Subcutaneous fat necrosis of the newborn and associated hypercalcemia: A systematic review of the literature

Abstract

Subcutaneous fat necrosis of the newborn is an uncommon disorder, and although usually benign, associated hypercalcemia can lead to complications such as failure to thrive and renal failure. Many sources suggest screening for hypercalcemia for 6 months following resolution of skin lesions, but little data are available to support this recommendation. This study examines existing published literature to better guide practitioners regarding screening evaluations of asymptomatic patients with subcutaneous fat necrosis. A systematic review of the literature was conducted using a PubMed English literature search. Data from case reports and case series were collected regarding the presence of hypercalcemia and associated complications, birth history, and age of onset/resolution of skin lesions and laboratory abnormalities. Approximately half (51%) of infants reported had hypercalcemia. Most (77%) developed detectable hypercalcemia within 30 days of skin lesion onset, and 95% developed detectable hypercalcemia within 60 days of skin lesion onset. Hypercalcemia was detected in only 4% of patients > 70 days following onset of skin lesions. Seventy-six percent had resolution of hypercalcemia within 4 weeks of detection. Hypercalcemia was more prevalent in full-term vs pre-term infants (P-value = 0.054), and higher birthweight was significantly associated with an increased risk of developing hypercalcemia (P-value = 0.022). Although gestational age trended toward significance, the only statistically significant clinical feature predicting the development of hypercalcemia was higher birthweight. Current recommendations for laboratory monitoring are not evidence-based, and this study provides interim data to guide practitioners until prospective, randomized controlled trials are conducted.

Subcutaneous fat necrosis of the newborn

“…Stefanko et al postulated that hypercalcaemia screening until 6 months of age was over-conservative, and recommended hypercalcaemia screening at diagnosis, and again at 30, 45 and 60 days post-resolution of skin lesions. They recommend rescreening if there are any concerns regarding hypercalcaemia within 6 months of resolution of skin lesions 1. Our data support the more conservative approach, as adopted by Del Pozzo-Magana, as detailed below 3…”

“…Hypercalcaemia resolved within 28 days in 54% (15/28) of cases. This is lower than in other reviews which found that 76% of hypercalcaemia resolved within 28 days 1. Stefanko et al postulated that hypercalcaemia screening until 6 months of age was over-conservative, and recommended hypercalcaemia screening at diagnosis, and again at 30, 45 and 60 days post-resolution of skin lesions.…”

“…It is unclear whether hypoglycaemia is a true risk factor, rather than an associated finding. Macrosomia appears to be an independent risk factor 1–4. In recent years, therapeutic hypothermia has become a more prevalent risk factor.…”

“…Fever has been reported in up to 57% of cases. Treatment is symptomatic, including medical treatment of hypercalcaemia and surgical removal of nodules 1 3 4…”

Use of Zoledronic Acid in a Neonate with Subcutaneous Fat Necrosis Complicated with Severe, Refractory Hypercalcemia

“…There is a lack of evidence coming from randomized controlled studies, as recently pointed out in a comprehensive review that included only case series and case reports. 8 Several studies have reported so far the use of bisphosphonate products to manage severe neonatal hypercalcemia. Use of pamidronate was reported by Samedi et al in two infants with severe hypercalcemia associated with SCFN following therapeutic hypothermia for hypoxic-ischemic encephalopathy.…”