Subtle-but-smouldering myocardial injury after immune checkpoint inhibitor treatment accompanied by amyloid deposits.

Although cardiac troponin is a highly specific biomarker for myocardial cell injury, it is important to recognize the pitfalls of this test in the diagnosis and management of immune checkpoint inhibitor (ICI) myocarditis. We describe the challenging case of an 81-year-old woman with persistently high troponin after undergoing immunotherapy with ipilimumab and nivolumab, and histological evidence of amyloid deposition in the myocardium. The patient received immunosuppressive treatments based on the magnitude of troponin changes because myocarditis was clinically suspected. However, histological examination revealed the deposition of transthyretin amyloid fibrils with only minimal T-lymphocyte infiltration and no myocyte necrosis, suggesting transthyretin cardiac amyloidosis rather than ICI myocarditis. This case highlights the importance of assessing other causes of persistently high troponin, and the necessity of incorporating comprehensive histological and immunohistochemical examinations of the endomyocardial biopsy, especially when cardiovascular magnetic resonance imaging is inconclusive.

Eosinophilic fasciitis induced by a game of drumming probably via type 2 innate immunity.

We report a case of eosinophilic fasciitis triggered by strenuous physical activity, which did not relapse during the follow-up period. We ascertained that interleukin-33 (IL-33) was released from the vascular endothelial cells after intense exercise, inducing type 2 innate lymphocytes (ILC2) and causing fasciitis. A healthy woman experienced itching on both limbs a few hours after a game of drumming. Her hand, knee joints, and legs gradually swelled up with groove signs along the superficial veins. White blood cell and eosinophil counts were significantly elevated. Magnetic resonance imaging revealed a high signal at the fascia on both lower limbs. Histopathological findings of the left lower limb tissue specimen showed edematous fascia with eosinophils. No relapse of eosinophilic fasciitis was observed after finishing treatment with prednisolone. Immunological staining for IL-4, IL-5, IL-33, tumor necrosis factor-α, and interferon-γ was performed on the fascial tissue. Both IL-4 and IL-5 were stained on the lymphocytes at the muscle and fascia levels; however, CD3 and CD4 were unstained in these cells, suggesting that those cells were ILC2. Tumor necrosis factor-α and interferon-γ were unstained. Vascular endothelial cells in the fascia strongly expressed IL-33. Eosinophilic fasciitis may be associated with type 2 immunity triggered by IL-33 in the current case.

Successful Treatment of Ulcerative-Type Pyoderma Gangrenosum with a Combination Therapy of Oral Prednisolone, Vacuum-Assisted Closure, and Skin Grafting.

Pyoderma gangrenosum (PG) is a relatively rare inflammatory skin disease that progressively causes necrotic ulceration mainly on the lower extremities and trunk. Systemic corticosteroid is considered a first-line treatment for PG as it facilitates wound healing; however, several cases where tumor necrosis factor-α inhibitors, adalimumab and infliximab, were administered showed good response. For intractable PG with a large ulcer or problematic epithelization, chemical or mechanical debridement of necrotic tissue in combination with skin grafting may be necessary to promote wound healing. Our report presents a case of intractable ulcerative PG requiring oral prednisolone and skin grafting. Although mechanical debridement was performed, granulation was poor; therefore, after the PG activity became quiescent, we utilized a vacuum-assisted closure (VAC) system to promote granulation and adaptation of the grafted skin. Although more cases are required for a definitive conclusion, the VAC system may be a choice for PG with large ulcers.