Fortified antibitoics

[Richard_Hom]

Dear Dr. Doan and List,

A 67 year old HF presents from the Emergency room with a 7 day history of red and painful left eye. She is a resident of a "senior home" and had been bedridden 1 week before with a mild URI . She is photobphic with no discharge. No history of trauma and she is not a contact lens wearer.

Physical examination shows that PH vision is OD 20/25 and OS HM 5 feet. There is a 4mm central corneal "ulcer" that is centrally excavated and traps fluoroscein. The anterior chamber shows 4+ flare without cells. The right eye is quiet but shows mutliple superficial corneal opacities (CFB? ulcers?).
The corneal sensitivity is normal for both eys.
Culture shows coagulase negative and shows resistance to ciprofloxacin and its relatives.

A 3 day course of Zymar q3 hrs did not improve the situation. It actually increased in size by 2x.

Questions:

1. At what point would you consider fortified antibiotics?
2. If so, which?
3. Would you start wtih Tobramycin 9mg/ml? or not?
4. When would you consider a corneal biopsy?



Thanks,
RIchard_Hom

---

Members don't see this ad.

 

[exmike]

are you having the board do your homework for you? heehee

 

[Richard_Hom]

Originally posted by exmike
are you having the board do your homework for you? heehee

Dear exmike,

I'd like to hear some of the practicing doctors provide me with "clinical" information. I just saw this patient two weeks ago with the above problem and wanted to hear of some other thoughts on this.


Richard_Hom

 

[GlaucomaMD]

Richard,

For a large central corneal ulcer such as the one you described, I would have started the fortified antibiotics the moment I saw her.

Obviously, we'd like to see the picture or at least more detailed description; do you feel certain that this is an infectious process? (culture may represent normal flora for this patient) I have seen many nursing home patients with horrible exposure keratopathy...

If you believe this gram-positive is the pathogen, I would treat with fortificed Ancef. If I am worried about methicillin-resistance (likely in nursing home population), I would strongly consider fortified Vancomycin instead.

I use fortified Gent/Tobra if the pathogen is gram-negative (or until I have the gram stain result); the concentration should be 14 mg/mL for both fortified Gent & Tobra.

If the corneal ulcer has really doubled as you say (8 mm diameter!), I might be biopsing the cornea NOW.

The cases I use quinolones are for small (certainly not 4 mm) or peripheral ulcers. Unless the lesions look very benign, I would have started it q1h.

Just my 2 cents. Hope it helps...

 

[Andrew_Doan]

I need to know more information.

Does the patient have any previous medical or ocular diagnoses? Is there a possibility for exposure keratopathy? Any history of trauma? Was an echo performed to rule-out endophthalmitis?

Is there a corneal infiltrate on exam? Was there a ring infiltrate? Was it purulent?

Coag negative staph may be a contaminant. What was the gram stain? Was a fungal stain performed? How were the cultures collected and grown? We take several culture specimens and grow them on: Blood agar, Chocolate Agar, Anaerobic culture, Thioglycollate broth, and Sabouraud's agar for fungi. I would reculture again if the patient is not responsive to therapy. Also, consider doing confocal microscopy to detect acanthamoeba cysts and trophozoites.

I'd also consider performing a corneal biopsy.

I'd also consult a cornea specialist, and while waiting, start the patient on Q1hour drops of fortified tobramycin (14 mg/ml) and fortified vancomycin (25 mg/ml).

If the cornea does not appear to be infected, then auto-immune and systemic collagen-vascular diseases should be considered.

Furthermore, this is a case that needs daily follow-up, possible hospitalization for hourly drops around the clock, and consultation with a cornea specialist.

 

[Richard_Hom]

Originally posted by Andrew_Doan
I need to know more information.

Does the patient have any previous medical or ocular diagnoses? Is there a possibility for exposure keratopathy? Any history of trauma? Was an echo performed to rule-out endophthalmitis?

Is there a corneal infiltrate on exam? Was there a ring infiltrate? Was it purulent?

Coag negative staph may be a contaminant. What was the gram stain? Was a fungal stain performed? How were the cultures collected and grown? We take several culture specimens and grow them on: Blood agar, Chocolate Agar, Anaerobic culture, Thioglycollate broth, and Sabouraud's agar for fungi. I would reculture again if the patient is not responsive to therapy. Also, consider doing confocal microscopy to detect acanthamoeba cysts and trophozoites.

I'd also consider performing a corneal biopsy.

I'd also consult a cornea specialist, and while waiting, start the patient on Q1hour drops of fortified tobramycin (14 mg/ml) and fortified vancomycin (25 mg/ml).

If the cornea does not appear to be infected, then auto-immune and systemic collagen-vascular diseases should be considered.

Furthermore, this is a case that needs daily follow-up, possible hospitalization for hourly drops around the clock, and consultation with a cornea specialist.

1. Discharge is not purulent
2. The patient is a poor historian but I noticed multiple corneal opacities in the fellow eye for which no apparent information could either be elicited from the patient or from any prior medical records on the patient. The patient was quite agitated upon presentation and spoke "illiterate" Spanish which caused the interpreter some problems.
3. Fungal stain was not done
4. Culture was gathered with a sterile cotton-tipped applicator and placed in a tube. No culture plates were available at the clinic (last patient of the day).
5. The ulcer was white all the way from the center to the edge. There was a central depression. The edges were slightly rolled.
6. No corneal infiltrate seen.
7. Successive cultures were taken but I don't know the results yet.
8. Considered exposure keratitis b/c the patient did demonstrate rapid tear break up time in the right eye (could have been the reflex tearing of the OS). No staining at all in the OD.
9. No h/o trauma (per social worker who visited site and queried other personnel there)
10. No vitreous cells or flare on dilated fundus exam.
11. No anterior segment imaging capability at this clinic.
12. Patient was also given a referral for primary medical care. That appointment is pending.
13. Care to this patient was in conjunction with the on-call ophthalmologist. Continuing care is now in their hands.
14. I saw the patient yesterday (14 days after presentation) and the corneas appear almost clear but there is still a significant depression centrally. There is still some punctate staining centrally. I asked the patient to continue Tobramycin-fortified 9mg/ml q1 hr and Zymar q3 hrs until the next opthhalmologic visit in 3 days (Monday).

Thanks so much for your insight.
Richard_Hom

 

[Floxin]

coagulase negative.... I would do Augmentin 875/125 mg , clavulanic acid replicates the quinolones ability to upset the extracellular matrix/bio film .If quinolones are ineffective then you must treat with an alternative medication that would replicate the same pharmacotherapeutics physiological effects in similar board spectrum , or I.V penicillin/tazobactam . So change the chemical make-up. You could also add neomycin 500mg 1/2 dose to prevent kidney damage as partial treatment for synergistic effect however that option is souring as some people are allergic to neomycin. Alternative would also be Sulfa, but also allergies are concern sooo rifampin is the best option as a dual combo and the antibiotic is C Diff preventive considering C Diff has known sensitivity to RNA polymerase or low threshold is know.

Corneal ulcer makes me suspect RA and auto-immunodeficiency doesn't sound like an infection, which would explain the reason for the URI as being opportunistic. You usually see a Enbrel+Methotrexate injection to reverse the damage as short term, but debate on immunoglobulin specific long term treatment is unknown as each medication is designed different to tackle either the TNF, IL-interleukin or T cell maturity.

I wouldn't do vancomycin or tobramycin fortified that is redundant to oral antibiotics, we just established zymar didn't work........ just save the patient wallet ; there a chance the patient is also on beta blockers (used also for panic attacks if the patient is in a housing unit, there mental problems) and the destroyed capillaries , this would have adverse effect on the medication effectiveness creating a coagulating effect therefore would not allow the full potential effectiveness of the antibiotic. If you really want to be safe Merrem, or IVANZ would be the best option in I.V realm , if you honestly wanted to start a pick-line.

you could do a biopsy to be safe and its reimbursable by insurance meaning its an acceptable producer under that circumstance , but you could also risk adding a new infection if done improperly.

Even if the ulcer due to an infection, lets say syphilis hypothetically , still would be treated with a proper gram-negative spectrum aka Augmentin as bicillin G may not work with 1 injection and Beta lactam antibiotics decays the tetracycline.

you could also add klor-con or magnesium to treat the damaged area . I could imagine the damage to nerves would cause some sort of long term electrical problem or lack of proper electrolytes synthesis

honestly there not enough patient information to have direct treatment,
But my question is where did you culture? and why? and how deep?
Has the patient have known history of cardiovascular disease
What is the patient mental status?

 

[Eyefixer]

Really? 13 years later?


Sent from my iPhone using SDN mobile

 

[DrZeke]

LOL


Sent from my iPhone using SDN mobile

 

[Floxin]

Really? 13 years later?


Sent from my iPhone using SDN mobile

Sorry I'm a medicine nerd , your topic sparked great interest

 

[Slide]

Wow talk about major thread necromancy.

BTW Floxin, your thoughts are good from a medicine perspective but for corneal infections, oral systemics have little place as first line therapy unless the ulcer is super deep or there is evidence or suspicion of full out endophthalmitis. The history is very classic for exposure leading to a corneal abrasion that got infected, so I think it's safe to hold off on any zebra work-ups.