"He is always sick"

December 1, 2006

A 5-year-old boy arrives at the ED for management of sepsis and evaluation of "blast cells" on a peripheral blood smear. His guardian says that he is "always sick." What's causing this medical mystery?

DR. SCHOLER is a pediatrician in practice at Guilford Child Health, Inc., High Point, N.C. She completed her residency in pediatrics in2003 at UNC Hospitals, Chapel Hill, N.C.DR. BLATT is a professor of pediatrics and chief of the division of hematology-oncology and DR. HENDERSON is a professor in thedivision of pediatric infectious disease and immunology, at the University of North Carolina School of Medicine, Chapel Hill.DR. SIBERRY is an assistant professor of pediatrics in the divisions of general pediatric and adolescent medicine and pediatric infectiousdiseases at Johns Hopkins Hospital, Baltimore.The authors and section editor have nothing to disclose in regard to affiliations with , or financial interests in, any organization that mayhave an interest in any part of this article.

You're the resident on call one summer night at a tertiary care hospital, when a 5-year-old boy is transferred from a community hospital for further management of sepsis and evaluation of reported "blast cells" on a peripheral blood smear. Upon his arrival in the emergency department, the boy has a two-day history of fever, petechiae, cough, lethargy, and diminished appetite. There's a note in the chart that his right eye and cheek are swollen and that he's complaining of arthralgias of the lower extremities, bilaterally. You head down to see him.

The medical history is significant: polyarticular arthritis of unknown cause that was diagnosed when your new patient was 10 months old and congenital hypothyroidism diagnosed shortly after birth, for which he takes levothyroxine daily. His guardian (a maternal aunt, not either biologic parent) tells you that that the boy is "always sick," but she can document only one hospitalization, at 3 years old for pneumonia, which required a prolonged course of antibiotics.

The admission review of systems, you note, is negative for any recent sick contacts, headache, visual disturbances, nasal congestion, sore throat, chest or abdominal pain, vomiting, diarrhea, or neurologic complaints. He has no history of recent trauma to the swollen eye.

He is certainly sick today

You enter the ED and find an acutely ill child awaiting you. Your physical examination is worrisome-here is a pale, lethargic, irritable child. Rectal temperature is 35.7°C; blood pressure, 107/71 mm Hg; pulse, 133/min; respirations, 22/min; and oxygen saturation, 97% while breathing room air. You observe right periorbital swelling and erythema of the right cheek, without proptosis and with intact extraocular muscle function.

Other physical findings include decreased breath sounds at the base of both lungs; weak pulses in all extremities; clear heart sounds without murmurs, thrills, rubs, or gallops; delayed capillary refill (4 sec); a liver edge approximately 5 to 6 cm below the costal margin; a spleen palpable 3 to 4 cm below the costal margin; and diffuse petechiae.

So, you wonder, what is going on with this child? Highest on the list in your immediate differential diagnosis are infectious causes; you presume that he has sepsis with disseminated intravascular coagulation, pneumonia, and facial cellulitis. Immediately, you obtain specimens for culture of blood and urine, then administer an intravenous bolus of normal saline (20 cc/kg) and ceftriaxone as supportive treatment.

Admission laboratory tests show a white blood cell count of 10.7 X 103/μL; hemoglobin, 9 g/dL; hematocrit, 27%; and platelet count, of 22 X 103/μL. The WBC count differential shows an absolute neutrophil count of 2 X 103/μL neutrophils and 7.5 x 103/μL lymphocytes. A peripheral blood smear reveals atypical lymphocytes but no evidence of blasts-despite the report of the community hospital from which the boy was referred.

Levels of serum electrolytes and liver enzymes are within normal ranges. The alkaline phosphatase level is 54 U/L; uric acid, 2.3 mg/dL; albumin, 2.6 g/dL; prothrombin time, 14.6 sec; International Normalized Ratio (INR), 1.3; activated partial thromboplastin time, 35 seconds; fibrinogen, 96 g/L, lactate dehydrogenase, 1,037 IU/L; and D-dimer, 3.06.

A chest radiograph demonstrates pneumonia with infiltrates in the lower lobes bilaterally. You continue IV maintenance fluids and ceftriaxone; the patient is admitted to the pediatric hematology-oncology service for further evaluation and management.

The picture is confused

Several days pass; the boy responds well. Pneumonia, cellulitis, and petechiae resolve. Despite antibiotic therapy, however, the splenomegaly, thrombocytopenia, anemia, and joint pain persist and he develops a fever.