Omphalitis
Omphalitis refers to an acute inflammation caused by bacterial invasion and proliferation in the umbilical stump. Staphylococcus aureus is the most common pathogen, followed by Escherichia coli, Pseudomonas aeruginosa, and hemolytic streptococci, among others. In mild cases, there is redness and swelling around the umbilical ring and surrounding skin, accompanied by a small amount of purulent discharge. Severe cases present with marked redness, swelling, and induration of the umbilical ring and surrounding area, with large amounts of purulent discharge. The infection may spread to surrounding skin or tissues, leading to complications such as abdominal wall cellulitis, subcutaneous necrosis, peritonitis, or sepsis. Colonization of the umbilicus by organisms such as Staphylococcus aureus, Staphylococcus epidermidis, E. coli, and streptococci is common in healthy neonates. A positive culture of local secretions does not necessarily indicate an infection. The presence of inflammation in the umbilical area should be carefully differentiated. Mild cases are managed with topical cleaning using 3% hydrogen peroxide or povidone-iodine solution two to three times daily. Cases with local spread or systemic symptoms are treated with intravenous antibiotics. Abscesses, if present, may require incision and drainage.
Umbilical Hernia
Umbilical hernia occurs due to incomplete closure or weakness of the umbilical ring, allowing abdominal organs to protrude through the ring beneath the skin. The hernia sac consists of peritoneum along with subcutaneous tissue and skin. The contents of the sac typically include the omentum and small intestine, which are usually not adherent to the sac wall. The size of the hernia sac varies, with diameters typically around 1 cm but sometimes exceeding 3–4 cm. Umbilical hernias are more common in low-birth-weight infants. The hernia becomes prominent when the infant cries or strains and can be manually reduced when the infant is calm. Strangulation rarely occurs. With increasing abdominal muscle strength during the first year of life, most hernias decrease in size, narrow, and close spontaneously, resulting in a good prognosis. Surgical repair may be considered for large hernias or those that do not resolve by the age of two years.
Umbilical Granuloma
Umbilical granuloma refers to a small overgrowth of granulation tissue that forms at the umbilical stump site due to irritation from foreign substances, repeated friction, or infection. The surface of the granuloma is moist and may exhibit some mucous or mucopurulent exudate. Cleaning the granuloma with povidone-iodine several times a day achieves a good prognosis in most cases. Persistent granulomas, which appear gray-red with a surface that produces bloody discharge, may require treatment with 10% silver nitrate for cauterization or excision using sterilized scissors.