Keith, Phillip J.

Abstract Lysinibacillus massiliensis, formerly Bacillus massiliensis, is an environmental Gram-positive bacillus that is generally non-pathogenic. Rare case reports in immunosuppressed patients have described sepsis with this organism. In this study, we report a case of L massiliensis as a cause of infectious panniculitis mimicking erythema nodosum after infusion of autologous adipose-derived stem cells in an immunosuppressed patient with refractory Crohn’s disease. This case highlights the importance of care providers to consider exposures and host factors when interpreting culture results with otherwise benign organisms.

BackgroundThe classic histopathologic features of lichen sclerosus et atrophicus (LS) include lymphoplasmacytic inflammation below a zone of dermal edema and sclerosis. The presence of eosinophils in LS has received little attention, but the finding of tissue eosinophils, particularly eosinophilic spongiosis in LS, has been suggested as a marker for the coexistence of autoimmune bullous disease or allergic contact dermatitis (or both). We sought to determine whether the histopathologic presence of dermal eosinophils or eosinophilic spongiosis (or both) in biopsies from patients with LS is associated with autoimmune bullous disease, autoimmune connective tissue disease or allergic contact dermatitis.MethodsA retrospective review of the histopathology and medical records of 235 patients with LS who were evaluated from June 1992 to June 2012 was performed.ResultsSixty‐nine patients (29%) had eosinophils on histopathology. Among patients with associated diseases, a statistically significant association between the eosinophil cohort and the cohort without eosinophils was not detected.ConclusionsThe importance of eosinophils is uncertain, but our data suggest that the finding of tissue eosinophils alone is not sufficient to prompt an extensive workup for additional diagnoses.

AbstractHobnail hemangioma (HH), initially termed targetoid hemosiderotic hemangioma, is a rare, often solitary lesion classically characterized by a central brown or violaceous papulonodule surrounded at times by an ecchymotic halo. This lesion is typically found on the trunk or limbs of children or young to middle‐aged adults. Numerous case reports have found HHs to have a reproducible histologic appearance. Although the exact histogenesis of these lesions is unknown, multiple recent immunohistochemical studies suggest a lymphatic origin of these lesions. We present six cases of children with HHs with classic histology but with variability in their clinical appearance. Because the clinical presence of a targetoid halo is inconsistent and the hobnail phenomenon is not specific, we favor the designation of superficial hemosiderotic lymphovascular malformation instead of HH or targetoid hemosiderotic hemangioma as a more unifying term for this rare clinical entity. By eliminating confounding terminologies (in this case, incorporation of “hemangioma” in the name of this entity), we also hope to encourage a swifter change in practice to move away from erroneous diagnostic considerations.