In vitro evaluation of antibacterial activity of phytochemicals and micronutrients against Borrelia burgdorferi and Borrelia garinii

Aims

Little is known about the effects of phytochemicals against Borrelia sp. causing Lyme disease. Current therapeutic approach to this disease is limited to antibiotics. This study examined the anti‐borreliae efficacy of several plant‐derived compounds and micronutrients.

Methods and Results

We tested the efficacy of 15 phytochemicals and micronutrients against three morphological forms of Borrelia burgdoferi and Borrelia garinii: spirochetes, latent rounded forms and biofilm. The results showed that the most potent substances against the spirochete and rounded forms of B. burgdorferi and B. garinii were cis‐2‐decenoic acid, baicalein, monolaurin and kelp (iodine); whereas, only baicalein and monolaurin revealed significant activity against the biofilm. Moreover, cis‐2‐decenoic acid, baicalein and monolaurin did not cause statistically significant cytotoxicity to human HepG2 cells up to 125 μg ml⁻¹ and kelp up to 20 μg ml⁻¹.

Conclusions

The most effective antimicrobial compounds against all morphological forms of the two tested Borrelia sp. were baicalein and monolaurin. This might indicate that the presence of fatty acid and phenyl groups is important for comprehensive antibacterial activity.

Significance and Impact of the Study

This study reveals the potential of phytochemicals as an important tool in the fight against the species of Borrelia causing Lyme disease.

Chronic Lyme disease

Chronic Lyme disease is a poorly defined diagnosis that is usually given to patients with prolonged, unexplained symptoms or with alternative medical diagnoses. Data do not support the proposition that chronic, treatment-refractory infection with Borrelia burgdorferi is responsible for the many conditions that get labeled as chronic Lyme disease. Prolonged symptoms after successful treatment of Lyme disease are uncommon, but in rare cases may be severe. Prolonged courses of antibiotics neither prevent nor ameliorate these symptoms and are associated with considerable harm.

Lyme disease/borreliosis as a systemic disease

Lyme disease/borreliosis (LD) is a well-known arthropod-transmitted entity in the northern hemisphere. The incidence of LD is reportedly rising throughout the world, although better diagnostic facilities may be contributory. The disease distribution is expanding in Europe, with its presence being now documented at higher altitudes and latitudes. Borrelia burgdorferi sensu lato is the most important genospecies leading to LD, although newer ones continue to be discovered. The variations in clinical spectrum with genospecies involved are an interesting feature. The alteration in gene expression while the organism cycles between two very different hosts is intriguing and has been described. The disease presents in three stages-namely, the early localized, early disseminated, and late stage. Erythema chronicum migrans is the pathognomic early lesion, and its diagnosis is purely clinical; however, laboratory diagnosis is essential for later manifestations. Two-tier serologic testing using an enzyme-linked immunosorbent assay (ELISA) as the first tier and immunoglobulin M (IgM) and IgG immunoblot as the second, if ELISA is positive or equivocal, is the mainstay of diagnosis. Doxycycline is the cornerstone of treatment, whereas parenteral therapy, mainly with ceftriaxone, is indicated in a few specific scenarios.

Lyme Borreliosis: An Update for Canadian Dermatologists

Background:

Lyme borreliosis is a multisystemic tick-borne spirochetosis, which may result in dermatologic, musculoskeletal, cardiovascular, and neurologic manifestations.

Objective:

Patients with suspected acute Lyme borreliosis infection may be referred for urgent dermatologic review. Canadian dermatologists should be aware of the latest information regarding the diagnosis and management of Lyme borreliosis.

Methods:

This review is based on a PubMed database search combining the word “Lyme” with variations of the word “Canada.” Data sources included articles from the fields of ecology, epidemiology, laboratory diagnostics, and clinical management.

Conclusion:

In this review, the ecological basis of spirochete transmission by tick vectors is described. The latest available Canadian epidemiologic data are summarized. North American clinical manifestations of Lyme borreliosis are contrasted with European presentations. The Canadian Public Health Laboratory Network's diagnostic guidelines are summarized. Finally, treatment recommendations are outlined.

Diagnosis and treatment of tick infestation and tick-borne diseases with cutaneous manifestations

Hard and soft ticks may be associated directly or indirectly with a number of dermatoses, both infectious and inflammatory in origin. Morbidity may occur as a result of tick bites, tick toxicosis, and even infestation. These arthropod vectors may transmit life-threatening protozoan, bacterial, rickettsial, and viral diseases with systemic and cutaneous findings. Additionally, ticks may transmit more than one pathogen with subsequent human coinfection. This article reviews the presentation of tick-borne illnesses and the medical management of these diseases. Among others, diseases such as ehrlichiosis, anaplasmosis, babesiosis, tularemia, borrelioses, tick-borne encephalitides, rickettsial spotted fevers, and tick typhus are discussed in this article. The recognition of skin manifestations associated with these diseases is paramount to early diagnosis and treatment initiation.