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Study Provides Insights Into Acute Bacterial Dacryocystitis

In a study published in International Ophthalmology, researchers at the Royal Adelaide Hospital in South Australia examined the microbiology of acute bacterial dacryocystitis to create a comprehensive microbiological profile of this condition as a way to help eye care practitioners in the empirical selection of antibiotic therapies. (As many of you know, acute bacterial dacryocystitis is an inflammatory bacterial condition that affects the eye's lacrimal drainage system and can pose risks to a patient's visual system if treated improperly.)

The study took place over 5 years and included 43 patients (65% female; mean age 64 years) with acute dacryocystitis. Their most common clinical features were pain (74%) and swelling (70%). Organisms were identified in 49% of patients. So, what bacteria were prominent?

Staphylococcus aureus (42%)
Streptococcus species (19%)
Escherichia coli (8%)
Aggregatibacter species (8%)
Morganella morganii (4%)
Enterobacter cloacae (4%)
Hafnia alvei (4%)
Mixed anaerobes (4%)
E. coliforms (4%)
Pseudomonas aeruginosa (4%)

The most frequently prescribed empirical antibiotics were amoxicillin-clavulanic acid (50%), flucloxacillin (33%), and cefalexin (18%).

For acute bacterial dacryocystitis caused by S. aureus or Strep species, the researchers discovered that these bacteria were most sensitive to treatment with vancomycin, clindamycin, and cefalexin.

They also found that, most often, Gram-positive organisms were the dominant cause of acute dacryocystitis cases.

OUTSIDE THE LANE

Space Travel: Not So Eye-Friendly

Space travel has been a hot topic these past few years, as Earth’s richest individuals seem to be reaching toward the stars in an effort to gain bragging rights. Not to mention our own government has created and implemented a service branch called Space Force. The entire process of interstellar travel presents numerous unique challenges to astronauts. This article highlights a few of these.

The term Spaceflight-Associated Neuro-Ocular Syndrome (SANS) describes the visual disturbances astronauts experience during extended missions. These disturbances include blurred vision, swelling of the optic nerve, and changes in visual acuity. The term SANS itself is a collective name for all these eye-related issues that researchers believe result in the fluid shifts within the human body that cause increased intracranial pressure and altered blood flow. The exact mechanisms behind SANS are unknown; however, research into the topic seems to be ramping up.

In addition to SANS, the issue of microgravity has a large effect on the body. Like SANS, microgravity causes bodily fluids to redistribute, triggering fluctuations in blood flow and pressure, resulting in visual disturbances and optic nerve swelling.

Additionally, without the earth’s atmosphere to protect them, the sun’s radiation is a huge concern to astronauts’ eye health. It has been proven that cosmic rays and solar particles have a damaging effect on retinal cells. Research has shown that astronauts’ retinas undergo alteration and damage during space travel, resulting in color vision changes and contrast sensitivity reduction. Not only that, but prolonged exposure also increases the risk of cataracts.

My Two Cents

I have often wondered how space travel affects the human eye, and this article explains things wonderfully. Due to microgravity, fluid shifts, and radiation exposure, the human eye takes quite a beating in space. Hopefully, ongoing research is being done by optometrists much smarter than me that can help mitigate this damage.

CAN YOU RELATE

Well, Optometry’s Meeting (OM) has come and gone and as usual, there were so many interesting exhibits and announcements made during those few short days. Nashville also lived up to the hype that it had developed at last year’s MOD Live Conference, with many of us hitting up Broadway and exploring more than a few honky tonks.

A few of my favorite things from OM 2024 were just how invested many of our industry partners are in optometry. From CooperVision’s schoolhouse on the exhibit floor to Bausch + Lomb seemingly being everywhere with all its new product lines (their CEO Brent Saunders is an absolute machine!), it was so encouraging to see all of the various support optometry is getting. From a pharmaceutical standpoint, I was incredibly impressed with Lenz Therapeutics’ phase 3 data for its 1.75% aceclidine presbyopia drop (LNZ100). I know, I know—another presbyopia drop; however, this one feels different when you look at the data. The presentation on Thursday night was extremely impressive, and massive kudos to the whole Lenz Therapeutics team. Not only that, but its marketing messaging was all over the convention center, grabbing the attention of nearly everyone in attendance. Another impressive innovation (in my opinion) goes to B+L. I’m incredibly excited about its new Blink NutriTears supplement for Dry Eyes, and I started taking it myself. It’s dosed once daily and, if practical, could bring more patients into the fold for supplementation. We do have incredible options with products such as HydroEye (ScienceBased Health) and De 3 Omega Benefits (Physician Recommended Nutriceuticals); however, both of those supplements require multiple pills per day, resulting in compliance burnout in some of my patients.

Now that this conference has wrapped up, it’s time to look forward to our next trip to Nashville for MOD Live in September. If you missed Optometry’s Meeting and would like to line dance your way over to Nashville, see the sights, and get world-class continuing education, click here to register.