Refractory iron deficiency anemia (IDA) in children should be investigated beyond dietary deficiency, particularly when accompanied by growth faltering or hypoalbuminemia. PTEN hamartoma tumor syndrome, which includes the Bannayan–Riley– Ruvalcaba syndrome (BRRS) spectrum, may cause diffuse gastrointestinal polyposis, resulting in chronic occult blood and protein loss. We report the case of a girl born in 2015 who presented at the age of two years with severe IDA (hemoglobin 5.0 g/dL, mean corpuscular volume 53.6 fL). Oral iron therapy was initiated, followed by intermittent intravenous iron infusions at progressively shorter intervals; however, the anemia recurred. Stool occult blood and fecal calprotectin test results were consistently negative during this period. Endoscopy and capsule endoscopy revealed diffuse gastrointestinal polyposis, including numerous small bowel polyps with ulcerative features. Genetic analysis revealed a heterozygous pathogenic variant in PTEN, NM_000314.8:c.389G＞A (p.Arg130Gln). Despite endoscopic polypectomy and oral nutritional supplementation, IDA, hypoalbuminemia (albumin, 2.5-3.2 g/dL), and growth faltering persisted. Extraintestinal findings included macrocephaly, lipomatous masses, a subcutaneous hamartoma, and brain magnetic resonance imaging findings consistent with BRRS. Sirolimus therapy was initiated in September 2025, targeting a trough level of 6-10 ng/mL. By 6 months, hemoglobin stabilized at 12.9 g/dL, albumin normalized to 4.4 g/dL, weight increased by 5.1 kg, body mass index improved from below the 3rd percentile to the 10th percentile, and intravenous iron was no longer required. This case suggests that sirolimus may be beneficial in the treatment of diffuse PTEN-related gastrointestinal polyposis when endoscopic management is insufficient.

Background/Aims: Metabolic dysfunction-associated steatotic liver disease (MASLD) is characterized by fat accumulation in the liver. MASLD encompasses both steatosis and MASH. Since MASH can lead to cirrhosis and liver cancer, steatosis and MASH must be distinguished during patient treatment. Here, we investigate the genomes, epigenomes, and transcriptomes of MASLD patients to identify signature gene set for more accurate tracking of MASLD progression. Methods: Biopsy-tissue and blood samples from patients with 134 MASLD, comprising 60 steatosis and 74 MASH patients were performed omics analysis. SVM learning algorithm were used to calculate most predictive features. Linear regression was applied to find signature gene set that distinguish the stage of MASLD and to validate their application into independent cohort of MASLD. Results: After performing WGS, WES, WGBS, and total RNA-seq on 134 biopsy samples from confirmed MASLD patients, we provided 1,955 MASLD-associated features, out of 3,176 somatic variant callings, 58 DMRs, and 1,393 DEGs that track MASLD progression. Then, we used a SVM learning algorithm to analyze the data and select the most predictive features. Using linear regression, we identified a signature gene set capable of differentiating the various stages of MASLD and verified it in different independent cohorts of MASLD and a liver cancer cohort. Conclusions We identified a signature gene set (i.e., CAPG, HYAL3, WIPI1, TREM2, SPP1, and RNASE6) with strong potential as a panel of diagnostic genes of MASLD-associated disease.

A 4-month-old intact male Sapsaree dog was referred due to a history of postprandial regurgitation following consumption of solid food. Thoracic radiography revealed focal leftward displacement of the thoracic trachea at T1 to T4 vertebrae levels. Barium contrast radiography revealed focal dilation of the cranial thoracic esophagus at the heart base level. Persistent right aortic arch (PRAA) with an aberrant left subclavian artery branching from the patent ductus arteriosus was diagnosed by computed tomography angiography (CTA). Although barium contrast radiography can presumptive diagnose PRAA, CTA should be considered for identifying additional vascular anomalies, specific types, and surgical planning.

A 3-year-old spayed female Russian blue cat was presented for dyspnea, nasal discharge, and stertorous breathing. Plain thoracic radiography revealed no specific findings. Computed tomography (CT) was performed to differentiate upper airway tract disorders. It revealed the presence of an iso-attenuating mass measuring 10.0 × 7.9 × 15.6 mm, with mild homogeneous contrast enhancement occupying the rostral nasopharynx. The mass was surgically debulked via a longitudinal incision in the soft palate. Histopathological and immunohistochemistry analysis of the surgically excised mass revealed CD3–/ CD79a+ B cell lymphoma with an incomplete margin. The patient underwent hypofractionated radiation therapy, receiving a total of 36 Gray (Gy) in 6 Gy fractions over a six-week period. A follow-up CT examination was performed after 27 months of irradiation and the patient was confirmed to have achieved a complete response. There were no complications related to irradiation. The patient was alive for 40 months without recurrence. This study suggests that hypofractionated radiation therapy combined with surgical debulking could be considered as a treatment option for feline nasopharyngeal lymphoma.

A 13-year-old male neutered Miniature Pinscher presented with coughing and dyspnea. The dog had been coughing for the past 4 weeks. The patient had mild dehydration on physical examination, and muffled heart sounds were detected. Thoracic radiographs revealed pleural effusion, which was consistent with chylous effusion based on cytological and biochemical evaluations. Computed tomography (CT) lymphangiography, which was performed via intrametatarsal pad injection, revealed no evidence of thoracic duct rupture or obvious leakage. On CT angiography (CTA), an intraluminal filling defect was identified in the cranial vena cava (CrVC). CrVC thrombosis with secondary chylothorax was diagnosed based on CT lymphangiography and CTA. Clopidogrel, rivaroxaban, and recombinant tissue-plasminogen activator were prescribed. The follow-up CTA, 4 months after diagnosis, revealed a decrease in the thrombus, and no pleural effusion was identified. Although CrVC thrombosis is an uncommon presentation in veterinary patients, thrombus in the CrVC should be considered as a differential diagnosis of chylothorax in dogs. CT lymphangiography and CTA could be helpful in identifying and differentiating the underlying etiologies of chylothorax.

The hyperglycemic hyperosmolar state (HHS) is considered the most fatal complication of type 2 diabetes mellitus (DM). The number of case reports describing pediatric HHS has increased recently in parallel with obesity and the prevalence of type 2 DM in pediatric patients. In this study, we investigated the patient characteristics and outcomes of HHS in 9 adolescents with obesity and type 2 DM. Almost all patients exhibited mixed clinical features of HHS and diabetic ketoacidosis (DKA), including characteristics such as hyperosmolality and ketoacidosis. These features made definitive diagnosis difficult; 5 out of 9 patients were initially diagnosed with DKA and were treated accordingly. Patients who were initially diagnosed with HHS received a more vigorous and appropriate fluid replacement than other patients did. No patients died, although 3 exhibited complications, such as arrhythmia, acute kidney injury requiring renal replacement therapy, rhabdomyolysis, and acute pancreatitis. Hyperosmolality with consequent severe dehydration is considered a significant factor contributing to the outcomes of patients with HHS. Therefore, early recognition of hyperosmolality is crucial for an appropriate diagnosis and adequate fluid rehydration to restore perfusion in the early period of treatment to improve patient outcomes for this rare but serious emerging condition in pediatric patients.

Iron deficiency is the most common nutritional deficiency in children and adolescents. Pediatric collagenous gastritis (CG) is a rare gastrointestinal disorder. Abdominal pain associated with iron deficiency anemia (IDA) is a common clinical symptom.We present three cases of pediatric CG diagnosed during the treatment of recurrent IDA. During esophagogastroduodenoscopy (EGD), nodularity of the gastric corpus was observed, which is a characteristic finding in pediatric patients with CG.Although pediatric CG could not be diagnosed by general EGD biopsy and pathological examination, it was diagnosed after suspecting pediatric CG and performing appropriate diagnostic tests. We recommend EGD for pediatric patients with recurrent IDA, especially for those with gastrointestinal symptoms. Moreover, when performing EGD, conducting appropriate examinations for pediatric CG is necessary.

Sjögren's syndrome (SS) is an autoimmune disease characterized by dryness of the mouth and eyes. The glandular dysfunction in SS involves not only T cell-mediated destruction of the glands but also autoantibodies against the type 3 muscarinic acetylcholine receptor or aquaporin 5 (AQP5) that interfere with the secretion process. Studies on the breakage of tolerance and induction of autoantibodies to these autoantigens could benefit SS patients. To break tolerance, we utilized a PmE-L peptide derived from the AQP5-homologous aquaporin of Prevotella melaninogenica (PmAqp) that contained both a B cell “E” epitope and a T cell epitope. Repeated subcutaneous immunization of C57BL/6 mice with the PmE-L peptide efficiently induced the production of Abs against the “E” epitope of mouse/human AQP5 (AQP5E), and we aimed to characterize the antigen specificity, the sequences of AQP5Especific B cell receptors, and salivary gland phenotypes of these mice. Sera containing anti-AQP5E IgG not only stained mouse Aqp5 expressed in the submandibular glands but also detected PmApq and PmE-L by immunoblotting, suggesting molecular mimicry.Characterization of the AQP5E-specific autoantibodies selected from the screening of phage display Ab libraries and mapping of the B cell receptor repertoires revealed that the AQP5E-specific B cells acquired the ability to bind to the Ag through cumulative somatic hypermutation. Importantly, animals with anti-AQP5E Abs had decreased salivary flow rates without immune cell infiltration into the salivary glands. This model will be useful for investigating the role of anti-AQP5 autoantibodies in glandular dysfunction in SS and testing new therapeutics targeting autoantibody production.