CORNEA EWAP JUNE 2023 37 could be that people are using steroids more readily. I don’t know, but it seems like it’s a lot more common than it was when I first started practicing years ago.” Care and culturing Both Dr. Beckman and Dr. Majmudar said their corneal ulcer patients are generally referred from other eyecare providers. “As a corneal specialist who practices in a tertiary care environment, the majority of ulcer patients who I see have already seen one or more eyecare providers. More often than not, they have had multiple prior treatments and may not be improving,” Dr. Majmudar said. He said his rule of thumb for referrals is “if you don’t think that you can provide the most appropriate and efficacious care for that patient, send them to someone who can do so.” However, he thinks most corneal ulcers can be effectively managed by non-cornea specialists with a basic understanding of common pathogens in the region and appropriate antibiotic therapy. “A pet peeve of mine is if a patient presents with a presumed contact lens-related infection, treatment should generally be directed toward Pseudomonas,” Dr. Majmudar said. “I’ve seen many patients be treated and ultimately referred to me for failed treatment, but they have been on antibiotics that have very little gram-negative coverage.” Both physicians said that they culture almost all patients with a few exceptions. Dr. Majmudar said he might not culture if the lesion is not too peripheral or small. “My advice would be that any central ulcer should be cultured in order to provide the most effective and appropriate antibiotic treatment to the patient. If the clinical course is not going well, I would recommend reculturing and expanding the culture to include other atypical organisms.” Dr. Beckman said he’ll try to get a culture before antibiotic therapy begins because it can limit the yield of the culture. If that’s not possible, he’ll still get a culture because there will sometimes still be a yield. He also mentioned that if the patient wears contacts and has them in the case, they can be used to culture, or he said that a corneal biopsy could get a specimen if initial cultures remain negative. “In some infections where cultures remain negative and they are not responding to treatment, if the infection is very deep, I may take a suture and pass it through the stroma, through the cornea mid-depth, not into the anterior chamber … so that it tracks deep enough so that I might get a better specimen and use that to culture,” he said. While Gram stains can come back within a day, bacterial cultures can take 3–4 days, and fungal cultures can take a month. Dr. Majmudar pointed out that there are several labs that do PCR testing on a number of pathogens with a swab, rather than culture plates, which he said makes it relatively easy for any practice to do. Treating Dr. Beckman will usually start patients on aggressive antibiotics, a fourth-generation quinolone or fortified antibiotic drops, even if the culture hasn’t come back with a specific pathogen yet. Some patients, depending on severity, will be instructed to use this every hour. Also depending on severity, patients are followed up within the clinic every day or two. Once the epithelium heals, Dr. Beckman said he’ll cut back on treatment but will keep them on drops for a couple of weeks. Antibiotics may be tailored more specifically once the culture comes back. If the culture comes back as a fungus, he’ll begin an antifungal but will also keep them on the antibiotic. If quinolone monotherapy was used initially and isn’t effective, Dr. Beckman said he’ll move on to a combination of fortified antibiotics. Dr. Majmudar said the most commonly prescribed antibiotic for corneal ulcers is moxifloxacin, but it has limited gram-negative coverage. He will start a patient on broad-spectrum fortified antibiotics, including fortified cefazolin or vancomycin and fortified tobramycin. Fungal treatment is dependent on whether it is filamentous or yeast. He said as a primary intervention he would use voriconazole or natamycin for filamentous fungal infections and amphotericin B for yeast infections. Three tips for corneal ulcers from Dr. Beckman 1. Get a history. Always ask about injury, foreign body, contact lens wear, and exposure. “If there is something unusual, then you have to think of unusual things.” 2. Watch patients closely. Look for signs of improvement. Use caution with steroids. If there is secondary inflammation that you have to treat, it’s best to do so once you have the infection under control and know it’s not fungal. 3. Get the epithelium to heal quickly. If a patient isn’t healing, it doesn’t necessarily mean they need more antibiotics. Sometimes it means you need less. Some fortified antibiotics are harsh and can result in a persistent epithelial toxicity.
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