What is the most appropriate next step for a pregnant patient with suspected pyelonephritis after positive urinalysis?

In cases of suspected pyelonephritis during pregnancy, the most appropriate next step is hospital admission for intravenous treatment. Pyelonephritis is a serious infection that can lead to significant complications for both mother and fetus if not treated aggressively.

Ceftriaxone is a broad-spectrum cephalosporin antibiotic that is considered safe for use during pregnancy and is effective against the organisms that typically cause pyelonephritis. The preference for intravenous administration in a hospitalized setting allows for close monitoring of the patient's condition and rapid therapeutic response, which is critical in managing this type of infection.

Outpatient therapies, such as oral nitrofurantoin or trimethoprim-sulfamethoxazole, may be suitable for uncomplicated urinary tract infections but are not ideal for pyelonephritis, especially in a pregnant patient. Such infections often require more aggressive treatment due to the risk of severe complications, including preterm labor, sepsis, and low birth weight.

Therefore, the choice of hospital admission for IV ceftriaxone is the most appropriate next step in ensuring the health and safety of both the pregnant patient and the developing fetus in the context of a suspected pyelonephritis diagnosis.