THE CASE: A 5-month-old girl was brought to the emergency department (ED) 1 day after she had fallen from a countertop swing onto a tile floor. The child had been loosely buckled in the swing when the mother stepped into the next room. The mother heard a crash and the baby crying: when she came back into the room, the baby's 5-year-old sister was trying to disentangle her from the swing. The infant did not lose consciousness, was quickly comforted, and did not vomit. However, the mother noted that the baby's right thigh seemed tender and that a "black eye" was developing on the left lid. The family lived several hours from the hospital and decided to observe the baby during the night and make the trip to the ED the following morning.
Physical examination of the baby in the ED demonstrated normal growth and good development. Her weight was 6.1 kg and her height was 62 cm (both in the 25th percentile); her head circumference was 42 cm (50th percentile). The patient was alert, with a nonfocal neurologic examination. She had an obvious supraorbital ecchymosis (Figure 1).
She also had obvious swelling and tenderness both to palpation and to movement of her right thigh. X-ray films demonstrated a "buckle fracture" of the distal right femur (Figure 2). The radiologist also noted an irregularity of the right femoral metaphysis that could have been a "corner fracture." A CT scan revealed a small subarachnoid hemorrhage in the right frontal area (Figure 3). CT orbital cuts demonstrated a mass--presumably hemorrhage posterior to the right eye within the bony orbit (Figure 4).
A child-protection consultation was obtained, and a skeletal survey was requested. The survey revealed marked separation of the cranial sutures and generalized demineralization of the skull and long bones. The metaphyseal ends of the ribs appeared to be splayed. Rachitic changes were noted in the proximal humeri and the proximal and distal femurs, in the proximal and distal tibiae and fibulae, and in both radii and ulnae (Figures 5 and 6).
Additional details of the dietary history were obtained from the mother. The parents live in an isolated rural community. The mother's breast milk dried up when the infant was 3 weeks old. The mother was advised to feed her baby "natural products," and the child was fed combinations of carrot juice, almond milk, and raw cow's milk. A jar of carrot juice was on the child's bedside table.
Laboratory tests revealed a serum calcium level of 7.4 mg/dL (normal range, 8.7 to 9.8 mg/dL); ionized calcium, 0.96 mmol/L (normal, 1.22 to 1.48 mmol/L); phosphorus, 2.9 mg/dL (normal, 4.3 to 7.4 mg/dL); alkaline phosphatase, 1056 U/L (normal, 114 to 460 U/L); parathyroid hormone, 575 pg/mL (normal, 15 to 75 pg/mL); 1,25-dihydroxyvitamin D, undetectable. A complete blood cell count revealed a hematocrit of 32.3% and a hemoglobin level of 10.1 g/dL; the platelet count was low (130,000/µL). Both prothrombin time and partial thromboplastin time were normal.
Do the history and laboratory results rule out physical abuse?