[Comparison of two lancets in the skin prick test].
BACKGROUND
The skin prick test is used to diagnose the allergic sensitization. Its results depend upon several factors, such as the lancet type. In Cuba, the most frequently used are: ALK lancet and blood lancet.


OBJECTIVE
To compare these two lancets regarding the size of the wheal, precision, sensitivity and specificity of the skin prick test and, finally, the preference of the patients to one of them.


METHODS
The study was performed in 60 allergic patients, aged 15-50 years, seen at the allergy service of Hospital Universitario Clínico Quirúrgico General Calixto García. The skin prick test was performed on the forearm of all patients included, using both lancet types. A negative control (diluent solution) was applied, together with a 54.3 mmol/L histamine solution in five replicates.


RESULTS
The mean size of skin reaction to histamine was 6 mm, using a 1 mm single peak lancet (ALK), size was 6.5 mm when using blood lancet (significant difference p < 0.05). Precision, sensitivity and specificity of ALK lancet were 9.7, 100 and 100%, respectively. On the other hand, the respective values for blood lancet were 15.9, 96 and 87%. Of those studied, 27% presented mild pain and 3% moderate pain using the ALK lancet; while 25% showed mild pain and 10% moderate pain using the blood lancet.


CONCLUSIONS
The ALK lancet showed more precision, sensitivity and specificity and it was preferred by the patients.
Departamento de Alergenos, Centro Nacional de Biopreparados (BIOCEN), Bejucal, La Habana, Cuba. rcastro@biocen.cu
Raúl Lázaro
RL
Castro Almarales
Sarah Idalmis
SI
Primo Valdés
Mayda
M
González León
Bárbara I
BI
Navarro Viltre
Mirta
M
Alvarez Castañeda
Catalina
C
Irarragorri Toledo
Mercedes
M
Ronquillo Díaz
Iris
I
García Gómez
Alexis
A
Labrada Rosado
D000293:Adolescent; D000328:Adult; D004867:Equipment Design; D006801:Humans; D008875:Middle Aged; D012680:Sensitivity and Specificity; D012882:Skin Tests / Q000295:instrumentation*