Lehman, Julia S.

AbstractBackgroundCalciphylaxis is a devastating multifactorial disorder of the subcutaneous fat that is known to be associated with hypercoagulability. Recent literature has proposed subclassifying patients with calciphylaxis as having warfarin‐associated or warfarin‐unassociated disease.AimWe aimed to determine whether patients with warfarin‐associated calciphylaxis differ clinically from patients with warfarin‐unassociated calciphylaxis.Materials and methodsWe performed a subgroup analysis of patients with nonuremic calciphylaxis from a previously studied cohort and compared clinical and outcomes features of patients who were taking warfarin at the time of disease onset to those of patients who were not.ResultsNineteen patients with nonuremic calciphylaxis were identified, including 10 (53%) who had been on warfarin at the time of disease onset and 9 (47%) who had not. Of all clinical and outcomes parameters tested, no significant differences were detected between the two groups.Discussion and ConclusionsThough this study is limited by its retrospective nature and the relatively small number of patients studied, available data do not support subclassifying patients with nonuremic calciphylaxis as having warfarin‐associated or warfarin‐unassociated disease. Rather, the body of literature would suggest that identification and correction of underlying disorders of hypercoagulability should be prioritized.

Cutaneous reactions to red tattoo pigment rarely manifest as pseudolymphomatous reactions. We describe an exceedingly rare case of red tattoo‐related T‐cell predominant pseudolymphoma microscopically mimicking mycosis fungoides. Careful clinicopathological correlation was required to obtain the correct diagnosis and aid in an effective treatment course.

Cutaneous reactions from targeted biologics are increasingly common. We describe a case of a cutaneous lichenoid drug eruption from the RANK inhibitor denosumab and a previously unreported lymphohistiocytic reaction pattern. The clinical and histopathological details of this case will aid in recognition, diagnosis, and treatment of drug rashes from denosumab.

Abstract: Calciphylaxis is a rare, painful, and life-threatening condition with a high mortality rate. Although the etiology of calciphylaxis is not well understood, it has been proposed that calcium deposition within and around subcutaneous vessels restricts blood flow chronically, thereby predisposing the patient to acute pannicular and dermal thrombosis. Given increasing recognition of the role of hypercoagulability in calciphylaxis, this retrospective cohort study sought to evaluate the presence of thromboses and dermal angioplasia in calciphylaxis. Moreover, we aimed to validate previous observations about the histopathology of calciphylaxis compared with skin biopsies from patients with end-stage renal disease but without calciphylaxis. After a meticulous clinical chart review, we assessed the corresponding skin biopsies for the presence of vessel calcification, thromboses, and dermal angioplasia in skin biopsies from patients with calciphylaxis (n = 57) and compared with those from patients with end-stage renal disease but without calciphylaxis (n = 26). Histopathologic findings were correlated with clinical features such as chronic kidney disease, diabetes, or associated malignancy. Our results validated a prior observation that calciphylaxis was significantly more likely to show calcification of dermal vessels and diffuse dermal thrombi. This study reports the frequent finding of dermal angioplasia, a potential marker of chronic low-grade ischemia, as another frequent microscopic finding in calciphylaxis. Among cases of calciphylaxis, histopathologic changes in patients with chronic kidney disease were indistinguishable from those in patients without chronic kidney disease, thereby implying a final common pathogenic pathway in both uremic and nonuremic calciphylaxis. In future, larger, prospective studies may be useful in validating these findings.

Background Periodic acid Schiff‐diastase ( PAS ‐D) staining is used routinely in dermatopathology. Conventionally, parakeratosis or intracorneal neutrophils justify use of PAS ‐D stain to identify dermatophytosis. We aimed to investigate the histopathological features of superficial dermatophytosis. Methods Skin biopsies with PAS ‐D stain were retrospectively reviewed by a blinded dermatopathologist. Histopathologic findings in cases with dermatophytosis were compared with those without. Results We studied 110 cases, of which 63 were PAS ‐D positive for dermatophytes. Dermatophytes were identified on hematoxylin and eosin (H&E) staining in 49 (77.8%) of the PAS ‐D‐positive cases. Diffuse compact orthokeratosis (79.37%, p < 0.001) and focal parakeratosis (65.08%, p = 0.03) were significantly more frequent in dermatophytosis. Intracorneal neutrophils and spongiosis were not significant findings. Fungal elements were frequently observed within compact orthokeratosis (62.0%) and parakeratosis (31.8%) but rarely within intracorneal pustules (12.7%). In some dermatophyte cases, intracorneal neutrophils (47.6%) or parakeratosis (17.5%) were absent. Conclusions Compact orthokeratosis or focal parakeratosis justifies PAS ‐D staining, whereas the absence of intracorneal neutrophils or parakeratosis is insufficient to exclude dermatophytosis. Results indicate that having a low threshold to perform PAS‐D stain is justified. PAS‐D stain may be deferred until H&E slides have been evaluated.