Paediatric inflammatory multisystem syndrome: temporally associated with SARS-CoV-2 (PIMS-TS) - A mimic of intra-abdominal malignancy.

We report the case of a school-aged boy who presented with clinical features suggesting acute appendicitis. However, further imaging which included CT, demonstrated an inflammatory mass involving the transverse colon raising the suspicion of lymphoma. He then developed intestinal obstruction, and in view of the rapid progression of the disease, he was thought to have non-Hodgkin's lymphoma. He underwent an open excisional biopsy, which revealed a necroinflammatory process and no suggestion of lymphoma or an alternative malignancy or specific diagnosis. His steroid treatment was stopped, and he made a good recovery postoperatively. Positive COVID-19 antibodies, positive response to steroids, results and clinical features were consistent with paediatric inflammatory multisystem syndrome (PIMS-TS), with extensive investigation not offering an alternative diagnosis.While PIMS-TS is a relatively new entity, we believe that this case highlights the importance of it being considered a differential diagnosis of a child presenting with an inflammatory mass.

ALK-positive histiocytosis: a new clinicopathologic spectrum highlighting neurologic involvement and responses to ALK inhibition.

ALK-positive histiocytosis is a rare subtype of histiocytic neoplasm first described in 2008 in 3 infants with multisystemic disease involving the liver and hematopoietic system. This entity has subsequently been documented in case reports and series to occupy a wider clinicopathologic spectrum with recurrent KIF5B-ALK fusions. The full clinicopathologic and molecular spectra of ALK-positive histiocytosis remain, however, poorly characterized. Here, we describe the largest study of ALK-positive histiocytosis to date, with detailed clinicopathologic data of 39 cases, including 37 cases with confirmed ALK rearrangements. The clinical spectrum comprised distinct clinical phenotypic groups: infants with multisystemic disease with liver and hematopoietic involvement, as originally described (Group 1A: 6/39), other patients with multisystemic disease (Group 1B: 10/39), and patients with single-system disease (Group 2: 23/39). Nineteen patients of the entire cohort (49%) had neurologic involvement (7 and 12 from Groups 1B and 2, respectively). Histology included classic xanthogranuloma features in almost one-third of cases, whereas the majority displayed a more densely cellular, monomorphic appearance without lipidized histiocytes but sometimes more spindled or epithelioid morphology. Neoplastic histiocytes were positive for macrophage markers and often conferred strong expression of phosphorylated extracellular signal-regulated kinase, confirming MAPK pathway activation. KIF5B-ALK fusions were detected in 27 patients, whereas CLTC-ALK, TPM3-ALK, TFG-ALK, EML4-ALK, and DCTN1-ALK fusions were identified in single cases. Robust and durable responses were observed in 11/11 patients treated with ALK inhibition, 10 with neurologic involvement. This study presents the existing clinicopathologic and molecular landscape of ALK-positive histiocytosis and provides guidance for the clinical management of this emerging histiocytic entity.

Histopathology of laryngomalacia.

BACKGROUND: Laryngomalacia is the commonest laryngeal anomaly and cause of stridor in children. Although most cases are self-limiting, failure to thrive, hypoxaemia or significant apnoeic episodes may warrant surgical intervention in the form of aryepiglottoplasty. Opinion is divided as to the pathophysiological mechanisms involved in the disease process. AIMS AND OBJECTIVES: This study explores the aetiology of laryngomalacia by reviewing the histology of aryepiglottoplasty resection specimens. MATERIAL AND METHODS: The histology reports of 61 aryepiglottoplasty specimens resected between 1 October 2014 and 31 October 2018 were reviewed. RESULTS: Age of patients ranged from 3 weeks to 36 months. 36 patients were male and 25 female. 43 of 61 (70.5%) cases had inflammation, most of which were mild. 3 (4.9%) cases had histological specimens with detectable eosinophils. None of the specimens had signs of granulomatous change, ulceration or calcification. Cartilage was present in the resected specimen in 47 (77%) cases. Over half of these (59.6%) were immature cartilage. CONCLUSION AND SIGNIFICANCE: The results suggest a mild concurrent laryngitis/supraglottitis in most cases. Eosinophilia is rare and does not support eosinophilic oesophageal reflux as part of the aetiology. The high proportion of immature cartilage in the specimens supports the theory of chondropathic aetiology.

Management of pediatric benign ovarian tumors in England and Egypt: A comparative study.

AIM OF THE STUDY: We aimed to compare the management of pediatric benign ovarian tumors between an English center and three Egyptian institutions. MATERIALS AND METHODS: This was a retrospective review of all children presenting with benign ovarian tumors between January 2014 and January 2019. A standardized dataset was used to compare between both sides. RESULTS: Eighty-nine patients were included (54 English and 35 Egyptians). Median age at diagnosis in England was 13 years (2-16y), while in Egypt it was 7 years (9m-16y) with P =0.001. Mature teratomas or dermoid cysts were the most common findings in England and Egypt; 75.9% and 82.8% of cases, respectively. The presentation with an acute abdomen represented 27.8% of English and 28.6% of Egyptian patients. Incidentally diagnosed lesions constituted 15% of English patients, whereas none of the Egyptian cases were discovered incidentally. There were variations in diagnostic imaging; England: Ultrasound (USS) (54), magnetic resonance imaging (MRI) (37), and computed tomography (CT) (only one)-Egypt: USS (35), CT (17), and MRI (only one). Minimally invasive surgery (MIS) was performed in 15% of English and 23% of Egyptian patients (P = 0.334). Ovarian-sparing surgery (OSS) was performed in: England 35%, Egypt 37%; P = 0.851. OSS was performed using MIS in 87.5% (7/8) of English patients and 100% (8/8) of Egyptians. Patients presented as emergencies generally had open oophorectomies: England; 86.7% open and 80% oophorectomy-Egypt; 100% open and 90% oophorectomy. Recurrences or metachronous disease occurred in 5.6% of English and 5.7% of Egyptian patients. CONCLUSIONS: There were no significant differences regarding surgical management, tumor pathology, and recurrence or metachronous disease. However, age, incidental diagnosis, and imaging modalities showed notable differences. MIS was correlated with ovarian preservation, whereas emergency surgery generally resulted in open oophorectomy.