Cutaneous borreliosis in children - a challenging problem.

Borreliosis, also known as Lyme disease, is a vector-borne disease caused by different species of the Borrelia burgdorferi complex. It is frequent in Europe and Northern America. The major vectors are ixodoid ticks. Paediatric borreliosis is common and peaks in children between five to nine years. In Europe, the leading symptom of early infection is erythema migrans, in contrast to Northern America where arthritis is the dominating clinical finding. In this review, we focus on Europe, where cutaneous borreliosis is mainly caused by infection with B. afzelii. The cutaneous symptoms include erythema migrans, lymphocytoma, chronic atrophic dermatitis and juxta-articular nodules. In children, lymphocytoma is very common but chronic atrophic dermatitis is rare. Clinical symptoms, diagnosis, peculiarities of childhood disease and treatment are also reviewed. It is important to note that after haematogeneic spread, signs of infection may be non-specific, and this is a challenge for diagnosis.

Annexin A2 antibodies in post-treatment Lyme disease.

Background: Anti-annexin A2 (AA2) antibodies have been described in Lyme arthritis and erythema migrans, although they have not been described in post-treatment Lyme disease (PTLD). Objectives: Determine whether anti-AA2 antibodies are present among patients with PTLD and determine the clinical relevance of these antibodies. Design and methods: Anti-AA2 levels were tested serially in a longitudinal cohort of 44 patients with acute Lyme disease, 22 with a return to health (EM RTH), and 22 with PTLD. Anti-AA2 antibodies were also assessed in a cross-sectional group of 281 patients with PTLD. Results: Anti-AA2 antibodies were highest after antimicrobial therapy in both the EM RTH and PTLD cohorts. By 6 months, there was no difference between EM RTH and healthy controls. Anti-AA2 antibodies were higher in the cross-sectional PTLD group (79.69 versus 48.22 units, p < 0.0001), though with no difference in total symptom burden. Conclusion: Anti-AA2 persists in PTLD, though did not identify a clinical phenotype.

Treatment of post-treatment Lyme disease symptoms-a systematic review.

BACKGROUND AND PURPOSE: Residual symptoms after treatment of Lyme disease, sometimes called post-treatment Lyme disease symptoms (PTLDs), are a matter of ongoing controversy. To guide treatment recommendations, a systematic review was performed of the available literature on specific treatment for PTLDs. METHODS: A systematic literature search of MEDLINE and CENTRAL was performed. No restrictions on case definitions, study types or specific interventions were applied to enable a comprehensive overview of the available literature. Risk of bias was assessed using the Cochrane risk of bias tools for randomized controlled trials. Certainty of the evidence was assessed using the Grading of Recommendations, Assessment, Development and Evaluation approach. Outcomes of interest were quality of life, fatigue, depression and cognition as well as adverse events. RESULTS: After screening 1274 records, eight eligible randomized controlled trials were included. Heterogeneity was observed regarding inclusion criteria, intervention, length of treatment and outcome measures. For efficacy outcomes, results are presented narratively due to heterogeneity. Eligible studies show no statistically significant difference between antibiotics and placebo regarding quality of life, cognition and depression. Results for fatigue were inconsistent whilst studies with low risk of bias showed no statistically significant difference between antibiotics and placebo. Meta-analysis of safety outcomes showed statistically significantly more adverse events for antibiotics compared to placebo. CONCLUSIONS: Available literature on treatment of PTLDs is heterogeneous, but overall shows evidence of no effect of antibiotics regarding quality of life, depression, cognition and fatigue whilst showing more adverse events. Patients with suspected PTLDs should not be treated with antibiotics.

Performance of two modified two-tier algorithms for the serologic diagnosis of Lyme disease.

We compared the performance of a new modified two-tier testing (MTTT) platform, the Diasorin Liaison chemiluminescent immunoassay (CLIA), to the Zeus enzyme-linked immunoassay (ELISA) MTTT and to Zeus ELISA/Viramed immunoblot standard two-tier testing (STTT) algorithm. Of 537 samples included in this study, 91 (16.9%) were positive or equivocal by one or more screening tests. Among these 91 samples, only 57 samples were concordant positive by first-tier screening tests, and only 19 of 57 were concordant by the three second-tier methods. For IgM results, positive percent agreement (PPA) was 68.1% for Diasorin versus 89.4% for Zeus compared to immunoblot. By contrast, the PPA for IgG for both Diasorin and Zeus was 100%. Using a 2-out-of-3 consensus reference standard, the PPAs for IgM were 75.6%, 97.8%, and 95.6% for Diasorin, Zeus, and immunoblot, respectively. The difference between Zeus MTTT and Diasorin MTTT for IgM detection was significant (P = 0.0094). PPA for both Diasorin and Zeus MTTT IgG assays was 100% but only 65.9% for immunoblot STTT (P = 0.0005). In total, second-tier positive IgM and/or IgG results were reported for 57 samples by Diasorin MTTT, 63 by Zeus MTTT, and 54 by Viramed STTT. While Diasorin CLIA MTTT had a much more rapid, automated, and efficient workflow, Diasorin MTTT was less sensitive for the detection of IgM than Zeus MTTT and STTT including in 5 early Lyme cases that were IgM negative but IgG positive. IMPORTANCE: The laboratory diagnosis of Lyme disease relies upon the detection of antibodies to Borrelia species. Standard two tier testing (STTT) methods rely upon immunoblots which have clinical and technical limitations. Modified two-tier testing (MTTT) methods have recently become available and are being widely adopted. There are limited independent data available assessing the performance of MTTT and STTT methods.

Tick-Borne Diseases.

Ticks are responsible for the vast majority of vector-borne illnesses in the United States. The number of reported tick-borne disease (TBD) cases has more than doubled in the past 20 years. The majority of TBD cases occur in warm weather months in individuals with recent outdoor activities in wooded areas. The risk of contracting a TBD is also highly dependent on geographic location. Between 24 and 48 hours of tick attachment is required for most disease transmission to occur. Only 50% to 70% of patients with a TBD will recall being bitten by a tick, and TBDs are often initially misdiagnosed as a viral illness. Most TBDs are easily treated when diagnosed early in their course.

Evaluation and 1-year follow-up of patients presenting at a Lyme borreliosis expertise centre: a prospective cohort study with validated questionnaires.

OBJECTIVES: To describe the course of symptoms reported by patients with symptoms attributed to Lyme borreliosis (LB) without being subsequently diagnosed with LB. METHODS: We performed a prospective cohort study with patients presenting at the outpatient clinic of two clinical LB centres. The primary outcome was the prevalence of persistent symptoms, which were defined as clinically relevant fatigue (CIS, subscale fatigue), pain (SF-36, subscale bodily pain), and cognitive impairment (CFQ) for ≥ 6 months and onset < 6 months over the first year of follow-up. Outcomes were compared with a longitudinal cohort of confirmed LB patients and a general population cohort. Prevalences were standardised to the distribution of pre-defined confounders in the confirmed LB cohort. RESULTS: Participants (n = 123) reported mostly fatigue, arthralgia, myalgia, and paraesthesia as symptoms. The primary outcome could be determined for 74.8% (92/123) of participants. The standardised prevalence of persistent symptoms in our participants was 58.6%, which was higher than in patients with confirmed LB at baseline (27.2%, p < 0.0001) and the population cohort (21.2%, p < 0.0001). Participants reported overall improvement of fatigue (p < 0.0001) and pain (p < 0.0001) but not for cognitive impairment (p = 0.062) during the follow-up, though symptom severity at the end of follow-up remained greater compared to confirmed LB patients (various comparisons p < 0.05). CONCLUSION: Patients with symptoms attributed to LB who present at clinical LB centres without physician-confirmed LB more often report persistent symptoms and report more severe symptoms compared to confirmed LB patients and a population cohort.

Knowledge, protective behaviours, and perception of Lyme disease in an area of emerging risk: results from a cross-sectional survey of adults in Ottawa, Ontario.

BACKGROUND: The number of Lyme disease risk areas in Canada is growing. In regions with emerging tick populations, it is important to emphasize peridomestic risk and the importance of protective behaviours in local public health communication. This study aims to identify characteristics associated with high levels of Lyme disease knowledge and adoption of protective behaviours among residents in the Ottawa, Ontario region. METHODS: A geographically stratified web survey was conducted in November 2020 (n = 2018) to determine knowledge, attitudes, and practices regarding Lyme disease among adult residents. Responses were used to calculate: (i) composite scores for knowledge and adoption of protective practices; and (ii) an exposure risk index based on reported activity in woodlands during the spring-to-fall tick exposure risk period. RESULTS: 60% of respondents had a high knowledge of Lyme disease, yet only 14% indicated they often use five or more measures to protect themselves. Factors strongly associated with a high level of Lyme disease knowledge included being 55 or older (Odds Ratio (OR) = 2.04), living on a property with a yard (OR = 3.22), having a high exposure index (OR = 1.59), and knowing someone previously infected with Lyme disease (OR = 2.05). Strong associations with the adoption of a high number of protective behaviours were observed with membership in a non-Indigenous racialized group (OR = 1.70), living on a property with a yard (OR = 2.37), previous infection with Lyme disease (OR = 2.13), prior tick bite exposure (OR = 1.62), and primarily occupational activity in wooded areas (OR = 2.31). CONCLUSIONS: This study highlights the dynamics between Lyme disease knowledge, patterns of exposure risk awareness, and vigilance of personal protection in a Canadian region with emerging Lyme disease risk. Notably, this study identified gaps between perceived local risk and protective behaviours, presenting opportunities for targeted enhanced communication efforts in areas of Lyme disease emergence.

Shorter versus longer duration of antimicrobial therapy for early Lyme disease: A systematic review and meta-analysis.

BACKGROUND: Antibiotic therapy for patients with early Lyme disease is necessary to prevent later-stage Lyme disease complications. This systematic review and meta-analysis compares shorter versus longer antibiotic regimens in treating early Lyme disease. METHODS: A systematic search of PubMed, Embase, and Cochrane Central Register of Controlled Trials was conducted up to November 2023. We examined treatment failure, complete response, and photosensitivity. Short vs. long therapy was defined as ≤10 days vs. >10 days. Subgroup analyses included antibiotic type and varying treatment durations. Analysis utilized RStudio 4.1.2. PROSPERO registration: CRD42023423876. RESULTS: Seven studies, encompassing 1,462 patients, were analyzed. No significant differences in treatment failure, 12-month complete response, final visit complete response were found between short and long durations of antibiotic therapy. Subgroup and sensitivity analyses corroborated these findings. CONCLUSION: Shorter and longer antibiotic regimens for early Lyme disease show similar efficacy, highlighting the potential of ≤10-day courses, as effective treatment options.

An Unusual Case of Serologically Confirmed Post-Partum Lyme Disease Following an Asymptomatic Borrelia burgdorferi Infection Acquired during Pregnancy and Lacking Vertical Transmission in Utero.

In this report, we describe a 23-year-old female who, while pregnant, was exposed to Borrelia burgdorferi but did not develop significant signs or symptoms (joint pain, arthritis) of Lyme disease until shortly after delivering a healthy child at term. Serologic testing confirmed infection with B. burgdorferi. A 3-week course of treatment with doxycycline was completely curative. There was no evidence for congenital or perinatal transmission of this pathogen at any point pre-term or postnatally. The key reasons that could account for this unique clinical scenario are discussed in the context of previously published related reports.

The molecular determinants of classical pathway complement inhibition by OspEF-related proteins of Borrelia burgdorferi.

The complement system serves as the first line of defense against invading pathogens by promoting opsonophagocytosis and bacteriolysis. Antibody-dependent activation of complement occurs through the classical pathway and relies on the activity of initiating complement proteases of the C1 complex, C1r and C1s. The causative agent of Lyme disease, Borrelia burgdorferi, expresses two paralogous outer surface lipoproteins of the OspEF-related protein family, ElpB and ElpQ, that act as specific inhibitors of classical pathway activation. We have previously shown that ElpB and ElpQ bind directly to C1r and C1s with high affinity and specifically inhibit C2 and C4 cleavage by C1s. To further understand how these novel protease inhibitors function, we carried out a series of hydrogen-deuterium exchange mass spectrometry (HDX-MS) experiments using ElpQ and full-length activated C1s as a model of Elp/protease interaction. Comparison of HDX-MS profiles between unbound ElpQ and the ElpQ/C1s complex revealed a putative C1s-binding site on ElpQ. HDX-MS-guided, site-directed ElpQ mutants were generated and tested for direct binding to C1r and C1s using surface plasmon resonance. Several residues within the C-terminal region of ElpQ were identified as important for protease binding, including a single conserved tyrosine residue that was required for ElpQ- and ElpB-mediated complement inhibition. Collectively, our study identifies key molecular determinants for classical pathway protease recognition by Elp proteins. This investigation improves our understanding of the unique complement inhibitory mechanism employed by Elp proteins which serve as part of a sophisticated complement evasion system present in Lyme disease spirochetes.

Prevalence of Powassan Virus Seropositivity Among People with History of Lyme Disease and Non-Lyme Community Controls in the Northeastern United States.

Introduction: Lyme disease (LD) affects ∼476,000 people each year in the United States. Symptoms are variable and include rash and flu-like symptoms. Reasons for the wide variation in disease outcomes are unknown. Powassan virus (POWV) is a tick-borne flavivirus that causes disease ranging from asymptomatic infection to encephalitis, neurologic damage, and death. POWV and LD geographic case distributions overlap, with Ixodes species ticks as the common vectors. Clinical ramifications of coinfection or sequential infection are unknown. Objectives: This study's primary objective was to determine the prevalence of POWV-reactive antibodies in sera samples collected from previously studied cohorts of individuals with self-reported LD history residing in the Northeastern United States. As a secondary objective, we studied clinical differences between people with self-reported LD history and low versus high POWV antibody levels. Methods: We used an enzyme-linked immunosorbent assay (ELISA) to quantify IgG directed at the POWV envelope (E) protein domain III in 538 samples from individuals with self-reported LD history and 16 community controls. The samples were also tested with an ELISA assay to quantify IgG directed at the POWV NS1 protein. Results: The percentage of individuals with LD history and possible evidence of POWV exposure varied depending on the assay utilized. We found no significant difference in clinical symptoms between those with low or high POWV IgG levels in the in-house assay. Congruence of the EDIII and NS1 assays was low with only 12% of those positive in the in-house EDIII ELISA testing positive in the POWV NS1 ELISA. Conclusions: The results highlight the difficulty in flavivirus diagnostic testing, particularly in the retrospective detection of flavivirus exposure. The findings suggest that a prospective study with symptomatic patients using approved clinical testing is necessary to address the incidence and clinical implications of LD and POWV co-infection or sequential infection.

Seroprevalence of Infection by Borrelia Species Responsible for Lyme Disease in the French Alps: Analysis of 27,360 Serology Tests, 2015-2020.

Objectives: Lyme borreliosis incidence is increasing in several areas; moreover, it has recently gained the public's attention. Apart from erythema migrans, Lyme disease diagnosis relies (among others) on serology test; however, the prevalence of positive enzyme-linked immunosorbent assay (ELISA) and western blot (WB) assay has been poorly studied in the general population. We aimed to approach the seroprevalence of infection by Borrelia species responsible for Lyme disease in the French Isere department using city laboratories data. Patients and Methods: We retrieved all serological tests for Borrelia species responsible for Lyme disease performed in the two main networks of city laboratories between 2015 and 2020. All patients with both ELISA and WB IgG were considered seropositive. Results: We analyzed 27,360 tests (ELISA/ELISA+WB). Mean age was 50.9 ± 20.3 years (ranges: 0-101), with 57.1% females. Overall, 11.7% had IgG detected by ELISA, and 4.7% had IgG detected by both ELISA and WB assay. Seropositive status was more frequent in males (7.0% vs. 2.9%, p < 0.001). Seropositivity rate increased with age after a first peak in childhood; men aged 61-70 years had the highest seropositivity rate (10.3%). In addition, seropositivity rate was higher in persons from a rural area. In multivariate analysis, older age, male gender and living in a rural area were independently associated with seropositivity. Seropositivity rate was stable on the 2017-2020 period. Conclusion: The seroprevalence of infection by Borrelia species responsible for Lyme disease is high in Isere; this probably reduces the predictive positive value for Lyme disease of ELISA and WB IgG, suggesting that this serological test should not be performed for nonspecific symptoms.

Single-domain antibodies reveal unique borrelicidal epitopes on the Lyme disease vaccine antigen, outer surface protein A (OspA).

Camelid-derived, single-domain antibodies (VHHs) have proven to be extremely powerful tools in defining the antigenic landscape of immunologically heterogeneous surface proteins. In this report, we generated a phage-displayed VHH library directed against the candidate Lyme disease vaccine antigen, outer surface protein A (OspA). Two alpacas were immunized with recombinant OspA serotype 1 from Borrelia burgdorferi sensu stricto strain B31, in combination with the canine vaccine RECOMBITEK Lyme containing lipidated OspA. The phage library was subjected to two rounds of affinity enrichment ("panning") against recombinant OspA, yielding 21 unique VHHs within two epitope bins, as determined through competition enzyme linked immunosorbent assays (ELISAs) with a panel of OspA-specific human monoclonal antibodies. Epitope refinement was conducted by hydrogen exchange-mass spectrometry. Six of the monovalent VHHs were expressed as human IgG1-Fc fusion proteins and shown to have functional properties associated with protective human monoclonal antibodies, including B. burgdorferi agglutination, outer membrane damage, and complement-dependent borreliacidal activity. The VHHs displayed unique reactivity profiles with the seven OspA serotypes associated with B. burgdorferi genospecies in the United States and Europe consistent with there being unique epitopes across OspA serotypes that should be considered when designing and evaluating multivalent Lyme disease vaccines.

Suppression of host humoral immunity by Borrelia burgdorferi varies over the course of infection.

Borrelia burgdorferi, the spirochetal agent of Lyme disease, utilizes a variety of strategies to evade and suppress the host immune response, which enables it to chronically persist in the host. The resulting immune response is characterized by unusually strong IgM production and a lack of long-term protective immunity. Previous studies in mice have shown that infection with B. burgdorferi also broadly suppresses host antibody responses against unrelated antigens. Here, we show that mice infected with B. burgdorferi and concomitantly immunized with recombinant severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein had an abrogated antibody response to the immunization. To further define how long this humoral immune suppression lasts, mice were immunized at 2, 4, and 6 weeks post-infection. Suppression of host antibody production against the SARS-CoV-2 spike protein peaked at 2 weeks post-infection but continued for all timepoints measured. Antibody responses against the SARS-CoV-2 spike protein were also assessed following antibiotic treatment to determine whether this immune suppression persists or resolves following clearance of B. burgdorferi. Host antibody production against the SARS-CoV-2 spike protein returned to baseline following antibiotic treatment; however, anti-SARS-CoV-2 IgM remained high, comparable to levels found in B. burgdorferi-infected but untreated mice. Thus, our data demonstrate restored IgG responses following antibiotic treatment but persistently elevated IgM levels, indicating lingering effects of B. burgdorferi infection on the immune system following treatment.

Lyme-Associated Pericarditis: A Case Report and Literature Review.

Lyme disease is caused by Borrelia burgdorferi (B. burgdorferi), which is a spirochete transmitted by ticks of the genus Ixodes. Complications related to the cardiovascular system usually occur in the early phase of infection, and the most common cardiovascular complication of Lyme disease is atrioventricular block, especially third-degree heart block. We report a case of a young Caucasian male patient who presented to the emergency department (ED) with complaints of chest pain and shortness of breath. Initial investigations, including chest X-ray, were negative. An EKG revealed ST elevation and PR depression with troponin elevation. The echocardiogram showed a normal ejection fraction with no pericardial effusion. Skin examination was positive for erythema migrans concerning Lyme. Initial Lyme testing was negative in the patient and it should be repeated after four to six weeks, according to the guidelines. This case report highlights the importance of keeping the differentials broad in these patients even if the initial testing is negative, especially since misdiagnosis or delayed diagnosis can cause cardiac complications.

By-degree Health and Economic Impacts of Lyme Disease, Eastern and Midwestern United States.

Lyme disease (LD) is the most common vector-borne disease in the United States (U.S.). This paper assesses how climate change may influence LD incidence in the eastern and upper Midwestern U.S. and the associated economic burden. We estimated future Ixodes scapularis habitat suitability and LD incidence with a by-degree approach using variables from an ensemble of multiple climate models. We then applied estimates for present-day and projected habitat suitability for I. scapularis, present-day presence of Borrelia burgdorferi, and projected climatological variables to model reported LD incidence at the county level among adults, children, and the total population. Finally, we applied an estimate of healthcare expenses to project economic impacts. We show an overall increase in LD cases with regional variation. We estimate an increase in incidence in New England and the upper Midwestern U.S. and a concurrent decrease in incidence in Virginia and North Carolina. At 3°C of national warming from the 1986-2015 baseline climate, we project approximately 55,000 LD cases, a 38-percent increase from present-day estimates. At 6°C of warming, our most extreme scenario, we project approximately 92,000 LD cases in the region, an increase of 145 percent relative to current levels. Annual LD-related healthcare expenses at 3°C of warming are estimated to be $236 million (2021 dollars), approximately 38 percent greater than present-day. These results may inform decision-makers tasked with addressing climate risks, the public, and healthcare professionals preparing for treatment and prevention of LD.

Parálisis facial, la importancia de realizar una buena historia clínica / Facial palsy, the importance of taking a good medical history

La parálisis facial plantea un diagnóstico diferencial amplio en Pediatría, sobre todo cuando se acompaña de sintomatología que orienta en contra de una parálisis de Bell, por lo que resulta imprescindible realizar una correcta anamnesis. La enfermedad de Lyme es una de las posibles causas de parálisis facial, habiendo sido poco descrita en niños en España. Presentamos el caso de un varón de 11 años con diagnóstico de parálisis facial asociada a infección por B. burgdorferi con evolución favorable tras tratamiento con doxiciclina. (AU)

Facial palsy poses a wide differential diagnosis in pediatrics, especially when it is accompanied by symptoms that make it doubtful whether Bell's palsy is present. It is essential to perform a correct anamnesis to rule out diagnoses that require early detection and treatment to improve the prognosis. Lyme disease (EL) is one of the possible causes of facial palsy, having been seldom described in children in Spain. We present the case of an 11-years-old male with diagnosis of facial palsy associated with B. burgdorferi infection with favorable evolution after treatment with doxycycline. (AU)

Atypical Lyme Disease Rash: A Case Report.

Lyme disease (LD), caused in the United States primarily by Borrelia burgdorferi sensu lato, is a tick-borne illness characterized by a spectrum of clinical manifestations depending on the stage of illness. Most clinicians are familiar with the classic bullseye appearance of the erythema migrans (EM) rash that occurs in the early stage of the disease. However, many providers may not be aware of alternate appearances for the rash. This paper reports the case of a 69-year-old female with LD, exhibiting an atypical rash with purplish discoloration that was devoid of an outer ring or central clearing. In geographic areas with a high incidence of LD, it is especially important for clinicians to recognize alternative LD presentations. Healthcare providers should maintain a high index of suspicion of LD in patients with tick bites, even without typical EM, to ensure early diagnosis and treatment. Education on diverse LD presentations is crucial for improving public health outcomes.

Hemophagocytic Lymphohistiocytosis (HLH) in Patients with Tick-Borne Illness: A Scoping Review of 98 Cases.

Hemophagocytic lymphohistiocytosis (HLH) secondary to tick-borne infections is a rare but potentially life-threatening syndrome. We performed a scoping review according to PRISMA guidelines to systematically analyze the existing literature on the topic. A total of 98 patients were included, with a mean age of 43.7 years, of which 64% were men. Most cases, 31%, were reported from the USA. Immunosuppression was present in 21.4%, with the most common cause being previous solid organ transplantation. Constitutional symptoms were the most common, observed in 83.7% of the patients, while fever was reported in 70.4% of cases. Sepsis was present in 27.6%. The most common laboratory abnormalities in this cohort were thrombocytopenia in 81.6% of patients, while anemia, leukopenia, and leukocytosis were observed in 75.5%, 55.1%, and 10.2%, respectively. Liver enzyme elevation was noted in 63.3% of cases. The H-score was analyzed in 64 patients, with the mean value being 209, and bone marrow analysis was performed in 61.2% of patients. Ehrlichia spp. was the main isolated agent associated with HLH in 45.9%, followed by Rickettsia spp. in 14.3% and Anaplasma phagocytophilum in 12.2%. Notably, no patient with Powassan virus infection or Lyme borreliosis developed HLH. The most common complications were acute kidney injury (AKI) in 35.7% of patients, shock with multiple organ dysfunction in 22.5%, encephalopathy/seizure in 20.4%, respiratory failure in 16.3%, and cardiac complications in 7.1% of patients. Treatment included antibiotic therapy alone in 43.9%, while 5.1% of patients were treated with immunosuppressants alone. Treatment with both antibiotics and immunosuppressants was used in 51% of patients. Appropriate empiric antibiotics were used in 62.2%. In 43.9% of cases of HLH due to tick-borne disease, patients received only antimicrobial therapy, and 88.4% of those recovered completely without the need for immunosuppressive therapy. The mortality rate in our review was 16.3%, and patients who received inappropriate or delayed empiric therapy had a worse outcome. Hence, we suggest empiric antibiotic treatment in patients who are suspected of having HLH due to tick-borne disease or in whom diagnostic uncertainty persists due to diagnostic delay in order to minimize mortality.

Through the Eyes of Uncertainty: Giant Cell Arteritis and Lyme Neuroborreliosis in a Story of Vision Loss.

Acute vision loss is a prevalent clinical manifestation associated with a broad spectrum of differential diagnoses, encompassing demyelinating diseases, neoplastic processes, autoimmune disorders, and infectious conditions. A rare but noteworthy infectious etiology contributing to acute vision loss is neurological Lyme disease (Lyme neuroborreliosis)-induced optic neuritis. Lyme disease, a vector-borne illness caused by the spirochete Borrelia burgdorferi, has the potential to affect multiple physiological systems and unfolds in three distinct stages. Another significant contributor to acute vision loss is giant cell arteritis, an autoimmune vasculitis that commonly affects large- and medium-sized vessels, including the temporal and ophthalmic arteries. This relatively common condition may manifest with symptoms, such as jaw claudication, headaches, and visual disturbances. The precise identification of the underlying cause of acute visual loss is of utmost importance for physicians, as it is instrumental in averting undesirable complications. An 80-year-old female presents to the emergency room with a sudden onset of blurry vision of the left eye, right-sided weakness, dysarthria, jaw pain, headache, and left facial droop. Following consultations with rheumatology and ophthalmology specialists, giant cell arteritis emerged as a primary consideration in the differential diagnosis for the observed vision loss. Subsequently, a temporal artery biopsy was conducted, definitively confirming the diagnosis of giant cell arteritis. Considering the patient's residence in an area endemic to Lyme disease, a Lyme immunoglobulin G (IgG) titer was ordered. The results returned positive, suggesting the presence of Lyme neuroborreliosis.