Dupilumab-induced psoriasiform dermatitis in two pediatric cardiac transplant patients.

Dupilumab is an interleukin-4 receptor antagonist important in the treatment of refractory atopic dermatitis (AD), particularly among pediatric patients. Two boys with a history of AD and cardiac transplant who developed psoriasiform dermatitis in response to dupilumab therapy are reported. These patients paradoxically developed an immune-mediated adverse drug reaction despite taking systemic immunosuppressive agents. While the literature suggests possible pathomechanisms for psoriasiform dermatitis despite immunosuppression, further research is necessary to better characterize this unique and unexpected phenomenon.

Toward a new model of childhood asthma care: community needs assessment in an underserved urban population.

OBJECTIVES: The objective of this study was to utilize a community-engaged research approach to better understand gaps and opportunities for improving asthma care from the perspectives of patients, caregivers, community organization representatives, and healthcare providers in a predominantly minority community. METHODS: Forty-one participants from four groups (patients, caregivers, community organization representatives, healthcare providers) participated in interviews or focus groups. A phenomenological approach to this qualitative research allowed the research team to better understand the lived experiences of families seeking asthma care in this community. RESULTS: Five gaps and five corresponding opportunities were identified. The gaps identified were unequal healthcare resource distribution; underrepresentation of health professionals from diverse backgrounds; experiences of environmental racism; mistrust, bias, and discrimination in healthcare encounters; and systemic marginalization of communities. The opportunities identified include increasing healthcare infrastructure and accessibility; increasing racially, culturally, and linguistically congruent healthcare; implementing equitable improvements to the built environment; building relationships with communities and individuals; and acknowledging communities' strengths and resilience. CONCLUSION: This study identified systemic gaps to asthma care that are of prominent concern to the community.

Heterozygous FOXN1 Variants Cause Low TRECs and Severe T Cell Lymphopenia, Revealing a Crucial Role of FOXN1 in Supporting Early Thymopoiesis.

FOXN1 is the master regulatory gene of thymic epithelium development. FOXN1 deficiency leads to thymic aplasia, alopecia, and nail dystrophy, accounting for the nude/severe combined immunodeficiency (nu/SCID) phenotype in humans and mice. We identified several newborns with low levels of T cell receptor excision circles (TRECs) and T cell lymphopenia at birth, who carried heterozygous loss-of-function FOXN1 variants. Longitudinal analysis showed persistent T cell lymphopenia during infancy, often associated with nail dystrophy. Adult individuals with heterozygous FOXN1 variants had in most cases normal CD4+ but lower than normal CD8+ cell counts. We hypothesized a FOXN1 gene dosage effect on the function of thymic epithelial cells (TECs) and thymopoiesis and postulated that these effects would be more prominent early in life. To test this hypothesis, we analyzed TEC subset frequency and phenotype, early thymic progenitor (ETP) cell count, and expression of FOXN1 target genes (Ccl25, Cxcl12, Dll4, Scf, Psmb11, Prss16, and Cd83) in Foxn1nu/+ (nu/+) mice and age-matched wild-type (+/+) littermate controls. Both the frequency and the absolute count of ETP were significantly reduced in nu/+ mice up to 3 weeks of age. Analysis of the TEC compartment showed reduced expression of FOXN1 target genes and delayed maturation of the medullary TEC compartment in nu/+ mice. These observations establish a FOXN1 gene dosage effect on thymic function and identify FOXN1 haploinsufficiency as an important genetic determinant of T cell lymphopenia at birth.

Persistent Hyper IgA as a Marker of Immune Deficiency: A Case Report.

An elevated IgA level obtained in a 10-year-old male a year after an episode of pneumococcal sepsis led to the discovery of a broad-based IgG-specific antibody deficiency syndrome. The specifics of the case and pertinent literature are presented, including a discussion of the hyper-IgD syndrome. An elevated IgA, greater than two standard deviations above the expected age range should prompt a complete workup for selective antibody deficiency syndrome and adds an additional associated marker of an indolent hyper-IgD syndrome in a different clinical circumstance, although the lack of antibody response to vaccines is atypical of the hyper-IgD syndrome.