Pediatric emergency medicine trisk 0934 0934

hepatitis, splenomegaly, and neurologic involvement Characteristic laboratory findings include anemia, thrombocytopenia, and elevated liver enzymes, as well as extremely elevated ferritin levels and hypertriglyceridemia Immune and cytokine studies, as well as genetic testing and bone marrow studies showing hemophagocytosis are used to establish the diagnosis Finally, rare causes of systemic adenopathy include lipid storage diseases, such as Gaucher disease and Niemann–Pick disease, which can cause diffuse adenopathy and are almost always associated with hepatosplenomegaly Bone marrow biopsy, showing lipidladen histiocytes, is diagnostic LIFE-THREATENING LYMPHADENOPATHY In rare instances, lymphadenopathy can lead to a life-threatening condition In children and adolescents affected by Hodgkin or non-Hodgkin lymphoma or metastatic neuroblastoma, bulky or rapidly enlarging mediastinal lymph nodes can cause compression of the superior vena cava (SVC) or the tracheobronchial tree In SVC syndrome, lymph nodes that encircle the vena cava enlarge and cause obstruction to central venous blood flow This obstruction leads to clinical manifestations including dilated chest and neck veins, facial swelling and plethora, and dyspnea Progression may lead to headaches, confusion, and altered mental status as well as progressive respiratory distress Children with bulky adenopathy of the mediastinal or paratracheal nodes may present solely with respiratory symptoms, including stridor or wheezing, caused by compression of the trachea or bronchi by enlarged lymph nodes Emergency physicians who take care of children with suspected lymphoma must be aware of the acute risk of airway obstruction that may be exacerbated by changes in position (lying flat) or with sedation or anesthesia In addition, when treating children with SVC syndrome, physicians must be careful to administer all intravenous therapy in the lower extremities, as poor circulation in the upper extremities and torso because of venous obstruction results in poor drug distribution and places the patient at increased risk of thrombus formation EVALUATION AND DECISION The pediatric emergency physician who evaluates a child with lymphadenopathy is faced with an extensive differential diagnosis However, a targeted history and thorough physical examination can help focus evaluation of the patient and will often lead to the correct diagnosis Historical data that need to be obtained include the time of onset, rate of growth, and presence of other symptoms Local symptoms suggestive of infection are particularly relevant, including fever, conjunctivitis, otitis, pharyngitis, gingivostomatitis, or cellulitis, as these may correlate with acute regional lymphadenopathy In well-appearing children, recent illnesses must be considered, particularly because reactive adenopathy may persist for to weeks after the resolution of a viral illness During evaluation, it is important to note the presence of “red flag” constitutional symptoms, including prolonged fevers,