In reference to Neck abscess: An unusual clinical presentation of immunoglobulin G4-related disease.

I read the article entitled “Neck Abscess: An Unusual Clinical Presentation of Immunoglobulin G4-Related Disease” (IgG4-RD) with great interest given our limited knowledge of the entity to date. Review of the article suggests that the patient had necrotizing granulomatous lymphadenitis, for which the most common associated diseases were ruled out. However, one rare cause of such an aggressive and refractory disease in an immunocompetent patient that was never specifically ruled out is tularemia. We recently encountered a case that was nearly identical to this one in terms of clinical presentation and pathologic, microbiologic, and imaging findings. It was not until we specifically tested for tularemia that the diagnosis was made. Though uncommon, tularemia is present in Italy and may have caused this patient’s symptoms. I think it is important that, before we include primary IgG4-RD in our differential diagnosis for cervical suppurative lymphadenitis with necrotizing granulomas, as this case report suggests, we make sure this case report did not instead identify a secondary IgG4 response to tularemia lymphadenitis.