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?
(Answer on next page)
Answer: A pediatric endocrine consult confirmed a diagnosis of nutritional (vitamin D-deficient) rickets.
It was the assessment of the child protection team that the child's small subarachnoid hemorrhage and orbital ecchymosis could be consistent with a fall from 5 feet onto a hard surface. The femur fracture also could have occurred during the fall and may have occurred with relative ease because of the child's rickets. This—combined with a possible borderline platelet count—was thought to explain the constellation of her injuries adequately.
The treatment plan for this patient included supplementation with ergocalciferol( (25-vitamin D) at high doses initially (40,000 to 50,000 IU over 24 hours), then 8000 IU daily for 8 to 12 weeks, followed by a standard multivitamin. Feeding with standard infant formula and additional calcium supplementation was also recommended.
The parents appeared appropriately concerned and more than willing to provide infant formula and vitamin supplementation to their daughter. Within 3 days, the infant's calcium and phosphorus levels had increased to 9.1 mg/dL and 3.0 mg/dL, respectively. The parents were also were willing to make the long drive back to the hospital for medical follow-up with the pediatric endocrinologist and to accept a referral to a local primary care physician. This follow-up was tracked carefully.
The family has been compliant. An x-ray film of the child's wrist taken 1 month after her initial hospitalization showed progressive healing of the rachitic changes. The parathyroid hormone level had dropped to 53 pg/mL, and calcium was stable at 10.3 mg/dL.
An excellent review of dietary rickets can be found in the January 2005 issue of Consultant for Pediatricians.1
The child in this case was somewhat unusual, in that she was fair-skinned and lived in an area with adequate sunshine year-round. Dietary rickets appears to be reemerging in exclusively breast-fed infants because of low amounts of vitamin D in breast milk.2
Rickets may be mistaken for abuse. It can also present as tetany and hypocalcemic seizures in childen in whom this disease was not previously suspected.3 This has prompted the American Academy of Pediatrics (AAP) to recommend vitamin D supplementation for all breast-fed infants.4
The many clinical variants of rickets are listed in the Table. A thoughtful, careful clinical and laboratory assessment is essential in making the correct diagnosis. In this case, the highly unusual dietary history was of critical diagnostic importance.
The parents were engaged in a discussion of the clinical findings in a supportive, nonjudgmental manner. This approach won their confidence and helped them understand the repercussions of their dietary practice on the child's health. If the parents had not been amenable to providing commercial formula and vitamin supplementation--or had failed to obtain the medical follow-up as advised--neglect would have been considered and appropriate child-protection agencies would have been notified. In this case, reporting to child-protection services was considered a "last" recourse, not the first.
This case also demonstrates the importance of the skeletal survey, which is considered mandatory in children younger than 2 years who have injuries that suggest abuse.5 The skeletal survey in this case was the key to diagnosing the child's nutritional problems and to providing treatment. In my experience, despite well-publicized AAP and American College of Radiology recommendations, skeletal surveys are often not requested for infants who present with isolated fractures or suspicious bruising. Skeletal surveys are not only used to assess additional abusive injuries but also are part of an overall diagnostic process that may uncover the "mimic" rather than the abuse.