Subcutaneous Fat Necrosis of the Newborn: A 20‐Year Retrospective Study

Abstract

Subcutaneous fat necrosis of the newborn (SFN) is a rare form of panniculitis that can be complicated by hypercalcemia and nephrocalcinosis. We conducted a 20-year retrospective cohort study of 30 patients to describe the clinical characteristics of SFN and the prevalence of hypercalcemia and other complications. Hypoxia and therapeutic hypothermia (TH) seem to play an important role in the development of SFN. Hypercalcemia developed in 63% of patients, three of whom developed nephrocalcinosis. There is a need for well-controlled prospective studies to determine the natural history, prevalence, and incidence of complications of SFN.

Hypercalcemic Disorders in Children

“…Similarly, macrophages represent an extrarenal site that can have substantial 1α‐hydroxylase activity. Sequestration of macrophages in granulomatous and inflammatory tissues (eg, sarcoidosis, tuberculosis, human immunodeficiency virus [HIV] immune reconstitution syndrome, leprosy, fungal granuloma including coccidiomycosis, cat scratch fever, Crohn's disease, CMV, histoplasmosis, and subcutaneous fat necrosis of the newborn) can cause dysregulated production of 1,25(OH) 2 D 3 , leading to hypercalcemia . Subcutaneous fat necrosis of the newborn (SFN) is an unusual form of lobular panniculitis that typically affects newborns born at term or postterm, often with a preceding history of birth trauma or birth asphyxia, and may occur from birth up until the first 6 weeks of life.…”

“…Subcutaneous fat necrosis of the newborn (SFN) is an unusual form of lobular panniculitis that typically affects newborns born at term or postterm, often with a preceding history of birth trauma or birth asphyxia, and may occur from birth up until the first 6 weeks of life. SFN may also be associated with hypothermia or therapeutic cooling, and is characterized by single or multiple erythematous violaceous plaques and nodules that can evolve into calcifications and tend to occur on the back, face, buttocks, and shoulders . It is associated with hypercalcemia that can be life‐threatening and the severity and duration of hypercalcemia are associated with the extent of the skin lesions .…”

“…Sequestration of macrophages in granulomatous and inflammatory tissues (eg, sarcoidosis, tuberculosis, human immunodeficiency virus [HIV] immune reconstitution syndrome, leprosy, fungal granuloma including coccidiomycosis, cat scratch fever, Crohn's disease, CMV, histoplasmosis, and subcutaneous fat necrosis of the newborn) can cause dysregulated production of 1,25(OH) 2 D 3 , leading to hypercalcemia. (30)(31)(32)(33)(34)(35)(36) Subcutaneous fat necrosis of the newborn (SFN) is an unusual form of lobular panniculitis that typically affects newborns born at term or postterm, often with a preceding history of birth trauma or birth asphyxia, and may occur from birth up until the first 6 weeks of life. SFN may also be associated with hypothermia or therapeutic cooling, and is characterized by single or multiple erythematous violaceous plaques and nodules that can evolve into calcifications and tend to occur on the back, face, buttocks, and shoulders.…”

“…(31,32) It is associated with hypercalcemia that can be life-threatening and the severity and duration of hypercalcemia are associated with the extent of the skin lesions. (31) It has been proposed that an insult on the immature fat cells, such as exposure to cold (eg, therapeutic hypothermia for hypoxia-ischemia encephalopathy or hypoperfusion), (31) may result in the development of necrosis and the development of a granulomatous infiltrate in the necrotic areas. In keeping with this, abundant levels of 1ahydroxylase have been found in affected tissues, which may lead to increased production of 1,25(OH) 2 D 3 with associated hypercalcemia as reported in other granulomatous disorders.…”

Image Gallery: Subcutaneous fat necrosis of the newborn

“…Subcutaneous fat necrosis of the newborn (SCFN) was diagnosed. SCFN is a rare panniculitis following perinatal asphyxia or therapeutic hypothermia, and resolves spontaneously within several months . SCFN is occasionally complicated by metabolic alterations including hypercalcaemia .…”