Necrose adiposa do recém-nascido: a propósito de dois casos clínicos

Abstract

Subcutaneous fat necrosis of the newborn is an uncommon disorder occurring during the prenatal stage. Generally occurring in full-term neonates or during the first four weeks after a traumatic delivery, the disorder is characterized by the appearance of hard subcutaneous nodules or plaques on the trunk, buttocks or thighs. It is normally a benign and transient condition, although it may be complicated by hypocalcemia, which requires close monitoring until skin lesions are cured. The authors describe two cases of subcutaneous fat necrosis of the newborn, one occurring in a full-term neonate and the other in a premature newborn, both related to traumatic delivery and fetal distress. Keywords: Dystocia; Infant, newborn, diseases; Fat necrosis; Hypocalcemia. Resumo:A necrose adiposa subcutânea do recém-nascido é uma paniculite rara do período neonatal. Surge, geralmente, em recém-nascidos de termo ou pós-termo, nas primeiras 4 semanas de vida, e em associação com trauma obstétrico. Caracteriza-se pelo aparecimento de placas ou nódulos subcutâneos duros, localizados ao tronco, nádegas ou coxas. O seu curso é, geralmente, benigno e autolimitado, embora possa acompanhar-se de hipercalcemia, o que obriga a uma vigilância periódica até à resolução das lesões cutâneas. Os autores descrevem 2 casos de necrose adiposa subcutânea do recém-nascido, um num recém-nascido de termo, outro num prematuro, ambos associados a partos traumáticos e a sofrimento fetal.

Subcutaneous fat necrosis of the newborn: clinical manifestations in two cases

“…The newborns affected are born at term or post-term, with normal general health, though there have been cases of pre-term newborns being affected. 1,2 It generally occurs within the first six weeks of life, and no cases of lesions present at birth were found in the literature consulted. 1 …”

Subcutaneous fat necrosis of the newborn: clinical and histopathological correlation

“…The etiology of SFNN is unknown, but maternal factors (Rh incompatibility, preeclampsia, cocaine use, and calcium channel blockers) and fetal factors (whole-body cooling, perinatal asphyxia, and sepsis) appear to be involved. 2 It is postulated that neonatal asphyxia leads to shunting of blood from the skin and fat tissue to nobler structures like the heart and brain, leading in turn to fat necrosis. 3 Thrombocytopenia usually occurs simultaneously with the lesions and can result from platelets being sequestered by the nodules.…”

“…The regression of the lesions is usually associated with an increase in serum calcium levels, especially due to the increase in the release of prostaglandins, release of calcium from the necrotic tissue, and the greater release of 1,25-di-hydroxyvitamin D3 by the granulomata. 2 , 4 This alteration is highly important, since failure to implement prompt therapy can lead to severe complications such as nephrolithiasis, nephrocalcinosis, and acute renal injury. 5 …”