Pediatric Right Ventricular Cardiac Steatosis following Immunosuppressive Treatment.

Background Right ventricular myocardial fatty infiltration has been observed in pediatric cardiac allografts with an associated decrease in graft life expectancy. A possible explanation included an immunosuppressant drug effect which prompted us to examine common factors between non-cardiac transplanted immunosuppressed patients and postmortem hearts of pediatric patients who died of non-cardiac causes.Materials and Methods Sixty-one of 1,030 pediatric autopsies were from immunosuppressed children who were treated with corticosteroids for malignant tumors, non-cardiac transplantations, or other chronic clinical conditions. 62 children who died for non-medical reasons served as controls. Cardiac H&E autopsy slides were examined for right ventricular fatty infiltration.Results There was a significant increase in right ventricular fatty infiltration in patients that were non-cardiac transplanted and immunosuppressed compared to controls. None of the index patients had other features of arrhythmogenic right ventricular dysplasia.Conclusions Immunosuppression may lead to right ventricular fatty infiltration in childhood.

Paracrine Effects of Leydig Cell Nodular Hyperplasia, Two Case Reports: A Neglected Phenomenon.

Leydig cell nodular hyperplasia (LCNH) is a lesion that is less characterized than the familiar Leydig cell tumors. The paracrine effects of these lesions on adjacent gonadal stroma have not been widely documented. We present two cases of precocious puberty in pre-pubertal boys found to have a single LCNH with adjacent focal maturation of the seminiferous tubules. Blood tests showed elevated serum testosterone and dehydroepiandrosterone (DHEAS). Ultrasound revealed unilateral testicular enlargement with irregular echogenicity. Radical orchiectomy was performed. Histologically Leydig cell nodular proliferation without destruction of surrounding tubules was seen. Mature seminiferous tubules undergoing spermatogenesis were noted adjacent to the lesion, while away from the lesion seminiferous tubules were as expected in pre-pubescent boys. These cases emphasize the potential presence of both paracrine and endocrine effects in Leydig cell nodular hyperplasia. However, instances of the endocrine effects of hyperplastic Leydig cell lesions are more widely reported than the paracrine effects.

Suppurative Granulomatous Cholecystitis in a Pediatric Chronic Carrier with Salmonella enterica serotype Typhi: A Case Report and Review of Literature.

Bacterial infection of Salmonella enterica serotype Typhi is rare in the United States but endemic in many developing countries. Approximately 3-5% of patients become chronic asymptomatic carriers. We describe an atypical presentation of S. enterica serotype Typhi infection in a 10-year-old male, whose cholecystechtomy and bile culture revealed chronic carrier status despite negative stool tests and the absence of gallstones. The gallbladder showed marked thickening of the wall with an intense suppurative granulomatous reaction.

Contrast-Based Real-Time Assessment of Microcirculatory Changes in a Fatty Liver After Ischemia Reperfusion Injury.

OBJECTIVES: A fatty liver is known to have impairment of microcirculation, which is worsened after ischemia reperfusion injury (IRI). This makes most fatty grafts unsuitable for transplantation, and in the absence of real time assessment of microcirculation this selection has been at best, random. The aim of this study was to demonstrate the utility of a contrast enhanced ultrasound model in quantitative assessment of the microcirculation of a fatty liver. METHODS: We subjected fatty mice to IRI, and blood flow dynamics were assessed before and after the injury. RESULTS: There was a significant increase in the resistive and pulsatility index of the extrahepatic artery and a significant decrease in velocity of the portal vein. There was also a quantifiable decrease in the intrahepatic blood volume, blood flow, time to peak flow, and perfusion index of mice with fatty liver, suggesting that a fatty liver develops hemodynamic abnormalities after IRI, leading to increased hepatocellular injury. CONCLUSIONS: Hemodynamic abnormalities in liver can be reliably quantified using a contrast, enhanced Doppler ultrasound, which is an inexpensive technique with multiple clinical applications. It can be used to assess the quality of the fatty liver donor graft before organ retrieval; for determining live donor candidacy, for making post-IRI recovery prognosis, and for assessing the effectiveness of therapeutic interventions.

Identification of Bile Duct Paucity in Alagille Syndrome: Using CK7 and EMA Immunohistochemistry as a Reliable Panel for Accurate Diagnosis.

Bile duct paucity is the absence or marked reduction in the number of interlobular bile ducts (ILBD) within portal tracts. Its syndromic variant, Alagille syndrome (ALGS), is a multisystem disorder with effects on the liver, cardiovascular system, skeleton, face, and eyes. It is inherited as an autosomal dominant trait due to defects in NOTCH signaling pathway. ALGS is characterized by vanishing ILBD with subsequent chronic obstructive cholestasis in approximately 89% of cases. Cholestasis stimulates formation of new bile ductules through a process of neoductular reaction, making it difficult to evaluate the presence or absence of ILBD. Therefore, finding a method to differentiate clearly between ILBD and the ductular proliferation is essential for accurate diagnosis. A database search identified 28 patients with confirmed diagnosis of ALGS between 1992 and 2014. Additionally, 7 controls were used. A panel of two immunostains, cytokeratin 7 (CK7) and epithelial membrane antigen (EMA), was performed. CK7 highlighted the bile duct epithelium of ILBD and ductular proliferation, while EMA stained only the brush border of ILBD. In our ALGS group, the ratio of EMA-positive ILBD to identified portal tracts was 12.6% (range, 0%-41%). However, this same ratio was 95.0% (range, 90%-100%) among control cases (P < 0.001). We propose a panel of two immunostains, CK7 and EMA, to differentiate ILBD from ductular proliferation in patients with cholestasis. With this panel, identification of bile duct paucity can be achieved. Additional studies, including molecular confirmation and clinical correlation, would provide a definitive diagnosis of ALGS.

Giovanni Battista Morgagni (1682-1771), the First Pediatric Pathologist.

During the age of enlightenment in the 18th century, radical changes were occurring in the Western world in science, medicine, philosophy, religion, and socio-economic concepts. In medicine, major advances had already been underway since the days of Vesalius.

Thoracoschisis: A Case Report and Review of Literature.

Thoracoschisis is an extremely rare congenital birth defect in which intra-abdominal organs eviscerate through a defect in the thoracic wall(1). There are only seven previously reported pediatric cases and in each case, there is some diaphragmatic anomaly, suggesting that the defect took place before complete formation of the diaphragm. Our patient was referred to us from a local hospital immediately after delivery. The patient was born with a thoracoschisis of the left side below the 8(th) intercostal space. The thoracoschisis was repaired. Although there is a high prevalence of cardiac defects among thoracoschisis patients, this patient shows only small atrial septal defects.

Does MAP2 have a role in predicting the development of anti-NMDAR encephalitis associated with benign ovarian teratoma? A report of six new pediatric cases.

Anti-N-methyl-d-aspartate receptor (anti-NMDAR) encephalitis is a potentially fatal neurologic syndrome in which patients present with a spectrum of central nervous system deficits. Sixty percent of the cases can be attributed to the presence of tumors, most often ovarian teratomas. This report examines 6 pediatric patients who presented with neurologic deficits associated with the presence of such tumors. These cases illustrate a perplexing phenomenon, where benign teratomas could have a possible association with anti-NMDAR encephalitis. The purpose of this study was to compare the histology and immunohistochemistry of tumors associated with this syndrome to ovarian teratomas found in patients presenting with no neurologic symptoms. After obtaining institutional review board approval, 57 cases of ovarian teratomas were identified at our institution over 12 years. Six patients were identified with anti-NMDAR encephalitis. A panel of immunostains, including S100, GFAP, MAP2, and NeuN was applied to patients' tumor sections as well as the 6 controls from age-matched patients. No qualitative histologic or immunohistochemical differences were seen between the study cases and control group. Because no qualitative differences were identified between the study cases and the control group, testing of paired serum and cerebrospinal fluid remains the best method for diagnosis of anti-NMDAR encephalitis. Tumor banking with molecular analysis of ovarian teratomas, including whole-genome sequencing and comparative genomic hybridization between ovarian tissue saved from patients with and without anti-NMDAR encephalitis, is necessary to fully understand the etiopathogenesis of anti-NMDAR encephalitis.

Malakoplakia and primary immunodeficiency.

Malakoplakia, a rare granulomatous disease caused by impaired macrophage response, has been reported only rarely in children. We report 3 unique cases, with lesions occurring in unusual locations in children with primary immune deficiencies.

Correlating pathology with the clinical symptoms of methotrexate-induced leukoencephalopathy in a child with relapsed T-cell acute lymphoblastic leukemia.

Intrathecal and systemic methotrexate (MTX), as well as cranial radiation, are effective modalities to prevent central nervous system relapse in childhood acute lymphoblastic leukemia. Leukoencephalopathy is a well-described adverse effect of MTX therapy and is associated with a wide range of neurological sequelae. Most recent studies of MTX-induced leukoencephalopathy have focused exclusively on imaging findings, particularly magnetic resonance imaging. Here we report a case of severe MTX-induced leukoencephalopathy with unique magnetic resonance imaging findings and pathologic correlation from a brain biopsy taken during a period of active neurological symptomatology.

Noniatrogenic neonatal gastric perforation: the role of interstitial cells of Cajal.

Noniatrogenic neonatal gastric perforation is a rare and life-threatening condition whose etiology is often unclear. Interstitial cells of Cajal act as gastrointestinal pacemaker cells and express the proto-oncogene c-Kit. Six new cases were identified at our institution which presented with no mechanical, pharmacologic, or otherwise medical-related intervention prior to rupture. The number of interstitial cells of Cajal in nonnecrotic muscularis propria from five random high-power fields per specimen was compared using immunohistochemical stains for c-Kit. The authors show that a lack of interstitial cells of Cajal in the stomach musculature may be implicated in the development of noniatrogenic gastric perforation (p = 0.008). Further large-scale studies, including molecular and genetic analysis, may help to better understand this phenomenon.

Pathogenic Yersinia DNA in intestinal specimens of pediatric patients with Crohn's disease.

Studies indicate a close relationship between Yersinia and Crohn's disease in adults. Our study tested 77 colonic specimens from children with Crohn's disease for the presence of Yersinia DNA using a validated polymerase chain reaction (PCR) assay. Control cases included specimens from 45 ulcerative colitis patients and 10 appendicitis patients. The presence of Yersinia in Crohn's specimens was significant compared to the control specimens (9% vs. 0%; p = 0.0055). While our study supports the medical literature, future studies are needed to determine if the relationship between Crohn's disease and Yersinia is an initiating or mediating factor in the pathogenesis of pediatric Crohn's disease.

Epstein-Barr virus associated smooth muscle tumors in post transplant pediatric patients two cases of rare locations, and review of the literature.

Epstein-Barr virus (EBV) may present few or no symptoms in immunocompetent individuals; however, in immunocompromised patients as in the case of AIDS and post-transplant patients, the virus occasionally stimulates neoplastic transformations. Epstein-Barr virus may play a role in the development of smooth muscle tumors (SMT). In the case of Epstein-Barr associated smooth muscle tumors (EBV+SMT), the virus is thought to be the leading factor to the tumorigenic pathway. We report two pediatric patients (6 and 13 years old) who underwent liver transplantation and developed EBV+SMT in the colon and orbit. These two cases represent rare locations for this kind of lesion.

Usefulness of OCT4/3 immunostain in pediatric malignant germ cell tumors.

Octamer4/3 is a POU transcription factor that regulates pluripotentiality in embryonic stem and germ cells and primordial germ cells. When expressed in post-embryonic life, Octamer4/3 may lead to malignant germ cell tumors (GCT). Thirty samples were selected for this study (26 GCT samples and 4 cryptorchid testes samples) and 16 non-GCT were used as controls. Samples were stained with an anti-Octamer4/3 antibody. All cases of GCT were positive for Octamer4/3, and the non-GCT were negative. This article focuses on pediatric populations where we found that Octamer4/3 immunostaining is a useful diagnostic tool in undifferentiated pediatric tumors.

Clinico-pathologic findings in children with hepatopulmonary syndrome.

Hepatopulmonary syndrome (HPS) is infrequently reported in children. Clinical-pathological findings in 10 HPS children were compared with non-HPS controls. Six patients had cirrhosis and four had noncirrhotic portal hypertension (NCPH) 40%. Polysplenia and abnormal venous malformations were exclusive to this group. This prevalence of NCPH with systemic venous anomalies suggests that HPS is associated with pulmonary vasoactive factors not cleared by the liver. Hepatopulmonary syndrome should be considered in any patient with hypoxemia and intrapulmonary shunting whether there is overt clinical liver disease or not.

Clinical utility of DNA amplification and sequencing to identify a strain of Mycobacterium avium in paraffin-embedded, formalin-fixed biopsies from an immunosuppressed child.

Nontuberculous mycobacterial (NTM) infections are serious, though rare, in patients with severe combined immunodeficiency who have received bone marrow transplants. A 5-year-old female patient underwent stem cell/bone marrow transplant with disseminated NTM. Real-time polymerase chain reaction (PCR) using a fluorescence resonance energy transfer (FRET) probe for detection and identification of NTM was performed. The FRET-based real-time PCR assay amplified mycobacterial DNA, and the postamplification melt curve analysis classified the organism as a NTM. The pyrosequence of the hypervariable region A definitively identified the infecting organism as Mycobacterium avium. Real-time PCR along with melt curve analysis and pyrosequencing provides faster, definitive identification of mycobacteria, as compared to bacterial culture. In this case report, we emphasize the importance of utilizing molecular means for fast and accurate diagnosis.

Hepatic pulmonary fusion: two cases with diaphragmatic hernia and one case with Pentalogy of Cantrell.

Hepatic pulmonary fusion (HPF) is characterized by a fibrous connection between the liver and lung tissue. We present two cases of hepatic pulmonary fusion diagnosed with right diaphragmatic hernia and a third case with Pentalogy of Cantrell exhibiting complete agenesis of the diaphragm and finger-like projections of liver adhered to the right lung. It has been proposed that this anomaly is secondary to developmental failure of the mesoderm between days 14-18 after conception and is attributed to diaphragmatic maldevelopment. Understanding the molecular-genetic basis of diaphragmatic hernias may shed light on this unusual presentation and explain why other cases show no fusion.

Spinal cysticercosis mimicking a tumor in a pediatric patient.

Parasitic infections of the central nervous system (CNS) occur mostly in underdeveloped regions of the world. Neurocysticercosis (NC) occurs when the larval form of the T. solium tapeworm invades the CNS. Spinal cysticercosis is an extremely rare type of NC and occurs when the cyst occupies the subarachnoid space of the spinal column. Previous cases have been successfully treated through both surgical and medical means. The current case describes the symptoms, diagnosis, and treatment of a patient with this extremely uncommon manifestation of neurocysticercosis.