A 56-year-old female was admitted to ITU with postoperative pneumonia secondary to Serratia marcescens treated with Imipenem 750 mg b.i.d. i.v. She underwent bowel resection for Crohn's disease 1 week prior to her pneumonia. A month later, she arrested and became comatosed despite resuscitation. She deteriorated, developing renal failure requiring haemofiltration. S. marcescens was grown from sputum and blood cultures and Teicoplanin 400 mg b.i.d. i.v. was started. After 24 h, she developed an acute right red eye.
On examination, there was an afferent pupillary defect, corneal oedema, and hypopyon. There was no fundal view (Figure 1). Examination of her left eye was unremarkable. A diagnosis of endogenous endophthalmitis was suspected and a vitreous tap performed with Ceftazidime 2.25 mg, Vancomycin 1 mg, and Amphotericin 5 μg given intravitreally. In addition, she was given hourly G Cefuroxime 5% and G Gentamicin 1.5%. S. marcescens sensitive to Ceftazidime was isolated from her vitreous and a repeated intravitreal injection of Ceftazidime and Vancomycin were given 72 h later. There was little ocular or systemic improvement and despite aggressive treatment she eventually died of multiple organ failure. An autopsy was declined.
Endogenous endophthalmitis (EE) accounts for 10% of all endophthalmitis.1 Fungi are the most common causal pathogen2 followed by bacteria.1, 3 Risk factors include systemic immunosuppression, sepsis, major surgery, indwelling catheters, and prolonged antibiotic therapy.2 The overall prognosis is poor with useful vision preserved in only 40%, 6 and 7–15% patients die from septicaemia.4, 5
Identifying the underlying cause is paramount. Conjunctival swabs poorly reflect intrinsic eye infection and vitreous tap/biopsy6 should be performed and intravitreal antibiotics administered.
S. marcescens is multiresistant Gram-negative bacillus that can produce a red pigment causing a pink hypopyon.7 To our knowledge, this is the first reported case of S. marcescens pneumonia as a primary source for EE (the lung is the most common site for these pathogens8). Despite appropriate systemic and intravitreal antibiotics, the visual outcome was poor and the patient eventually died. As the incidence of EE (especially Gram-negative infections) appears to be rising,3 then this aggressive organism may become a more common cause for this devastating condition.