Histopathologic features in a case of hyperimmunoglobulinemia D syndrome

A case of neonatal sweet syndrome associated with mevalonate kinase deficiency

BACKGROUND

Sweet syndrome (SS), also known as acute febrile neutrophilic dermatosis, is an immunologic syndrome characterized by widespread neutrophilic infiltration. Histiocytoid Sweet syndrome (H-SS) is a histopathologic variant of SS. While SS most commonly occurs in adults, this case report discusses an infant patient who presented with H-SS.

CASE PRESENTATION

Through a multidisciplinary approach, this patient was also found to have very early onset inflammatory bowel disease (VEO-IBD) and Mevalonate kinase-associated disease (MKAD). While prior case studies have characterized an association between VEO-IBD and MKAD, there is no literature describing the association of all three diagnoses this case: H-SS, VEO-IBD and MKAD. Initiation of canakinumab in this patient resulted in successful control of the disease.

CONCLUSIONS

This case highlights the importance of a multidisciplinary approach to rare diagnoses, and collaboration during cases with significant diagnostic uncertainty.

Hyper-immunoglobulin D syndrome with novel mutations in an afebrile infant

Hyper-immunoglobulin D syndrome is a rare autosomal-recessive autoinflammatory syndrome in which a mevalonate kinase deficiency results due to mutations of the mevalonate kinase gene. We report a case of an Asian male infant who was found to have hyper-immunoglobulin D syndrome in the absence of fever. His skin manifestations included cephalic pustulosis as well recurrent transient and fixed pink plaques and nodules on the face and extremities. Subsequent examination revealed hyper-immunoglobulin D syndrome with two novel allelic mutations in the mevalonate kinase gene: c.895G > A (p.D299N) and c.1168C > T (p.Q390). It is important for dermatologists to recognize the varied cutaneous presentations of hyper-immunoglobulin D syndrome because rapid diagnosis and treatment can significantly affect outcomes.

Vasculitis and vasculitis-like manifestations in monogenic autoinflammatory syndromes

Monogenic autoinflammatory syndromes are a rare group of disorders characterized by periodic episodes of systemic inflammation of endogenous origin. Sometimes, these diseases may present with features akin to vasculitis. We conducted a literature review on such vasculitic manifestations in described monogenic autoinflammatory syndromes utilizing the Online Mendelian Inheritance in Man (OMIM), Medline, and Scopus databases. Our search identified that Familial Mediterranean fever (FMF) can manifest with features of either small, medium, large, or variable-vessel vasculitis. Stimulator of interferon gene (STING)-associated vasculopathy of infancy (SAVI) is an interferonopathy that can mimic the presentation of medium-vessel or small-vessel vasculitis, whereas deficiency of adenosine deaminase 2 (DADA2) is another such mimic of medium-vessel vasculitis, associated in a significant number of patients with features of immunodeficiency. Occasional reports exist of vasculitic manifestations in tumor necrosis factor (TNF) receptor-associated periodic fever syndrome (TRAPS) and chronic infantile neurologic cutaneous and articular disorder (CINCA), whereas mevalonate kinase deficiency can also mimic the presentation of small- or medium-vessel vasculitis. Clinicians should be aware of the possibility of autoinflammatory disease presenting as vasculitis to diagnose and treat the same appropriately.