HLA-Cw⊛0602 and HIV-associated psoriasis

Abstract

The aetiopathogenesis of psoriasis is unknown, but genetic and environmental factors may be involved. Psoriasis may not be one disease but a cutaneous inflammatory reaction pattern consequent upon several different independent or related stimuli in susceptible individuals. There are controversial issues regarding the immunological basis of psoriasis and the role of CD4 vs. CD8 T lymphocytes. Psoriasis has been associated with HLA-Cw6 and Cw7 by serology and specifically with HLA-Cw*0602 by polymerase chain reaction (PCR) typing. Psoriasis is probably no more common in HIV infection than in the general population; however, it may appear for the first time or pre-existing psoriasis may worsen and be difficult to treat in HIV disease. We have investigated the prevalence of HLA-C alleles, in the specific clinical context of HIV infection complicated by type 1 psoriasis, in a case control study of 14 men with HIV disease and type 1 psoriasis and 147 HIV-infected patients without psoriasis. Typing was performed using PCR with sequence-specific amplification primers. Eleven of 14 patients (79%) with psoriasis carried the HLA-Cw*0602 allele compared with 24.5% of those without psoriasis (odds ratio = 11.31; 95% confidence limits 2. 73 to 65.36; P = 0.0001). Two patients without the HLA-Cw*0602 allele carried instead the closely related Cw*0401/3 allele. The results confirm the previously reported association between the HLA-Cw*0602 allele and type 1 psoriasis, and suggest that the association with HLA-Cw*0602 is stronger in HIV-associated psoriasis although this trend needs to be supported by a larger sample. The immunodysregulation resulting from HIV infection may trigger psoriasis in those genetically predisposed by the Cw*0602 allele. As CD8 T cells recognize antigens in the context of class I major histocompatibility complex, the identification of an HLA class I association in HIV-associated psoriasis strengthens the argument for an important role for CD8 + T lymphocytes in the immunopathogenesis of psoriasis. Investigations of the pathogenesis of psoriasis should take account of clinical and other subtypes already identified.

Regressão de psoríase em paciente HIV-positivo após terapia anti-retroviral

“…Geralmente, as formas clínicas são mais graves, 9-11 e até mesmo desfigurantes, 6 com complicações secundárias 9,11 ou exacerbação da doença prévia. 12,13 O surgimento tardio da doença sem história familiar ou fatores de risco, como no doente analisado, impõe a investigação dessa infecção. 12 Duas formas clínicas principais podem ser encontradas: 1) psoríase gutata ou longas placas, sendo às vezes observadas as formas gutata e vulgar no mesmo paciente; 2) dermatite psoriasiforme difusa, em geral associada com queratodermia palmoplantar, que pode evoluir para doença generalizada, 3 forma em que o paciente deste caso melhor se enquadra.…”

“…4 É demonstrada associação da psoríase com HLA-CW6 e CW7 especialmente HLA-CW0602, sendo esta última mais freqüente em psoríase associada ao HIV, embora novos estudos sejam necessários. 13 O tratamento desses pacientes torna-se complexo e delicado. A resposta ao tratamento tópico pode ser pobre, 14 e alguns medicamentos devem ser evitados, seja porque são imunossupressores, 3 seja pela reação cruzada que podem provocar.…”

“…Usually, the clinical forms are more serious [9][10][11] and even disfiguring, 6 with secondary complications 9,11 or exacerbation of prior disease. 12,13 Such tardive appearance of the disease without familial history or risk factors, as in the patient described here, necessitates investigation for this infec-…”

“…4 Association of psoriasis is demonstrated with HLA-CW6 and CW7, especially HLA-CW0602, the latter being more frequent in psoriasis associated to HIV, although further studies are necessary. 13 Treatment of these patients is a complex and delicate task. The response to topical treatment can be poor 14 and certain medicines should be avoided, either because they are immunosuppressant, 3 or can provoke a cross reaction.…”

Paradoxical Exacerbation of Psoriasis in AIDS: Proposed Explanations Including the Potential Roles of Substance P and Gram-negative Bacteria

“…[13] As CD8 T cells recognise antigen in the context of class I major histocompatibility complex (MHC), the identification of a human leucocyte antigen (HLA) class I association in HIV-associated psoriasis strengthens the argument for an important role for CD8 T lymphocytes in the immunopathogenesis of psoriasis. [14] CD4 T cells may be activated early in HIV infection, but over time there is a marked increase in the CD8 T cell population as the CD4 cells are lysed by HIV. [15] Therefore, it has been reasoned [15] that HIV-induced T-cell imbalances may explain the afore-mentioned paradox.…”