Erythematous plaque on an infant’s cheek

Figure 1

Figure 2

The case

A healthy, afebrile, 12-month-old girl presents for evaluation with an asymptomatic nodule on her left cheek that has been present for 3 weeks (Figure 1). She was initially seen by her pediatrician, diagnosed with cellulitis, and prescribed an oral antibiotic, which was not administered by her parents.

Diagnosis: Cold panniculitis

Etiology/Epidemiology

Cold panniculitis is a phenomenon that occurs primarily in infants and young children due to a higher proportion of saturated fats in subcutaneous fat compared with older children and adults.¹ Saturated fats become solid with cold exposure at a relatively higher temperature than unsaturated fats, leading to the potential for fat crystallization and adipocyte damage with short exposures to cold.

Development of cold panniculitis after exposure to popsicles and cold environments has been reported particularly in young children.^2,3 Additionally, there have been reports of cold panniculitis as a complication of ice pack application to the face and as a vagal maneuver to treat supraventricular tachycardia in newborns.^2,4,5 Red, indurated plaques typically develop 24 to 72 hours after exposure, frequently occurring on the cheeks or chin due to a higher amount of subcutaneous fat in these areas.

Whereas a clinical diagnosis can be made by physical examination in the setting of an appropriate history, histopathology is confirmatory but usually not necessary. A lobular panniculitis with a lymphocytic and histiocytic inflammatory infiltrate is present at the junction of the dermis and subcutaneous fat.^1,2

Differential diagnosis

Included in the differential diagnosis of cold panniculitis are the other panniculitides seen in the pediatric population. These include subcutaneous fat necrosis of the newborn (SCFN), poststeroid panniculitis, and sclerema neonatorum.⁶ Subcutaneous fat necrosis of the newborn appears in full-term infants and may be associated with perinatal complications. Erythematous to violaceous indurated plaques or subcutaneous nodules appear within days to weeks of birth. Much of the body can be involved, but the anterior trunk is classically spared.⁶ Although benign, SCFN should be differentiated from cold panniculitis due to the potential for metabolic derangements, specifically hypercalcemia. The possibility of such complications necessitates clinical monitoring of patients with SCFN.

Post-steroid panniculitis characteristically presents in children who are on high doses of systemic corticosteroids followed by rapid withdrawal.⁶ Erythematous subcutaneous nodules develop within several days of steroid cessation, most commonly on the cheeks, again attributed to the high concentration of fat in this area as occurs with steroid therapy. The lesions are typically asymptomatic, but they can ulcerate and scar.

In the absence of a characteristic history for cold panniculitis, punch biopsy can be performed to support the diagnosis and rule out other conditions. Subcutaneous fat necrosis of the newborn is characterized by a radial pattern of needle-shaped crystals on histology.² Unlike cold panniculitis wherein infiltrates are limited to the upper subcutis, inflammation in SCFN involves the entire subcutaneous fat layer. Post-steroid panniculitis can appear identical to SCFN on biopsy but is easily distinguished with clinical correlation of high dose steroid use.

Sclerema neonatorum is a panniculitis most commonly seen in premature infants with infection or heart disease. Diffuse woody induration starts on the buttocks and thighs, with rapid extension to include other areas of the body. Feeding and respiration can be impaired if involvement is extensive enough to limit movement. Despite the ill appearance of the infant, histology may reveal only mild changes with little to no inflammation.⁶ Infectious cellulitis may also be considered in the differential diagnosis in the setting of a febrile and ill-appearing infant.

Management

No treatment is required for cold panniculitis. In the setting of an appropriate history and characteristic morphology, the patient can be monitored for improvement. The lesions typically progress from red to purple in color, with gradual improvement of induration. Complete resolution is expected in a period of weeks to months.

Patient outcome

On examination, the child was playful and afebrile. Upon further questioning, mother reported that the child lived in Alaska and spent time outside when at daycare.

At the time of this patient’s evaluation, 3 weeks after onset of the rash, the mother reported that the child’s lesion was spontaneously improving. Examination revealed a well-demarcated purple to red plaque, with greatly reduced erythema compared with the initial lesion (Figure 2). The mother was reassured of the benign nature of cold panniculitis and the expectation for full resolution. Ongoing protection from extreme cold exposure was recommended.

References:

1. Quesada-Cortes A, Campos-Munoz L, Diaz-Diaz RM, Casado-Jimenez M. Cold panniculitis. Dermatol Clin. 2008;26(4):485-489, vii.

2. Bolotin D, Duffy KL, Petronic-Rosic V, Rhee CJ, Myers PJ, Stein SL. Cold panniculitis following ice therapy for cardiac arrhythmia. Pediatr Dermatol. 2011;28(2):192-194.

3. Bournas VG, Eilbert W. Infant with facial lesions. Ann Emerg Med. 2011;58(2):216-221.

4. Markus JR, de Carvalho VO, Abagge KT, Percicotte L. Ice age: a case of cold panniculitis. Arch Dis Child Fetal Neonatal Ed. 2011;96(3):F200.

5. Ter Poorten JC, Hebert AA, Ilkiw R. Cold panniculitis in a neonate. J Am Acad Dermatol. 1995;33(2 Pt 2):383-385.

6. Polcari IC, Stein SL. Panniculitis in childhood. Dermatol Ther. 2010;23(4):356-367.