Idiopathic multicentric Castleman disease with TAFRO clinical subtype responsive to IL-6/JAK inhibition: A pediatric case series.

TAFRO (thrombocytopenia, anasarca, fever/elevated C-reactive protein, reticulin myelofibrosis, renal dysfunction, and organomegaly) clinical subtype of idiopathic multicentric Castleman disease (iMCD-TAFRO) is a rare lymphoproliferative disease characterized by systemic inflammation. First-line treatment for iMCD-TAFRO includes steroids and interleukin (IL)-6 blockade. Many patients have refractory disease, which is associated with significant morbidity and mortality, and treatment remains challenging. We present two pediatric cases of iMCD-TAFRO. One patient responded to IL-6 blockade; the other was refractory to siltuximab and chemotherapy, ultimately responding to JAK inhibition with ruxolitinib. This is the first reported pediatric case of refractory iMCD-TAFRO responding to JAK inhibition.

Differentiated Thyroid Cancer in the Pediatric/Adolescent Population: Evolution of Treatment.

Differentiated thyroid cancer (DTC) is the most common cancer in adolescents and young adults. In 2015, the American Thyroid Association published guidelines for management of pediatric DTC. We report our institutional experience and highlight changing practices and new opportunities. A retrospective analysis of all patients diagnosed with DTC from 2001 to 2016 was performed. Among 59 eligible patients, 31 (53%), 15 (25%), and 13 (22%) had low-risk, intermediate-risk, and high-risk disease, respectively. Half (15/31) of low-risk and all intermediate-risk/high-risk patients received radioactive iodine (I-131) ablation. For low-risk patients, average I-131 dose decreased from 80 to 42.05 mCi, and the percentage of patients who received I-131 decreased over time. Eleven of 16 patients with tumor genomic data were found to have somatic targetable (n=6) or germline (n=5) mutations. Persistent/recurrent disease was only present in high-risk (n=8) and intermediate-risk (n=1) patients. Two patients with iodine-refractory disease received trametinib to enhance radioiodine uptake. All patients were alive at follow-up (median, 5 y; range, 1 to 15 y). Coincident with the recent American Thyroid Association guidelines, the use of I-131 in low-risk patients has decreased over time in our practice. Tumor sequencing and cancer genetic evaluation may help redefine opportunities for treatment of high-risk patients and family counseling.

What's in a name: defining pediatric refractory ITP.

There are no agreed upon terminology to define "refractory" pediatric Immune Thrombocytopenia (ITP). Guidelines are therefore limited to arbitrary and outdated definitions. The Pediatric ITP Consortium of North America held a meeting in 2023 to define this entity. With 100% agreement, the faculty established that pediatric ITP that is refractory to emergent therapy could be defined as no platelet response after treatment with all eligible emergent pharmacotherapies. With 100% agreement, the working group established that pediatric patients with ITP that continue to demonstrate high disease burden and/or no platelet response despite treatment with multiple classes of disease modifying therapies represent a challenging subset of ITP. These patients are at higher risk of ongoing disease burden and merit additional investigation as well as consideration for clinical trials or novel therapies. Future efforts to define disease burden and disease response will be completed in collaboration with the ITP International Working Group.

GATA2 deficiency detected by newborn screening for SCID: A case report.

The early diagnosis and treatment of inborn errors of immunity (IEI) is crucial in reducing the morbidity and mortality due to these disorders. The institution of newborn screening (NBS) for the diagnosis of Severe Combined Immune Deficiency (SCID) has decreased the mortality of this disorder and led to the discovery of novel genetic defects that cause this disease. GATA2 deficiency is an autosomal dominant, pleiotropic disease with clinical manifestations that include bone marrow failure, monocyte and B cell deficiency, leukemia, pulmonary alveolar proteinosis and lymphedema. We present the case of an infant identified by newborn screening for SCID due to GATA2 deficiency.

A painless erythematous swelling of the external ear as a manifestation of Lyme disease: a case report.

BACKGROUND: Lyme disease is the most common tick-borne illness in the USA, Canada, and Europe. Clinical manifestations vary greatly, with localized skin findings functioning as early signs of the disease, followed by disseminated disease. The rarest dermatologic presentation of Lyme is a borrelial lymphocytoma, occurring distinctly in Europe and caused typically by Borrelia afzelii. CASE PRESENTATION: We report a case of a Caucasian 5-year-old European-American boy with slowly progressing, painless edema and erythema of his right pinna. Travel history revealed significant exposure to ticks during a recent trip to Eastern Europe. Laboratory testing for Borrelia burgdorferi demonstrated mixed positivity. He was treated with a 21-day course of amoxicillin, with complete resolution of symptoms and no sign of secondary Lyme disease. CONCLUSIONS: Borrelial lymphocytoma is a rare manifestation of Lyme disease in North America, although not uncommon in Europe. Diagnosis is made by the presence of a painless erythematous swelling typically found on the ear lobe, nipples, or testes. Laboratory tests are available but with low sensitivity, therefore, a high index of suspicion is necessary for a clinical diagnosis to be made. Treatment for isolated borrelial lymphocytoma is doxycycline 4 mg/kg up to 100 mg twice daily, whereas for children less than 8 years of age amoxicillin 50 mg/kg divided three times daily, for 3-4 weeks, is preferred.

Mechanisms coupling thrombin to metastasis and tumorigenesis.

The association of malignancy and thrombophilia is bidirectional, as evidenced by four decades of studies in animal models showing that hemostatic system components support cancer progression. Consistent with this view, clinical studies have suggested that anticoagulants not only limit thromboembolic complications associated with cancer, but also improve survival by impeding cancer progression, and may even prevent the development of cancer. In order to fully capitalize on this association, a detailed understanding of the mechanisms coupling hemostatic factors to cancer pathogenesis is required. Multiple studies have shown that thrombin-mediated procoagulant functions strongly promote metastatic potential. In particular, the platelet/fibrin(ogen) axis has been shown to protect newly formed micrometastases from innate immune surveillance, contribute to creation of a metastatic niche by recruitment of prometastatic inflammatory cells, and promote the epithelial to mesenchymal transition of metastatic cells. Thrombin-mediated functions have also been shown to support tumor growth in some contexts, and have even been linked to tumorigenesis in the setting of inflammation-driven colon cancer. Here, local thrombin-mediated extravascular fibrin deposition, and specifically fibrin-αMß2 integrin interaction, push intestinal inflammatory cells toward a pro-tumorigenic phenotype, resulting in the elaboration of key cytokines and growth factors that support the proliferation and survival of transformed intestinal epithelial cells. These studies reveal that hemostatic factors can serve as a bridge between pathological inflammation and the development of cancer. As a large proportion of cancers are caused by pathological inflammation, these studies suggest that therapies targeting the nexus between hemostasis and inflammation could be used to prevent cancer development.