Mucocele_0912 Derm Dx
An 8-year-old boy presents with a lump in his inner lower lip that has been present for several weeks.
The patient denies pain. There has been no associated fever or other symptoms. The boy is otherwise well, is up to date on all his vaccinations and takes no medications. On physical exam, a soft, non-tender, rounded papule is noted within the mucosa of the lower lip.
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Mucoceles result from either obstruction or trauma to the minor salivary ducts, occurring most commonly in the inside of the lower lip. The most frequent etiology is trauma, for example from biting the lower lip.
Clinically, mucoceles appear as soft, round, sometimes bluish or translucent papules. When palpated they are fluctuant, tense and nontender. Any oral mucosal area with minor salivary glands has the potential to develop a mucocele including the ventral tongue, buccal mucosa and posterior hard palate. When incised or accidentally traumatized, a sticky straw-colored liquid is released; however, the sac usually refills after a brief interval.
Mucoceles most commonly occur when the mucous ducts of the minor salivary glands rupture with the subsequent spillage of mucus into the submucosa creating a cystic space. Mucoceles may also be due to dilation of a partially obstructed salivary gland, which creates a mucus-filled cystic structure that is termed “mucus retention cyst,” or “ranula,” when it occurs in the floor of the mouth.
Mucoceles occur most commonly in individuals younger than 30 years and affect males and females equally.
Clinical diagnosis is based on the presence of soft, painless and rounded swelling, which is typically located in the inner lower lip. Mucoceles can also be diagnosed histologically when biopsied or excised.
In contrast, a congenital epulis presents as a protuberant mass on the gum of the newborn. Focal epithelial hyperplasias present as multiple soft papules on the oral mucosa that may coalesce into plaques. It is caused by human papillomavirus types 13 and 32.
Pyogenic granulomas present as a friable, bright red, rapidly growing papules or nodules and may occur in the oral mucosa.
Mucocele treatment consists of surgical excision or marsupialization.
Adam Rees, MD, is a graduate of the University of California Los Angeles School of Medicine and a resident in the Department of Dermatology at Baylor College of Medicine in Houston.
- Bolognia J, Jorizzo JL, Rapini RP. “Chapter 71: Oral Disease.” Dermatology. St. Louis, Mo.: Mosby/Elsevier, 2008.
- James WD, Berger TG, Elston DM et al. ” Chapter 34: Disorders of the Mucous Membranes.” Andrews’ Diseases of the Skin: Clinical Dermatology. Philadelphia: Saunders Elsevier, 2006.
- Schachner L, Hansen RC. “Chapter 9: Mucous membrane disorders.” Pediatric Dermatology. New York: Churchill Livingstone, 1995.