Pancreatic lymphoepithelial cyst with concurrent HIV infection: A case report and review of the literature.

Pancreatic lymphoepithelial cysts are rare, benign, non-neoplastic unilocular or multilocular cystic lesions. These circumscribed pancreatic lesions are filled with keratinous material grossly and exhibit distinct microscopic features. Pancreatic lymphoepithelial cysts are like the more common lymphoepithelial cysts of the parotid glands, which have been associated with the diffuse infiltrative lymphocytosis syndrome often seen in patients with HIV infection. However, pancreatic lymphoepithelial cysts are rare and their association with HIV infection has not been established. The presence of secondary changes in non-neoplastic cysts such as goblet cell metaplasia that was present in our case is an important feature to be included in the differential diagnosis and not to be interpreted as a mucinous neoplasm, particularly on fine-needle aspiration specimen microscopic evaluation that would impact further management. Here we describe the diagnosis and treatment of lymphoepithelial cysts in a patient who was on highly active antiretroviral therapy for HIV infection and we provide a brief literature review. Defining the clinical characteristics of lymphoepithelial cysts in patients with HIV and determining accurate preoperative diagnostic procedures will be critical for establishing effective surgical and medical approaches to treating these cysts, which differ substantially from other more serious pancreatic cystic lesions.

Complete Neurologic Recovery of Cerebral Fat Embolism Syndrome in Sickle Cell Disease.

Sickle cell disease is one of the most common inherited hemoglobinopathies diagnosed in the United States. Patients often present with severe anemia, pain crises, infections, and vaso-occlusive phenomena. Complications of these disorders can lead to significant debilitating morbidity and mortality. Fat embolism syndrome (FES) is a rare and devastating complication of sickle cell disease. It usually presents with a rapidly deteriorating clinical course, and the prognosis is dismal. We report a case of FES in a 19-year-old African American male with a history of sickle cell disease who presented with tonic-clonic seizures and was found to have multi-organ failure. FES was diagnosed 20 days from a presentation based on blood cytopenias and magnetic resonance imaging findings that were obscured at the initial presentation. We describe in this report, the patient's course from presentation until diagnosis and resolution. Our case is peculiar as the patient had a very good outcome without the need for red blood cell (RBC) exchange; instead, supportive treatment and simple RBC transfusions were enough to change the clinical course of this almost fatal syndrome.

Thrombocytapheresis for acquired von Willebrand syndrome in a patient with essential thrombocythemia and recent multivisceral transplantation.

BACKGROUND: Essential thrombocythemia (ET) is associated with increased risk of bleeding secondary to acquired von Willebrand syndrome (AVWS). Bleeding in ET requires urgent platelet reduction by cytoreductive therapy such as hydroxyurea or thrombocytapheresis. We report on the efficacy and safety of thrombocytapheresis in managing AVWS in a patient with ET and multivisceral transplantation. CASE REPORT: The patient was a 51-year-old female who underwent multivisceral transplantation. Her postoperative course was complicated by bleeding from oral cavity, IV lines, gastrointestinal and upper respiratory tracts as well as vaginal bleeding, which coincided with ET flare with a platelet count of 1512 × 109 /L. Coagulation studies including von Willebrand factor (vWF) antigen and activity, vWF propeptide antigen, and vWF multimer analysis were consistent with AVWS. Hydroxyurea was initiated. However, due to major bleeding, rapidly increasing platelet count, and uncertainty of response to hydroxyurea being given through the enteral tube, thrombocytapheresis was initiated for rapid platelet reduction. The patient tolerated the procedure well. Platelet count was reduced from 1636 × 109 /L to 275 × 109 /L with rapid cessation of bleeding. The patient's condition stabilized over the next few days; however, bleeding recurred with increasing platelet count, which required a second thrombocytapheresis 8 days after the first one. The patient was maintained on hydroxyurea 500 mg twice/day. At 11-month follow-up, she had a normal platelet count and no recurrence of bleeding. DISCUSSION: Thrombocytapheresis is safe and efficient in managing postoperative bleeding due to ET/AVWS in solid organ transplant patients. The procedure can be an adjunct to bridging therapy before response to hydroxyurea is achieved.

Telomere and ATM Dynamics in CD4 T-Cell Depletion in Active and Virus-Suppressed HIV Infections.

CD4 T-cell depletion is a hallmark of HIV/AIDS, but the underlying mechanism is still unclear. We have recently shown that ataxia-telangiectasia-mutated (ATM) deficiency in CD4 T cells accelerates DNA damage, telomere erosion, and cell apoptosis in HIV-infected individuals on antiretroviral therapy (ART). Whether these alterations in ART-treated HIV subjects occur in vitro in HIV-infected CD4 T cells remains unknown. In this study, we employed a cellular model of HIV infection to characterize the mechanisms underlying CD4 T-cell destruction by analyzing the telomeric DNA damage response (DDR) and cellular apoptosis in highly permissive SupT1 cells, followed by the validation of our observations in primary CD4 T cells with active or drug-suppressed HIV infection. Specifically, we established an in vitro HIV T-cell culture system with viral replication and raltegravir (RAL; an integrase inhibitor) suppression, mimicking active and ART-controlled HIV infection in vivo We demonstrated that HIV-induced, telomeric DDR plays a pivotal role in triggering telomere erosion, premature T-cell aging, and CD4 T-cell apoptosis or depletion via dysregulation of the PI3K/ATM pathways. This in vitro model provides a new tool to investigate HIV pathogenesis, and our results shed new light on the molecular mechanisms of telomeric DDR and CD4 T-cell homeostasis during HIV infection.IMPORTANCE The hallmark of HIV infection is a gradual depletion of CD4 T cells, with a progressive decline of host immunity. How CD4 T cells are depleted in individuals with active and virus-suppressed HIV infection remains unclear. In this study, we employed a cellular model of HIV infection to characterize the mechanisms underlying CD4 T-cell destruction by analyzing the chromosome end (telomere) DNA damage response (DDR) and cellular apoptosis in a T-cell line (highly permissive SupT1 cells), as well as in primary CD4 T cells with active or drug-suppressed HIV infection. We demonstrated that HIV-induced telomeric DDR plays a critical role in inducing telomere loss, premature cell aging, and CD4 T-cell apoptosis or depletion via dysregulation of the PI3K/ATM pathways. This study sheds new light on the molecular mechanisms of telomeric DDR and its role in CD4 T-cell homeostasis during HIV infection.