Index of SuspicionCase 1 DiscussionCase 2 DiscussionCase 3 DiscussionCase 4 Discussion

Case 1 Presentation

A previously healthy 3-year-old girl presents with a 5-week history of an enlarged nodule involving the right frontal scalp area that began as a reddish-purple papule. There is no history of pain, redness, or drainage. She is afebrile and otherwise asymptomatic. However, she had experienced minor trauma 2 years ago when she accidentally struck her head on a table. Her grandmother describes her granddaughter's living conditions as “filthy,” and the girl often plays outside in the soil. Household animal contacts include frequent exposures to puppies and kittens.

Physical examination reveals a 2-cm raised mass in the right frontal region of the skull, with surrounding edema and mild tenderness. Radiographs (Fig. 1) show a right frontal lytic lesion that has a small central density, possibly reflecting a sequestrum. Head CT scan shows the lesion extending from the bone into the adjacent scalp. MRI suggests an eosinophilic granuloma or osteomyelitis without involvement of brain parenchyma. A bone scan reveals no involvement of any other sites. The girl's C-reactive protein value is 1 mg/dL (normal, <0.5 mg/dL) and ESR is 8 mm/hr (normal, <15 mm/hr). She undergoes biopsy of the skull, which reveals the diagnosis.

Case 2 Presentation

An 11-month-old previously healthy boy presents to an outlying ED with complaints of vomiting, diarrhea, and markedly decreased appetite for 24 hours. His temperature is 38.2°C, heart rate is 128 beats/min, respiratory rate is 42 breaths/min, blood pressure is 85/60 mm Hg, and oxygen saturation is 92% on room air. Physical examination reveals an infant who is “drowsy but not lethargic, and fussy with interventions.” His mucous membranes are dry and he produces no tears, but he has good pulses. Both tympanic membranes are red but …