PubMed Health⌕ Search

Biomedical subjects

Consuelo Ferrer

Publications and source records attributed to Consuelo Ferrer.

10 recordsLinked to original sources

Polymerase chain reaction and DNA typing for diagnosis of infectious crystalline keratopathy.

A 63-year-old man developed infectious crystalline keratopathy (ICK) in his right eye 1 year after phacoemulsification. The white peripheral lesion was adjacent to the corneal phacoemulsification incision. Infiltrates in the form of creamy-white, midstromal branching, needle-like opacities without evidence of inflammatory cells were noted. A corneal biopsy by double lamellar flap was done and studied by 3 techniques: microbiological culture, stain, and polymerase chain reaction (PCR). Fungal and bacterial PCR were positive. A second sample was necessary to obtain a positive stain and culture. The DNA sequence analysis showed Candida parapsilosis and Staphylococcus aureus as the causal agents of the crystalline keratopathy. Treatment was started with amphotericin B 1% and cefazolin 6 times a day, and systemic voriconazole was recommended. This is the first reported case of ICK after cataract surgery. Polymerase chain reaction amplification and subsequent DNA typing were useful tools in detecting and identifying the ocular pathogens involved in this case.

Anti-Bacterial Agents↗

[Molecular biology in the diagnosis of deep-seated candidiasis in the critically ill non-neutropenic patient].

Candida infections are an important cause of morbidity and mortality in critically ill patients. Rapid detection of the yeast in blood and other tissues by molecular biology methods has been the goal of some recent studies. An analysis of the sensitivity and specificity of these methods assayed in clinical specimens from critically ill and other patients is carried out. PCR amplification of ribosomal genes and their internal spacers showed a higher sensitivity than culture based methods. A standardization of most of the methodological steps in molecular methods is needed. Real time PCR with fluorescent probes seems to be the most interesting proposal. It has the advantage of the possible quantification of fungal presence in tissues and minimizes the samples' contamination risk.

Candida↗

Hyaluronic acid combined with mannitol to improve protection against free-radical endothelial damage: experimental model.

PURPOSE: To evaluate the protective properties of combined sodium hyaluronate 2% and mannitol 0.5% (Visiol) on the corneal endothelium in the presence of oxidative stress induced by hydrogen peroxide (H(2)O(2)). SETTING: Instituto Oftalmológico de Alicante, Universidad Miguel Hernández, Alicante, Spain. METHODS: This was an exploratory randomized controlled parallel-group, masked-assessor study of 3 sodium hyaluronate-based ophthalmic viscosurgical devices (OVDs): Visiol, Healon (sodium hyaluronate 1%), and Viscoat (sodium hyaluronate 3%-chondroitin sodium 4%). The OVDs were tested for protective effects on the endothelium following oxidative stress induced by H(2)O(2) at increased concentrations: control (lactated Ringer's solution), 1 mM, 10 mM, and 100 mM. Groups without OVD were used as controls at the same concentrations of peroxide. Each animal received the same treatment in both eyes (10 eyes per group). Endothelial cell lesion was assessed using the Janus green photometry absorbance technique. RESULTS: At 10 mM peroxide concentration, the value of endothelial cell lesion was significantly lower in the Visiol (16.8%, P=.0056), Healon (22.2%, P=.0302), and Viscoat (21.6%, P=.0336) groups than in the control group (29.4%, no OVD). There was a trend in favor of Visiol to more efficiently reduce cell lesions of the endothelium, than Healon (P=.055) and Viscoat (P=.1013). Values of endothelial cell lesion at peroxide concentrations of 1 mM and 100 mM showed the same trends than those observed at 10 mM. CONCLUSIONS: All of the OVDs tested efficiently reduced endothelial lesions against free radicals compared with the control group in which no OVD was used. The following sequence for the efficacy of endothelial cell protection was established: Visiol>Viscoat>Healon>no OVD.

Animals↗

Endophthalmitis caused by Fusarium proliferatum.

Fusarium proliferatum caused endophthalmitis after cataract surgery. Diagnosis was established by classical microbiology and molecular biology methods (PCR and DNA typing). The treatment with local amphotericin B, oral ketoconazole, and topical natamycin was successful.

Aged↗

Unusual anaerobic bacteria in keratitis after laser in situ keratomileusis: diagnosis using molecular biology methods.

Laser in situ keratomileusis (LASIK) was performed in the left eye of a 57-year-old man for residual ametropia after phacoemulsification. The patient was given topical tobramycin and a corticosteroid for 1 week postoperatively. Fifteen days later, he developed 3 corneal infiltrates beneath the flap with a gas bubble, suggesting an anaerobic infection. Tobramycin and ofloxacin were administered every 2 hours, but the condition worsened. Corneal scrapings were taken from beneath the flap for microbiological cultures and a polymerase chain reaction (PCR) test. The PCR amplification was negative for fungi and mycobacteria and positive for bacterial DNA. Sequence analysis showed Propionibacterium granulosum as the causal agent, but cultures were negative. Treatment with vancomycin and cefazolin led to clinical improvement, with resolution of corneal infiltrates. Anaerobic microorganisms can cause keratitis after LASIK. Polymerase chain reaction amplification and DNA typing can help detect microorganisms involved in these ocular infections.

Bacterial Typing Techniques↗

Postoperative Corynebacterium macginleyi endophthalmitis.

A 72-year-old man with chronic endophthalmitis who received steroid treatment for 3 months came to our center. Sterile endophthalmitis after cataract extraction had been diagnosed. Aqueous samples including smears, classic cultures, and polymerase chain reaction were taken for microbiological study. Amplified DNA was sequenced to identify the pathogen. Polymerase chain reaction amplification was positive for bacteria. Sequence analysis showed Corynebacterium macginleyi as the causal agent in 48 hours. The culture and smear stains from the ocular samples were negative. The patient was successfully treated with vancomycin. Polymerase chain reaction and subsequent DNA-typing were useful in detecting the microorganisms that caused the chronic endophthalmitis.

Aged↗

Rapid molecular diagnosis of posttraumatic keratitis and endophthalmitis caused by Alternaria infectoria.

The first case of Alternaria infectoria ocular infection is reported. Keratitis and endophthalmitis developed after eye-perforating trauma from a lemon tree branch. Two months after surgery and empirical steroid and antibiotic treatment, diagnosis by molecular methods was performed. PCR amplification was positive for a fungus after 4 h. Antifungal treatment with amphotericin B and fluconazole was initiated immediately. DNA sequence analysis showed Alternaria infectoria to be the causal agent. After topical and systemic administration of antifungal treatment, ocular inflammation disappeared and visual acuity improved. DNA typing was found to be a useful tool to achieve early identification of the causal agent.

Aged↗

Polymerase chain reaction diagnosis in fungal keratitis caused by Alternaria alternata.

PURPOSE: To contribute toward assessing the effectiveness of polymerase chain reaction as a rapid method in diagnosis of torpid keratitis caused by opportunistic fungi. METHODS: Interventional case report. A 50-year-old man with a corneal abscess in the right eye treated for a period of 6 months with different combinations of broad-spectrum antibiotics and steroids was referred to our center. Corneal scraping was taken for microbiological study, including classic cultures and polymerase chain reaction. Amplified DNA was sequenced to identify the pathogen. RESULTS: Polymerase chain reaction amplification was negative for Acanthamoeba species and positive for fungi. The sequence analysis showed Alternaria alternata as the causal agent in 24 hours. Cultures confirmed the identification in 10 days. CONCLUSION: Polymerase chain reaction amplification with subsequent DNA-typing was revealed to be a useful method for detection of ocular pathogens such as A. alternata involved in cases of torpid keratitis, even in the presence of broad-spectrum antimicrobial therapy.

Abscess↗