host movement as well as the co-feeding transmission route, this paper proposes a novel modeling framework for describing the spatial dynamics of tick-borne diseases. The net reproduction number for tick growth and basic reproduction number for disease transmission are derived, which predict the global dynamics of tick population growth and disease transmission. Numerical simulations not only verify the analytical results, but also characterize the contribution of co-feeding transmission route on disease prevalence in a habitat and the effect of host movement on the spatial spreading of the pathogen.

Manifestations of Lyme carditis

The first data of Lyme carditis, a relatively rare manifestation of Lyme disease, were published in eighties of the last century. Clinical manifestations include syncope, light-headedness, fainting, shortness of breath, palpitations, and/or chest pain. Atrioventricular (AV) electrical block of varying severity presents the most common conduction disorder in Lyme carditis. Although is usually mild, AV block can fluctuates rapidly and progress from a prolonged P-R interval to a His-Purkinje block within minutes to hours and days. Rarely, Lyme disease may be the cause of endocarditis, while some studies and reports, based on serological and/or molecular investigations, have suggested possible influence of Borrelia burgdorferi on degenerative cardiac valvular disease. Myocarditis, pericarditis, pancarditis, dilated cardiomyopathy, and heart failure have also been described as possible manifestations of Lyme carditis. The clinical course of Lyme carditis is generally mild, short term, and in most cases, completely reversible after adequate antibiotic treatment.

[Diagnosis and treatment of Lyme arthritis. Recommendations of the Pharmacotherapy Commission of the Deutsche Gesellschaft für Rheumatologie (German Society for Rheumatology)]

These guidelines summarize the current evidence for diagnosis and treatment of Lyme arthritis and the most frequent skin manifestations of Borrelia burgdorferi infections. Lyme arthritis is a monoarticular or oligoarticular form of arthritis that typically involves the knee. A positive enzyme-linked immunosorbent assay (ELISA) for IgG antibodies should be followed by an IgG immunoblot. A positive PCR test from synovial fluid adds increased diagnostic certainty. Serum positivity for antibodies to Borrelia burgdorferi without typical symptoms does not justify antibiotic treatment. Oral antibiotic treatment for erythema migrans is recommended using doxycycline, 200 mg once per day for 10-21 days, alternative choices are amoxicillin, cefuroxime and azithromycin. For children below 8 years of age, amoxicillin is recommended.Lyme arthritis can usually be successfully treated with orally administered antimicrobial agents. Doxycycline, 1 × 200 or 2 × 100 mg for 30 days is the antibiotic agent of choice. Amoxicillin (3 × 500-1000 mg) can be alternatively chosen. Patients who have persistent or recurrent joint swelling after a recommended course of oral antibiotic therapy should be treated intravenously. In this situation, ceftriaxone at 2 g per day for 14-21 days is recommended. There is no evidence to recommend long-term and combined treatments.

Lyme arthritis of the pediatric ankle

Lyme arthritis results from acute inflammation caused by the spirochete Borrelia burgdorferi. The number of cases per year has been rising since 2006, with a majority of patients being affected in the northeastern United States. Development of Lyme arthritis is of particular importance to the orthopedic surgeon because Lyme arthritis often presents as an acute episode of joint swelling and tenderness and may be confused with bacterial septic arthritis. Considering the vast difference in treatment management between these 2 pathologies, differentiating between them is of critical importance. Septic arthritis often needs to be addressed surgically, whereas Lyme arthritis can be treated with oral antibiotics alone. Laboratory testing for Lyme disease often results in a delay in diagnosis because many laboratories batch-test Lyme specimens only a few times per week because of increased expense. The authors present a case of Lyme arthritis in the pediatric ankle in an endemic region. No clear algorithm exists to delineate between septic arthritis and Lyme arthritis of the joint. Improved clinical guidelines for the identification and diagnosis of Lyme arthritis of the ankle are important so that appropriate antibiotics can be used and surgery can be avoided.

Bacterial heterogeneity is a requirement for host superinfection by the Lyme disease spirochete

In nature, mixed Borrelia burgdorferi infections are common and possibly can be acquired by either superinfection or coinfection. Superinfection by heterologous B. burgdorferi strains has been established experimentally, although the ability of homologous B. burgdorferi clones to superinfect a host has not been studied in detail. Information regarding any potential immune barriers to secondary infection also currently is unavailable. In the present study, the ability to superinfect various mouse models by homologous wild-type clones was examined and compared to superinfection by heterologous strains. To assess the ability of homologous B. burgdorferi clones to successfully superinfect a mouse host, primary- and secondary-infecting spirochetes were recovered via in vitro cultivation of collected blood or tissue samples. This was accomplished by generating two different antibiotic-resistant versions of the wild-type B31-A3 clone in order to distinguish superinfecting B. burgdorferi from primary-infecting spirochetes. The data demonstrate an inability of homologous B. burgdorferi to superinfect immunocompetent mice as opposed to heterologous strains. Attempts to superinfect different types of immunodeficient mice with homologous B. burgdorferi indicate that the murine innate immune system represents a major barrier to intrastrain superinfection. Consequently, the possibility of innate immunity as a driving force for B. burgdorferi heterogeneity during the enzootic cycle is discussed.

Lyme borreliosis in southern United Kingdom and a case for a new syndrome, chronic arthropod-borne neuropathy

This series of serologically confirmed Lyme disease is the largest reported in the UK and represents 508 patients who presented to one hospital in the South of England between 1992 and 2012. The mean rate of borreliosis throughout this period was 9·8/100,000 population, much higher than the reported national rate of 1·7/100,000. The actual rate increased each year until 2009 when it levelled off. Patients clinically presented with rash (71%), neurological symptoms (16%, of whom half had VII cranial nerve palsies), arthropathy (8%), pyrexia (5%), cardiac abnormalities (1%) or other manifestations (<1%). Twenty percent of patients had additional non-specific symptoms of fatigue, myalgia, and cognitive changes. Serological diagnosis was with a two-tiered system of ELISA and immunoblot. There was a marked seasonal presentation in the summer months and in the first and sixth decades of life. A third of patients gave a clear history of a tick bite. The median interval between tick bite and clinical symptoms was 15 days [interquartile range (IQR) 9-28 days], with a further interval of 14 days to clinical diagnosis/treatment (IQR 2-31 days). Most cases were acquired locally and only 5% abroad. Patients responded to standard antibiotic therapy and recurrence or persistence was extremely rare. A second group of patients, not included in the clinical case series, were those who believed they had Lyme disease based on a probable tick bite but were seronegative by currently available validated tests and presented with subjective symptoms. This condition is often labelled chronic Lyme disease. These patients have a different disease from Lyme disease and therefore an alternative name, chronic arthropod-borne neuropathy (CAN), and case definition for this condition is proposed. We suggest that this chronic condition needs to be distinguished from Lyme disease, as calling the chronic illness 'Lyme disease' causes confusion to patients and physicians. We recommend research initiatives to investigate the aetiology, diagnosis and therapy of CAN.

The use of ivermectin to kill ixodes scapularis ticks feeding on humans

OBJECTIVE

The purpose of this study was to determine whether 400 µg/kg oral ivermectin is able to kill Ixodes scapularis nymphs and adult female ticks feeding on humans.

METHODS

Ten study subjects each wore 2 ostomy bags, the one containing 24 I scapularis nymphs, and the other containing 24 I scapularis adult females. Twenty-four hours after the ostomy bags were attached, study subjects received either 400 µg/kg ivermectin or placebo. Thirty hours after the ivermectin or placebo was consumed, the ticks were removed, and mortality determined in a double-blinded manner.

RESULTS

Eleven percent of the I scapularis nymphs attached in the ivermectin group compared with 17% in the placebo. Mortality for the I scapularis nymphs that attached at the time of removal was 55% in the ivermectin group and 47% in the placebo group. Mortality for the I scapularis nymphs 5 days after removal was 92% in the ivermectin group and 88% for the placebo. Three percent of the I scapularis adults attached in the ivermectin group compared with 9% in the placebo group. Mortality for I scapularis adults was 0% on day 3 and 33% on day 8 for both the ivermectin and placebo groups. There were statistically insignificant differences in the mortality rates between I scapularis nymphs and adults exposed to ivermectin or placebo.

CONCLUSIONS

There were a high number of ticks that died in both groups but the data do not support our hypothesis that ivermectin can kill I scapularis. The study was not designed to determine whether it could prevent the transmission of tick-borne illness.

Intraarticular corticosteroids in refractory childhood Lyme arthritis

Lyme arthritis caused by infection with Borrelia burgdorferi is a common late manifestation of Lyme borreliosis. Current treatment recommendations include at least one oral or intravenous antibiotic course, followed by antirheumatic therapy in case of refractory arthritis. We reviewed the course of 31 children with Lyme arthritis who had received antibiotic treatment and assessed outcome and requirement of antirheumatic therapy. Of a total of 31 patients, 23 (74%) showed complete resolution of arthritis after one or two courses of antibiotics, whereas in 8 patients (28%), steroid injections had been performed due to relapsing or remaining symptoms. All of these 8 patients showed immediate resolution of symptoms after intraarticular steroid injections. Four of them (50%) remained asymptomatic so far with a follow-up period between five up to 40 months. In two cases, multiple intraarticular corticosteroid injections were required; three patients received additional or consecutive treatment with systemic antirheumatic treatment. Patients with antibiotic refractory arthritis showed a higher rate of positivity of the IgG p58 and OspC immunoblot bands (p = 0.05) at presentation. Antibodies against OspA, an indicator of later stage infection, occurred more frequently in the refractory group without reaching significant level. No clinical marker as indicator for severe or prolonged course of Lyme arthritis was identifiable. A quarter of childhood Lyme arthritis patients were refractory to antibiotics and required antirheumatic treatment. Intraarticular steroid injections in childhood Lyme arthritis refractory to antibiotics can lead to marked clinical improvement.

Bakterielle Infektionen: Atypische Bakterien

Chlamydophila (früher Chlamydia) pneumoniae ist im Kindesalter ein seltener Erreger respiratorischer Infektionen, vor allem der Pneumonie, wenn die PCR als direkte Nachweismethode herangezogen wird. Die höhere Nachweisrate von Antikörpern gegen C. pneumoniae deutet auf eine hohe Rate asymptomatischer oder unspezifischer Infektionen durch C. pneumoniae hin.

Der Mensch ist weltweit das einzige Erregerreservoir. Kranke, seltener auch asymptomatische Ausscheider (Wochen bis 1 Jahr) sind die Ansteckungsquelle. Die Übertragung erfolgt als „Tröpfcheninfektion“ mit respiratorischen Sekreten. Eine epidemische Krankheitshäufung ist beschrieben. In feuchtem Milieu können Chlamydien bis zu 30 h auf unbelebtem Material überleben.

Im Erwachsenenalter haben 50–75 % der Bevölkerung Antikörper gegen C. pneumoniae. Die höchsten Titer werden in der Altersklasse der 5- bis 14-Jährigen gefunden – ein Indiz für das Hauptmanifestationsalter der Primärinfektion. Seroprävalenzdaten aus Deutschland decken sich mit den Angaben aus der internationalen Literatur (5 % der unter 10-Jährigen, 64 % der unter 18-Jährigen besitzen Antikörper gegen C. pneumoniae). Ambulant erworbene Pneumonien werden im Kindesalter möglicherweise in bis zu 18 % der Fälle (serologische Diagnose) durch C. pneumoniae verursacht. Untersuchungen mittels PCR hingegen weisen C. pneumoniae nur in sporadischen Fällen nach. Koinfektionen mit Mykoplasmen, aber auch Pneumokokken und Adenoviren sind keine Seltenheit.

Experience of Lyme disease and preferences for precautions: a cross-sectional survey of UK patients

BACKGROUND

Lyme disease (LD) is a tick-borne zoonosis currently affecting approximately 1000 people annually in the UK (confirmed through serological diagnosis) although it is estimated that the real figures may be as high as 3000 cases. It is important to know what factors may predict correct appraisal of LD symptoms and how the experience of LD might predict preferences for future precautionary actions.

METHODS

A cross-sectional survey was conducted with early LD patients via the Lyme Borreliosis Unit at the Health Protection Agency. One hundred and thirty participants completed measures of awareness of having been bitten by ticks, knowledge of ticks and LD, interpretation of LD symptoms, suspicions of having LD prior to seeing the General Practitioner (GP), and preferences for precautionary actions during future countryside visits. Chi-square tests and logistic regression were used to identify key predictors of awareness of having been bitten by ticks and of having LD. t-tests assessed differences between groups of participants on suspicions of having LD and preferences for future precautions. Pearson correlations examined relationships between measures of preferences for precautions and frequency of countryside use, knowledge of ticks and LD, and intentions to avoid the countryside in the future.

RESULTS

73.8% of participants (n = 96) reported a skin rash as the reason for seeking medical help, and 44.1% (n = 64) suspected they had LD before seeing the GP. Participants reporting a direct event in realizing they had been bitten by ticks (seeing a tick on skin or seeing a skin rash and linking it to tick bites) were more likely to suspect they had LD before seeing the doctor. Participants distinguished between taking precautions against tick bites during vs. after countryside visits, largely preferring the latter. Also, the more frequently participants visited the countryside, the less likely they were to endorse during-visit precautions.

CONCLUSIONS

The results suggest that the risk of LD is set in the context of the restorative benefits of countryside practices, and that it may be counterproductive to overemphasize pre- or during-visit precautions. Simultaneously, having experienced LD is not associated with any withdrawal from countryside.

Central Nervous System Infections

Central nervous system (CNS) infections—i.e., infections involving the brain (cerebrum and cerebellum), spinal cord, optic nerves, and their covering membranes—are medical emergencies that are associated with substantial morbidity, mortality, or long-term sequelae that may have catastrophic implications for the quality of life of affected individuals. Acute CNS infections that warrant neurointensive care (ICU) admission fall broadly into three categories—meningitis, encephalitis, and abscesses—and generally result from blood-borne spread of the respective microorganisms. Other causes of CNS infections include head trauma resulting in fractures at the base of the skull or the cribriform plate that can lead to an opening between the CNS and the sinuses, mastoid, the middle ear, or the nasopharynx. Extrinsic contamination of the CNS can occur intraoperatively during neurosurgical procedures. Also, implanted medical devices or adjunct hardware (e.g., shunts, ventriculostomies, or external drainage tubes) and congenital malformations (e.g., spina bifida or sinus tracts) can become colonized and serve as sources or foci of infection. Viruses, such as rabies, herpes simplex virus, or polioviruses, can spread to the CNS via intraneural pathways resulting in encephalitis. If infection occurs at sites (e.g., middle ear or mastoid) contiguous with the CNS, infection may spread directly into the CNS causing brain abscesses; alternatively, the organism may reach the CNS indirectly via venous drainage or the sheaths of cranial and spinal nerves. Abscesses also may become localized in the subdural or epidural spaces. Meningitis results if bacteria spread directly from an abscess to the subarachnoid space. CNS abscesses may be a result of pyogenic meningitis or from septic emboli associated with endocarditis, lung abscess, or other serious purulent infections. Breaches of the blood–brain barrier (BBB) can result in CNS infections. Causes of such breaches include damage (e.g., microhemorrhage or necrosis of surrounding tissue) to the BBB; mechanical obstruction of microvessels by parasitized red blood cells, leukocytes, or platelets; overproduction of cytokines that degrade tight junction proteins; or microbe-specific interactions with the BBB that facilitate transcellular passage of the microorganism. The microorganisms that cause CNS infections include a wide range of bacteria, mycobacteria, yeasts, fungi, viruses, spirochaetes (e.g., neurosyphilis), and parasites (e.g., cerebral malaria and strongyloidiasis). The clinical picture of the various infections can be nonspecific or characterized by distinct, recognizable clinical syndromes. At some juncture, individuals with severe acute CNS infections require critical care management that warrants neuro-ICU admission. The implications for CNS infections are serious and complex and include the increased human and material resources necessary to manage very sick patients, the difficulties in triaging patients with vague or mild symptoms, and ascertaining the precise cause and degree of CNS involvement at the time of admission to the neuro-ICU. This chapter addresses a wide range of severe CNS infections that are better managed in the neuro-ICU. Topics covered include the medical epidemiology of the respective CNS infection; discussions of the relevant neuroanatomy and blood supply (essential for understanding the pathogenesis of CNS infections) and pathophysiology; symptoms and signs; diagnostic procedures, including essential neuroimaging studies; therapeutic options, including empirical therapy where indicated; and the perennial issue of the utility and effectiveness of steroid therapy for certain CNS infections. Finally, therapeutic options and alternatives are discussed, including the choices of antimicrobial agents best able to cross the BBB, supportive therapy, and prognosis.

Detecting Lyme disease using antibody-functionalized single-walled carbon nanotube transistors

We examined the potential of antibody-functionalized single-walled carbon nanotube (SWNT) field-effect transistors (FETs) to use as a fast and accurate sensor for a Lyme disease antigen. Biosensors were fabricated on oxidized silicon wafers using chemical vapor deposition grown carbon nanotubes that were functionalized using diazonium salts. Attachment of Borrelia burgdorferi (Lyme) flagellar antibodies to the nanotubes was verified by atomic force microscopy and electronic measurements. A reproducible shift in the turn-off voltage of the semiconducting SWNT FETs was seen upon incubation with B. burgdorferi flagellar antigen, indicative of the nanotube FET being locally gated by the residues of flagellar protein bound to the antibody. This sensor effectively detected antigen in buffer at concentrations as low as 1 ng/ml, and the response varied strongly over a concentration range coinciding with levels of clinical interest. Generalizable binding chemistry gives this biosensing platform the potential to be expanded to monitor other relevant antigens, enabling a multiple vector sensor for Lyme disease. The speed and sensitivity of this biosensor make it an ideal candidate for development as a medical diagnostic test.

Misleading presentation of acute Lyme neuroborreliosis

A young man presented with recent-onset non-specific symptoms like headache, sleepiness and weight loss, interfering with normal daily life. Physical and biochemical irregularities were absent. Because extensive examination by neurologist and psychiatrist including brain imaging did not reveal any clues, the complaints were initially considered psychosomatic. As the symptoms deteriorated with ongoing weight loss, the patient was re-admitted to the hospital. Again, extensive additional investigation did not reveal any abnormalities. Because of previous exposition to the woods Lyme serology was determined. Surprisingly, it appeared to be a remarkable presentation of acute Lyme neuroborreliosis which was successfully treated with ceftriaxon. Clinicians must be aware of the fact that this severe illness can present without any typical symptoms.

Initial assessment of the ability of ivermectin to kill Ixodes scapularis and Dermacentor variabilis ticks feeding on humans

OBJECTIVE

The purpose of this study was to determine Ixodes scapularis and Dermacentor variabilis tick mortality when fed on humans who have consumed 400 μg/kg oral ivermectin.

METHODS

Six study subjects, 3 in each group, were randomly assigned to receive either 400 μg/kg ivermectin or placebo in a blinded manner. After consuming either ivermectin or placebo, each study subject had 2 colostomy bags attached to his or her abdomen. One of the colostomy bags contained 7 I scapularis nymphs and 7 adults. The other colostomy bag contained 7 D variabilis nymphs and 7 adults. Tick mortality was recorded over the next 24 hours.

RESULTS

Fifty-five percent (6 of 11) of the attached I scapularis nymphs exposed to ivermectin had morbidity (3 of 11) or died (3 of 11), compared with 0% morbidity and mortality in the 2 I scapularis nymphs that attached in the placebo group. No I scapularis adults or D variabilis nymphs attached to feed. Among D variabilis adults that attached to feed, there was a 0% mortality rate for both the placebo group (0 of 6) and the ivermectin group (0 of 8).

CONCLUSIONS

We demonstrate a novel method to confine ticks to human subjects to study tick-borne diseases. While there was a trend toward I scapularis morbidity and mortality in the ivermectin arm, the low number of ticks that attached in the placebo group limited our analysis. Most ticks began feeding in the last 12 hours of the experiment, significantly limiting their exposure to ivermectin. Ivermectin does not cause early death in D variabilis adults.

Long-term clinical outcome after Lyme neuroborreliosis in childhood

OBJECTIVES

To determine long-term clinical outcome in children with confirmed Lyme neuroborreliosis (LNB) and to evaluate persistent subjective symptoms compared with a control group.

METHODS

After a median of 5 years, 84 children with confirmed LNB underwent a neurologic re-examination, including a questionnaire. Medical records were analyzed, and a control group (n = 84) was included.

RESULTS

The total recovery rate was 73% (n = 61). Objective neurologic findings, defined as "definite sequelae," were found in 16 patients (19%). The majority of these children had persistent facial nerve palsy (n = 11), but other motor or sensory deficits occurred (n = 5). Neurologic signs and/or symptoms defined as "possible sequelae" were found in another 7 patients (8%), mainly of sensory character. Nonspecific subjective symptoms were reported by 35 patients (42%) and 32 controls (38%) (nonsignificant). Affected daily activities or school performance were reported to the same extent in both groups (23% vs 20%, nonsignificant).

CONCLUSIONS

The long-term clinical recovery rate was 73% in children with confirmed LNB. Persistent facial nerve palsy occurred in 13%, whereas other motor or sensory deficits were found in another 14%. Neurologic deficits did not affect daily activities or school performance more often among patients than controls and should be considered as mild. Furthermore, nonspecific subjective symptoms such as headache, fatigue, or memory or concentration problems were reported as often among patients as controls and should not be considered as sequelae after LNB.

Lyme disease in a British referral clinic

BACKGROUND

Concerns about over-diagnosis and inappropriate management of Lyme disease (LD) are well documented in North America and supported by clinical data. There are few parallel data on the situation in the UK.

AIM

To describe the patterns of referral, investigation, diagnosis and treatment of patients with suspected LD referred to an infectious disease unit in Liverpool, UK. Previous management by National Health Service (NHS) and non-NHS practitioners was reviewed.

DESIGN

Descriptive study conducted by retrospective casenotes review.

METHODS

Retrospective casenotes review of adults referred with possible LD to an infectious disease unit in Liverpool, UK, over 5 years (2006-2010).

RESULTS

Of 115 patients, 27 (23%) were diagnosed with LD, 38 (33%) with chronic fatigue syndrome (CFS) and 13 (11%) with other medical conditions. No specific diagnosis could be made in 38 (33%). At least 53 unnecessary antibiotic courses had been given by non-NHS practitioners; 21 unnecessary courses had been prescribed by NHS practitioners. Among 38 patients, 17 (45%) with CFS had been misdiagnosed as having LD by non-NHS practitioners.

CONCLUSION

A minority of referred patients had LD, while a third had CFS. LD is over-diagnosed by non-specialists, reflecting the complexities of clinical and/or laboratory diagnosis. Patients with CFS were susceptible to misdiagnosis in non-NHS settings, reinforcing concerns about missed opportunities for appropriate treatment for this group and about the use of inappropriate diagnostic modalities and anti-microbials in non-NHS settings.

Outpatient parenteral antimicrobial therapy with ceftriaxone, a review

BACKGROUND

More than 30 years since it was developed for clinical use, the third-generation cephalosporin ceftriaxone remains the most commonly used agent for outpatient parental antimicrobial therapy (OPAT). Recent antimicrobial stewardship programmes have tended to restrict ceftriaxone use in hospitals to control antibiotic resistance and outbreaks of Clostridium difficle infection (CDI). Considering the expansion of OPAT programmes both in the UK and worldwide, revisiting the role of ceftriaxone in OPAT in the context of changing antimicrobial prescribing practices is timely.

AIM OF THE REVIEW

To identify the evidence base for OPAT, review current and historical data on indications for, and safety of ceftriaxone within the OPAT setting, and to provide some perspectives on the future role of ceftriaxone.

METHOD

We searched PubMed and Scopus for articles published in English, and hand searched reference lists. We also conducted a complementary descriptive analysis of prospectively acquired data on the use of ceftriaxone in more than 1,300 OPAT episodes over a 10-year period in our UK centre.

RESULTS

Ceftriaxone has an excellent safety profile in the OPAT setting, and its broad spectrum of activity makes it an established agent in a wide range of clinical infection syndromes, such as skin and soft-tissue infection, bone and joint infection, streptococcal endocarditis and several others. Intriguingly, in contrast to the inpatient setting, liberal use of ceftriaxone in OPAT has not been strongly linked to CDI, suggesting additional patient and environmental factors may be important in mediating CDI risk.

Primary lyme arthritis of the pediatric hip

BACKGROUND

Lyme arthritis most commonly affects the knee. It is not commonly considered in the differential diagnosis of monoarticular hip pain. There are only a few case reports describing Lyme disease presenting with isolated hip involvement. The purpose of this study is to review our experience with primary Lyme arthritis of the hip.

METHODS

Clinical records at a tertiary children's referral center in a Lyme endemic region were scanned for key words "Lyme" and "hip." Patients with isolated Lyme disease of the hip were included. Diagnosis was made based on Centers for Disease Control guidelines. Clinical presentation, laboratory evaluation, and treatment information were recorded for eligible patients.

RESULTS

Eight patients met eligibility criteria with an average age of 9.5 years (3 to 20y). All patients presented with hip pain (8), limp (3), or refusal to bear weight (5). One of 8 patients had a fever >38.5°C. Two of 8 patients had a peripheral white blood cell count >12,500/mm and 3 of 8 patients had an erythrocyte sedimentation rate>40 mm/h. Aspiration was performed on 5 patients, with a median synovial fluid white blood cell of 41,500/mm (21,500 to 73,500/mm). Three of 8 patients were treated surgically; all patients were treated with antibiotics and were asymptomatic at last follow-up. With the exception of 1 case, there was a delay before appropriate antibiotics were started.

CONCLUSIONS

Primary monoarticular Lyme arthritis of the hip is uncommon. Clinical presentation and laboratory findings are variable, and differentiating it from septic arthritis or toxic synovitis of the hip may be difficult. In areas where Lyme disease is endemic, it should be considered in the differential diagnosis of monoarticular hip pain associated with an effusion.

LEVEL OF EVIDENCE

Level IV, Case Series.

Validation of a clinical prediction rule to distinguish Lyme meningitis from aseptic meningitis

OBJECTIVES

The "Rule of 7's," a Lyme meningitis clinical prediction rule, classifies children at low risk for Lyme meningitis when each of the following 3 criteria are met: <7 days of headache, <70% cerebrospinal fluid (CSF) mononuclear cells, and absence of seventh or other cranial nerve palsy. The goal of this study was to test the performance of the Rule of 7's in a multicenter cohort of children with CSF pleocytosis.

METHODS

We performed a retrospective cohort study of children evaluated at 1 of 3 emergency departments located in Lyme disease-endemic areas with CSF pleocytosis and Lyme serology obtained. Lyme meningitis was defined using the Centers for Disease Control and Prevention criteria (either positive Lyme serology test result or an erythema migrans [EM] rash). We calculated the performance of the Rule of 7's in our overall study population and in children without physician-documented EM.

RESULTS

We identified 423 children, of whom 117 (28% [95% confidence interval (CI): 24%-32%]) had Lyme meningitis, 306 (72% [95% CI: 68%-76%]) had aseptic meningitis, and 0 (95% CI: 0%-1%) had bacterial meningitis. Of the 130 classified as low risk, 5 had Lyme meningitis (sensitivity, 112 of 117 [96% (95% CI: 90%-99%)]; specificity, 125 of 302 [41% (95% CI: 36%-47%)]). In the 390 children without EM, 3 of the 127 low-risk patients had Lyme meningitis (2% [95% CI: 0%-7%]).

CONCLUSIONS

Patients classified as low risk by using the Rule of 7's were unlikely to have Lyme meningitis and could be managed as outpatients while awaiting results of Lyme serology tests.

Clinical, diagnostic and immunological characteristics of patients with possible neuroborreliosis without intrathecal Ig-synthesis against Borrelia antigen in the cerebrospinal fluid

The diagnosis of neuroborreliosis is not always straightforward. Intrathecal immunoglobulin (Ig) synthesis against Borrelia antigen may not be detected, at least early in the disease course. Also other neurological and infectious diagnoses have to be considered. We have studied patients with clinical possible neuroborreliosis without intrathecal Ig synthesis against Borrelia antigen in the cerebrospinal fluid (CSF) (n=17). Diagnosis was based on typical clinical history and at least one of the following findings; mononuclear leucocytosis in the CSF (n=4); typical erythema migrans >5 cm in diameter in relation to debut of symptoms (n=8); prompt clinical response to antibiotic teratment (n=14). Also other possible diagnoses had to be excluded. Seventeen patients first investigated because of suspected neuroborreliosis but later confirmed with other diagnoses were used as controls. All patients had a lumbar puncture. Borrelia specific IFN-γ and IL-4 secretion was investigated in peripheral blood (PBL) and CSF with an ELISPOT assay. Polymerase chain reaction (PCR) was used to reveal any Borrelia antigen in the CSF. Six of 17 patients with possible neuroborreliosis showed high IFN-γ secretion in peripheral blood, otherwise we found no statistically significant differences between the groups. PCR did not reveal any Borrelia antigen in CSF. The diagnosis and treatment of possible but not confirmed neuroborreliosis is a clinical challenge. The clinical response to treatment may be the best option in these cases.