AIDS-Associated BK Virus Nephropathy in Native Kidneys: A Case Report and Review of the Literature.

BK virus (BKV) is a small DNA virus, a member of the polyomavirus family, that causes an opportunistic infection in immunocompromised patients, especially kidney transplant patients. This virus establishes a lifelong infection in most of the population, and once it reactivates in an immunocompromised state, leads to BKV nephropathy. This review seeks to assess the correlation between severe immunosuppression, evident by low CD4 cell counts in HIV-positive patients, and the reactivation of BKV, causing nephropathy.

Relationship of Post-Transplant Lymphoproliferative Disorders (PTLD) Subtypes and Clinical Outcome in Pediatric Heart Transplant Recipients: A Retrospective Single Institutional Analysis/Experience of 558 Patients.

Post-transplant lymphoproliferative disorders (PTLD) are heterogenous lymphoproliferative disorders that develop as a consequence of immunosuppression in transplant recipients. We sought to determine if subtypes of PTLD correlated with different outcomes. We performed a retrospective review of PTLD occurring in pediatric heart transplant recipients.

Prenatal administration of heparin-binding epidermal growth factor-like growth factor in an experimental model of necrotizing enterocolitis decreased both incidence and severity of the disease.

Background: Necrotizing enterocolitis (NEC) is the leading gastrointestinal cause of death in premature infants and causes long-term disabilities. Previously, enteral heparin-binding epidermal growth factor-like growth factor (HB-EGF) administered after birth demonstrated decreased incidence and severity of NEC in a neonatal animal model of NEC. We investigated the potential prophylactic strategy of preventing NEC using prenatally administered HB-EGF.

Mast cell sarcoma: clinicopathologic and molecular analysis of 10 new cases and review of literature.

Mast cell sarcoma (MCS) is an exceedingly rare form of mastocytosis characterized by invasive malignant mast cell growth and metastatic potential. Diagnosis of MCS is very challenging due to its marked morphologic variations and significant immunophenotypic overlap with other neoplasms. In this study, we undertook an extensive study of 10 cases of MCS from our series, with review of additional 24 cases from the literature, to better clarify the clinicopathologic and molecular features of MCS.

Congenital Myenteric Hypoganglionosis.

Congenital myenteric hypoganglionosis is a rare developmental disorder characterized clinically by severe and persistent neonatal intestinal pseudoobstruction. The diagnosis is established by the prevalence of small myenteric ganglia composed of closely spaced ganglion cells with sparse surrounding neuropil. In practice, the diagnosis entails familiarity with the normal appearance of myenteric ganglia in young infants and the ability to confidently recognize significant deviations in ganglion size and morphology.

Severe chronic bowel obstruction associated with brown bowel syndrome.

A 61-year-old alcoholic male with history of cholecystectomy presented with a 20-year history of recurrent bowel obstruction and a 30 lb weight loss. After numerous attempts at conservative management, exploratory laparotomy was performed, which showed no mechanical cause. Despite no clear etiology, the obstruction persisted and intensified.

A case report of heart transplant for ischaemic cardiomyopathy from lupus coronary vasculitis.

Background: Coronary vasculitis is a rare, life-threatening complication of systemic lupus erythematosus (SLE).

Case Summary: A 23-year-old woman with SLE presented with typical angina and worsening dyspnoea on exertion. Coronary angiography revealed severe triple vessel disease with a 'string of beads' appearance classic for coronary vasculitis.

Regional Lymph Node Enlargement in Clinically Severe Cherubism.

Cherubism is a rare benign autosomal dominant disorder characterized by progressive, painless, bilateral enlargement of the mandible and/or maxilla because of bone replacement by fibrotic stromal cells and osteoclast-like cells forming multilocular cysts. The lesions typically stabilize and regress after puberty. We present a 14-year-old male with severe familial cherubism.

Short tau inversion recovery magnetic resonance imaging for staging and screening in myxoid liposarcoma.

Purpose: Myxoid liposarcoma has a propensity to metastasize to bone. MRI is the preferred modality for detecting bone disease. We evaluated multiple MRI sequences to determine an optimal screening method.

Spontaneous Regression of Diffuse Periosteal Melanotic Neuroectodermal Tumor of Infancy in the Tibia, With 13-Year Follow-up.

Melanotic neuroectodermal tumor of infancy (MNTI) is a rare entity primarily affecting the craniofacial bones during the first year of life, with only 5 reported cases involving peripheral long bones. We herein present a case of MNTI in the tibia of an infant, with a somewhat atypical presentation, and a noteworthy clinical course characterized by progressive spontaneous resolution without therapy, thus sparing the child the trauma of amputation. There is no evidence of active residual or recurrent disease with 13-year follow-up.

Undifferentiated embryonal sarcoma of the liver with an unusual presentation: case report and review of the literature.

Undifferentiated embryonal sarcoma of the liver (UESL) is a rare malignant mesenchymal neoplasm, relatively unique to the liver that occurs primarily in children and teenagers. Delay in diagnosis is not uncommon due to lack of a characteristic clinical presentation, serological markers and radiological changes. We report a case of UESL in a 9-year-old girl who presented with right upper quadrant pain and a palpable mass.

Cytotoxic Molecule-positive Epstein-Barr Virus-associated Peripheral T-cell Lymphoma in a 20-Month-old Child: A Case Report and Review of the Literature.

Peripheral T-cell lymphoma (PTCL) is rare in children. Expression of cytotoxic molecules (CM) in nodal PTCL has unique clinicopathologic features, including an Epstein-Barr virus (EBV) association. However, CM+, EBV-associated PTCL is extremely rare in the childhood, with only 1 study having been reported to date, including both pediatric and adult patients.

Mast cell sarcoma in an infant: a case report and review of the literature.

Mast cell diseases comprise a spectrum of disorders including cutaneous mastocytosis, indolent or aggressive systemic variants including leukemia, and unifocal tumor formations such as benign extracutaneous mastocytoma or aggressive mast cell sarcoma (MCS). Many mast cell diseases are associated with aberrancy of c-KIT proto-oncogene resulting in tyrosine kinase activity, typically exhibiting point mutation in codon 816. MCS is an exceedingly rare clinicopathologic entity characterized by a unifocal accumulation of neoplastic mast cells that grow in a locally destructive manner.

Cause of death in pediatric and infant heart transplant recipients: review of a 20-year, single-institution cohort.

Background: As infant and pediatric heart transplantation becomes more common, there is a growing need to better understand the causes of failure or death, if we are to continue to improve the outcome in these children.

Methods: A multidisciplinary team reviewed all deaths occurring in the cohort of infants and children transplanted during the first 20 years of the Loma Linda Pediatric Heart Transplant program, with 2 additional years of follow-up beyond the 20-year accrual period, and classified them as to cause.

Results: There were 169 deaths among 421 recipients, with a median follow-up of 9.

Complete absence of KSHV/HHV-8 in posttransplant lymphoproliferative disorders: an immunohistochemical and molecular study of 52 cases.

Posttransplant lymphoproliferative disorders (PTLDs), a heterogeneous group of monoclonal or polyclonal lesions, occur in immunosuppressed patients after solid organ or bone marrow transplantation. Although most PTLDs are Epstein-Barr virus (EBV)+ and seem to represent EBV-induced proliferations of monoclonal (or less often polyclonal) B, T, or plasma cells, a subset of PTLDs is EBV-. Because Kaposi sarcoma-associated herpesvirus/human herpesvirus 8 (KSHV/HHV-8) has been described in association with the development of hematolymphoid and nonhematolymphoid neoplasms in HIV+ patients, we investigated whether there is an association between KSHV/HHV-8 and PTLDs.

Frequent expression of CD99 in anaplastic large cell lymphoma: a clinicopathologic and immunohistochemical study of 160 cases.

Originally described as a diagnostically useful marker for Ewing sarcoma, CD99 immunoreactivity has also been documented in a variety of other tumors, including hematopoietic neoplasms. By using conventional paraffin immunoperoxidase staining and tissue microarrays, we retrospectively investigated CD99 expression in a series of 160 anaplastic large cell lymphoma (ALCL) cases. Of the 160 cases, 103 (64.

Comparison of a novel one-step percutaneous nephrolithotomy sheath with a standard two-step device.

Objectives: Percutaneous nephrolithotomy (PCNL) is the treatment of choice for large renal calculi. The most widely used access sheath for PCNL involves two steps including placement of a high-pressure balloon catheter (HPBC) followed by advancement of a sheath over the balloon. A novel PCNL balloon/sheath combination (NSS) has been developed that allows for both dilation and sheath placement in a single step.

Bioluminescent mammalian cells grown in sponge matrices to monitor immune rejection.

The growth and bioluminescence of cells seeded in collagen and gelatin sponge matrices were compared in vitro under different conditions, and immune rejection was quantified and visualized directly in situ based on loss of bioluminescence activity. Mammalian cells expressing a Renilla luciferase complementary deoxyribonucleic acid (cDNA) were used to seed collagen and gelatin sponge matrices soaked in either polylysine or gelatin to determine optimal growth conditions in vitro. The sponges were incubated in tissue culture plates for 3 weeks and received 2, 9, or 15 injections of coelenterazine.

High-density single nucleotide polymorphism array analysis in patients with germline deletions of 22q11.2 and malignant rhabdoid tumor.

Malignant rhabdoid tumors are highly aggressive neoplasms found primarily in infants and young children. The majority of rhabdoid tumors arise as a result of homozygous inactivating deletions or mutations of the INI1 gene located in chromosome band 22q11.2.

Undifferentiated embryonal sarcoma of the liver successfully treated with chemotherapy and liver resection.

Undifferentiated embryonal sarcoma is the third most common malignant tumor of the liver in children, accounting for 13% of hepatic malignancies in this age group. It has been considered an aggressive neoplasm with very poor prognosis until the late 1980s, when long-term survivors were reported after multiagent chemotherapy followed by resection. We, herein, report two pediatric cases of undifferentiated embryonal sarcoma treated successfully with surgical resection after neoadjuvant chemotherapy based on therapy used in childhood soft tissue sarcomas and in childhood hepatic malignancies.

Postmortem intracranial neuropathology in children following cardiac transplantation.

At Loma Linda University Children's Hospital, the medical information of 405 pediatric patients who received orthotopic cardiac transplantation were reviewed. Of those who died (n=136), 86% (n=117) underwent postmortem examinations, and the brain was examined in 61% (n=82, male=39). The number and type of intracranial lesions present were compiled, and these were matched to underlying functional cardiac disease categories.

Hodgkin lymphoma-like posttransplant lymphoproliferative disorder (HL-like PTLD) simulates monomorphic B-cell PTLD both clinically and pathologically.

Although Hodgkin lymphoma-like posttransplantation lymphoproliferative disorder (HL-like PTLD) has been grouped with classic Hodgkin lymphoma type PTLD (HL-PTLD), controversy remains as to whether it is truly a form of HL or whether it should be more appropriately classified as a form of B-cell PTLD. Because only few cases of HL-like PTLD have been reported, their pathologic nature and clinical behavior have not been well defined. This report characterized 5 cases of HL-like PTLD with respect to their immunophenotype, EBV status, clonality, and clinical outcome.