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Infectious Disorders Drug Targets 2020Recently, herbal medicine has received much attention in the literature. Several essential oils or plant extracts have been found to have anti-Acanthamoeba properties...
BACKGROUND
Recently, herbal medicine has received much attention in the literature. Several essential oils or plant extracts have been found to have anti-Acanthamoeba properties against trophozoites and cysts of Acanthamoeba spp.
OBJECTIVE
The aim of this systematic review is to introduce anti-Acanthamoeba properties of some essential oils or plant extracts; perhaps the results of this research will be used to prevent and treat infectious diseases.
METHODS
All published papers in English and Persian databases were systematically searched for some specific keywords to find articles that have influenced plant compounds on Acanthamoeba up to April 2018. Articles related to the subject were selected and studied.
RESULTS
A total of 51 articles including 136 experiments (128 in vitro and 8 in vivo) between 1999 and 2018, met our eligibility criteria. Totally, 110 species of plants belonging to 34 families, mainly Lamiaceae (15 plant species) and Asteraceae (13 plant species) were studied against trophozoites and cysts of Acanthamoba in in vitro and in vivo. Most of the plant's species were Citrus (6 species), Allium (5 species), Peucedanum, Piper, Lippia, and Olive (4 species). The most frequently used parts were leaves, aerial parts, flowers, bark, rhizomes, and seeds.
CONCLUSIONS
Recent studies have shown that many natural compounds have high anti-parasitic properties and low toxicity. Our research team hopes that the information provided in present systematic review can improve new experimental and clinical trials and herbal combination therapy. Further studies are needed to understand the molecular mechanisms in the anti-amoebic reactions of plant species and ocular toxicity of extracts in animal models.
Topics: Acanthamoeba; Amebiasis; Animals; Humans; Oils, Volatile; Phytotherapy; Plant Extracts; Plant Oils; Plants, Medicinal; Trophozoites
PubMed: 31322072
DOI: 10.2174/1871526519666190716095849 -
Annals of Parasitology 2018Acanthamoeba, an opportunistic protozoan parasite, is distributed in the environment globally, causes serious human infections, including a fatal encephalitis and... (Meta-Analysis)
Meta-Analysis
Acanthamoeba, an opportunistic protozoan parasite, is distributed in the environment globally, causes serious human infections, including a fatal encephalitis and keratitis. The purpose of this study was to evaluate the prevalence and genotyping of Acanthamoeba spp. from different water and soil sources in Iran. Six English language and four Persian language databases were searched to identify studies published from March 2005 to October 2016. Random effect model and Stats Direct statistical software was used for the meta-analysis. This review resulted in a total 34 articles meeting the including criteria. The overall prevalence rate of Acanthamoeba spp. among the 1850 water and soil samples in Iran with using random-effect model was estimated 42.7%. The genotyping results of the Acanthamoeba isolates showed that T4 (81.2%) was a predominant strain in Iran. In addition, other genotypes, T2, T3, T4, T5, T6, T11, T13, T15, mixed T3/T4 and mixed T2/T6, were obtained in the environmental samples of Iran. This study may be the first systematic review and meta-analysis of Acanthamoeba prevalence and genotyping in different environmental sources of Iran. Knowledge about wide distribution of Acanthamoeba T4 in the environmental sources may help physicians to manage the patients and susceptible persons in Iran.
Topics: Acanthamoeba; Acanthamoeba Keratitis; Genotype; Humans; Iran; Soil; Water
PubMed: 30710471
DOI: 10.17420/ap6404.163 -
Journal of Parasitic Diseases :... Dec 2017Free-living amoebae (FLA) are a group of protozoa with the capabilities of growth in the environment and invasion to the human body which have been isolated from... (Review)
Review
Free-living amoebae (FLA) are a group of protozoa with the capabilities of growth in the environment and invasion to the human body which have been isolated from different water sources. , , and are the most important FLA. These cause a variety of severe complications of eye and central nervous system. Despite the fact that various studies have demonstrated the prevalence of FLA in different parts of Iran, there is no comprehensive evaluation and conclusion regarding the pollution of various water sources in Iran. This review was carried out to achieve the prevalence pattern of FLA in water resources across Iran to design appropriate health strategies. For this purpose, 8 online databases in English and Persian and also graduate thesis and national parasitology congresses were studied. The key words such as "water resources", "water" and "Iran" were used to search articles between 1990 to 2017. From a total of 236 articles found, 38 reliable articles were included in the study. From the total number of investigated studies, the estimated prevalence was obtained as 36% among 2430 samples. Although prevalence has been considered as a priority, most kinds of free-living amoebae were found in all kinds of water resources. Due to the lack of free-living amoebae prevalence in more than a quarter of the Iranian provinces, more studies are recommended to achieve a better perspective to make comprehensive decisions to improve the hygiene of water resources.
PubMed: 29114120
DOI: 10.1007/s12639-017-0950-2 -
Asian Pacific Journal of Tropical... Sep 2017To verify phylogeography and genetic structure of Acanthamoeba populations among the Iranian clinical isolates and natural/artificial environments distributed in various... (Review)
Review
OBJECTIVE
To verify phylogeography and genetic structure of Acanthamoeba populations among the Iranian clinical isolates and natural/artificial environments distributed in various regions of the country.
METHODS
We searched electronic databases including Medline, PubMed, Science Direct, Scopus and Google Scholar from 2005 to 2016. To explore the genetic variability of Acanthamoeba sp, 205 sequences were retrieved from keratitis patients, immunosuppressed cases and environmental sources as of various geographies of Iran.
RESULTS
T4 genotype was the predominant strain in Iran, and the rare genotypes belonged to T2, T3, T5 (Acanthamoeba lenticulata), T6, T9, T11, T13 and T15 (Acanthamoeba jacobsi). A total of 47 unique haplotypes of T4 were identified. A parsimonious network of the sequence haplotypes demonstrated star-like feature containing haplogroups IR6 (34.1%) and IR7 (31.2%) as the most common haplotypes. In accordance with the analysis of molecular variance, the high value of haplotype diversity (0.612-0.848) of Acanthamoeba T4 represented genetic variability within populations. Neutrality indices of the 18S ribosomal RNA demonstrated negative values in all populations which represented a considerable divergence from neutrality. The majority of genetic diversity belonged to the infected contact lens and dust samples in immunodeficiency and ophthalmology wards, which indicated potential routes for exposure to a pathogenic Acanthamoeba sp. in at-risk individuals. A pairwise fixation index (F) was from low to high values (0.02433-0.41892). The statistically F points out that T4 is genetically differentiated between north-west, north-south and central-south metapopulations, but not differentiated between west-central, west-south, central-south, and north-central isolates.
CONCLUSIONS
An occurrence of IR6 and IR7 displays that possibly a gene flow of Acanthamoeba T4 occurred after the founder effect or bottleneck experience through ecological changes or host mobility. This is the first systematic review and meta-analysis providing new approaches into gene migration and transmission patterns of Acanthamoeba sp, and targeting at the high-risk individuals/sources among the various regions of Iran.
PubMed: 29080613
DOI: 10.1016/j.apjtm.2017.08.011 -
Infection Dec 2017Myopia is a prevalent condition among Asians. Orthokeratology lens has gained popularity as a method of myopia control. This systematic review is to summarize the... (Review)
Review
PURPOSE
Myopia is a prevalent condition among Asians. Orthokeratology lens has gained popularity as a method of myopia control. This systematic review is to summarize the clinical profile of infectious keratitis in association with orthokeratology lens wear.
METHODS
We searched in the PubMed and EMBASE for articles adopting the search strategy "(orthokeratology lens OR orthokeratology) AND (bacterial eye infection OR keratitis OR cornea ulcer OR microbial keratitis OR bacterial keratitis)", from the start date of the databases to August 23, 2016. Articles reporting infectious keratitis in orthokeratology lens users with data of individual cases were considered eligible for this systematic review. We recorded the outcome measures including method of diagnosis, etiological agents, duration and mode of treatment and treatment outcomes.
RESULTS
Our literature search yielded 172 papers. After removing duplicated and irrelevant reports, we included 29 articles for data analysis, involving 173 eyes. Among all reported cases, the mean age at presentation was 15.4 ± 6.2 years, with a female preponderance (male-to-female ratio 1:1.7). Positive microbiological cultures were reported in 69.4% of cases, with Pseudomonas aeruginosa and Acanthamoeba being the most common etiological agents. The mean duration of hospitalization was 7.7 ± 6.7 days. Mean LogMAR visual acuity at presentation was 1.17 ± 0.78, increased to 0.33 ± 0.41 at final visit (p < 0.001).
CONCLUSIONS
Despite early intervention and treatment, the majority of infections resulted in the formation of corneal scars and almost 10% of eyes needed surgical treatment. Timely awareness and treatment of keratitis should be emphasized to the users.
Topics: Corneal Ulcer; Eye Infections, Bacterial; Humans; Keratitis; Orthokeratologic Procedures
PubMed: 28534320
DOI: 10.1007/s15010-017-1023-2 -
Journal of Pediatric Ophthalmology and... May 2017Myopia is an important public health issue, and high myopia may lead to severe complications if left untreated. Orthokeratology lenses, worn overnight to reshape the... (Review)
Review
Myopia is an important public health issue, and high myopia may lead to severe complications if left untreated. Orthokeratology lenses, worn overnight to reshape the cornea, are one of many recent modalities used to slow down the progression of myopia in children. This treatment has been proven successful, as evidenced by decreased spherical refractive error and axial length relative to the control at interval follow-up ranging from 6 months to 5 years. In this systematic review, the authors collected published controlled studies that analyzed the efficacy of orthokeratology lens wear and calculated longitudinal relative changes in axial length, revealing a weighted average of -45.1% change in axial length at the 2-year follow-up. The exact mechanism by which orthokeratology lenses reduce myopia progression is unknown, but research shows that the corneal reshaping decreases peripheral hyperopic defocus and therefore increases peripheral myopic defocus to likely reduce stimuli for axial elongation and subsequent development of myopia. Use of orthokeratology lenses is generally safe, but cases of associated infectious keratitis may have a higher incidence of virulent organisms such as Pseudomonas, Acanthamoeba, and antibacterial-resistant strains of Staphylococcus, partially due to the required overnight use of these lenses. Orthokeratology is regarded as one of the most effective non-pharmacologic measures to slow progression of myopia in children and, with regular follow-up to ensure safety, continues to be one of the most effective treatments for myopia management around the world. [J Pediatr Ophthalmol Strabismus. 2017;54(3):142-148.].
Topics: Child; Humans; Myopia, Degenerative; Orthokeratologic Procedures; Refraction, Ocular; Treatment Outcome
PubMed: 28092397
DOI: 10.3928/01913913-20170106-01 -
Cornea Jan 2016To assess the efficacy of corneal collagen cross-linking (CXL) in the management of infectious keratitis. (Meta-Analysis)
Meta-Analysis Review
PURPOSE
To assess the efficacy of corneal collagen cross-linking (CXL) in the management of infectious keratitis.
METHODS
Comprehensive literature search was performed in MEDLINE/PubMed and Cochrane Central Register of Controlled Trials using combinations of the following search terms: "corneal collagen cross linking" or "photoactivated riboflavin" or "UVA light and riboflavin" and "infectious keratitis" or "corneal ulcer." Last search was on March 19, 2015. Extracted data from individual studies were summarized and summary proportions of eyes healed and complications for different subgroups were estimated.
RESULTS
Twenty-five studies were included (2 randomized controlled trials, 13 case series, and 10 case reports) with a total of 210 eyes of 209 patients, of which 175 eyes underwent CXL. Causative microorganisms were bacteria, fungi, acanthamoeba, and Herpes simplex virus in 96, 32, 11, and 2 cases, respectively. Coinfections were present in 13 and cause was inconclusive in 21 cases. Sixteen of 175 eyes received no additional antibiotics, whereas 159 underwent CXL as an adjunct to antimicrobial treatment. Proportion of eyes healed with CXL was 87.2% (95% confidence interval (CI), 81.9%, 91.8%). For bacterial keratitis, the proportion of eyes healed was 85.7% (95% CI, 78.5%, 91.7%), whereas 10/11 and 25/32 eyes with acanthamoeba and fungal keratitis, respectively, were healed (available data not sufficient to provide a valid proportion analysis). Treatment resulted in corneal melting and tectonic keratoplasty in both Herpes simplex virus cases.
CONCLUSIONS
CXL seems promising in the management of infectious keratitis, excluding viral infections. However, more randomized controlled trials are required to assess its efficacy.
Topics: Collagen; Cornea; Cross-Linking Reagents; Eye Infections, Bacterial; Humans; Keratitis
PubMed: 26509768
DOI: 10.1097/ICO.0000000000000644 -
The Cochrane Database of Systematic... Feb 2015Acanthamoeba are microscopic, free-living, single-celled organisms which can infect the eye and lead to Acanthamoeba keratitis (AK). AK can result in loss of vision in... (Review)
Review
BACKGROUND
Acanthamoeba are microscopic, free-living, single-celled organisms which can infect the eye and lead to Acanthamoeba keratitis (AK). AK can result in loss of vision in the infected eye or loss of eye itself; however, there are no formal guidelines or standards of care for the treatment of AK.
OBJECTIVES
To evaluate the relative effectiveness and safety of medical therapy for the treatment of AK.
SEARCH METHODS
We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (2015, Issue 1), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to January 2015), EMBASE (January 1980 to January 2015), PubMed (1948 to January 2015), Latin American and Caribbean Health Sciences Literature Database (LILACS) (1982 to January 2015), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrials.gov) and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic search for trials. We last searched the electronic databases on 9 January 2015.
SELECTION CRITERIA
We included randomized controlled trials (RCTs) of medical therapy for AK, regardless of the participants' age, sex, or etiology of disease. We included studies that compared either anti-amoeba therapy (drugs used alone or in combination with other medical therapies) with no anti-amoeba therapy or one anti-amoeba therapy with another anti-amoeba therapy.
DATA COLLECTION AND ANALYSIS
Two authors independently screened search results and full-text reports, assessed risk of bias, and abstracted data. We used standard methodological procedures as set forth by the Cochrane Collaboration.
MAIN RESULTS
We included one RCT (56 eyes of 55 participants) in this review. The study compared two types of topical biguanides for the treatment of AK: chlorhexidine 0.02% and polyhexamethylene biguanide (PHMB) 0.02%. All participants were contact lens wearers with a median age of 31 years. Treatment duration ranged from 51 to 145 days. The study, conducted in the UK, was well-designed and had low risk of bias overall.Outcome data were available for 51 (91%) of 56 eyes. Follow-up times for outcome measurements in the study were not reported. Resolution of infection, defined as control of ocular inflammation, relief of pain and photosensitivity, and recovery of vision, was 86% in the chlorhexidine group compared with 78% in the PHMB group (relative risk (RR) 1.10, 95% confidence intervals (CI) 0.84 to 1.42). In the chlorhexidine group, 20 of 28 eyes (71%) had better visual acuity compared with 13 of 23 eyes (57%) in the PHMB group at final follow-up (RR 1.26, 95% CI 0.82 to 1.94). Five participants required therapeutic keratoplasty: 2 in the chlorhexidine group compared with 3 in the PHMB group (RR 0.55, 95% CI 0.10 to 3.00). No serious adverse event related to drug toxicity was observed in the study.
AUTHORS' CONCLUSIONS
There is insufficient evidence to evaluate the relative effectiveness and safety of medical therapy for the treatment of AK. Results from the one included study yielded no difference with respect to outcomes reported between chlorhexidine and PHMB. However, the sample size was inadequate to detect clinically meaningful differences between the two groups as indicated by the wide confidence intervals of effect estimates.
Topics: Acanthamoeba Keratitis; Anti-Infective Agents, Local; Biguanides; Chlorhexidine; Humans; Randomized Controlled Trials as Topic
PubMed: 25710134
DOI: 10.1002/14651858.CD010792.pub2 -
Seminars in Ophthalmology 2016To describe the infectious complications and the group of pathogens involved in the infection following corneal crosslinking, the visual outcome, and the treatment... (Review)
Review
AIM
To describe the infectious complications and the group of pathogens involved in the infection following corneal crosslinking, the visual outcome, and the treatment proposed.
METHODS
A Medline (National Library of Medicine, Bethesda, MD, USA) search from October 2000 to October 2013 was performed to identify all articles describing infectious keratitis following corneal crosslinking treatment. Nineteen articles were selected. Ten articles reported infectious complications of corneal crosslinking treatment were included. Nine articles were excluded, because seven described sterile keratitis, one article was in German, and one reported general complication without describing the infection complication.
RESULTS
A total number of infections reported included 10 eyes. The infectious keratitis was associated with bacteria in five eyes (50%): gram-positive bacteria in three eyes (30%) (staphylococcus epidermidis, S. aureus and streptococcus salivarius plus S. oralis, respectively) and gram-negative bacteria in two eyes (20%) (E. coli; P. aeruginosa); there was herpes virus in two eyes, fungus in two eyes (Fusarium and Microsporidia) (20%), and Acanthamoeba in one eye (10%).
CONCLUSIONS
Only 10 cases of infectious keratitis following corneal crosslinking are published. The most virulent pathogens were Pseudomonas aeruginosa and Acanthamoeba. Less virulent organisms were Escherichia coli and S. epidermidis. Two cases of herpes keratitis were described, suggesting the possibility of systemic antiviral prophylaxis before corneal crosslinking treatment. The most common risk factor of infections identified was postoperative incorrect patient behavior.
Topics: Adult; Collagen; Corneal Stroma; Cross-Linking Reagents; Eye Infections; Humans; Keratitis; Photosensitizing Agents; Postoperative Complications; Riboflavin; Risk Factors; Ultraviolet Rays; Visual Acuity; Young Adult
PubMed: 25392046
DOI: 10.3109/08820538.2014.962176