The seasonal variation in allergic rhinitis and its correlation with outdoor allergens in Kuwait.

BACKGROUND: Allergic rhinitis (AR) is the most common allergic problem in Kuwait. Most of the patients who have either AR or asthma are referred to the Al-Rashed Allergy Center. OBJECTIVE: To determine if there is a seasonal variation in AR in Kuwait and to correlate it with the daily pollen count. METHODS: Information about the new patients referred to the center over a 5-year study period (1996-2000) was extracted from the center's records. The daily pollen count in Kuwait city was obtained from the Air Biology Laboratory. RESULTS: There was a significant seasonal variation with a bimodal increase in the number of patients with AR referred to the center. The main peak in the number of patients occurred in September-October, and there was a smaller peak in April-May. The mean number +/- SD of new patients per month over the 5-year period varied from 87 +/- 32 for December to 367 +/- 104 for September. Similarly, the average daily pollen count varied from 3.7 +/- 1.0 pollens per mm3 in January to 124 +/- 92 in October. There was high correlation between the number of new AR patients and the average total pollen count (Pearson correlation, r=0.77, p<0.001), as well as with Chenopodiaceae and Amaranthaceae (weed) pollens (r=0.75, p<0.001), while there was no correlation between the number of new patients and either tree or grass pollens. CONCLUSION: Seasonal AR occurs during two periods in Kuwait, i.e. September-October and April-May, with September-October being the main season. The rise in AR during late summer in Kuwait is mainly associated with the pollination of Chenopodiaceae species.

Th1 and Th2 cytokine profiles in recurrent aborters with successful pregnancy and with subsequent abortions.

BACKGROUND: This study compared Th1-Th2 cytokine profiles in a subgroup of recurrent aborters who had an abortion with those in a subgroup of recurrent aborters who had a successful pregnancy. METHODS: Fifty-four women with a history of at least three normal pregnancies, 24 women with a history of recurrent spontaneous abortion (RSA) followed by abortion (RSA-->A) and 39 women with a history of RSA followed by normal pregnancy (RSA-->N) were studied. Blood samples and placentas were obtained at the time of delivery or abortion; peripheral blood mononuclear cells were stimulated separately with phytohaemagglutinin and with autologous placental cells, and the secreted cytokines estimated. RESULTS: Peripheral blood mononuclear cells from the RSA-->N subgroup secreted higher concentrations of Th1-type cytokines as compared with normal pregnant women, indicating a higher Th1 bias in these women. However, women in the RSA-->N subgroup had significantly higher concentrations of Th2 cytokines as compared with women in the RSA-->A subgroup. A comparison of Th1:Th2 cytokine ratios indicated a higher Th2 bias in RSA-->N women as compared with RSA-->A women. CONCLUSIONS: We conclude that abortion-prone women who proceed to have successful pregnancy are more Th2-biased than abortion-prone women who abort, and that recurrent aborters who undergo spontaneous abortion have a stronger Th1 bias than aborters who have normal pregnancy.

Cytokine patterns in maternal blood after premature rupture of membranes.

OBJECTIVE: To compare two types of cytokines, type 1, which activate cell-mediated reactions and are important in cytotoxic and delayed-type hypersensitivity reactions, and type 2, which encourage vigorous antibody production and are commonly found in association with humoral immune responses, in blood of women with premature rupture of membranes (PROM). METHODS: Forty-four women with histories of at least three successful pregnancies and who currently delivered normally served as controls. The PROM group consisted of 30 women with spontaneous rupture of fetal membranes at term. Peripheral blood mononuclear cells were stimulated separately with a mitogen, placental cells, and a trophoblast antigen extract, and the supernatants examined for type 1 and type 2 cytokines. RESULTS: Mitogen-stimulated blood cells produced significantly higher levels of type 1 cytokines in PROM women than in normal controls. Higher levels of the type 1 cytokine interferon-gamma were produced by PROM samples stimulated with autologous placental cells and with trophoblast antigens. Ratios of type 1 to type 2 cytokines were higher in PROM compared with normal pregnancy, and in some cases as much as 25-fold higher. CONCLUSION: Women in the PROM group had a stronger type 1 reactivity whereas normal women were more predisposed to type 2 immunity; thus, PROM appears to be associated with a maternal type 1 bias.