Chylomicron retention disease: a rare aetiology of failure to thrive.

The aetiology of failure to thrive (FTT) in children is broad, of which some conditions are extremely rare. It is important to consider these rarer conditions, especially in the setting of other concerning signs/symptoms or when there is no improvement with conventional treatment. In this case report we highlight such a rare condition-chylomicron retention disease (CRD) as an aetiology of FTT. CRD often presents with non-specific symptoms, resulting in delayed diagnosis which is established by genetic workup and histology from small intestinal biopsies. Despite being rare, CRD needs to be considered as one of the differential diagnoses after ruling out the more common causes of FTT.

Automatic renal carcinoma biopsy guidance using forward-viewing endoscopic optical coherence tomography and deep learning.

Percutaneous renal biopsy (PRB) is commonly used for kidney cancer diagnosis. However, current PRB remains challenging in sampling accuracy. This study introduces a forward-viewing optical coherence tomography (OCT) probe for differentiating tumor and normal tissues, aiming at precise PRB guidance. Five human kidneys and renal carcinoma samples were used to evaluate the performance of our probe. Based on their distinct OCT imaging features, tumor and normal renal tissues can be accurately distinguished. We examined the attenuation coefficient for tissue classification and achieved 98.19% tumor recognition accuracy, but underperformed for distinguishing normal tissues. We further developed convolutional neural networks (CNN) and evaluated two CNN architectures: ResNet50 and InceptionV3, yielding 99.51% and 99.48% accuracies for tumor recognition, and over 98.90% for normal tissues recognition. In conclusion, combining OCT and CNN significantly enhanced the PRB guidance, offering a promising guidance technology for improved kidney cancer diagnosis.

Pediatric Autoimmune Pancreatitis: A Single-Center Retrospective Case Series.

OBJECTIVES: Autoimmune pancreatitis (AIP) is a rare form of a chronic, immune-mediated, inflammatory pancreatic condition. There is limited data regarding presentation and outcome in the pediatric population. We described a single-center case series of 4 pediatric patients with AIP to better understand the presentation, symptoms, and outcomes of this rare condition. METHODS: Data collected included demographics, serology markers, symptoms at presentation, imaging, additional organ involvement, histology, treatment methods, and outcomes. The diagnosis of AIP was made by a combination of serology, pancreatic imaging, histology, extrapancreatic manifestations, and steroid response. RESULTS: All patients were diagnosed with type 2 AIP. Abdominal pain, emesis, and obstructive jaundice were the most common symptoms at presentation. Autoimmune markers were negative. Cross-sectional abdominal imaging showed diffuse/focal pancreatic gland enlargement and common bile duct stricture universally and main pancreatic duct irregularity in half of the patients. Biopsies showed lymphoplasmacytic infiltration with associated pancreatic fibrosis and atrophy. Treatment with an 8-week tapering course of prednisone showed prompt response with resolution of symptoms and normalization of laboratory test results. CONCLUSIONS: Our case series shows that AIP in children is a rare entity with a distinct clinical presentation, classical radiographic and histological features with good long-term prognosis.

The utility of TLE1 and BCOR as immunohistochemical markers for angiomatoid fibrous histiocytoma.

OBJECTIVES: Diagnosis of angiomatoid fibrous histiocytoma (AFH) can be challenging due to its variable histologic features and a lack of highly sensitive and/or specific immunohistochemical markers. The utility of TLE1 and BCOR as immunohistochemical markers for AFH is not known. METHODS: We examined the spectrum of histologic features of 36 AFHs, and studied the expression of both TLE1 and BCOR in AFH and its mimics by immunohistochemical staining. Positive nuclear expression was scored semiquantitatively. RESULTS: Both typical and unusual histologic features of AFHs were observed in this cohort. TLE1 was moderately to strongly positive in 36/36 AFHs, 4/4 synovial sarcomas, and 2/3 BCOR sarcomas; weakly positive in 4/6 inflammatory myofibroblastic tumors; negative in all dermatofibromas (n = 10), atypical fibrous histiocytomas (n = 5), myofibroma (n = 2) and juvenile xanthogranulomas (n = 5), with an overall sensitivity of 100%, and specificity of 71.4% for AFH. BCOR was moderately to strongly positive in 24/36 AFHs, 4/4 synovial sarcomas, 3/3 BCOR sarcomas, and 1/5 atypical fibrous histiocytomas; weakly positive in 10/36 AFHs; negative in the remaining tumors. The overall sensitivity and specificity of BCOR for AFH were 94.4% and 77.1%, respectively. CONCLUSIONS: TLE1 is a highly sensitive immunohistochemical marker for AFH.

Review of Pediatric Extraosseous Chordomas with a Unique, Illustrative Case.

INTRODUCTION: Chordoma is a rare, aggressive tumor that is believed to originate from notochord remnants. It can occur anywhere from the clivus to the sacrum and often recurs even after resection and radiotherapy. We present a unique case that initially suggested a different pathology based on imaging and presentation but was found to be a chordoma on gross and pathological analysis. CASE PRESENTATION: An 11-year-old girl presented outpatient for scoliosis evaluation and was found to have what appeared to be a right L4 peripheral nerve sheath tumor on MRI, causing dextroconvex scoliosis. She underwent a gross total resection via a retroperitoneal approach and was found to have what appeared to be an extraosseous, extradural, extra-spinal canal lumbar chordoma. Immunohistochemical features on surgical pathology were consistent with chordoma. The patient was referred to radiation oncology for adjuvant radiotherapy and pediatric hematology/oncology for recurrence monitoring. DISCUSSION: Our case is the first to present in such a manner, was shown to be external to the spinal canal, encasing the nerve root, and was the first such case in a pediatric patient. We reviewed the growing body of literature on spinal extraosseous chordomas and their characteristics within the pediatric patient population. We also reviewed chordoma pathogenesis theories as well as current and future treatment options.

Prognostic significance of NT5E/CD73 in neuroblastoma and its function in CSC stemness maintenance.

Cluster of differentiation 73 (CD73), a cell surface enzyme that catalyzes adenosine monophosphate (AMP) breakdown to adenosine, is differentially expressed in cancers and has prognostic significance. We investigated its expression profile in neuroblastoma (NB), its association with NB clinical outcomes, and its influence in the regulation of cancer stem cells' (CSCs) stemness maintenance. RNA-Seq data mining (22 independent study cohorts, total n = 3836) indicated that high CD73 can predict good NB prognosis. CD73 expression (immunohistochemistry) gauged in an NB patient cohort (n = 87) showed a positive correlation with longer overall survival (OS, P = 0.0239) and relapse-free survival (RFS, P = 0.0242). Similarly, high CD73 correlated with longer OS and RFS in advanced disease stages, MYCN non-amplified (MYCN-na), and Stage-4-MYCN-na subsets. Despite no definite association in children < 2 years old (2Y), high CD73 correlated with longer OS (P = 0.0294) and RFS (P = 0.0315) in children > 2Y. Consistently, high CD73 was associated with better OS in MYCN-na, high-risk, and stage-4 subsets of children > 2Y. Multivariate analysis identified CD73 as an independent (P = 0.001) prognostic factor for NB. Silencing CD73 in patient-derived (stage 4, progressive disease) CHLA-171 and CHLA-172 cells revealed cell-line-independent activation of 58 CSC stemness maintenance molecules (QPCR profiling). Overexpressing CD73 in CHLA-20 and CHLA-90 cells with low CD73 and silencing in CHLA-171 and CHLA-172 cells with high CD73 showed that CD73 regulates epithelial to mesenchymal transition (E-Cadherin, N-Cadherin, Vimentin), stemness maintenance (Sox2, Nanog, Oct3/4), self-renewal capacity (Notch), and differentiation inhibition (leukemia inhibitory factor, LIF) proteins (confocal-immunofluorescence). These results demonstrate that high CD73 can predict good prognosis in NB, and further suggest that CD73 regulates stemness maintenance in cells that defy clinical therapy.

COVID-19-Related Intussusception: A Case Series and Review of the Literature.

Background: Ileocolic intussusception is a common gastrointestinal emergency that occurs in infancy. Many cases are caused by anatomic lead points, such as hypertrophied Peyer's patches. Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection, which causes coronavirus disease 2019 (COVID-19), commonly presents with respiratory symptoms, however, its relation to intussusception remains unknown. Methods: Two cases are reported as well as a review of pertinent English-language literature on the topic. Results: We present two cases of intussusception in COVID-19-positive patients, including the first known case of a lead point with tissue polymerase chain reaction (PCR) confirming COVID-19 positivity, and compare these findings to a review of the recent literature. Intussusception in COVID-19-positive patients is becoming more prevalent and more often requires operative treatment. Discussion: We offer evidence that intussusception can be the presenting symptom in the absence of COVID-19-related respiratory symptoms. There also seems to be a trend toward the need for operative intervention compared with COVID-19-negative intussusception. The presence of SARS-CoV-2 can be confirmed via PCR in specific lead points (lymph nodes), directly causing the intussusception. Conclusions: Providers should have a low threshold to suspect and diagnose intussusception as operative treatment is more readily used in COVID-19-positive pediatric patients with gastrointestinal symptoms.

Placental Neutrophil Infiltration Associated with Tobacco Exposure but Not Development of Bronchopulmonary Dysplasia.

Objective: In utero inflammation is associated with bronchopulmonary dysplasia (BPD) in preterm infants. We hypothesized that maternal tobacco exposure (TE) might induce placental neutrophil infiltration, increasing the risk for BPD. Study design: We compared the composite outcome of BPD and death in a prospective pilot study of TE and no-TE mothers and their infants born <32 weeks. Placental neutrophil infiltration was approximated by neutrophil gelatinase-associated lipocalin (NGAL) ELISA, and total RNA expression was analyzed via NanoString© (Seattle, WA, USA). Result: Of 39 enrolled patients, 44% were classified as tobacco exposure. No significant difference was noted in the infant's composite outcome of BPD or death based on maternal tobacco exposure. NGAL was higher in placentas of TE vs. non-TE mothers (p < 0.05). Placental RNA analysis identified the upregulation of key inflammatory genes associated with maternal tobacco exposure. Conclusion: Tobacco exposure during pregnancy was associated with increased placental neutrophil markers and upregulated inflammatory gene expression. These findings were not associated with BPD.

Computer-aided Veress needle guidance using endoscopic optical coherence tomography and convolutional neural networks.

During laparoscopic surgery, the Veress needle is commonly used in pneumoperitoneum establishment. Precise placement of the Veress needle is still a challenge for the surgeon. In this study, a computer-aided endoscopic optical coherence tomography (OCT) system was developed to effectively and safely guide Veress needle insertion. This endoscopic system was tested by imaging subcutaneous fat, muscle, abdominal space, and the small intestine from swine samples to simulate the surgical process, including the situation with small intestine injury. Each tissue layer was visualized in OCT images with unique features and subsequently used to develop a system for automatic localization of the Veress needle tip by identifying tissue layers (or spaces) and estimating the needle-to-tissue distance. We used convolutional neural networks (CNNs) in automatic tissue classification and distance estimation. The average testing accuracy in tissue classification was 98.53 ± 0.39%, and the average testing relative error in distance estimation reached 4.42 ± 0.56% (36.09 ± 4.92 µm).

L-SIGN is a receptor on liver sinusoidal endothelial cells for SARS-CoV-2 virus.

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), remains a pandemic. Severe disease is associated with dysfunction of multiple organs, but some infected cells do not express ACE2, the canonical entry receptor for SARS-CoV-2. Here, we report that the C-type lectin receptor L-SIGN interacted in a Ca2+-dependent manner with high-mannose-type N-glycans on the SARS-CoV-2 spike protein. We found that L-SIGN was highly expressed on human liver sinusoidal endothelial cells (LSECs) and lymph node lymphatic endothelial cells but not on blood endothelial cells. Using high-resolution confocal microscopy imaging, we detected SARS-CoV-2 viral proteins within the LSECs from liver autopsy samples from patients with COVID-19. We found that both pseudo-typed virus enveloped with SARS-CoV-2 spike protein and authentic SARS-CoV-2 virus infected L-SIGN-expressing cells relative to control cells. Moreover, blocking L-SIGN function reduced CoV-2-type infection. These results indicate that L-SIGN is a receptor for SARS-CoV-2 infection. LSECs are major sources of the clotting factors vWF and factor VIII (FVIII). LSECs from liver autopsy samples from patients with COVID-19 expressed substantially higher levels of vWF and FVIII than LSECs from uninfected liver samples. Our data demonstrate that L-SIGN is an endothelial cell receptor for SARS-CoV-2 that may contribute to COVID-19-associated coagulopathy.

Intranasal and intrapulmonary vaccination with an M protein-deficient respiratory syncytial virus (RSV) vaccine improves clinical signs and reduces viral replication in infant baboons after an RSV challenge infection.

Respiratory syncytial virus (RSV) is the major viral respiratory pathogen for human infants and children. Despite a severe global burden incurred by annual RSV epidemics, there is no licensed RSV vaccine. We have developed an RSV vaccine from a human RSV strain from which the gene for the viral M protein has been deleted ("Mnull RSV"). RSV infects airway cells and produces each of its proteins. The M protein is responsible for reassembling the various other synthesized viral proteins into new, intact virus. In the absence of the M protein, therefore, reassembly does not occur, and the Mnull RSV does not replicate. We vaccinated 2-week old infant baboons with Mnull RSV either intranasally (IN) or directly into the lung (intratracheal, or IT), then infected these animals by inoculating human RSV directly into the lung. IN vaccination induced inconsistent serum RSV neutralizing antibody (NA) responses, but provided moderate reductions in respiratory rates, overall signs of illness and viral replication in bronchoalveolar lavage (BAL) fluid following infection. Intratracheal vaccination induced much stronger RSV NA responses, which persisted for at least 4-6 months. Following RSV infection, animals vaccinated by the IT route had much greater reductions in tachypnea and work of breathing than animals vaccinated IN, and had undetectable amounts of virus in BAL fluids. These results support the further development of IT Mnull RSV vaccination to reduce the impact of RSV infection in humans.

Small Cell Carcinoma of the Ovary, Hypercalcemic Type, in a 12-Month-Old Girl.

Small cell carcinoma of the ovary, hypercalcemic type (SCCOHT) is a highly aggressive malignant tumor affecting predominantly young adults and adolescents with an average age of 23.9 at time of diagnosis. Up to two thirds of patients have paraneoplastic hypercalcemia. The molecular signature of these tumors is SMARCA4 mutations, with somatic and germline pathogenic variants previously described. We report a case of a previously healthy one-year-old girl who was noticed to have mild anemia and an abdominal mass during a well-child visit. Further laboratory testing revealed hypercalcemia. A computerized tomography scan showed a left-sided ovarian mass (9.3 x 7.3 x 7 cm). The resection specimen showed a large ovarian tumor with solid tan-yellow cut surfaces and small foci of necrosis. Microscopically, the tumor was composed of sheets of small, hyperchromatic epithelioid cells with focal rhabdoid large cell morphology. The tumor cells were strongly and diffusely positive for WT1 (N-terminal antibodies) with focal EMA and Pan-keratin positivity. Absent SMARCA4 (BRG1) protein expression by immunohistochemistry ultimately established the diagnosis of small cell carcinoma of the ovary, hypercalcemic type. To our knowledge, this is the youngest patient reported in the literature.

Deep-learning-aided forward optical coherence tomography endoscope for percutaneous nephrostomy guidance.

Percutaneous renal access is the critical initial step in many medical settings. In order to obtain the best surgical outcome with minimum patient morbidity, an improved method for access to the renal calyx is needed. In our study, we built a forward-view optical coherence tomography (OCT) endoscopic system for percutaneous nephrostomy (PCN) guidance. Porcine kidneys were imaged in our experiment to demonstrate the feasibility of the imaging system. Three tissue types of porcine kidneys (renal cortex, medulla, and calyx) can be clearly distinguished due to the morphological and tissue differences from the OCT endoscopic images. To further improve the guidance efficacy and reduce the learning burden of the clinical doctors, a deep-learning-based computer aided diagnosis platform was developed to automatically classify the OCT images by the renal tissue types. Convolutional neural networks (CNN) were developed with labeled OCT images based on the ResNet34, MobileNetv2 and ResNet50 architectures. Nested cross-validation and testing was used to benchmark the classification performance with uncertainty quantification over 10 kidneys, which demonstrated robust performance over substantial biological variability among kidneys. ResNet50-based CNN models achieved an average classification accuracy of 82.6%±3.0%. The classification precisions were 79%±4% for cortex, 85%±6% for medulla, and 91%±5% for calyx and the classification recalls were 68%±11% for cortex, 91%±4% for medulla, and 89%±3% for calyx. Interpretation of the CNN predictions showed the discriminative characteristics in the OCT images of the three renal tissue types. The results validated the technical feasibility of using this novel imaging platform to automatically recognize the images of renal tissue structures ahead of the PCN needle in PCN surgery.

Supernumerary Testis Discovered Upon Workup of a Paratesticular Mass.

A supernumerary testis is a rare finding with limited description in the literature. Presentations of supernumerary testes vary and often involve initial discovery intraoperatively or in association with a separate condition. In this case report, we describe our experience of a patient with ultrasound imaging concerning for a left paratesticular mass. The patient was taken to the operating room where the mass was found to be an atrophic, supernumerary testis. We also address the specific anatomy encountered in our case and discuss both the intraoperative and post-operative management that resulted, in addition to reviewing relevant literature.

Yttrium-90 radioembolization in desmoplastic small round cell tumor with recurrent hepatic metastasis following hyperthermic intraperitoneal chemotherapy.

We report a case of a 26-year-old male who was diagnosed with metastatic desmoplastic small round cell tumor initially treated with systemic chemotherapy followed by tumor debulking and hyperthermic intra-peritoneal chemotherapy. The patient was in complete remission by clinical and imaging criteria for 11 months, until he developed bi-lobar hepatic disease, which was successfully treated with selective internal radiation therapy by Yttrium-90. The patient demonstrated liver-specific complete response on follow-up imaging obtained 18 months after the procedure.

PD-L1 expression in angiomatoid fibrous histiocytoma.

Angiomatoid fibrous histiocytoma (AFH) is a rare tumor of intermediate malignancy. Treatment options for unresectable and/or metastatic tumors are very limited. Immunotherapy with PD-1/PD-L1 inhibitors may be worth exploring. The aim of this study was to evaluate the expression of PD-L1 in AFHs. PD-L1 expression was assessed on 36 AFHs from 36 pediatric patients by immunohistochemical staining of PD-L1 (clone 22C3). Positivity was defined as membranous expression in ≥ 1% of either tumor or immune cells. The correlations between PD-L1 expression and clinicopathologic features were assessed. Two patients had lymph node metastasis. All patients underwent surgical resection; three of them also had systemic chemotherapy. Three patients had recurrence after initial resection; all patients were alive with a median follow-up of 2.5 years. Overall, twenty-two (61%) tumors were positively stained for PD-L1 and positivity was seen on both tumor and immune cells in eighteen of the 22 tumors. A positive correlation was found between tumor cell PD-L1 expression and CD8+ T-cell infiltration. There were no statistically significant differences between the status of PD-L1 expression and the clinicopathological features assessed. PD-L1 expression was identified in 61% of AFHs with a predominantly adaptive pattern. Our findings provide a rationale for future studies evaluating the potential of checkpoint immunotherapy for patients with unresectable and/or metastatic tumor.