physical examination, 548 , 550 by genitourinary symptoms, 548 by GI symptoms, 548 life-threatening causes, 550 t in neonates, 552 by neurologic symptoms, 548 in older children, 553 –554 in older infants, 552 –553 regurgitation and, 549 t signs and symptoms associated with, 550 t symptomatic relief of, 554 Von Willebrand disease, 166 , 168 , 797 –798 Vulvar bleeding, 533 –534 Vulvar inflammation, 533 Vulvar lacerations, 533 Vulvitis, 384 t Vulvovaginitis, 384 t, 533 –534 W Waardenburg syndrome, 222 , 465 Warts, 635 –636 Weakness approaches to acute onset, 563 f subacute, indolent, or chronic, 564 f sudden onset of severe, 562 f causes, 559 t common, 560 t life-threatening, 557 t definition, 556 differential diagnosis, 556 –561 , 557 t evaluation and decision, 561 –565 pathophysiology, 556 Weight loss acute, 566 assessment of, 566 causes, 570 t