Dermatologist in private practice in Arizona
GREGORY WALLACE—Series Editor
Hospitalist at Cincinnati Children’s Hospital and Medical Center in Cincinnati and a staff physician at the Northern Kentucky Advocacy Center in Bellevue, Ky.
Because the history and presentation were concerning for physical abuse, the child abuse team was consulted in the ED.
Studies to include in a workup for suspected child abuse. A skeletal survey and head CT were obtained; neither showed evidence of abuse. Pediatric ophthalmology was consulted: no retinal hemorrhages were identified. Note that a skeletal survey, head CT scan, and pediatric ophthalmology consultation are all justified in any child younger than 24 months who has unexplained injuries.1
Laboratory studies included in a workup for unexplained bruising. Laboratory studies in the ED revealed a white blood cell count of 17,100/μL; hemoglobin level, 8.1 g/dL; hematocrit, 26.3%; reticulocyte count, 1.9% (normal, 0.5% to 1.9%); and platelet count, 541,000/μL. Prothrombin time (PT) was greater than 120 seconds (normal, 10.1 to 13.6 seconds); fibrinogen level was 565 mg/dL (normal, 200 to 400 mg/dL); thrombin time was 12.3 seconds (normal, 14.2 to 21.3 seconds); and partial thromboplastin time (PTT) was greater than 120 seconds (normal, 26.4 to 35.9 seconds). Results of urinalysis were normal. γ-Glutamyltransferase level was 86 U/L (normal, 6 to 19 U/L); alkaline phosphatase level was 511 U/L (normal, 145 to 320 U/L); and total protein level was 5.3 g/dL (normal, 5.4 to 7.0 g/dL). Total iron-binding capacity was 188 μg/dL (normal, 215 to 450 μg/dL). Results of other liver and renal function tests were normal for the child’s age. A chest radiograph showed opacity in the upper lobe of the right lung compatible with atelectasis, although pneumonia could not be definitively excluded.
The child was admitted to the hospital for further diagnostic testing and treatment. Hematology was consulted for workup of the elevated PT, PTT, and fibrinogen level. Treatment with tobramycin and cefipime was started for presumed pneumonia until further workup could be completed. On the second day of his hospital stay, after initial screening tests and storage of additional blood, the child was treated with vitamin K.
Differential diagnosis of abnormal clotting in an infant. Any malabsorptive disorder that affects vitamin K absorption could have been the cause of this patient’s symptoms and laboratory abnormalities. The complete differential diagnosis included celiac disease, α1-antitrypsin deficiency, hepatitis, abetalipoproteinemia, warfarin exposure, and biliary atresia.2 Factors II, VII, IX, and X are vitamin K–dependent, but the liver produces virtually all clotting factors. Here, however, other liver diseases did not need to be considered because of the high fibrinogen level and normal liver function test results. Vitamin K absorption can also be affected by altered bacterial colonization resulting from antibiotic use. Young children are particularly sensitive to vitamin K malabsorption disorders because very little vitamin K is transferred across the placenta and the reserves are thus very small. The most plentiful source of vitamin K in children’s diets is commercial formula; breast milk is a very poor source. The absorption of vitamin K is dependent on intact biliary and pancreatic function. A small amount will be synthesized by normal gut flora.
On the basis of the history and laboratory test results, hemorrhagic disease of the neonate and CF figured prominently in this patient’s differential diagnosis.
Outcome of this case. Results of sweat chloride testing were positive, with an initial value of 84 mEq/L (normal, less than 60 mEq/L) and a second value of 92 mEq/L on hospital day 2. Serum levels of fat-soluble vitamins were obtained: the vitamin A level was less than 140 μg/dL (normal, 140 to 520 μg/dL), and the vitamin D level was 5 pg/mL (normal, 9 to 46 pg/mL). Results of lung/bronchoscopy cultures were returned on day 3 and were positive for β-lactamase–producing Haemophilus influenzae. Coagulation factors had all normalized within 48 hours, after 2 doses of vitamin K.
|•||In an effort not to make unfounded allegations and yet protect innocent children, physicians dealing with abuse and neglect should do broad screening tests in an attempt to exclude rare underlying organic diseases. Thus, a coagulation evaluation is warranted in any child with significant, unexplained bruising.|
|•||Although it happens infrequently, cystic fibrosis (CF) can present as a bleeding disorder. Thus, while a rare occurrence, CF can mimic child abuse.3-5|