Neutrophilic Infiltrates in Panniculitis: Comprehensive Review and Diagnostic Algorithm Proposal.

Neutrophilic infiltrates in panniculitis can be seen in different clinical-pathological entities. There are a "mostly neutrophilic inflammatory infiltrate" in some entities classically defined as neutrophilic panniculitis and already included in algorithms, such as enzymatic panniculitis, infective and factitial ones, erythema induratum, or subcutaneous Sweet syndrome, but there are also other panniculitis where neutrophils are frequently observed such as panniculitis associated with inflammatory bowel disease or rheumatoid arthritis, or drug-induced panniculitis associated with BRAF inhibitors, and finally, some panniculitis are better classified in other panniculitides groups but may present with neutrophil-rich variants, such as the neutrophil-rich subcutaneous fat necrosis of the newborn. We review the main clinical and histopathological features of most of these panniculitides and construct a diagnostic algorithm including these diseases.

Interstitial granulomatous dermatitis following tocilizumab, a paradoxical reaction?

Interstitial granulomatous dermatitis (IGD) is a rare dermatosis generally seen in the setting of rheumatic diseases, but also hematological disorders, internal malignances, infections, or drug induced. Herein, we report an exceptional case of an IGD with a clear chronological association with tocilizumab onset and cessation in a patient with adult-onset Still's disease. We review the granulomatous cutaneous reactions so far reported with this novel therapy: sarcoidosis, granuloma annulare, and IGD. Tocilizumab is a humanized anti-interleukin 6 receptor monoclonal antibody useful for the treatment of various systemic inflammatory disorders. Lately, it has found useful also for granulomatous diseases such as giant cell arteritis and even a promising response in IGD. Therefore, we believe our case adds the possibility of an IGD presenting as a paradoxical reaction.

Cutaneous Light Chain Deposition Disease: A Report of 2 Cases and Review of the Literature.

Light chain deposition disease (LCDD) is a rare systemic disorder with deposition of mostly monoclonal amorphous nonamyloid light chains in multiple organs. Renal involvement with rapidly progressing renal failure presents the dominant manifestation of LCDD. Approximately 20%-30% of patients show symptomatic cardiac or liver involvement. Cutaneous manifestations are extremely rare with only a few published cases. We report 2 additional cases of cutaneous LCDD without detectable systemic disease.