Annular infectious dermatoses.

Annular configuration is conspicuous in the clinical manifestation of many skin diseases and can be helpful for the diagnosis and differential diagnosis. Variations may include arciform, ring-form, annular, circinate, serpiginous, gyrated, polycyclic, targeted or figurate forms, in different colors, sizes, and numbers, with various textures and surfaces. In infectious dermatoses, the annular reactions can be specific or nonspecific, while the underlying mechanisms remain largely unknown. In the specific reactions caused by direct invasion of the pathogens, the contest between the centrifugal outspread of the infectious agents and the centripetal impedance of the host immune response is supposed to determine the final conformation. Examples include erythema infectiosum, orf, erythema multiforme, and pityriasis rosea of viral origin. Bacterial infections that may display annular lesions include erythrasma, erythema (chronicum) migrans of Lyme borreliosis, secondary syphilis, cutaneous tuberculosis, and leprosy. Superficial mycosis, such as dermatophytosis, candida intertrigo, tinea imbricata, and subcutaneous mycosis, such as chromoblastomycosis, and algae infection protothecosis, are characterized by annular progression of the skin lesions. The creeping serpiginous extension is an alarming sign for the diagnosis of cutaneous larva migrans. A better understanding of the virulence and pathogenicity of the pathogens and the way and type of immune response will help to clarify the pathogenesis.

Effect of dapsone alone and in combination with intracellular antibiotics against the biofilm form of B. burgdorferi.

OBJECTIVE: Lyme disease is a tick-borne, multisystemic disease caused by Borrelia burgdorferi. Standard treatments for early Lyme disease include short courses of oral antibiotics but relapses often occur after discontinuation of treatment. Several studies have suggested that ongoing symptoms may be due to a highly antibiotic resistant form of B. burgdorferi called biofilms. Our recent clinical study reported the successful use of an intracellular mycobacterium persister drug used in treating leprosy, diaminodiphenyl sulfone (dapsone), in combination therapy for the treatment of Lyme disease. In this in vitro study, we evaluated the effectiveness of dapsone individually and in combination with cefuroxime and/or other antibiotics with intracellular activity including doxycycline, rifampin, and azithromycin against Borrelia biofilm forms utilizing crystal violet biofilm mass, and dimethyl methylene blue glycosaminoglycan assays combined with Live/Dead fluorescent microscopy analyses. RESULTS: Dapsone, alone or in various combinations with doxycycline, rifampin and azithromycin produced a significant reduction in the mass and protective glycosaminoglycan layer and overall viability of B. burgdorferi biofilm forms. This in vitro study strongly suggests that dapsone combination therapy could represent a novel and effective treatment option against the biofilm form of B. burgdorferi.

Metamorphoses of Lyme disease spirochetes: phenomenon of Borrelia persisters.

The survival of spirochetes from the Borrelia burgdorferi (sensu lato) complex in a hostile environment is achieved by the regulation of differential gene expression in response to changes in temperature, salts, nutrient content, acidity fluctuation, multiple host or vector dependent factors, and leads to the formation of dormant subpopulations of cells. From the other side, alterations in the level of gene expression in response to antibiotic pressure leads to the establishment of a persisters subpopulation. Both subpopulations represent the cells in different physiological states. "Dormancy" and "persistence" do share some similarities, e.g. both represent cells with low metabolic activity that can exist for extended periods without replication, both constitute populations with different gene expression profiles and both differ significantly from replicating forms of spirochetes. Persisters are elusive, present in low numbers, morphologically heterogeneous, multi-drug-tolerant cells that can change with the environment. The definition of "persisters" substituted the originally-used term "survivors", referring to the small bacterial population of Staphylococcus that survived killing by penicillin. The phenomenon of persisters is present in almost all bacterial species; however, the reasons why Borrelia persisters form are poorly understood. Persisters can adopt varying sizes and shapes, changing from well-known forms to altered morphologies. They are capable of forming round bodies, L-form bacteria, microcolonies or biofilms-like aggregates, which remarkably change the response of Borrelia to hostile environments. Persisters remain viable despite aggressive antibiotic challenge and are able to reversibly convert into motile forms in a favorable growth environment. Persisters are present in significant numbers in biofilms, which has led to the explanation of biofilm tolerance to antibiotics. Considering that biofilms are associated with numerous chronic diseases through their resilient presence in the human body, it is not surprising that interest in persisting cells has consequently accelerated. Certain diseases caused by pathogenic bacteria (e.g. tuberculosis, syphilis or leprosy) are commonly chronic in nature and often recur despite antibiotic treatment. Three decades of basic and clinical research have not yet provided a definite answer to the question: is there a connection between persisting spirochetes and recurrence of Lyme disease in patients?

Lyme disease in Haryana, India.

Lyme disease is a multiorgan animal-borne disease caused by the spirochete Borrelia burgdorferi. This case series highlights its presence in Haryana, a nonendemic zone. The first case was a 27-year-old housewife who presented with an annular erythematous patch with a central papule following an insect bite on the left upper arm. The second case was a 32-year-old farmer who gave a history of insect bite on the right arm followed by the development of an erythematous patch with a central blister. The third case, a 17-year-old boy presented with a history of tick bite over right thigh and a typical bull's eye lesion with central ulceration. These cases were managed with oral doxycycline 100 mg twice daily for 14 days. The fourth case was a 7-year-old boy with typical erythema migrans on the right check and neck while the fifth case, a 30-year-old housewife, presented with an erythematous patch with a central papule on the right buttock. These patients were treated with oral amoxycillin 25 mg/kg, thrice daily for 14 days. All patients showed IgM antibodies to B. burgdorferi. Treatment led to clearance of lesions in all the patients. Lyme borreliosis was diagnosed in these patients based on the history of established exposure to tick bites, presence of classic signs and symptoms, serology and the response to treatment.

Polymerase chain reaction-based molecular diagnosis of cutaneous infections in dermatopathology.

Conventional methods, including microscopy, culture, and serologic studies, are a mainstay in the diagnosis of cutaneous infection. However, owing to limitations associated with these techniques, such as low sensitivity for standard microscopy and in the case of culture delay in diagnosis, polymerase chain-reaction based molecular techniques have taken on an expanding role in the diagnosis of infectious processes in dermatopathology. In particular, these assays are a useful adjunct in the diagnosis of cutaneous tuberculosis, atypical mycobacterial infection, leprosy, Lyme disease, syphilis, rickettsioses, leishmaniasis, and some fungal and viral infections. Already in the case of tuberculosis and atypical mycobacterial infection, standardized polymerase chain-reaction assays are commonly used for diagnostic purposes. With time, additional molecular-based techniques will decrease in cost and gain increased standardization, thus delivering rapid diagnostic confirmation for many difficult-to-diagnose cutaneous infections from standard formalin-fixed paraffin-embedded tissue specimens.

Infectious neuropathy.

PURPOSE OF REVIEW: Infectious neuropathy affects a large number of people worldwide. There is evidence of direct involvement of nerves by the infective agent, from the immune reaction of the patient or secondary to the toxicity of the drugs used during treatment. This group of neuropathies is often treatable or preventable. RECENT FINDINGS: There is a complex clinical picture of the neuropathy of leprosy, different pathological features and immunological mechanisms. If the skin is unaffected in leprosy it is not always easy to demonstrate that the neuropathy is due to leprosy. Peripheral neuropathy in patients with chronic infection with hepatitis C virus may be due to the virus, the development of vasculitis or direct neurotoxic effects of the treatment. Peripheral neuropathy has become the chief neurological syndrome in individuals infected with HIV-1. The antiretroviral therapies themselves can cause peripheral neuropathies clinically indistinguishable from those caused by the virus. The occurrence of chronic polyneuropathy as a late manifestation in Lyme disease is extremely rare and is not well understood. SUMMARY: Although infectious neuropathies are very frequent, mainly in developing countries, further studies are needed to elucidate their mechanisms of action, focusing on preventive interventions.

Infectious neuropathies.

Peripheral neuropathies can result from several infective agents, ranging from viruses, especially retroviruses, to parasites and bacilli. Leprosy, which often is considered a disorder of the past, still is common in dome geographic areas, especially in Africa, South America, and Asia. An increasing number of cases of neuropathies occurs in patients who have HIV or Lyme disease. The important point is that all these neuropathies are treatable and often preventable.

[Minocycline]. / Minocycline.

Minocycline belongs to the second generation class of cyclines. It was synthesized in 1967 and marketed in 1972. Minocycline has an antiinfectious activity with a spectrum similar to that of other cyclines, notably against Chlamydias, Treonema and Proprionibacterium acenes. The antiinflammatory activity is associated with this antiinfectious action is greater than that of first generation cyclines with specifically a modulator effect on epidermal cytokines. The pharmokinetics of minocycline is characterized by an excellent absorption, a long half-life and an important lipophilic property inducing good tissue distribution. Clinical trials of minocycline have mainly been performed in sexually transmissible diseases and in acne, a field where randomized studies are the most frequent. These trials show that the effect of minocycline is not stronger than first generation cyclines or doxycycline, but that the action is quicker than that of tetracycline at the dose of 500 mg a day. Minocycline is also efficient in nocardiasis, mycobacteriosis, leprosy, Lyme disease, pyoderma gangrenosum, autoimmune bullous dermatitis, Carteaud disease, and prurigo. However, the effect of minocycline in these different conditions has always been evaluated in open trials with a small number of patients. The usual side effects of cyclines, i.e. digestive problems, fungal infections, are less frequent than with first generation cyclines. No photosensitivity has been demonstrated although pigmentations have been described. Dizziness is a specific side effect of minocycline. Furthermore, rare but severe side effects have been reported, including hypersensitivity syndrome, autoimmune hepatitis, and lupus. Regular indications for minocycline in dermatology are acne and three sexually transmissible diseases (mycoplasm, chlamydia, treponema). Proposed dosage is 100 mg per day in sexually transmissible disease with a reduction to 50 mg per day after 15 days in acne.

[Infectious neuropathies]. / Neuropathies infectieuses.

Infective neuropathies constitute a leading cause of neuropathies in the world. The number of patients with nerve lesions related to leprosy remains high despite decreasing number of new cases requiring multidrug regimens. Peripheral neuropathies associated with HIV infection may be found in up to 50% of patients. Neuropathies may be related to the inflammatory reaction against viral antigens, immunodepression, opportunistic infections, and iatrogenic complications of anti-viral drugs. Hepatitis C virus infection has been found in cryoglobulinemic neuropathies. This virus should be screened for exploration of all neuropathies. Rare causes of neuropathy, such as poliomyelitis and diphtheria, and treatable neuropathies such as Lyme disease, should not be forgotten.

Bilateral facial nerve palsy: four case reports.

Bilateral facial nerve palsy is relatively uncommon and may occur in association with a variety of neurological, infectious, neoplastic or degenerative disorders. Presentation is made of 4 cases of bilateral facial diplegia due to a refractory anemia with excess of blasts, a Lyme disease and a tuberculoid leprosy. In one of these patients the cause of bilateral seventh-nerve palsy was unknown (Bell's palsy). Facial palsy returned to normal after treatment with steroids in 3 patients. The patient with myelodysplastic syndrome did not show any improvement and died 6 months after diagnosis.