Post-Transplant Lymphoproliferative Disorder: A Rare Case of CNS Involvement following Renal Transplant.

BACKGROUND: Post-transplant lymphoproliferative disorders (PTLD) are rare immunosuppression complications affecting 5% of transplant patients. Isolated central nervous system (CNS)-PTLD without nodal or extra-nodal organ involvement is rarely reported and is difficult to diagnose due to the non-specific clinical manifestations and imaging features overlapping with other common CNS lesions. CASE PRESENTATION: We present a case of a 72-year-old female subjected to a renal transplant 11 years ago with progressively worsening headaches and confusion. Imaging revealed vasogenic edema in the left frontal and bilateral temporal lobes. She was subjected to a craniotomy and excisional biopsy to obtain tissue for diagnostic and therapeutic interventions. Pathology examination showed atypical EBV-positive lymphoplasmacytic infiltrate, consistent with Polymorphic type PTLD. CONCLUSIONS: Patients diagnosed with PTLD need to have close monitoring of immunosuppressive medications while in the hospital. Early diagnosis is essential for patient survival with PTLD, as their health can deteriorate fast.

Paradoxical Distraction with Upright Position After Halo Fixation in 2 Patients with Atlanto-Occipital Dislocation.

BACKGROUND: Atlanto-occipital dislocation (AOD) is the most uncommon form of traumatic cervical spine injury. The majority of patients die before reaching higher-level care, and only a small percentage of patients with AOD survive the initial injury after receiving tertiary care. As such, there is a paucity of evidence-based management guidelines for treating this condition. Halo vest fixation has been a proposed method for interim stability while these patients undergo medical optimization for surgical intervention. There have been several reports of worsening AOD after halo placement. Reverse Trendelenburg position after halo fixation has been previously described to aid in the reduction of AOD, as well as concomitant atlantoaxial dislocation by gravitational downward force. CASE DESCRIPTION: In this series we present 2 cases of obese patients (body mass index >30) with AOD treated by halo fixation that had increased distraction after head of bed elevation. CONCLUSION: Our theorized mechanism for this phenomenon is due to the downward pull of subaxial forces secondary to a large body habitus.