Umbilical granuloma is the most common umbilical abnormality in newborn children or neonates, causing inflammation and drainage. It may appear in the first few weeks of newborn infants during the healing process of the umbilical cord due to an umbilical mass. It is the overgrowth of the umbilical tissue. It develops in about 1 out of 500 newborns. With appropriate treatment, it is expected to heal in 1~2 weeks.
Causes
Following umbilical cord clamping during delivery, the umbilicus base will spontaneously separate within 7-15 days. With routine cord care and proper hygienic conditions, the remaining umbilical base will heal and new skin tissue will form. In some instances, a mass of tissue, or granuloma, will form at the base.
Umbilical granulomas occur after umbilical cord removal when the remaining ring of the umbilicus undergoes incomplete wound healing and there is excessive healing tissue, also known as granulation tissue.
Delayed cord separation, mild infections and hygienic conditions are all factors which may contribute to the incidence of umbilical granuloma. Although the exact cause of umbilical granulomas is unknown, it is hypothesized that inflammation of the remaining umbilical stump drives skin cell division, resulting in a tissue mass, rather than proper healing at the site.
Histophysiology
An umbilical granuloma is a physiological response which surpasses the normal processes of skin restoration following umbilical cord clamping. Once the skin lesion is formed, there is an excess of fibroblast production. These fibroblasts, or connective tissue cells, are responsible for the production of collagen and additional fibers, resulting in the excess tissue mass found in the granuloma. Additional histological studies reveal an increase of cell division of vascular endothelial cells. These cells line our blood vessels and are further responsible for the growth and development of tissue and the formation of new blood vessels within the granuloma.
Pathophysiology
Inflammatory saprophytic microorganisms, involved with decomposition, may delay the healing process, and can lead to overproduction of fibroblasts that are involved in normal skin restoration. These microorganisms can interfere with the skin’s normal flora, and lead to increased pathogenic inflammation that leads to delayed epithelialization and the formation of granulomas with excessive blood vessels, fibroblasts, and mucus.
Signs and symptoms
Umbilical granulomas appear as round, pink lumps found at the base of the umbilicus after the removal of the umbilical cord. It appears small, pink/red, and moist due to cord separation. They are usually 1-10 mm in size, however grow in size if they are not treated. Umbilical granulomas are also painless since they do not contain nerve fibers. In some cases, they may contain an odorless discharge, or may be covered in a clear mucus. The surrounding skin of the infant's umbilicus site will appear normal.
Umbilical granulomas can become entry points for infectious agents. Symptoms such as edema, redness around the umbilical site, pain or discomfort when the area is touched, accompanied by a fever and purulent discharge, may indicate sepsis or a serious infection at the umbilicus site.
Diagnosis
Umbilical granuloma can be diagnosed from physical examination. If there is a discharge around the navel and the granulation tissue is large enough to be visible with the open eye, umbilical granuloma is the first to be suspected. Open eye inspection and/or dermoscopy is commonly used to recognize the granular tissue at the site. If the granuloma is not visible with the open eye, gentle pressure on the surrounding site or a surgical tweezer can be used to expose the small granuloma hidden within the umbilical pit. An otoscope may also be used by physicians in order to expose a small, sessile granuloma. Other additional tests are usually not required, but if continued, ultrasonography (US) can be used for initial diagnosis of umbilical lesions.
Treatment
Topical
Although there is no singular method of treatment for umbilical granulomas, some treatment options available include common salt, silver nitrate, corticosteroids, and cleaning with alcohol. Home care following treatments include gentle cleaning the navel area with soap and sterile water, followed by open exposure of the belly button to air.
Silver nitrate
Silver nitrate is the most common treatment and practiced worldwide. Neonatology textbooks suggest silver nitrate as a first-line treatment option. The application of silver nitrate to granulomas was first noted in early 1800s as a cauterizing agent.