Statistics from Altmetric.com
Rhodotorula species are imperfect basidiomycetous yeasts belonging to the family Cryptococcaceae and are widespread throughout nature.1 In many clinical situations Rhodotorula spp are considered a contaminant, but when identified in normally sterile sources such as blood, cerebrospinal fluid and vitreous the cultures are significant for mycotic infection.1 Human disease is extremely rare with Rhodotorula spp but opportunistic cases of endocarditis, septicaemia, meningitis, ventriculitis, and peritonitis are reported in the literature.2 Ocular infections include chronic dacryocystitis,3 keratitis,4 chronic postoperative endophthalmitis,5 and corneal lamellar graft infection.6 It is becoming increasingly important to clinically recognise and consider such opportunistic organisms as an increasing number of patients are immunocompromised by either iatrogenic or disease related causes. Immunocompromised status, indwelling catheters, recent surgery of trauma, and injecting drug use appear to be the major factors leading to infection.1,7,8 This report presents a case of endogenous Rhodotorula rubra infection in an HIV positive male.
A 26 year old man was referred to the Ottawa Eye Institute by the infectious disease department with a 6 week history of floaters and a 2 week history of minor pain, tearing, injection, and decreasing vision in the right eye. Vision had declined to hand movements 1 week before examination. He was systemically asymptomatic, afebrile, and had no localising symptoms.
Past medical history was significant for injecting drug use, a diagnosis of HIV with concomitant lung abscess in 1991, and osteomyelitis of the L3 vertebrae in 1999. He had no previous ocular history. He was taking 95 mg of methadone daily and denied use of antiretroviral medications. He has an 11 pack year smoking history and denied alcohol use.
Review of systems disclosed multiple track marks on both arms, but was otherwise unremarkable. Best corrected visual acuity was hand movements in the right eye and 20/20 in the left eye. Four plus cells were present in the anterior chamber and vitreous cavity of the right eye. Multiple superficial creamy retinal, vitreous, and anterior chamber infiltrates were present. He was admitted to hospital and started on intravenous amphotericin B 1 mg/kg daily. Vitreous cultures, blood cultures, urine cultures, and a chest x ray was performed.
No improvement was appreciated 2 days after presentation and intravitreal injection of amphotericin B, vancomycin, and tobramycin was performed. The patient refused vitrectomy at this time. Blood cultures, urine cultures, and chest x ray were normal. The patient was discharged home with close monitoring. He was partially compliant with a homatropine and steroid eye drop regimen. Cultures of the vitreous aspirate grew Rhodotorula rubra on the fifth day after culture and the specimen was sent to the provincial laboratory for confirmation. The patient showed no improvement clinically. An intravitreal injection of amphotericin B was repeated. Examination at this time disclosed significant posterior synechiae, iris bombe, and numerous vitreous cells adherent to the posterior lens capsule. No view of the fundus was possible. A B-scan disclosed an open funnel retinal detachment. A vitrectomy was offered with guarded prognosis. The patient now accepted this procedure. Following vitrectomy the vision became no light perception and a total non-repairable retinal detachment was present. Provincial laboratory results confirmed infection with Rhodotorula rubra. Enucleation was offered because of concern about dissemination of fungus systemically.
Endogenous endophthalmitis accounts for 2–15% of all endophthalmitis cases and fungi account for over half of all cases.9 Fungaemia leads to metastatic seeding of organisms in the choroid and subsequent intraocular infection, although in many cases the patient is systemically asymptomatic and blood cultures may be negative. Bilateral involvement is present in 25% of cases.9 Despite current antibiotic therapy and surgical advances the prognosis for patients with endogenous endophthalmitis remains disappointing because of factors such as organism virulence, compromised host status, and delay in diagnosis.10 The best treatment regimen is unresolved with reports of amphotericin B, 5-fluorocytosine, and a combination of both medications1 with or without vitrectomy. Despite aggressive medical and surgical management our patient was eventually offered enucleation as the eye had no light perception and was a possible nidus for infection. Future investigations into prevention, optimal diagnostic techniques, and appropriate management are needed.