A 10-month-old infant has a two-inch soft bulge under the umbilicus that appeared after coughing. The infant does not cry when you palpate it. What is the most likely diagnosis?

• A. Diaphragmatic rupture
• B. Tumor
• C. Ascites
• D. Hernia

Answer: (D)

An umbilical hernia occurs when a weakness at the umbilical ring allows abdominal contents to protrude, and in infants the bulge commonly enlarges with events that increase intra‑abdominal pressure, such as crying or coughing. The scenario—an infant with a soft two‑inch bulge under the umbilicus that appears after coughing and is not tender when palpated—fits this pattern: a reducible, nonpainful protrusion at the umbilicus from a patent ring.

This fits better than the other possibilities. A diaphragmatic rupture would usually present with breathing difficulties or distress rather than a localized umbilical bulge. A tumor would generally be a more solid, fixed mass not specifically tied to episodes of coughing or crying. Ascites causes diffuse abdominal distention and fluid signs rather than a focal umbilical protrusion.

Most umbilical hernias in infants close on their own by about 3 to 4 years of age, so management is typically observation unless there are signs of incarceration (pain, vomiting, tenderness, irreducibility) or delayed closure.