Case Report: Rubella Virus-Induced Cutaneous Granulomas in Two Pediatric Patients With DNA Double Strand Breakage Repair Disorders - Outcome After Hematopoietic Stem Cell Transplantation

Cutaneous granulomas associated with rubella virus: A clinical review

Since the initial identification of vaccine-derived rubella virus (RuV) in the cutaneous granulomas of pediatric patients with inborn errors of immunity in 2014, more than 80 cases of RuV granulomas have been reported implicating both vaccine-derived and wild type RuV. Previously thought to arise exclusively in patients with significant immunocompromise, the identification of RuV granulomas in clinically immunocompetent patients adds nuance to our understanding of the interplay between host environment, immune dysregulation, and RuV granuloma formation. This review summarizes the literature on RuV granulomas including clinical and histopathologic features, proposed pathomechanisms supporting granuloma development, and potential therapeutic options. There is no standardized algorithm to guide the workup and diagnosis of suspected RuV granulomas. We highlight the importance of contributing RuV granuloma cases to ongoing Centers for Disease Control and Prevention surveillance efforts to monitor wild type and vaccine-derived RuV transmission. Studies advancing our understanding of RuV granulomas may provide insights into the role of viral infectious agents in granulomatous disease pathogenesis and guide the development of improved therapeutic options.

Rubella virus-associated necrotizing neutrophilic granuloma in a patient with common variable immunodeficiency

Patients with inborn errors of immunity (IEI) may develop granulomas in multiple organ systems including the skin. Vaccine strain rubella virus (RuV), part of the live attenuated measles, mumps, and rubella (MMR) vaccine, has been identified within these granulomas. RuV is typically found in macrophages; however, recently neutrophils have been identified as a novel cell type infected. Here, we present a case of RuV-associated cutaneous granuloma with RuV localized to neutrophils. A 46-year-old female with common variable immunodeficiency presented with verrucous papules and crusted plaques from the right knee to the distal shin of 20 years duration, associated with prior physical trauma. Biopsy specimen showed palisaded granulomas surrounding central necrosis with scattered aggregates of neutrophils. Vaccine-derived RuV was detected by molecular sequencing in lesional skin. Fluorescent immunohistochemistry with CD206, myeloperoxidase (MPO), and RV capsid (RVC) antibodies demonstrated that RuV localized to neutrophils but not macrophages. The clinical presentation, cutaneous findings, and likely presence of RVC-positive granulocytes in bone marrow provide potential support to the evolving hypothesis of persistent RuV within neutrophils contributing to chronic granulomatous inflammation in a milieu of immune dysregulation.

Ataxia-telangiectasia clinical trial landscape and the obstacles to overcome

INTRODUCTION

Ataxia telangiectasia (A-T) is a life-limiting autosomal recessive disease characterized by cerebellar degeneration, ocular telangiectasias, and sinopulmonary disease. Since there is no cure for A-T, the standard of care is primarily supportive.

AREAS COVERED

We review clinical trials available in PubMed from 1990 to 2023 focused on lessening A-T disease burden. These approaches include genetic interventions, such as antisense oligonucleotides, designed to ameliorate disease progression in patients with select mutations. These approaches also include pharmacologic treatments that target oxidative stress, inflammation, and mitochondrial exhaustion, to attenuate neurological progression in A-T. Finally, we discuss the use of biological immunotherapies for the treatment of malignancies and granulomatous disease, along with other supportive therapies being used for the treatment of pulmonary disease and metabolic syndrome.

EXPERT OPINION

Barriers to successful genetic and pharmacologic interventions in A-T include the need for personalized treatment approaches based on patient-specific ATM mutations and phenotypes, lack of an animal model for the neurologic phenotype, and extreme rarity of disease making large-scale randomized trials difficult to perform. Ongoing efforts are needed to diagnose patients earlier, discover more effective therapies, and include more individuals in clinical trials, with the goal to lessen disease burden and to find a cure for patients with A-T.