A case of skin hypopigmentation secondary to a corticosteroid injection.

Abstract: A 47-year-old African-American male presented complaining of Achilles tendon pain. The patient was treated for three weeks with a nonsteroidal anti-inflammatory agent with minimal pain relief. The tendon was subsequently injected with triamcinolone acetonide and five months later, the patient presented with an area of hypopigmentation around the injection site. The patient was diagnosed with hypopigmentation secondary to the steroid injection.

Key Words: corticosteroids, hypopigmentation, adverse effects

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The injection of acutely and chronically inflamed joints, soft tissue, and tendon sheaths are commonplace in primary care practices. Injectable steroids have been utilized for many years due to the ease of administration, profound efficacy of local therapy, and the significant reduction in side effects as compared with oral therapy. Commonly used steroids include triamcinolone, methylprednisolone, and dexamethasone with short- and long-acting formulations currently available. Steroids have numerous classical and well reported systemic side effects; however, one of the less common side effects includes dermatological reactions such as hypopigmentation. While the etiology of the reaction remains unknown, a limited number of case reports are documented in the literature of hypopigmentation secondary to a steroid injection. To our knowledge, there have been no documented reports of hypopigmentation resulting from a triamcinolone injection of the Achilles tendon.

Case Report

A 47-year-old African-American male presented with a 3-day history of Achilles tendon pain. His pain was an 8/10 and was constant without radiation. He reported that the pain was worse upon standing and his review of systems and neurologic examination were unremarkable. His physical examination revealed a pleasant man in no distress. Examination of his extremity revealed tenderness of the left Achilles tendon without swelling.

The patient was diagnosed with Achilles tendonitis. A nonsteroidal anti-inflammatory was prescribed for three weeks with minimal improvement in pain. At that point, the Achilles tendon was injected with triamcinolone acetonide 40 mg and the patient showed marked improvement in pain one week after the injection. The patient returned five months later with an area of approximately 3 cm X 1 1/2 cm of hypopigmentation of the left Achilles tendon which spread around the primary steroid injection site (Fig.). The diagnosis of hypopigmentation secondary to steroid injection was made at that time. Seven months after the injection, improvement in the skin tone was noted and the site had started to repigment.

Discussion

Injectable steroids differ in regard to relative potency, duration of action, and solubility. (1) Triamcinolone acetonide is considered an intermediate-acting steroid with a biologic half-life of 18 to 36 hours (2) and is available in suspension form, which provides an increased duration of action. (1) Injectable steroid solutions tend to be shorter acting due to more rapid physiologic clearance, but are less irritating and may have minimal side effects. (1) More potent, insoluble compounds may be preferred and may offer an improved effect in chronic conditions due to their prolonged action attributable to significantly reduced dissolution at the site of injection. (3)

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Adverse effects of injectable steroids include atrophy of the skin, irritation at the injection site, hypopigmentation, hyperpigmentation, alopecia, telangiectasia, striae, and acneiform eruptions. (3,4,5) Hypopigmentation has been documented in case reports as an adverse effect of steroid injections of the hand, (3) metatarsophalangeal joints of the foot, (6) the knees, thumb, sternum, and calf. (7) Several of these sites were injected to reduce the size of keloid structures. (7) Most reported cases occurred in African Americans. (3,7) In the documented cases, the hypopigmentation generally occurred several months after one or more steroid injections. (3,6,7) The hypopigmented area began to resolve without further treatment several months after the discontinuation of the steroid in the majority of cases. (3,6,7) One case reported an area of unresolved hypopigmentation one year after injection of the site. (7) The etiology of steroid-induced hypopigmentation remains unknown. It has been proposed that steroids may reduce the number or activity of melanocytes, (4,7) presumably by unintentional migration of the steroid in the proximity of the injection site or by improper injection technique. (7)

Conclusion

Hypopigmentation can be particularly problematic and embarrassing to individuals with dark skin; therefore, it is important to consider this effect when injecting an individual of a race where hypopigmentation may be a problem. Although most cases of hypopigmentation resolve, an instance of permanent discoloration has been reported. To minimize side effects such as hypopigmentation, it is recommended that shorter acting, soluble steroids such as methylprednisolone or hydrocortisone be used to inject soft tissues locally.

References

1. Carek PJ, Hunter MH. Joint and soft tissue injections in primary care. Clinics in Family Practice 2005;7:359-377.

2. Lacy CF, Armstrong LL, Goldman MP, et al. Lexi-Comp's Drug Information Handbook, 12th ed. Hudson, Lexi-comp Inc., 2004, pp 1457-1461.

3. Stapczynski JS. Localized depigmentation after steroid injection of a ganglion cyst on the hand. Ann Emerg Med 1991;20:807-809.

4. Goette DK, Odom RB. Adverse effects of corticosteroids. Cutis 1979;23: 477-487.

5. Wintroub BU, Stern R. Cutaneous drug reactions: pathogenesis and clinical classification. J Am Acad Dermatol 1985;13:167-179.

6. McCormack PC, Ledesdma GN, Vaillant JG. Linear hypopigmentation after intra-articular corticosteroid injection. Arch Dermatol 1984;120:708-709.

7. Friedman SJ, Butler DF, Pittelkow MR. Perilesional linear atrophy and hypopigmentation after intralesional corticosteroid therapy. Report of two cases and a review of the literature. J Am Acad Dermatol 1988;19:537-541.

Kennedy Okere, MD, and Melissa C. Jones, PharmD, BCPS 

From the Memorial Family Medicine Center, Savannah, GA.

Reprint requests to Melissa C. Jones, PharmD, BCPS, South University School of Pharmacy, 709 Mall Boulevard, Savannah, GA 31406. Email: [e-mail]

Accepted April 4, 2006.

RELATED ARTICLE: Key Points

* Hypopigmentation is an uncommon side effect of corticosteroid injections.

* The etiology of hypopigmentation secondary to corticosteroids is unknown; however, there are some proposed mechanisms.

* In most documented eases, the hypopigmented area began to repigment in less than one year after the steroid was discontinued.

* The risk of hypopigmentation can be minimized by using a short-acting, soluble corticosteroid solution when injecting areas of soft tissue.