If not improvement with topical antibiotics it sounds like a fungal infection. Were microbiology tests positive from corneal scrapings? Topical voriconazole may be indicated and eventually intacamerular and or intrastromal injection of antifungal after microbiology test

I strongly agree with Andrea Leonardi . A PCR for HSV, HZV and acanthoameba could help in diagnosis .

I agree with Andrea...I would try to repeat microbiological testing (corneal scrapings and aqueous humor culture) to see if there is any fungal superinfection, and intracamerular injection of both antibiotics and antifungals..

Have a look at a case I successfully treated some time ago..

http://www.slideshare.net/Barnaclinic/fusarium-keratitis-barnaclinic?from_search=2

There isn't a diagnosis. Unroof the abscess, re-culture and drain.

If no improvement, a conjunctival flap is indicated.

Repeat microbiology testing as indicated above and get sensitivities for antibiotics/-fungals. Systemic treatment may be required.

Depending on where you are located and if in line with local regulations, you might consider cross-linking we patient. You will find about 10 references in MedLine for this new use of cross-linking in therapy-resistent ulcers.

I agree with Andrea Leonardi ,when fungal infection is suspected and smear and culture are negative for fungus repeat scraping or even biopsy is necessary to identify fungal material .I am not agree for aqueous humor culture because usually hypopyon is steril.

for treatment i use Natamycin 5% or Amphotericin B and Voriconazol when it doesn't respond to traditional treatment .

You must think to necrotizing Herpetic interstitial keratitis too.

While I realize that you are dealing with a human cornea, we in veterinary ophthalmology also treat stromal abscesses. In dogs, they are usually bacterial in origin and in horses, they are usually fungal/yeast. If fungal is most likely for humans, I use oral fluconazole and topical 1% voriconazole. Fluconazole is better for yeasts and non Aspergillus and Vori was created for Aspergillus app and less efficacious for Fusarium etc. In dogs, I also use the hyperbaric oxygen therapy chamber, it is awesome for corneal infections and uveitis. Again, I know a veterinary patient is not a human, but corneas tend to be corneas.

I agree with Andrea, Augusto and Merce. I prefer topical and intracameral voriconazole if there is any fungal suspicious. Amniotic membrane transplantation and anti-inflammatory therapy would be added their treatment recommendations.

Thank you very much

I totally agree with Farhad. You can rescrape your pt and consider CXL, especially that after 3 weeks of intense fortified treatment the stroma will most probably show melting.

I would also consider cross-linking..

Cross-linking is effective for fungus, but bacteria??

Rescrape and treat with natamycin 5% and amphotericin b intra stromal. It's very suggestive of mixed infection

I think that a very carefull history of the disease must be taking : if he /she is contact lens wearer , did she/he experience previous corneal abces , did she/ he had any corneal trauma or injury by vegetable meaters , did she/he has been exposed to any type of radiations and for how long ? Also the biological testing from the smears of the abces -conjuctival secretions can be hellpfull . The slit lamp examination with blu filter and fluo dye hellp us to see the extention or the borders of the abces if is localized or focal or stellate . In this case i will consider also the viral corneal abces caused by Herpes Simplex type1 by making lab. Blood test and than propablly confirm the diagnosis . The treatment will be in this case idoxuridine every hour , or trifluridine better it will hellp in preventing recurrences , oral acyclovir 500 mg 5 times daily for 14 days and cycloplegy , lubricant drops preservative free to treat the dry eye . Also we must consider all the cases of non- infectious abces with hypopion and make the proper tests needed to rule out or confirm other diagnosis . I agree that after the resolution of the abces and totally healing of the condition we can consider CXl depending on the etiological factor .

Thank you !

In my opinion the patient will receive topically fortified Tobramycin 14 mg/ml ( add 2cc of Tobramycin for injection( 80 mg) to the Tobrex eye drops 0.3% 5cc vial, prescribe to put each hour, at the same time eye drops Moxifloxacine 0.5%, if not vailable Levofloxacin 0.5% , again each hour, but between both drugs will be 30 min intermission - starting from the morning for example - Tobramycin 8 am, 9 am,10 am, etc.

Moxifloxacin -8.30 am, 9.30 am, 10.30 am, etc.

Besides you can subconjunctival injection of AMIKACIN -0.5 cc

Atropine 1% twice a day

For Staph. aureus is good as a general antibiotic therapy -CEFADROXIL (DURICEF) 1.0 oral 7-10 days or if anavailable -Cefuroxime (ZINNAT) the same dosage

I hope very much that prosed treatment will help your patient.

Good Luck! Looking forward to hear good news from you .

Besides abovementioned Betadine 2.5% 4 times a day

I hope very much that prosed treatment will help your patient.

Good Luck! Looking forward to hear good news from you .

I agree with Guenal. Corneal CXL could be a new interesting way of handling infectious keratitis. CXL treatment is supported by evidence of effectivity in the control of infectious keratitis stopping the progress of corneal melting, but the absence of control groups in the studies published to date, does not allow us to indicate this treatment as immediately feasible. The treatment seems to be more effective in blocking corneal melting in bacteria and Acanthamoeba than in fungus, but the different grades of severity of keratitis and the absence of standardization to evaluate this do not allow us to provide a clear final suggestion. A study to compare CXL with standard topical antibiotic treatment in which the severity of keratitis and the infecting organism are homogeneous is required to clarify and prove its application.

If you are interested in this topic, please read it :

http://www.joii-journal.com/content/3/1/47

I agree with the suggestions on intensified therapy so far. In additon I would like to add the suggestion of performing a chaud penetrating keratoplasty. This of course depends on the severity and localizaton of the ulcus. If it is a defect so deep that will not allow a considerable functional restoration and if it is not peripheral, than PKP may be a good choice, according to my expericne.

In my opiion the best will be topical BESIFLOXACINE if not available MOXIFLOXACINE each hour alternating each hour with TOBRAMYCINE  with intermission 30 min bethweeen two drugs. Orally ZINNAT or Cefadroxil . Good luck !