[Atypical ocular toxoplasmosis with concomitant ocular reactivation of varicella-zoster virus and cytomegalovirus in an immunocompromised host].

Background: Necrotising retinopathy in immunocompromised hosts is characterised by an unfavourable course often with unspecific clinical features. Therefore, differential diagnosis can be critical.
History and Signs: A case of an initially therapy-resistant, necrotizing retinopathy is presented in a 65-year-old immunocompromised male patient suffering from chronic B-cell leukemia.
Therapy and Outcome: Despite demonstration of cytomegalovirus and Varicella-Zoster-Virus DNA by polymerase chain reaction in vitreous, aqueous humour samples and from retinal biopsy with specific antiviral therapy, a progression of retinal necrosis was noted. Finally Toxoplasma gondii DNA was detected and retinal necrosis resolved after specific treatment. However, visual acuity remains poor because of optic nerve atrophy.
Conclusions: The polymerase chain reaction is an important diagnostic tool for differential diagnosis in immunocompromised patients suffering from necrotising retinopathy. If resistance to therapy is noted atypical ocular toxoplasmosis should be considered. The presented case report shows that even multiple infections are possible in the same host.