ALBERT C.YANMD SAMIR SSHAHMD
The first association between heel sticks to draw blood in the neonatal period and the development of calcified nodules of the heel was made by O’Doherty1 and has since been fairly well-recognized in the neonatology community. Most reports of this entity have described it in association with high-risk neonates receiving multiple heel sticks in the nursery. However, more recently, Leung2 and Rho et al3 reported cases occurring following a single heel stick in healthy neonates.
Lesions may be multiple or solitary, white or yellowish verrucous papules or nodules, which are firm and often tender.1- 10 Typically, the lesions appear 4 to 12 months after birth4- 7 as multiple tiny specks that gradually enlarge and either persist or spontaneously extrude through the epidermis. Spontaneous resolution may occur within 18 to 30 months,4,5,7,8 yet recurrence following removal with curettage has been reported.6 Although previously thought to be largely asymptomatic, a protracted course with discomfort or tenderness may ensue.3,6
Plain films, if obtained, reveal opacity in the soft tissue.5,6 Cases in which laboratory studies were obtained have reported normal serum calcium and phosphate levels.3,4,7,8 As in our case, pathologic specimens characteristically show a cystic structure with irregular calcification, surrounded by fibrous connective tissue and a patchy mononuclear infiltrate without an epithelial lining or evidence of polarizable material.
The pathogenesis of these lesions likely involves dystrophic calcification following local tissue injury. Dystrophic calcification is defined as the abnormal deposition of insoluble calcium salts in dead or degenerated cutaneous tissues in the absence of abnormal serum calcium or phosphate concentrations. In addition to heel sticks, dystrophic calcinosis cutis has also been reported in scarring caused by burns, trauma, and surgery.9 Injured tissue releases alkaline phosphatase, resulting in an elevation in the local pH and subsequent precipitation of calcium salts.10 As suggested by Williamson and Holt,6 repeated trauma to existing small lesions from footwear may promote further dystrophic calcification and enlargement of the lesions. However, it has also been suggested that these lesions may result from secondarily calcified epidermal inclusion cysts introduced by the heel sticks.4,7 Although most authors describe the absence of an epithelial lining, which would argue against this etiology, one case did report the presence of an epithelial lining surrounding foci of calcification and fragments of keratin.7
For recurrent or symptomatic lesions, surgical excision or curettage may be warranted. As no abnormalities of calcium or phosphate have been reported to date in association with such lesions, further laboratory investigations do not appear to be warranted, although plain x-rays may help in making the diagnosis. This case describes a more chronic course, presenting as a symptomatic lesion later in childhood. In the case presented herein, the patient did receive 8 total heel sticks during her prolonged postnatal hospitalization.
Correspondence: Amy E. Gilliam, MD, Department of Dermatology, University of California, San Francisco, 1701 Divisadero St, 3rd Floor, San Francisco, CA 94143-0316 (email@example.com).
Accepted for Publication: October 31, 2005.
Acknowledgment: The clinical photograph was provided by Kelly M. Cordoro, MD, University of Virginia Health System, Charlottesville.
Picture of the Month—Diagnosis. Arch Pediatr Adolesc Med. 2006;160(6):646. doi:10.1001/archpedi.160.6.645-b