Woman With Blue-Gray Palate and Nail Beds

OUTCOME FOR THE CASE PATIENT
A biopsy of the roof of the patient’s mouth confirmed that the palatal hyperpigmentation was caused by her antimalarial medications. Since the patient displayed no evidence of active lupus skin lesions and laboratory results indicated that her SLE was inactive, one of the drugs, quinacrine, was discontinued.

The patient was referred for an ophthalmologic evaluation. No evidence of retinal toxicity was found.

Follow-up evaluations at two months and six months revealed no significant improvement in the discoloration of the patient’s oral mucosa or nail beds. At the six-month visit, her dosage of hydroxychloroquine was reevaluated.

The patient’s hydroxychloroquine dosage was determined based on 7.3 mg/kg/d. In the case of an overweight patient, especially one of shorter-than-average stature, hydroxychloroquine dosing should be based on ideal body weight to minimize the risk for overdosage; in general, a maximum dosage of 6.5 mg/kg/d is recommended.^8,9 As a result, the patient’s dosage was decreased to 300 mg/d.

At her nine-month follow-up evaluation, the discoloration to the patient’s oral mucosa had faded but had not resolved completely (see Figure 3). No significant change was noted in the subungual discoloration. The patient had experienced no exacerbations of lupus-related symptoms since her medication adjustments.

CONCLUSION
Although this patient’s hyperpigmentation was benign, staying alert to this potential adverse effect of antimalarial drugs is important in making a diagnosis. As with many skin lesions, if the clinical evaluation does not provide a clear cause, a biopsy may be needed. For anyone taking antimalarial drugs, regular ophthalmologic evaluations are recommended to facilitate early detection of the rare adverse effect of retinal toxicity. Nevertheless, with careful monitoring, antimalarial drugs are safe and effective for the treatment of inflammatory conditions such as SLE and rheumatoid arthritis.

REFERENCES
1. Kleinegger CL, Hammond HL, Finkelstein MW. Oral mucosal hyperpigmentation secondary to antimalarial drug therapy. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2000;90(2):189-194.

2. Gondak R-O, da Silva-Jorge R, Jorge J, et al. Oral pigmented lesions: clinicopathologic features and review of the literature. Med Oral Pathol Oral Cir Bucal. 2012;17(6):e919-e924.

3. Lerman MA, Karimbux N, Guze KA, Woo SB. Pigmentation of the hard palate. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2009;
107:8-12.

4. Kalampalikis A, Goetze S, Elsner P. Isolated hyperpigmentation of the oral mucosa due to hydroxychloroquine. J Dtsch Dermatol Ges. 2012; 10(12):921-922.

5. de Andrade BA, Fonseca FP, Pires FR, et al. Hard palate hyperpigmentation secondary to chronic chloroquine therapy: report of five cases.
J Cutan Pathol. 2013;40(9):833-838.

6. Tuffanelli D, Abraham RK, Dubois EI. Pigmentation from antimalarial therapy: its possible relationship to the ocular lesions. Arch Derm. 1963; 88:419-426.

7. Melikoglu MA, Melikoglu M, Gurbuz U, et al. Hydroxychloroquine-induced hyperpigmentation: a case report. J Clin Pharm Ther. 2008; 33(6):699-701.

8. Marmor MF, Kellner U, Lai YY, et al; American Academy of Ophthalmology. Revised recommendations on screening for chloroquine and hydroxychloroquine retinopathy. Ophthalmology. 2011;118(2):
415-422.

9. Screening for hydroxychloroquine retinopathy. Position statement, American College of Rheumatology. www.rheumatology.org/Practice/Clinical/Position/Position_Statements/. Accessed July 17, 2014.