A Case of Bilateral Endogenous Bacterial Endophthalmitis from Streptococcus Pneumoniae Bacteraemia

Lessons from practice Case reports A case of bilateral endogenous bacterial endophthalmitis from Streptococcus pneumoniae bacteraemia

Clinical record

A 55-year-old woman was admitted to an orthopaedic unit of a was not possible on the left eye owing to the severity of the metropolitan hospital in Australia with right shoulder septic corneal haze; however, in the right eye, fundoscopy showed arthritis. She had been experiencing 3 days of right shoulder a vitreous haze. pain, fevers, rigors and delirium. These occurred in the context An urgent assessment by an ophthalmologist found that she had of a right rotator cuff repair 3 months previously. Her bilateral endogenous bacterial endophthalmitis. Despite medical history included hypertension, hypercholesterolemia appearing mostly unremarkable on external inspection, the right and an L4-S1 spinal fusion for lumbar spine degeneration. Her eye was deemed to be in the early stages of infection owing to medications included hydrochlorothiazide, olmesartan and the presence of vitreous haze on fundoscopy. After aqueous atorvastatin. humour samples were taken, she was given bilateral intravitreal On examination, she was febrile with a temperature of 38.9C, antibiotic injections of 1 mg vancomycin and 2 mg ceftazidime. with a painful, erythematous and swollen right shoulder with This was followed up with intravitreal injections of 1 mg movement limited by pain. Her chest and abdominal vancomycin every second day for three further doses. The examinations were normal. Her relevant admission blood test cultures from her shoulder, blood and eyes all grew results were white cell count, 30 Â 109/L (reference interval [RI], Streptococcus pneumoniae. Her antibiotics were changed to IV 4e11 Â 109); neutrophil count, 21.9 Â 109 (RI, 2e8 Â 109); and benzylpenicillin and vancomycin; IV azithromycin was also C-reactive protein level, 438 mg/L (RI, 0e5 mg/L). Platelet, added, as evidence has shown that it has a survival benefitin haemoglobin, uric acid and blood sugar levels were all normal. S. pneumoniae infections.1 Further investigations performed to Her shoulder and chest x-rays were unremarkable. Several sets exclude immunosuppression and locate the source of the of blood cultures as well as a shoulder aspirate showed gram- septicaemia included HIV, tuberculosis and hepatitis serology; positive cocci and she was empirically commenced on glycated haemoglobin testing; vasculitic screening; a intravenous (IV) flucloxacillin 2 g four times a day and transthoracic echocardiogram; computed tomography of the vancomycin 1.5 g twice daily. chest, abdomen and pelvis to look for malignancy or abscesses; and a magnetic resonance imaging scan of her lumbosacral Shortly after admission, she revealed that she had been spine to exclude infection of the implants from her spinal fusion. experiencing 3 days of blurred vision and pain in her left eye. The results of these tests were unremarkable and no cause was Further history revealed that aside from mild myopia, her vision found to explain the S. pneumoniae septicaemia. was previously normal and she had never undergone any ophthalmic procedures. Her right eye was asymptomatic and Twelve days after admission, she was transferred to another appeared slightly injected but otherwise normal on initial centre with a vitreoretinal unit, where she underwent a left assessment (Figure, A). However, her left sclera was severely vitrectomy to debride the posterior chamber of her eye. injected, and the pupil was fixed and mildly dilated with corneal Unfortunately, the vision in her left eye only made a small and anterior chamber haze and a circumferential hypopyon recovery and, 6 months later, the VA was limited to counting (Figure, B). Visual acuity (VA) was 6/12 in her right eye, but only fingers. Fortunately, VA in her right eye remained at its baseline hand movements were appreciated in her left eye. Fundoscopy and she has been managing well in the community. u

Jeewaka E Mohotti MB BS(Hons)

Shuang Q Chan MB BS, BMedSc

Fumitaka Nonaka MB BS

Monash Health, Melbourne, VIC. The patient’s right eye (A) showing mild scleral injection but appearing otherwise unremarkable on initial assessment, and left eye (B) showing corneal haze, [email protected] circumferential hypopyon and injected left sclera. doi: 10.5694/mja15.00835

MJA 204 (2) j 1 February 2016 79 Case reports Lessons from practice

acterial endophthalmitis is an infection of the eye Difference between hypopyon in erect and supine patients B involving the aqueous and/or vitreous humour. It is an ophthalmic emergency and requires ur- gent treatment to prevent permanent blindness. The vast majority of cases are due to exogenous inoculation of microbes into the eye via trauma, surgery, intravitreal injections or an invasive corneal infection. Rarely, in 2e6% of cases, it can occur from haematogenous spread of organisms to the eye, which is referred to as endoge- nous or metastatic endophthalmitis. Endogenous spread is associated with immunosuppressive predisposing factors such as diabetes or malignancy in 90% of cases.2 Patients usually experience 12e24 hours of eye pain and decreasing vision. They are rarely systemically unwell. However, patients with the endogenous variant are usually unwell from the underlying bacteraemia. On ex- amination, there is often conjunctival injection or oedema of the cornea. VA will be decreased. Slit-lamp examin- ation of the anterior chamber may show cells and flare ceftazidime or amikacin. This is often combined with (small floating particles and a generalised haziness, vitrectomy, which debrides the vitreous, reducing the respectively, in the anterior chamber representing bacterial load. Patients should also be treated with inflammation). As in this patient, it may be also be asso- systemic antibiotics for sufficient duration to clear the ciated with a hypopyon. Hypopyon is pus in the anterior underlying infection.7 chamber of the eye which will collect inferiorly and form a Bilateral endogenous bacterial endophthalmitis is horizontal layer in an erect patient (Figure, B shows a very rare, with one study estimating that only around circumferential hypopyon in our patient as she was su- 12% of patients with endophthalmitis had both eyes pine at the time she was photographed; the Box highlights infected.2 A rare bilateral case like ours, where one eye is the difference between hypopyon in erect and supine severely infected and the other is in the early stages patients). On fundoscopy, there is usually poor visual- 2,3 of infection, serves to demonstrate the importance of isation of the retina secondary to vitreous haze. The early diagnosis, as once vision has been lost it is far less diagnosis can be confirmed via aqueous or vitreous cul- likely to return. Further, our case is unusual in that no ture, but it should be noted that history and examination immunosuppression was found in a relatively young are the main diagnostic tools, as a negative culture cannot 4 patient. reliably exclude the condition. Bacterial endophthalmitis is usually exogenous and postoperative. It is most commonly caused by coagulase- Lessons from practice negative staphylococci (the most common normal flora of  Endogenous bacterial endophthalmitis can rapidly cause the ocular surface).5 The organisms for the endogenous blindness and should be considered in all bacteraemic form depend on the underlying infection. A major study patients with decreased visual acuity or ocular pain.  showed only 30% of patients with streptococcal Risk factors include diabetes, malignancy and fi immunosuppression. endophthalmitis had a nal VA of 6/30 or better, which is  Staphylococcus aureus Early diagnosis is important as visual acuity on diagnosis is worse than for , gram-negative the strongest indicator of final visual prognosis. bacteria (50% for both) and coagulase-negative staph-  Early ophthalmology involvement and intravitreal antibiotic 6 ylococci (80%). Regardless of the organism involved, the injections are essential, as intravenous therapy alone will strongest indicator of visual prognosis is VA at not deliver adequate concentrations to the relatively presentation.5 avascular vitreous. u Treatment of endophthalmitis requires prompt referral to

an ophthalmology team. Treatment of bacterial endoph- Competing interests: No relevant disclosures. n thalmitis involves intravitreal antibiotic injections as the intravenous route does not deliver sufficient concentra- ª 2016 AMPCo Pty Ltd. Produced with Elsevier B.V. All rights reserved. tions to the relatively avascular posterior chamber of the eye. Empirical therapy is usually vancomycin with References are available online at www.mja.com.au.

80 MJA 204 (2) j 1 February 2016 Lessons from practice Case reports

1 Shorr AF, Zilberberg MD, Kan J, et al. Azithromycin and survival the endophthalmitis vitrectomy study. Arch Ophthalmol in Streptococcus pneumoniae pneumonia: a retrospective 1997; 115: 1142-1150. BMJ Open study. 2013; 3(6). 5 Gupta A, Orlans HO, Hornby SJ, Bowler IC. Microbiology and visual 2 Jackson TL, Eykyn SJ, Graham EM, Stanford MR. Endogenous outcomes of culture-positive bacterial endophthalmitis in Oxford, bacterial endophthalmitis: a 17-year prospective series and UK. Graefes Arch Clin Exp Ophthalmol 2014; 252: 1825-1830. Surv Ophthalmol review of 267 reported cases. 2003; 48: 6 Endophthalmitis Vitrectomy Study Group. Microbiologic factors 403-423. and visual outcome in the endophthalmitis vitrectomy study. 3 Shrader SK, Band JD, Lauter CB, Murphy P. The clinical Am J Ophthalmol 1996; 122: 830-846. spectrum of endophthalmitis: incidence, predisposing factors, 7 Endophthalmitis Vitrectomy Study Group. Results of the and features influencing outcome. J Infect Dis 1990; 162: Endophthalmitis Vitrectomy Study: a randomized trial of 115-120. immediate vitrectomy and of intravenous antibiotics for the 4 Barza M, Pavan PR, Doft BH, et al. Evaluation of treatment of postoperative bacterial endophthalmitis. Arch microbiological techniques in postoperative endophthalmitis in Ophthalmol 1995; 113: 1479-1496. n

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