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1.
BMC Ophthalmol ; 24(1): 164, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38622551

RESUMO

PURPOSE: To analyze the clinicopathological characteristics and surgical outcomes of patients with Wolfring gland ductal cysts (WGDCs). METHODS: A retrospective, consecutive, interventional comparative case series was performed over a period of 7 years. Data on demographic and clinical characteristics, pathological findings and outcomes of surgically excised cysts were collected. A comparison between the transconjunctival and transcutaneous approaches was also assessed. RESULTS: Forty-eight patients (48 eyelids) were included in the final analysis. The most common presenting symptom was painless eyelid swelling (81.3%). The median symptom duration was 11.5 months (IQR, 18.25). The upper eyelid was involved in 31 (64.6%) patients, 29/31 of whom had cysts in a medial or centromedial location. Forty-five (93.8%) cysts were bluish gray and transilluminable with clear contents on lid eversion and a median largest dimension of 22 mm (IQR, 8). A transverse conjunctival fibrotic band was observed along the proximal tarsal border in the cyst area in all patients. Signs of chronic trachoma were noted in 38 (79.2%) patients. Preoperative significant ptosis was present in 28/31 (90.3%) of the upper eyelid cysts. Thirty cysts (62.5%) were excised through the skin, and 18 cysts (37.5%) were excised transconjunctivally. Intraoperative cyst rupture, the need for conjunctival grafting and postoperative residual upper lid ptosis were significantly greater in the transconjunctival group (p = 0.009, p < 0.001, and p = 0.016, respectively). CONCLUSION: The present study highlights the clinicopathological characteristics of a relatively large series of surgically excised WGDCs. Transcutaneous excision of WGDCs has proven to be an effective treatment with fewer adverse sequelae than the transconjunctival approach.


Assuntos
Blefaroptose , Cistos , Humanos , Estudos Retrospectivos , Pálpebras/cirurgia , Pálpebras/patologia , Resultado do Tratamento , Cistos/cirurgia , Cistos/patologia
2.
Orbit ; : 1-6, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38743616

RESUMO

PURPOSE: To describe a novel transconjunctival technique for excision of well-defined masses of the orbital lobe of the lacrimal gland. METHODS: Case series of three patients undergoing excision of a well-defined mass of the orbital lobe of lacrimal gland using a swinging upper eyelid flap. This technique entails a supratarsal conjunctival incision combined with lateral canthotomy and superior cantholysis. RESULTS: Complete removal of the mass without visible scars was achieved in all cases. There were no complications related to this approach. CONCLUSION: The swinging upper eyelid approach produces a wide exposure of the superolateral orbit. It allows safe removal of large lacrimal gland masses without the need for bone removal, while affording acceptable cosmesis.

3.
Orbit ; : 1-6, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38861504

RESUMO

PURPOSE: Periocular lesions in pediatric patients usually require general anesthesia for surgical intervention. The US Food and Drug Administration (FDA) warns against multiple exposures to anesthesia in children younger than 3 years due to the increased risk of learning disabilities in this population. This study aimed to evaluate risk factors associated with chalazion recurrence after surgery. METHODS: A retrospective chart review over a five-year period identified 649 patients at our institution undergoing surgical intervention for chalazion. The primary outcomes examined were as follows: (1) return to the operating room for additional surgical intervention and (2) recurrence of chalazion during convalescence from surgery and follow-up. RESULTS: Fewer than one-third of patients suffered a recurrence after surgery. Multivariate logistic regression found younger age (p = 0.01), female sex (p = 0.01), and a greater number of chalazia drained (p < 0.001) were significantly correlated with recurrence of chalazia after surgery. CONCLUSIONS: Patients presenting at a younger age and with a greater number of chalazion were statistically more likely to have a recurrence of chalazion after surgery. Given recurrence is more likely in younger children, reconciling this with the risk-benefit ratio with regard to FDA guidelines on anesthesia in children under three years is a critical consideration for ophthalmologists.

4.
Proc Biol Sci ; 290(2003): 20231119, 2023 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-37491967

RESUMO

Bacterial infections are often polymicrobial, leading to intricate pathogen-pathogen and pathogen-host interactions. There is increasing interest in studying the molecular basis of pathogen interactions and how such mechanisms impact host morbidity. However, much less is known about the ecological dynamics between pathogens and how they affect virulence and host survival. Here we address these open issues by co-infecting larvae of the insect model host Galleria mellonella with one, two, three or four bacterial species, all of which are opportunistic human pathogens. We found that host mortality was always determined by the most virulent species regardless of the number of species and pathogen combinations injected. In certain combinations, the more virulent pathogen simply outgrew the less virulent pathogen. In other combinations, we found evidence for negative interactions between pathogens inside the host, whereby the more virulent pathogen typically won a competition. Taken together, our findings reveal positive associations between a pathogen's growth inside the host, its competitiveness towards other pathogens and its virulence. Beyond being generalizable across species combinations, our findings predict that treatments against polymicrobial infections should first target the most virulent species to reduce host morbidity, a prediction we validated experimentally.


Assuntos
Infecções Bacterianas , Mariposas , Animais , Humanos , Virulência , Mariposas/microbiologia , Larva/microbiologia , Interações Hospedeiro-Patógeno
5.
Ophthalmic Plast Reconstr Surg ; 39(6): 525-532, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37010053

RESUMO

PURPOSE: The oculofacial plastic surgeon will more frequently encounter challenges related to overweight and obese patients as the incidence rises. There is a paucity of data in the oculofacial plastic surgical literature regarding this topic. The goal of this review is to detail the role obesity plays in the perioperative course and the considerations for a surgeon treating this patient population. METHODS: The authors conducted a computerized search using PubMed, Embase, and Google Scholar. The search terms used were "(obesity OR overweight) AND surgery," "(obesity OR overweight) AND oculoplastic," "(obesity OR overweight) AND oculofacial," "(obesity OR overweight) AND 'facial plastic surgery', " "(obesity OR overweight) AND 'bariatric surgery', " "(obesity OR overweight) AND (pre-operative OR post-operative OR intraoperative," " (obesity OR overweight) AND complications," "(obesity OR overweight) AND (facial plastic surgery) AND complications)," "(obesity OR overweight) AND eyelid," "(obesity OR overweight) AND (nasolacrimal OR 'nasolacrimal duct')," "(obesity OR overweight) AND IIH," "(obesity OR overweight) AND exophthalmos." RESULTS: A total of 127 articles, published from 1952 to 2022 in the English language or with English translations were included. Articles published earlier than 2000 were cited for foundational knowledge. References cited in the identified articles were also used to gather further data for the review. CONCLUSIONS: Overweight and obese patients pose specific challenges that the oculofacial plastic surgeon should be aware of to better optimize patient outcomes. Multiple comorbidities, poor wound healing, and nutritional deficits all contribute to the complications experienced in this patient population. Further investigation on overweight and obese patients is needed.


Assuntos
Procedimentos de Cirurgia Plástica , Cirurgia Plástica , Humanos , Sobrepeso/complicações , Sobrepeso/cirurgia , Obesidade/complicações , Obesidade/cirurgia , Comorbidade
6.
Orbit ; : 1-18, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37728602

RESUMO

Traditionally, for patients who are poor candidates for surgery and/or radiotherapy, palliative chemotherapy is often offered but with significant toxic side effects. However, recent advancements in our understanding of tumor biology and molecular genetics have brought new understanding to the molecular pathways of certain tumors and cancers. This has ushered in a new era of precision medicine specific to a tumor or cancer treatment pathway (targeted therapy) or directed to host-tumor responses (immunotherapy). This article will focus on recent updates in the application of available targeted and immunotherapy for managing orbital and periorbital tumors and tumor-like conditions, which include cutaneous basal cell carcinoma, cutaneous squamous cell carcinoma, cutaneous melanoma, Merkel cell carcinoma, sebaceous gland carcinoma, solitary fibrous tumor, dermatofibrosarcoma protuberans, orbital meningioma, neurofibromatosis, Langerhans cell histiocytosis, ocular adnexal lymphoma, orbital lymphatic malformation, and adenoid cystic carcinoma.

7.
Orbit ; 41(2): 162-169, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34486478

RESUMO

The congenital absence of tear production or alacrima is a distinctively unusual clinical sign that harbors a wide variety of etiologies. While alacrima can be only isolated to the lacrimal system, it is more often associated with progressive multisystem involvement from underlying genetic disorders. Recognizing the subtle ocular signs in these diseases will promote a timely diagnosis and management before potential life-threatening consequences occur. Hence, the current article will review the ophthalmological findings, systemic manifestations, genetic associations, and differential diagnosis of congenital alacrima.


Assuntos
Síndromes do Olho Seco , Oftalmopatias Hereditárias , Doenças do Aparelho Lacrimal , Aparelho Lacrimal , Síndromes do Olho Seco/etiologia , Oftalmopatias Hereditárias/complicações , Oftalmopatias Hereditárias/diagnóstico , Humanos , Aparelho Lacrimal/anormalidades , Doenças do Aparelho Lacrimal/complicações , Doenças do Aparelho Lacrimal/diagnóstico , Doenças do Aparelho Lacrimal/genética , Lágrimas
8.
Orbit ; 41(2): 141-149, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34044737

RESUMO

The permeation of social media into life almost goes without bounds and medicine is no exception. While social media holds great potential for physicians and medicine, it also comes with concurrent spread of disinformation. This increases the importance of evidence-based information from qualified physicians on social media.Although the definition of social media is broad, in general, it refers to the use of web-based platforms to connect one human to another. In oculoplastic surgery, these relationships can be physician to physician, physician to patient, patient to patient, and vendor to physician. These relationships mostly involve education, social support, and advertising, but can also include research and government advocacy. The purpose of this review is to evaluate the current utilization of social media in oculoplastic surgery and relevant subspecialties.


Assuntos
Oftalmologia , Procedimentos de Cirurgia Plástica , Mídias Sociais , Humanos
9.
Orbit ; 41(5): 633-636, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33874837

RESUMO

A 6-month-old female presented with bilateral periorbital edema for 7 days. Laboratory testing was significant for active SARS-CoV-2 infection. Neuroimaging demonstrated soft tissue changes within the bilateral orbits and enlargement of the bilateral lacrimal glands. Although the patient initially improved with corticosteroid treatment, she later returned with recurrent left periorbital and eyelid edema. Orbital biopsy was performed and demonstrated findings in the lacrimal gland and the adjacent fibroconnective tissues that are similar to those of prior lung specimens seen in SARS-CoV-2 patients. Final diagnosis was bilateral orbital inflammation with features presumed secondary to SARS-CoV-2 infection. To the best of our knowledge, this is one of the first reports to document bilateral orbital inflammation as a sign of SARS-CoV-2 infection in the pediatric population with the associated pathological findings.


Assuntos
COVID-19 , Aparelho Lacrimal , Criança , Edema , Feminino , Humanos , Lactente , Inflamação , SARS-CoV-2
10.
Orbit ; 41(4): 480-484, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33557696

RESUMO

Optic nerve infiltration is a rare but known complication of the central nervous system (CNS)-involving lymphoma and leukemic disorders. The diagnosis is often presumed and patients are empirically treated with systemic therapy and/or local radiation. Optic nerve biopsy is usually avoided due to the risk of permanent vision loss secondary to the procedure. We present a case of biopsy-proven leukemic optic neuropathy without optic nerve sheath or cerebrospinal fluid (CSF) involvement in a patient previously in remission from T-cell prolymphocytic leukemia (T-PLL). To our knowledge, this is the first documented case of T-PLL with biopsy-proven optic nerve invasion without CSF involvement and suggests possible perineural invasion or a sanctuary site from chemotherapy. We suggest that for patients with poor vision and suspected leukemic infiltration without other evidence of CNS involvement, both optic nerve and optic sheath biopsy should be performed for diagnosis and treatment.


Assuntos
Doenças do Nervo Óptico , Nervo Óptico , Biópsia , Olho , Humanos , Infiltração Leucêmica/patologia , Nervo Óptico/diagnóstico por imagem , Doenças do Nervo Óptico/diagnóstico
11.
Ophthalmic Plast Reconstr Surg ; 37(3S): S128-S130, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33009324

RESUMO

Oncocytoma is a rare benign neoplasm with few cases reported to involve the orbit. When affecting the orbit, oncocytomas have very slow growth and often evade early diagnosis. The diagnostic evaluation of these orbital tumors is not fully understood. The authors present a case of a benign oncocytoma arising in the lacrimal gland associated with significant vascularity and intraoperative bleeding. The authors provide immunohistochemical analysis of this rare orbital tumor and insights in surgical planning.


Assuntos
Adenoma Oxífilo , Doenças do Aparelho Lacrimal , Aparelho Lacrimal , Neoplasias Orbitárias , Adenoma Oxífilo/diagnóstico por imagem , Adenoma Oxífilo/cirurgia , Diagnóstico por Imagem , Humanos , Aparelho Lacrimal/diagnóstico por imagem , Doenças do Aparelho Lacrimal/diagnóstico , Doenças do Aparelho Lacrimal/cirurgia
12.
Ophthalmic Plast Reconstr Surg ; 37(3S): S149-S151, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32976334

RESUMO

Hidradenoma is a rare benign neoplasm, with few cases reported to involve the eyelid. When affecting the eyelid, hidradenomas may mimic other benign or malignant lesions. Rarely, a benign hidradenoma may transform into a malignant hidradenoma and metastasize. The authors present a case of a benign hidradenoma arising from the eyelid, presenting with rapid growth, ulceration, and bleeding, suggestive of a malignant lesion.


Assuntos
Acrospiroma , Adenocarcinoma de Células Claras , Adenoma de Glândula Sudorípara , Neoplasias das Glândulas Sudoríparas , Acrospiroma/diagnóstico , Acrospiroma/cirurgia , Pálpebras/cirurgia , Humanos , Neoplasias das Glândulas Sudoríparas/diagnóstico , Neoplasias das Glândulas Sudoríparas/cirurgia
13.
Ophthalmic Plast Reconstr Surg ; 37(1): 33-37, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32282642

RESUMO

PURPOSE: To compare the degree of ptosis and the risk of ptosis repair failure among patients with and without a history of topical corticosteroid use. METHODS: Retrospective, case-controlled study examining topical corticosteroid use among adults with ptosis who underwent external levator advancement/resection (ELR) or Müller muscle conjunctival resection with at least 3 months postoperative follow-up. Comparative statistical analyses of surgical outcomes were performed amongst patients with and without history of topical corticosteroid use. RESULTS: A total of 240 patients (406 eyelids) met study criteria, of which 36 patients (44 eyelids) had history of topical corticosteroid use. Mean preoperative margin reflex distance was 0.20 mm and 0.58 mm for topical corticosteroid and non-corticosteroids users (p = 0.01). Mean preoperative levator function was 9.78 mm and 10.38 mm for topical corticosteroid and non-corticosteroid users (p = 0.02). The rate of ptosis repair failure was 30% and 16% in patients with and without a history of topical corticosteroid use (odds ratio 2.25, 95% confidence interval 1.10-4.55; p = 0.03). The rate of recurrence per surgical type in eyelids with and without history of topical corticosteroid use was: external levator advancement/resection 11/27 (41%) and 48/266 (18%) (odds ratio = 3.12, confidence interval 1.36-7.15 0; p = 0.01); Müller muscle conjunctival resection 2/17 (12%) and 9/96 (9%) (odds ratio 1.29, confidence interval 0.25-6.56; p = 0.76). CONCLUSIONS: Topical corticosteroid use is associated with more severe presenting ptosis and increased rates of ptosis repair failure. Compared to Müller muscle conjunctival resection, there is a significantly higher rate of ptosis repair failure in patients undergoing external levator advancement/resection.


Assuntos
Blefaroplastia , Blefaroptose , Corticosteroides , Adulto , Blefaroptose/cirurgia , Humanos , Músculos Oculomotores/cirurgia , Estudos Retrospectivos
14.
Orbit ; 40(1): 39-43, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32172614

RESUMO

Purpose: To report the efficacy of polytetrafluoroethylene (PTFE) frontalis suspension for blepharospasm with eyelid apraxia and postoperative botulinum toxin requirements. Methods: Retrospective chart review of patients with blepharospasm and eyelid apraxia who underwent frontalis suspension. The primary outcome was a surgical success, defined by surgeon- and patient-reported success in postoperative eyelid opening. Comparative statistical analyses of botulinum toxin dosage and treatment intervals were performed amongst patients before and after frontalis suspension ptosis repair. Results: Five patients (10 eyelids) met the study criteria, of which 40% were female. Mean age was 63.2 years. All patients had successful surgical outcomes based on physician-reported and patient reported satisfaction with the postoperative eyelid opening. Average follow-up was 14 months. Preoperative botulinum toxin treatments averaged 80.4 units (range 32-110, SD 33.2) to the periocular region over an average of 9.6-week intervals. Postoperative botulinum toxin treatments averaged 61.4 units (range 24-110, SD 34.7) to the periocular region over an overage of 9.8-week intervals. No patients experienced postoperative exposure keratopathy, extrusion of the sling, or postoperative infection. Conclusions: Frontalis suspension using PTFE suture in the setting of blepharospasm with eyelid apraxia was found to be a safe and effective procedure. Frontalis suspension in this population is not a substitute for botulinum toxin treatment but may allow for reduced treatment dosage. Frontalis suspension appears to increase patient functionality with improved eyelid opening in patients with blepharospasm with eyelid apraxia.


Assuntos
Apraxias , Blefaroptose , Blefarospasmo , Toxinas Botulínicas , Politetrafluoretileno/uso terapêutico , Blefaroptose/cirurgia , Blefarospasmo/tratamento farmacológico , Toxinas Botulínicas/uso terapêutico , Pálpebras/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
15.
Environ Microbiol ; 22(7): 2664-2679, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32162766

RESUMO

Bacteria in nature often encounter non-antibiotic antibacterials (NAAs), such as disinfectants and heavy metals, and they can evolve resistance via mechanisms that are also involved in antibiotic resistance. Understanding whether susceptibility to different types of antibacterials is non-randomly associated across natural and clinical bacteria is therefore important for predicting the spread of resistance, yet there is no consensus about the extent of such associations or underlying mechanisms. We tested for associations between susceptibility phenotypes of 93 natural and clinical Escherichia coli isolates to various NAAs and antibiotics. Across all compound combinations, we detected a small number of non-random associations, including a trio of positive associations among chloramphenicol, triclosan and benzalkonium chloride. We investigated genetic mechanisms that can explain such associations using genomic information, genetic knockouts and experimental evolution. This revealed some mutations that are selected for by experimental exposure to one compound and confer cross-resistance to other compounds. Surprisingly, these interactions were asymmetric: selection for chloramphenicol resistance conferred cross-resistance to triclosan and benzalkonium chloride, but selection for triclosan resistance did not confer cross-resistance to other compounds. These results identify genetic changes involved in variable cross-resistance across antibiotics and NAAs, potentially contributing to associations in natural and clinical bacteria.


Assuntos
Antibacterianos/farmacologia , Desinfetantes/farmacologia , Farmacorresistência Bacteriana/genética , Escherichia coli/efeitos dos fármacos , Metais Pesados/farmacologia , Compostos de Benzalcônio/farmacologia , Cloranfenicol/farmacologia , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/tratamento farmacológico , Humanos , Testes de Sensibilidade Microbiana , Triclosan/farmacologia
16.
Ophthalmic Plast Reconstr Surg ; 36(3): e65-e68, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31880682

RESUMO

Inflammatory myofibroblastic tumor is a mesenchymal neoplasm, commonly seen in the lung and abdominopelvic region of children. The authors present an 8-month-old female with a 2-month history of left-sided proptosis. Examination was significant for left-sided proptosis, a left exotropia and hypotropia, left supraduction and adduction deficits, and left optic disc elevation. MRI imaging revealed an extraconal left superomedial orbital mass with globe displacement and proptosis. Left anterior orbitotomy with excisional biopsy showed a solid mass composed of an infiltrative proliferation of bland spindle cells in a variably myxoid background with associated perivascular lymphoplasmacytic infiltration. Immunohistochemistry was positive for ALK-1 and CD34 and demonstrated focal positivity for S100. Fluorescence in-situ hybridization showed an additional copy of the 3'ALK gene (46%) in interphase cells examined. Next generation targeted sequencing found a DCTN1/ALK fusion. Findings were consistent with inflammatory myofibroblastic tumor. To the authors' knowledge, this is one of the largest primary orbital inflammatory myofibroblastic tumors in the youngest reported patient.


Assuntos
Neoplasias de Tecido Muscular/diagnóstico , Órbita , Biomarcadores Tumorais , Criança , Feminino , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Lactente , Órbita/patologia
17.
Ophthalmic Plast Reconstr Surg ; 36(4): 385-389, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31917766

RESUMO

PURPOSE: Intravenous antibiotic prophylaxis is used for many clean-contaminated surgeries or clean surgeries with an implant, but its value for clean orbital surgery has not been determined. This study investigated infection risks and adverse effects related to antibiotics in patients undergoing orbital surgery. METHODS: A prospective, nonrandomized comparative case series of all patients undergoing orbital surgery with participating surgeons between October 1, 2013, and March 1, 2015. Types of surgery, antibiotic regimens, corticosteroid use, antibiotic side effects, and surgical site infections (SSIs) were entered into an electronic database and subsequently analyzed. Cases in which patients received postoperative oral antibiotics were analyzed separately. RESULTS: Of 1,250 consecutive orbital surgeries, 1,225 met inclusion criteria. A total of 1208 patients were included in the primary analysis: 603 received no antibiotic prophylaxis (group A), and 605 received a single dose of intravenous antibiotic (group B). Five patients (0.42%) developed an SSI, 3 in group A and 2 in group B. The difference in SSI rates was not statistically significant between the 2 groups (p = 0.66). Antibiotic prophylaxis, alloplastic implants, paranasal sinus entry, and corticosteroid use were not associated with differences in SSI rates. All SSIs resolved on a single course of oral antibiotics; an implant was removed in 1 case. There were no complications associated with a single dose of intravenous prophylaxis. However, 12% of 17 patients (group C) who received 1 week of oral postoperative prophylactic antibiotics developed antibiotic-related complications (diarrhea, renal injury), yielding a number needed to harm of 8.5. CONCLUSIONS: In this large series, antibiotic prophylaxis does not appear to have reduced the already low incidence of SSI following orbital surgery. Given the detriments of systemic antibiotics, the rarity of infections related to orbital surgery, and the efficacy of treating such infections should they occur, patients undergoing orbital surgery should be educated to the early symptoms of postoperative infection and followed closely, but do not routinely require perioperative antibiotics.


Assuntos
Antibioticoprofilaxia , Infecção da Ferida Cirúrgica , Antibacterianos/uso terapêutico , Humanos , Estudos Prospectivos , Estudos Retrospectivos , Infecção da Ferida Cirúrgica/prevenção & controle
18.
Appl Environ Microbiol ; 85(4)2019 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-30530714

RESUMO

Bacterial pathogens that carry antibiotic resistance alleles sometimes pay a cost in the form of impaired growth in antibiotic-free conditions. This cost of resistance is expected to be a key parameter for understanding how resistance spreads and persists in pathogen populations. Analysis of individual resistance alleles from laboratory evolution and natural isolates has shown they are typically costly, but these costs are highly variable and influenced by genetic variation at other loci. It therefore remains unclear how strongly resistance is linked to impaired antibiotic-free growth in bacteria from natural and clinical scenarios, where resistance alleles are likely to coincide with other types of genetic variation. To investigate this, we measured the growth of 92 natural and clinical Escherichia coli isolates across three antibiotic-free environments. We then tested whether variation of antibiotic-free growth among isolates was predicted by their resistance to 10 antibiotics, while accounting for the phylogenetic structure of the data. We found that isolates with similar resistance profiles had similar antibiotic-free growth profiles, but it was not simply that higher average resistance was associated with impaired growth. Next, we used whole-genome sequences to identify antibiotic resistance genes and found that isolates carrying a greater number of resistance gene types grew relatively poorly in antibiotic-free conditions, even when the resistance genes they carried were different. This suggests that the resistance of bacterial pathogens is linked to growth costs in nature, but it is the total genetic burden and multivariate resistance phenotype that predict these costs, rather than individual alleles or mean resistance across antibiotics.IMPORTANCE Managing the spread of antibiotic resistance in bacterial pathogens is a major challenge for global public health. Central to this challenge is understanding whether resistance is linked to impaired bacterial growth in the absence of antibiotics, because this determines whether resistance declines when bacteria are no longer exposed to antibiotics. We studied 92 isolates of the key bacterial pathogen Escherichia coli; these isolates varied in both their antibiotic resistance genes and other parts of the genome. Taking this approach, rather than focusing on individual genetic changes associated with resistance as in much previous work, revealed that growth without antibiotics was linked to the number of specialized resistance genes carried and the combination of antibiotics to which isolates were resistant but was not linked to average antibiotic resistance. This approach provides new insights into the genetic factors driving the long-term persistence of antibiotic-resistant bacteria, which is important for future efforts to predict and manage resistance.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Escherichia coli/genética , Genes MDR/genética , Alelos , Desinfetantes/farmacologia , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/microbiologia , Variação Genética , Metais/farmacologia , Testes de Sensibilidade Microbiana , Fenótipo , Filogenia , Sequenciamento Completo do Genoma
19.
Curr Opin Ophthalmol ; 30(5): 349-355, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31261188

RESUMO

PURPOSE OF REVIEW: This study is a review of recent literature in the diagnosis and management of preseptal cellulitis, orbital cellulitis and dacryocystitis, including causative organisms, diagnosis and medical or surgical therapy and potential complications. RECENT FINDINGS: Advances in vaccination against Haemophilus influenzae B have resulted in a shift in the most common causative organisms of preseptal and orbital cellulitis. Management of orbital cellulitis has been advanced by adjuvant corticosteroids, and subperiosteal abscess volumes of more than 1250 ml has been shown as predictive for requiring potential surgical intervention. SUMMARY: Periorbital infections require prompt evaluation and management. Although the infectious organisms in both preseptal and orbital cellulitis include Staphylococcus/Streptococcus species, management may differ significantly on the basis of the nidus of infection, presenting signs and symptoms, and response to initial medical management.


Assuntos
Abscesso/microbiologia , Dacriocistite/microbiologia , Infecções Oculares Bacterianas/microbiologia , Celulite Orbitária/microbiologia , Abscesso/diagnóstico , Abscesso/tratamento farmacológico , Antibacterianos/uso terapêutico , Bactérias/isolamento & purificação , Criança , Pré-Escolar , Dacriocistite/diagnóstico , Dacriocistite/tratamento farmacológico , Infecções Oculares Bacterianas/diagnóstico , Infecções Oculares Bacterianas/tratamento farmacológico , Feminino , Humanos , Masculino , Celulite Orbitária/diagnóstico , Celulite Orbitária/tratamento farmacológico
20.
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