Total IgE, mosquito saliva specific IgE and CD4+ count in HIV-infected patients with and without pruritic papular eruptions

Pruritic Papular Eruption (PPE) is a skin disorders found in HIV infected patients. However, the exact etiology of PPE is not documented. It has been suggested that PPE might result from arthropod bites. The aim of this study was to investigate those factors in the HIV patient contributing to the occurrence of PPE, including specific IgE against mosquito saliva allergens, total IgE, CD4 cell counts and their associations. Specific IgE against saliva allergens of Cx. quinquefasciatus mosquito was measured in 25 HIV patients with PPE and in 60 HIV without PPE by a time-resolved fluorescence immunoassay (TRIFA). The total IgE levels and CD4cell counts were also determined. Among the HIV patients with PPE, 84% (21/25) had CD4 cell counts less than 200 cells/μl in contrast to 30% (18/60) of the HIV without PPE patients. These differences were statistically significant (p =0.0005, χ2 test). The total IgE scores for the HIV patients with PPE were significantly higher than for those without PPE. A comparison of the mean arbitrary scores of the specific IgE in HIV patients, with and without PPE, was non-significant (p = 0.152). However, 44% (11/25) of the HIV patients with PPE had an arbitrary score above the mean score of mosquito bite allergic subjects, as compared to only 3.3% (2/60) of HIV patients without PPE. It may be concluded that the etiology of PPE in the HIV patient may be heterogeneous or multi-causal with allergic responses to the mosquito saliva allergen being only partially responsible.