25 April 2012
We report a case of an 11-month-old girl who was referred to us for fever, difficult feeding with progressive weight loss and a painful ulcer on the ventral surface of the tongue. Her clinical history was characterised by a perinatal hypoxic-ischaemic brain injury. The intra-oral examination revealed an ulcerative lesions extending from the tip to the ventral surface of the tongue. It was ovoid, well circumscribed, with raised and indurated edges and with a yellowish fibrinous base (Fig. 1a,c – lower arrow). Biochemical analysis, immunological and genetic studies were normal; cultivation of the lesion revealed flora saprophyte. As neurological examination revealed a multifocal dystonia including abnormal movements of the oro-facial musculature that caused the impact of the tongue between the lower central incisors, the diagnosis of ‘late Riga-Fede disease’ (RFD) was considered. The electroencephalogram (Fig. 1b) showed bihemispheric slow frequency rhythms, while the brain magnetic resonance imaging showed a thinning of the corpus callosum (Fig. 1c, upper arrow). Fever was treated with paracetamol, while the treatment with carbamazepine improved her neurological impairment, which when associated to a dental conservative approach (use of a flat nipple to avoid the impact of the teeth against the tongue associated to the topical application of a chlorhexidine 0.5% and hyluronic acid-based gels), led to a clinical amelioration of the ulcer (Fig. 1d) with an improvement of feeding and a gradual gain of weight.
RFD is a rare, oral, ulcerative condition described by Antonio Riga, an Italian physician in 1881. The oral ulcer is characterized by continuous traumatic injuries produced by natal or neonatal teeth, usually lower incisors, resulting in tongue ulceration. This form is called ‘precocious or early RFD’, and appears before 6 months of age, a period in which the child is edentulous. However, a ‘late RFD’ appearing in 6 months of age or in older children is also described. It is not due to a precocious teeth eruption, but, as in our case, to neurological or developmental disorders in a child with normal chronology of dental eruption.[2, 3] Hence, this latter disorder may be the initial presentation of some serious underlying medical problems, as Lesch–Nyhan syndrome, familial dysautonomia and/or other neurological disorders as parasomnia, hereditary chin trembling and facio-mandibular myoclonus that may cause nocturnal tongue biting.
From a point of view of its clinical manifestation, the differential diagnosis of RFD includes granular cell tumour, myofibroma, eosinophilic granuloma and other traumatic ulcers. Malignancies (sarcoma and lymphoma) and infectious diseases (acquired/congenital syphilis, tuberculosis and ulcerative fungal infections) must also be ruled out.
Because the precocious extractions may have a negative impact on the dentoalveolar growth of the children, the treatment of choice of RFD should be conservative (as in our case), reserving the surgical approach, with the extraction of the teeth and subsequent application of a space maintainer, only in case of non-healing in conservative treatment.