Diagnosis

Geographic tongue is clinically identified as an 'erythema, atrophic area circumscribed by a yellowish-white line with lesions that often change their location and shape over a span of a few minutes and primarily affect the dorsum of the tongue' (Picciani 2017). These investigators identified that the diagnosis of GT is most commonly based on clinical features and histopathological analysis is rarely performed.

Etiology

Gonzalez-Alvarez et al (2019) through meta-analysis concluded that geographic tongue (GT) was a manifestation of psoriasis. These authors through literature search (Gonzalez-Alvarez 2018) identified GT to additionally be associated  with allergies and anxiety with the presence of caries associated.

Picciani et al (2017) identified difference in clinical presentation of GT between patents with and without psoriasis. These investigators studied 96 patients with GT and identified in non-psoriatic patients the lesion was more often symptomatic and had a 'thick halo'. In contrast, psoriatic patients were frequently asymptomatic and had more severe lesions with greater loss of papillae.

Classification: As per Picciani et al. (2021), a classification scale was identified as ranging from absent (0) to severe (4) through "GTASI calculation" based on a severity score of 0 to 4 evaluating erythema and white halo

Management: usually not needed - observation reasonable option - a host of therapeutic options generalized for oral mucoscal disease: https://medicine.uiowa.edu/iowaprotocols/therapeutic-agents-oral-mucosal-disease-treatment-strategies

References

González-Álvarez L, García-Martín JM, García-Pola MJ. Association between geographic tongue and psoriasis: A systematic review and meta-analyses.J Oral Pathol Med. 2019 May;48(5):365-372. doi: 10.1111/jop.12840. Epub 2019 Feb 27. Review.

González-Álvarez L1, García-Pola MJ2, Garcia-Martin JM1.Geographic tongue: Predisposing factors, diagnosis and treatment. A systematic review.Rev Clin Esp. 2018 Dec;218(9):481-488. doi: 10.1016/j.rce.2018.05.006. Epub 2018 Jun 11.

Picciani B1, Santos VC1, Teixeira-Souza T1, Izahias LM1, Curty Á1, Avelleira JC2, Azulay D2, Pinto J3, Carneiro S4, Dias E1.Investigation of the clinical features of geographic tongue: unveiling its relationship with oral psoriasis.Int J Dermatol. 2017 Apr;56(4):421-427. doi: 10.1111/ijd.13460. Epub 2017 Feb 10.

Picciani BLS, Santos LR, Amin TN, Rocha Santos JD, Carneiro S, Neffa Pinto JM, Regazzi Avelleira JC, Azulay DR, de Sousa Gonzaga HF, Luiz RR, Dziedzic A. Applicability of the Geographic Tongue Area and Severity Index among Healthcare Professionals: A Cross-Sectional Clinical Validation of a Newly Developed Geographic Tongue Scoring System. J Clin Med. 2021 Nov 24;10(23):5493. doi: 10.3390/jcm10235493. PMID: 34884195; PMCID: PMC8658609.