| Affiliation |
(AGL) Chairman, Department of Ophthalmology, The Methodist Hospital, Houston, Texas; Professor of Ophthalmology, Weill Cornell Medicine, New York City, New York; (HK) Class of 2023, Baylor College of Medicine, Houston, Texas |
| Transcript |
So today I'm going to tell you about patients who have had some sort of transplant and are immunosuppressed. It could be lung transplant, heart transplant, renal transplant, they all kind of have the same flavor. They've all had some sort of organ transplant, and that means they're on chronic immunosuppression. And so what that means to you in neuro-op is it can be from the disease, it can be from the treatment of the disease, or it can be a side effect of the treatment of the disease. And the side effect we worry about in immunosuppression is infectious side effects. So normally when we're doing the differential, we're thinking about single entities. But when you have transplant and immunosuppression you really have to be thinking about infectious versus non-infectious etiologies and we have to be thinking about ischemia because the patients often have anemia or they might have other vasculopathic risk factors that are unrelated to their immunosuppression but are related to the surgery that they had for the transplant. And we have to be thinking about neoplastic etiologies because the immune system is not only in charge of killing bugs, it's in charge of killing cancer, and if you have a transplant, you might have post-transplant lymphoproliferative disorder, which is lymphoma usually, but it doesn't have to be. So, in neuro-op both on the afferent and the efferent side we're going to be thinking about infectious, non-infectious, ischemic, and neoplastic conditions in immunosuppression. So we can construct the stem, the stem will be replicated throughout and we'll just use that stem to drive the differential diagnosis. So a 55 year old white male has had a bilateral lung transplant, he's on chronic immunosuppression therapy with tacrolimus or CellCept or whatever they're on and steroids. So one of the things we would be worried about in the infectious categories are going to be CMV and other opportunistic infections. So CMV retinitis, herpes simplex retinitis, herpes zoster, all can present to us with vision loss on the afferent sides as retinitis. So when we have a retinitis or an optic neuritis in an immunosuppressed person the infections we are thinking about are the opportunistic infections: tuberculosis, herpes, CMV. And the same would go, by the way, if the patient was HIV, just take away the transplant, it would be the same. The non-infectious things that we have to worry about include ischemia after the trauma, either from the blood loss, or hypotension, or the anesthesia. And so that's going to be ischemic optic neuropathy, central retinal artery occlusion, central retinal vein occlusions, ocular ischemic syndrome, ophthalmic artery occlusion, all of these are in the differential because you had a surgical procedure and usually a transplant is a big surgery: it is long duration, they often have blood loss, they have anemia pre- and post-operatively, and the positioning of the patient might also be at play in terms of venous return. And then finally we are going to be thinking about neoplastic conditions, and the neoplasm that you have to worry about is post-transplant lymphoproliferative disorder. And the reason that is a problem is because immunosuppression allows EBV to proliferate, and EBV as you know is an oncogene that activates the replication of lymphocytes and so there's EBV related lymphoproliferative disorders, the prototype, Burkitt's lymphoma. But a lot of the lymphomas, diffuse large B cell lymphoma, and especially post-transplant lymphoproliferative disorder, are EBV driven because of the immunosuppression. And in the conjunctiva and on the skin you have to worry about squamous cell carcinoma. So in summary, transplant patients you've got to worry about the disease, direct ischemic events related to blood loss, ischemic events, or hypotension related to the surgery itself. You have to worry about the treatment of the disease, the immunosuppressive agents, tacrolimus, steroids, they have side effects. For steroids, that is cataract and glaucoma. For tacrolimus and cyclosporine, that's posterior reversible encephalopathy syndrome (PRES), its pseudotumor cerebri. Those are side effects of the treatment of the disease, not the disease itself. You also need to worry about infections released by the immunosuppression. CMV, herpes, herpes simplex, herpes zoster, toxoplasmosis, tuberculosis, any kind of infection can be unleashed. And if EBV is unleashed, the EBV related lymphomas: post-transplant lymphoproliferative disorders. |
