Non-Neoplastic Dermatopathology

5.11 C ALCIPHYLAXIS VS MONCKEBERG MEDIAL CALCIFIC SCLEROSIS

Calciphylaxis

Monckeberg Medial Calcific Sclerosis

Age

Adults between ages of 50 and 70 years. Typically involves buttocks, thighs, and abdomen. Multifactorial mechanisms resulting in calcification of the media of small arterioles and capillaries. Obstruction of blood flow leads to thrombus formation, vascular occlusion, ischemia, and ulceration. Elevation in calcium/phosphate product and increased parathyroid hormone levels are seen in many patients. Painful, indurated, dusky plaques, livedo, or purpura. Lesions rapidly progress to ulcers with eschar. Highly associated with chronic renal disease and dialysis, but nonuremic cases do occur. 1. Epidermal ischemic necrosis with or without ulceration (Fig. 5.11.1) . 2. Mural calcification of small arterioles and capillaries in subcutaneous adipose tissue (Figs. 5.11.3 and 5.11.4) . 3. Intravascular thrombi and fibrointimal hyperplasia with erythrocyte extravasation (Figs. 5.11.2 and 5.11.3) . Von Kossa stain to confirm presence of vascular calcification in cases with subtle findings. Wound care, pain management, and antibiotics for secondary infection. Sodium thiosulfate, hyperbaric oxygen, bisphosphonates, and parathyroidectomy have also been used for management. Poor prognosis with considerable morbidity due to pain and chronic ulcerations. High mortality rate secondary to infection and sepsis.

Older adults, rare before 50 years of age.

Location

Extremities primarily involved.

Etiology

Exact mechanism is unknown but postulated to be due to stimulation of migratory adventitial myofibroblasts that acquire an osteoblastic phenotype secondary to the elaboration of osteopontin by vascular smooth muscle cells. Generally an incidental and asymptomatic condition. It is highly associated with aging, diabetes mellitus, and chronic kidney disease. Radiographic images of involved distal extremities produce a characteristic “railroad track” pattern. 1. Epidermis and dermis are generally normal and without ischemic changes. 2. Calcification in the tunica media of small and medium-sized arteries of the deep dermis and subcutaneous tissues (Fig. 5.11.5) . 3. Lumina of vessels are patent and the

Presentation

Histology

calcification is not associated with thrombus formation or erythrocyte extravasation (Fig. 5.11.6) .

Special studies

None needed. Calcifications are typically large and, therefore, von Kossa stain is not necessary.

Treatment

No treatment is indicated.

Although Monckeberg medial calcific sclerosis does not cause vascular occlusion, as in atherosclerosis, it has been shown to be a risk factor for cardiovascular and peripheral vascular disease. Copyright © Wolters Kluwer, Inc. Unauthorized reproduction of the content is prohibited. 2023

Prognosis

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