sinusitis, orbital cellulitis, or dental abscess Often these patients will present with a history of dental or facial pain, sinus congestion, erythema, or fever A history of environmental exposure should lead to the diagnosis of other common causes of localized swelling including sunburn, frostbite, and plant-induced dermatitis (poison ivy) Although rarely seen, pit viper envenomation may cause rapid onset of painful swelling at the site of injury (see Chapter 90 Environmental Emergencies, Radiological Emergencies, Bites and Stings ) Occasionally, an infant will present with unexplained, localized swelling of an extremity that has been present since birth In this situation, the possibility of an injury secondary to birth trauma should be explored Less commonly, congenital lymphedema (Milroy disease), Turner syndrome (bilateral leg edema), and Noonan syndrome (pedal edema) should be considered Meige disease (lymphedema praecox) is a hereditary disorder that also results in lymphedema, but patients will present later in childhood or around puberty, usually with swelling of the feet or lower legs FIGURE 25.1 Edema in children GI, gastrointestinal; SIADH, syndrome of inappropriate secretion of antidiuretic hormone