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Updated: Jan 19, 2026
The Hydrogen Atom: Bohr Model and Balmer Series - Concept
Endogenous Serratia marcescens panophthalmitis: A case series
Mark P Breazzano1,2, Gowtham Jonna1,3, Niraj R Nathan1,4
1Vanderbilt Eye Institute, Department of Ophthalmology and Visual Sciences, Vanderbilt University Medical Center, Nashville, TN, USA.
Purpose:
- Two rare and unusual cases of endogenous panophthalmitis from Serratia marcescens are presented with mechanisms for infection explored. - The first patient had history of intravenous drug use (IVDU) without any medical implants. The second patient, in addition to IVDU, had a history of end-stage renal disease with upper extremity arteriovenous fistula graft infection from Serratia marcescens confirmed by wound culture. One patient had a history of licking the needles prior to IV drug injection. Clinical exam in both cases revealed light perception vision, relative afferent pupillary defect, periorbital edema with limited extraocular motility, and hypopyon in the affected eyes. Cultures from the anterior chamber aspirate were positive for Serratia marcescens in the first case and demonstrated Gram-negative rods in the second. Attempted vitreous aspiration was unsuccessful at obtaining specimens. Computed tomography demonstrated orbital fat stranding without abscess, and histopathology showed intense neutrophilic infiltration in all layers of enucleated specimen in case one.
Conclusions And Importance:
Needle licking may be an underappreciated mechanism for endogenous endophthalmitis in intravenous drug users. This report includes the first case in the literature, to authors' knowledge, of non-nosocomial endogenous Serratia marcescens panophthalmitis with orbital cellulitis. The second case illustrates a rare consequence of the rise in arteriovenous fistula placement and dialysis across the United States, which may predispose to future cases of endogenous Serratia marcescens endophthalmitis. This series supports previous observations of Serratia marcescens endogenous endophthalmitis exhibiting a generally poor visual prognosis.
Insights
Needle licking is a potential cause of endogenous endophthalmitis in intravenous drug users. Arteriovenous fistula grafts in patients with end-stage renal disease also pose a risk for this rare infection.
Area of Science:
- Ophthalmology
- Infectious Diseases
- Microbiology
Background:
- Endogenous panophthalmitis is a severe intraocular infection.
- Serratia marcescens is an opportunistic pathogen that can cause serious infections.
Observation:
- Two cases of endogenous panophthalmitis caused by Serratia marcescens in intravenous drug users (IVDU) are presented.
- One patient had a history of needle licking prior to injection, a potential novel transmission route.
- The second patient had an infected arteriovenous fistula graft due to end-stage renal disease.
Findings:
- Both patients presented with severe vision loss, hypopyon, and orbital inflammation.
- Cultures confirmed Serratia marcescens infection in the first case and Gram-negative rods in the second.
- Histopathology revealed intense neutrophilic infiltration in the ocular tissues.
Implications:
- Needle licking may be an underrecognized risk factor for endogenous endophthalmitis in IVDU.
- Arteriovenous fistula grafts represent a potential source for Serratia marcescens endophthalmitis in dialysis patients.
- Serratia marcescens endogenous endophthalmitis typically has a poor visual outcome.
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