OcuLearning › Uveitis

Endogenous Bacterial Endophthalmitis

CRITICAL — Uveitis

Symptoms

decreased vision in an acutely ill or septic patient

ocular pain and redness

floaters and photophobia

recent hospitalization, indwelling catheter, or systemic procedure (e.g., heart valve, gi/gu surgery)

history of iv drug use

note: no history of recent intraocular surgery (distinguishes from exogenous)

Clinical Findings

Signature findings

  • chorioretinal abscesses: cream-yellow round elevations at the choroid/retina level
  • severe vitritis, dense debris, and absent red reflex
  • anterior chamber cell, flare, and hypopyon
  • iris microabscesses
  • roth spots: white-centered flame hemorrhages (septic emboli)
  • advanced signs: corneal edema, chemosis, proptosis, and restricted motility (panophthalmitis)
  • bilateral involvement in ~25% of cases

Organism-source patterns

  • klebsiella pneumoniae: associated with pyogenic liver abscess in asian diabetic patients; extremely poor prognosis
  • staphylococcus aureus / streptococcus: associated with endocarditis, skin/soft-tissue infection, or orthopedic hardware
  • bacillus cereus: associated with iv drug use; causes fulminant globe destruction within 24–48 hours
  • gram-negative rods (e. coli, pseudomonas): associated with urinary or biliary sources
  • neisseria meningitidis: associated with meningococcal sepsis and purpura

Greenwald severity classification

  • anterior focal: localized to iris/ac; best prognosis
  • posterior focal: single chorioretinal abscess; intermediate prognosis
  • anterior diffuse: severe anterior uveitis with hypopyon; guarded prognosis
  • posterior diffuse: widespread retinitis/vitritis; poor prognosis
  • panophthalmitis: entire globe and orbit involvement; often requires enucleation

Etiology

Pathophysiology

  • hematogenous spread of infection from a distant systemic source to the eye

Risk factors

  • diabetes mellitus and immunocompromise
  • iv drug use and endocarditis
  • indwelling catheters, central lines, and recent gi/gu or cardiac surgery

Red Flags

ocular inflammation in a septic or acutely ill patient

asian diabetic patients with suspected liver abscess (klebsiella)

fulminant progression in iv drug users (bacillus cereus)

right-sided endocarditis with embolic ocular findings

Investigations

Ocular diagnostics

  • b-scan ultrasound: mandatory if no fundus view to assess vitritis and abscesses
  • vitreous biopsy: highest yield (~60%) for culture
  • anterior chamber tap: lower yield (~20%)

Systemic workup

  • blood cultures (two sets) and urine culture
  • echocardiography (tse or tte) to rule out endocarditis
  • abdominal imaging (ct/mri) to identify occult abscess (especially liver)
  • chest x-ray, cbc with differential, hba1c, and hiv testing
  • lumbar puncture if meningeal signs are present

Treatment

Intravitreal therapy

  • empiric vancomycin and ceftazidime
  • add ampicillin or amphotericin-b if listeria or fungal infection is suspected
  • avoid amikacin due to risk of macular infarction

Systemic therapy

  • iv antibiotics with vitreous penetration (e.g., fluoroquinolones, linezolid, meropenem)
  • tailor antibiotics to the identified systemic source and culture results

Surgical intervention

  • urgent pars plana vitrectomy (ppv) for severe vitritis (va <20/400) or non-response to tap-and-inject
  • evisceration or enucleation for blind, painful, uncontrolled infection

Differential Diagnosis

  • endogenous fungal endophthalmitis (candida, aspergillus)
  • viral retinitis
  • noninfectious uveitis (sarcoidosis, pars planitis)
  • neoplastic conditions (masquerade)

Related Uveitis Conditions