A 2-month-old with fever and cough has a WBC of 14,000/mm3 and a normal chest radiograph. What is an appropriate next step?

A 2-month-old with fever and cough has a WBC of 14,000/mm3 and a normal chest radiograph. What is an appropriate next step?

• A. Admitting the infant to the hospital for LP and IV antibiotics.
• B. Performing a catheterized urinalysis to screen for leukocytes and nitrites.
• C. Obtaining a blood culture, erythrocyte sedimentation rate, and C-reactive protein.
• D. Prescribing empiric, broad-spectrum antibiotics with close follow-up.

Answer: (B)

In febrile infants this young, a urinary tract infection is a common and important potential source of fever. The best next step is to obtain a catheterized urinalysis to screen for evidence of a UTI, such as leukocytes and nitrites. A catheterized sample provides a reliable result in infants, helping you decide whether a UA/urine culture is needed and whether antibiotics are warranted. The normal chest radiograph makes pneumonia less likely, so empiric antibiotic coverage for pneumonia isn’t indicated at this moment. Urgent invasive testing like a lumbar puncture is not automatically required unless there are signs suggesting meningitis (ill appearance, poor feeding, neck stiffness, etc.). Blood tests (ESR/CRP) are less decisive here and don’t directly identify the source as efficiently as a urinalysis does in this age group. If the UA is positive, you’d pursue urine culture and treat accordingly; if negative, you’d continue evaluation for other causes of fever.

In febrile infants this young, a urinary tract infection is a common and important potential source of fever. The best next step is to obtain a catheterized urinalysis to screen for evidence of a UTI, such as leukocytes and nitrites. A catheterized sample provides a reliable result in infants, helping you decide whether a UA/urine culture is needed and whether antibiotics are warranted.

The normal chest radiograph makes pneumonia less likely, so empiric antibiotic coverage for pneumonia isn’t indicated at this moment. Urgent invasive testing like a lumbar puncture is not automatically required unless there are signs suggesting meningitis (ill appearance, poor feeding, neck stiffness, etc.). Blood tests (ESR/CRP) are less decisive here and don’t directly identify the source as efficiently as a urinalysis does in this age group. If the UA is positive, you’d pursue urine culture and treat accordingly; if negative, you’d continue evaluation for other causes of fever.