CORRECT DIAGNOSIS:
Lichen Planus Pigmentosus-Inversus
DISCUSSION:
Lichen Planus Pigmentosus-Inversus (LPP) is a rare clinical variant of lichen planus that presents as slate gray, brownish-black, or brown macules, papules, patches, or reticulated hyperpigmentation primarily found on sun exposed areas of the face and neck and flexural folds. Lichen Planus Pigmentosus (LPP) was first described in 1974 by Bhutani et al.1 in Indian patients as a pigmentary disorder similar to erythema dyschromicum perstans (EDP), or ashy dermatosis. The cause of LPP is currently unknown. It has been strongly suggested that lichen planus may be associated with hepatitis C virus (HCV). In a 2009 study, Al-Mutairi et al.3 evaluated thirty-three LPP patients in Kuwait. Of the patients, twenty (60%) were seropositive for HCV with significantly higher liver enzymes (AST and ALT). Since LPP is considered to be in the spectrum of lichenoid disorders, it is not surprising that this study supports a possible association between LPP and HCV. Therefore, when a diagnosis of LPP is suspected or confirmed, conservative laboratory workup may include serological testing for HCV. Lichen planus has been associated with type IV hypersensitivity, which may also play a role in LPP. This should be taken into consideration when developing a plan of treatment.
TREATMENT:
There is no specific standard treatment for LPP. Topical steroids, keratolytics, prednisone, griseofulvin, and chloroquine have been used with inconsistent results. Tacrolimus ointment showed promising results in one study, with an improvement of seven out of thirteen patients (53.8%) with LPP3.
REFERENCES:
Bhutani, L. K., Bedi, T. R., Pandhi, R. K., & Nayak, N. C. (1974). Lichen planus pigmentosus. Dermatologica, 149, 43-50. https://doi.org/10.1159/000250877
Pock, L., Jelinkova, L., Drjik, L., Abrhamova, S., Vojtechovska, S., Sezemska, D., Borodacova, I., & Hercogova, J. (2001). Lichen planus pigmentosus-inversus. Journal of the European Academy of Dermatology and Venereology, 15(5), 452-454. https://doi.org/10.1046/j.1468-3083.2001.00355.x [PMID: 11555477]
Al-Mutairi, N., & El-Khalawany, M. (2009). Clinicopathological characteristics of lichen planus pigmentosus and its response to tacrolimus ointment: An open label, non-randomized, prospective study. Journal of the European Academy of Dermatology and Venereology. Advance online publication. https://doi.org/10.1111/j.1468-3083.2009.03349.x
Vega, M. E., Waxtein, L., Arenas, R., Hojyo, T., & Dominguez-Soto, L. (1992). Ashy dermatosis and lichen planus pigmentosus: A clinicopathologic study of 31 cases. International Journal of Dermatology, 31(2), 90-94. https://doi.org/10.1111/j.1365-4362.1992.tb02289.x [PMID: 1576062]
Lichen planus pigmentosus-inversus: A case report. (2010). Journal of the American Academy of Dermatology, 62(3), Supplement 1. https://doi.org/10.1016/j.jaad.2009.11.930
Kashima, A., Tajiri, A., Yamashita, A., Asada, Y., & Setoyama, M. (2007). Two Japanese cases of lichen planus pigmentosus-inversus. International Journal of Dermatology, 46(7), 740-742. https://doi.org/10.1111/j.1365-4632.2007.03119.x [PMID: 17617270]
Cho, S., & Whang, K. K. (1997). Lichen planus pigmentosus presenting in zosteriform pattern. Journal of Dermatology, 24(3), 193-197. https://doi.org/10.1111/j.1346-8138.1997.tb02829.x [PMID: 9158788]
Chuang, T. Y., Stitle, L., Brashear, R., & Lewis, C. (1999). Hepatitis C virus and lichen planus: A case-control study of 340 patients. Journal of the American Academy of Dermatology, 41(5 Pt 1), 787-789. https://doi.org/10.1016/S0190-9622(99)70051-5 [PMID: 10545582]
Shengyuan, L., Songpo, Y., Wen, W., Wenjing, T., Haitao, Z., & Binyou, W. (2009). Hepatitis C virus and lichen planus: A reciprocal association determined by a meta-analysis. Archives of Dermatology, 145(9), 1040-1047. https://doi.org/10.1001/archdermatol.2009.177 [PMID: 19755330]
Bigby, M. (2009). The relationship between lichen planus and hepatitis C clarified. Archives of Dermatology, 145(9), 1048-1050. https://doi.org/10.1001/archdermatol.2009.177 [PMID: 19755331]
