Title:A Case of Doxycycline-induced Melanin in the Gingiva Tissue: Case Report
Volume: 18
Issue: 3
Author(s): Gustavo Henrique Apolinário Vieira, Aurigena Antunes de Araújo*, Rebeca Sá Leitão de Freitas, Lélia Batista de Souza, Ciro Dantas Soares, Lilian Karine Cardoso Guimarães de Carvalho, Samuel Batista Borges, Bruno Cesár de Vasconcelos Gurgel, Euler Maciel Dantas and Delane Maria Rêgo
Affiliation:
- Department of Biophysics and
Pharmacology, Post-Graduation Program Public Health/Post Graduation Program in Pharmaceutical Science, UFRN,
Natal, RN, Brazil
Keywords:
Doxycycline, periodontal tissue, melanin, dopamine, oxidative stress, DOPA.
Abstract:
Background: Gingival pigmentation is a discoloration of the gingiva due to a variety of
lesions and conditions associated with several endogenous and exogenous etiologic features.
Objective: The purpose of this study is to describe a report of gingival pigmentation in a patient
who used doxycycline.
Case Report: A 21-year-old Caucasian female was under dermatological treatment and antibiotic
therapy with doxycycline 100 mg (one time a day) for 90 days. She presented brown pigmentation
at the gingival margin on the facial surfaces of the upper and lower anterior incisors and premolars.
The patient was evaluated by immunohistochemical (S-100, Melan-A, and HMB-45) and histopathologic
analyses, and clinical history. Blood levels of malondialdehyde (MDA), glutathione
(GSH), and superoxide dismutase (SOD) were analyzed by UV/Vis spectroscopy. The adrenaline,
noradrenaline, and dopamine in blood were analyzed by high-performance liquid chromatography
(HPLC); dehidroepiandrosterone (DHEA) in serum by radioimmunoassay; and luteinizing hormone
(LH) and 25-Hydroxyvitamin D by chemiluminescence. Hematoxylin-eosin stained sections
revealed keratinocytes with pigment compatible with melanin. The Fontana-Masson staining was
positive in melanophages and in some basal keratinocytes. S-100, Melan A and HMB-45 were confirmed
as positive markers of melanocytic differentiation in gingival tissue. We observed a significant
increase in malondialdehyde (p˂0.05) and a decrease in superoxide dismutase levels (p˂0.05).
The dopamine value was found to be 15 pg/ml (reference value ≤ 10 pg/ml).
Conclusion: The use of doxycycline is associated with an increase in oxidative stress and of dopamine
with melanin pigments in the gingival tissue. This case report showed a cause-effect relationship
between exposure to doxycycline and pigmentation of the marginal gingiva.
