Congenital Mucocele of the Tongue in a Neonate

Introduction

Congenital mucocele of tongue is a very rare condition in which the infant presents with symptoms of airway obstruction, feeding difficulty, and failure to thrive. Antenatal diagnosis of these lesions is important as they may cause breathing difficulties at birth and interferes with feeding.¹

Congenital mucoele has incidence of 1.82 in 100000 births.¹ The occurrence of retention cyst in the oral cavity is common in general population and its incidence was estimated as 2.4 in 1,000 population, frequently reported in the second decade of life.^2,3Congenital mucocele involving the ventral surface of the tongue in neonates is very rare, with sporadic cases being reported in the world,^4,5 accounting to 2-8% of oral mucoceles.⁶

Congenital mucocele of the tongue could remain completely asymptomatic or persist till adolescence with subsequent regression of the symptoms.¹ A suspected case of congenital mucocele of tongue should be followed up with routine investigations along with imaging studies to come to a conclusive diagnosis and management.^1,4,5 Here, we report a rare case of symptomatic congenital mucocele of the tongue in a neonate.

Case Presentation

A 5-day male neonate presented with a history of swelling on the ventral aspect of tongue since birth with associated difficulty in breast feeding (Figure 1). The neonate was not able to close the mouth and had continuous protrusion of the tongue. There was no history of respiratory difficulty or cyanosis at birth. The child had a normal full-term vaginal delivery with immediate cry after birth. Antenatal history of mother was uneventful. Antenatal ultrasonography was normal. Oral examination revealed 3.5 × 2.5 cm tense swelling along the ventral surface of the tongue causing persistent mouth opening. Surface of the swelling was smooth, non-tender, circumscribed, non-ulcerated with cystic consistency. Swelling was bluish in colour and brightly transilluminant. The dorsum of the tongue was normal in texture. The base of tongue could not be visualized. On ultrasonography, the swelling showed hypoechoic lesion with normal doppler flow without any vascularity.

Neonate underwent en block excision of the cystic swelling, along with removal of entire cyst wall (Figure 2). Jelly like fluid was noticed after cyst opening. The defect was closed with interrupted sutures (Figure 3). Nasogastric feed was started after six hours and oral breast feed started after 24 hours of surgery. Postoperative period was uneventful. Child was discharged on third post-operative day. The follow-up was scheduled at 1 week, 1 month and 3 months and no evidence of recurrence was observed. Histopathological examination showed cystic lesion with islets of salivary glands in the wall suggestive of mucocele (Figure 4).

Discussion

Congenital mucocele of tongue is a rather rare occurrence with very few cases reported in the literature.^1,2 Most of the cases of tongue retention cysts (mucocele) are asymptomatic and would regress with age. There are two major hypotheses to explain the pathogenesis, which consider the cyst as a consequence of either ductal obstruction of the mucus glands or an embryological malformation.⁴

Majority of the mucoceles of oral cavity occur in the lower lip.⁵ Occasionally they may be seen on the ventral surface of the tongue where they involve glands of Blandine -Nuhn.^2,6 They are submucous glands located within the ventral part of the muscles of the tongue, and are anteriorly placed close to the midline with their ducts opening on the inferior surface. Mucoceles are usually found following trauma and are seen in the younger age group.^4,6 But in our case, it was a congenital variety of mucocele involving the tongue of a new-born. Congenital mucoceles on the ventral aspect/lingual surface of the tongue before one year of age are very uncommon.⁴

As an effort to collect data, we performed a comprehensive search of the literature using PubMed/Medline electronic database, and all the published literature on congenital mucocele involving the ventral aspect of the tongue in early infancy were reviewed (Table 1).^7,8,9,10

According to the data collected, four cases have been published with age of presentation less than one year. One case was diagnosed prenatally at 39 weeks of gestation. Two cases had complaints of difficulty in breastfeeding and respiratory distress, which was also observed in the present reported case. The fourth case reported in the literature was of a 4-month old infant with breathing and feeding difficulties. On histopathological examination, all the published cases had mucous retention cyst type of entity.^7,8,9,10 All cases exhibited swelling on the ventral aspect/lingual surface of the tongue, which was the presentation in our case also. 

Congenital mucocele of tongue should be considered in differential diagnosis in new-born with tongue swelling presenting with feeding difficulty, stridor, respiratory distress. Definitive management is with marsupialization or complete excision of the cyst wall.

Conflicts of Interest

Nil