Pathogenic role and diagnostic utility of interferon-α in histiocytic necrotizing lymphadenitis.

PURPOSE: Histiocytic necrotizing lymphadenitis (HNL) is an inflammatory disease of unknown etiology clinically characterized by painful lymphadenopathy. This study aimed to investigate the role of interferon (IFN)-α in the pathogenesis of HNL and the clinical significance of serum IFN-α levels for the diagnosis and monitoring of HNL disease activity. METHODS: This study enrolled 47 patients with HNL and 43 patients with other inflammatory diseases that require HNL differentiation including malignant lymphoma (ML), bacterial lymphadenitis, and Kawasaki disease. Expression of IFN-stimulated genes (ISGs) and MX1 in the lymph nodes was measured by real-time quantitative reverse transcription polymerase chain reaction and immunofluorescence staining, respectively. Enzyme-linked immunosorbent assay was used to quantify serum cytokine levels. The results were compared with the clinical features and disease course of HNL. RESULTS: Patients with HNL had a significantly elevated ISG expression in the lymph nodes compared with those with ML. MX1 and CD123, a specific marker of plasmacytoid dendritic cells (pDCs), were colocalized. In patients with HNL, serum IFN-α levels were significantly elevated and positively correlated with disease activity. The serum IFN-α level cutoff value for differentiating HNL from other diseases was 11.5 pg/mL. CONCLUSION: IFN-α overproduction from pDCs may play a critical role in HNL pathogenesis. The serum IFN-α level may be a valuable biomarker for the diagnosis and monitoring of disease activity in patients with HNL.

Case Report: A neonatal case of cryopyrin-associated periodic syndrome with severe funisitis and neonatal asphyxia.

Cryopyrin-associated periodic syndrome (CAPS) is a genetic disorder and autoinflammatory disease characterized by chronic inflammation throughout the body. The most severe form of CAPS, Chronic Infantile Neurologic Cutaneous, and Articular (CINCA) syndrome, also known as Neonatal Onset Multisystem Inflammatory Disease (NOMID), has three main features: skin rash, CNS involvement, and joint symptoms. Although these symptoms are typically reported shortly after birth, there have been a few reports of prenatal inflammation. Here, we report our experience managing a case of a CAPS infant born in severe neonatal asphyxia due to a ruptured cord associated with severe funisitis. The baby was born at 38 weeks and 6 days of gestation, weighing 2,898 g, through an ultra-emergency Caesarian section prompted by variable deceleration. The Apgar score was 1 point at 1 min and 4 points at 5 min, necessitating intensive care due to hypoxic-ischemic encephalopathy. Upon delivery, it was observed that the umbilical cord had partially ruptured at the site of attachment to the baby, accompanied by arterial hemorrhage. Umbilical cord rupture was considered to be the cause of the sudden decrease in fetal heart rate. Pathological examination also showed that the inflammation of the cord was more severe on the side attached to the fetus and on the arterial side, suggesting that the inflammation had extended from the fetus. The father carried a genetic mutation associated with CINCA syndrome/NOMID (NLRP3 c.2068G>A p.Glu690Lys Hetero), which was also found in the child. Histopathologic examination of the placenta and umbilical cord can provide crucial insights into the intrauterine onset of inflammation, which is the first manifestation of CINCA syndrome/NOMID in newborns. It should be noted that births with a genetic predisposition to CAPS may have complications related to the placenta and umbilical cord.

Clinical Usefulness of T-Cell Receptor Vß Repertoire Analysis for Differentiating Multisystem Inflammatory Syndrome in Japanese Children From Toxic Shock Syndrome and Kawasaki Disease.

The specific expansion of T-cell receptor ß chain variable region (TCR-Vß21.3 + ) CD4 + and CD8 + T cells was observed in Japanese patients with multisystem inflammatory syndrome in children. In contrast, these findings were not observed in patients with toxic shock syndrome and Kawasaki disease. T-cell receptor ß chain variable region repertoire analysis to detect specific expansion of Vß21.3 + T cells might be useful for differentiating multisystem inflammatory syndrome in children from toxic shock syndrome and Kawasaki disease.

A novel SLC5A2 heterozygous variant in a family with familial renal glucosuria.

Familial renal glucosuria (FRG) is characterized by persistent glucosuria despite normal blood glucose levels in the absence of overt tubular dysfunction. SGLT2 is a sodium-glucose cotransporter expressed in the proximal tubule; loss-of-function variants in SLC5A2 are the primary cause of FRG. Heterozygous variants have rarely been reported in Japanese individuals. Here, we identified a novel SLC5A2 heterozygous variant, c.1348G>T: p.Gly450Trp, in a Japanese family comprising two children and their father.