Nocardia veterana endogenous endophthalmitis in a cardiac transplant patient

Abstract

BackgroundEndogenous endophthalmitis secondary to Nocardia species is extremely rare but often portends a poor visual prognosis often owing to the advanced nature of disease at presentation and delay in diagnosis. Patients who are systemically immunosuppressed are at greatest risk and early suspicion of the role of this organism in patients with acute panuveitis is paramount.FindingsA 66-year-old cardiac transplant patient on oral prednisone, Myfortic, and tacrolimus developed unilateral panuveitis with a focal white subretinal and retinal lesion. His past medical history was notable for Aspergillus pneumonia and cytomegalovirus retinitis in the contralateral eye 12 months prior. Aqueous humor sampling for eubacterial, eufungal, and viral PCR testing, as well as vitreous cultures for bacteria and fungi were unsuccessful in the identification of a causative organism. Progressive enlargement of the lesion was noted despite intravitreal foscarnet, vancomycin, ceftazidime, and voriconazole. A pars plana vitrectomy and retinal and subretinal biopsy led to the identification of Nocardia veterana, a recently identified Nocardia species. A combination of linezolid, meropenem, azithromycin, ceftriaxone, and intravitreal amikacin resulted in eradication of the infection.ConclusionThis is the first reported case of N. veterana endogenous endophthalmitis in an immunosuppressed patient. Pars plana vitrectomy with a subretinal biopsy was required to establish a diagnosis, as other testing including aqueous PCR and vitreous cultures were negative. The poor visual outcome in our patient highlights the importance of early consideration of Nocardia in the differential diagnosis of panuveitis with subretinal disease in the context of immunosuppression.

The successful treatment of a multidrug-resistantAchromobacter xylosoxidanscorneal ulcer with topical meropenem

“…It has approved use by the Food and Drug Administration (FDA) for the treatment of skin and gastrointestinal infections, as well as for bacterial meningitis 10. Its intravitreal use in the treatment of endophthalmitis resistant to other antibiotic agents has also been reported 11. There has been a report of its topical use in successfully treating cases of pseudomonal keratitis 12.…”

Diagnostic Vitrectomy for Infectious Uveitis

“…45, 46 Nocardia species may cause either exogenous infections (usually keratitis, scleritis, and post-surgical endophthalmitis) in patients with exposure to agriculture 47, 48 or endogenous ocular Nocardiosis (EON) from hematogenous spread in immunocompromised individuals (Figure 3). 49 …”

“…50 In 5 cases, 6 vitreous taps were pursued 46, 52–55 of which 4 were non-diagnostic by either microscopic analysis or culture. 46, 52, 54, 55 Pars plana vitrectomy led to identification of Nocardia species by staining and/or culture in 8 of 9 cases.…”

“…50 In 5 cases, 6 vitreous taps were pursued 46, 52–55 of which 4 were non-diagnostic by either microscopic analysis or culture. 46, 52, 54, 55 Pars plana vitrectomy led to identification of Nocardia species by staining and/or culture in 8 of 9 cases. 46, 54, 56–61 All cases underwent vitrectomy including retinal biopsy except for two cases 58, 62 of which 1 was non-diagnostic by vitreous fluid analysis.…”

Pharmacokinetics of Meropenem for Use in Bacterial Keratitis

“…11 There are also a small number of case reports supporting the safe use of intravitreal meropenem to treat endophthalmitis resistant to other antimicrobials. [12][13][14] To our knowledge, however, there are no reports of the ocular pharmacokinetics of topically applied meropenem. This study investigates the in vitro toxicity and pharmacokinetics across the cornea of meropenem following topical delivery.…”