ABSTRACT
Several studies have shown that decreased IFN γ or increased IL 4 secretion by Tcells are associated with allergy and these can predict the development of atopic diseases. We compared the production of IL 4 and IFN γ in atopic Thai children with appropriate controls. Twenty five atopic patients and twenty four non-atopic subjects were enrolled. Production of IFN γ and IL 4 by peripheral blood mononuclear leukocytes was measured under stimulating conditions (phorbol myristate acetate). The atopic group comprised 6 atopic asthmatics and 19 allergic rhinitis patients. The results showed no significant difference in the IFN γ/ IL 4 ratio between atopic asthmatics, and allergic rhinitis patients and controls. However, the difference between asthmatics and controls was larger than between the other groups. In this study, a nonsignificant trend of overproduction of IL 4 compared with IFN γ is shown only in asthmatic children as compared to those with rhinitis and controls.
ABSTRACT
Rheumatoid factor (RF) is one of the criteria used for diagnosis of rheumatoid arthritis (RA). The method that has been used in our laboratory service for many years is latex agglutination assay that gives semi-quantitative results. We are going to change from this method to nephelometry that gives continuous results. The cut-off point of RF by nephelometry, comparison of these 2 methods and the 4 supplying companies were determined. Serum samples were collected from 70 patients with RA, 22 patients with various collagen diseases and 150 blood donors or normal old people. RF values by nephelometry and 4 commercial latex agglutination assays, that were latex Alexon, Shield diagnostics, Biosyste, and Behring diagnostics, were determned and compared. The results showed that the cut-off point of RF by nephelometry was 14 IU/ml and the sensitivity and the specificity was 81% and 95% respectively. The sensitivity and the specificty of latex agglutination assays by 4 companies were 76% and 94%, 68% and 97%, 62% and 98% and 64% and 98% respectively. We concluded that nephelometry gave higher sensitivity than latex agglutination asssay and Latex Alexon had the highest sensitivity when comparing among the 4 companies.
ABSTRACT
The fluorescent treponemal antibody absorption test used with fractionated serum (FTA-ABS 19s IgM test) was evaluated as a test for congenital syphilis. From 1994 to 1995, 32 high-risk infants of mothers with untreated or inadequately treated syphilis and eight adults with primary or secondary syphilis were studied. The FTA-ABS 19s IgM was positive in 6 of 13 symptomatic babies (46 percent) with was a better rate than that given by the older method (38 percent), but only one adult gave a positive test (17 percent). This test was negative in all 50 controls studied, so the specificity was 100 percent. Although a negative FTA-ABS 19s IgM cannot be used to rule out congenital syphilis, a positive test should confirm suspected cases. The clinical features of congenital syphilis, as well as other laboratory investigations, re also discussed.
ABSTRACT
A simple method for preparation of permanent slides of urine sediments is described. To 100 ml of urine, 2 ml of a 40% formaldehyde solution is added. Centrifuge the formaldehyde-added urine specimen at 1000 rpm for 10 minutes. Discard the supernatant fluid and keep the sediment in a refrigerator overnight. The following day drop 1 ml of the resuspended sediment into a tube containing 3 ml of a 4% liquid gelatin. After mixing, drop 1 – 2 drops of the mixture on a glass slide, cover with a coverslip and seal. A permanent urine sediment slide is thus obtained. The cost is low but the result is excellent because the slides can be kept up to a period of not less eight months.