[Sensitivity and specificity of the modified epicutaneous patch test in the diagnosis of respiratory allergy to Dermatophagoides pteronyssinus]

Rev Alerg Mex. 2019 Jan-Mar;66(1):38-43. doi: 10.29262/ram.v66i1.533.
[Article in Spanish]

Abstract

Background: The skin prick test is recognized as the gold standard for the specific diagnosis of allergy.

Objective: To determine the sensitivity and specificity of the epicutaneous patch test that has been modified for the diagnosis of respiratory allergy to Dermatophagoides pteronyssinus.

Methods: An observational, interpretative, prolective, and transversal study. The included patients were between 6 and 49 years old, with symptoms of a respiratory allergy, and a skin test was performed on them by using the European standardized prick test and a modified epicutaneous patch test with the variable of the scarification that occurred before the antigen was applied, and its homogenization with a wooden applicator, which occurred after the antigen was applied. The levels of sensitivity, specificity, and prevalence influence and positive and negative predictive values were calculated.

Results: 104 patients were included, of which 72 (69.2%) were women. The age category of the patients was 24 ± 11.3 years of age. 78.9% of the patients were diagnosed with allergic rhinitis, 1.9% were diagnosed with asthma, and 19.2% were diagnosed with both rhinitis and asthma. The prevalence of the respiratory allergy to Dermatophagoides pteronyssinus was of 62.5%; 94.23% with a correct diagnosis. The sensitivity and specificity of the test was of 93.85% and 94.87%; the positive and negative predictive values were of 96.83% and 90.24%, and the positive and negative likelihood ratios were of 18.30 and 0.06.

Conclusions: The modified epicutaneous patch test was highly sensitive and specific; it decreased the risk of allergen carryover and it lowered the cost of the material that was used.

Antecedentes: La prueba por punción cutánea es el estándar de oro en el diagnóstico específico de alergia. Objetivo: Determinar sensibilidad y especificidad de la prueba epicutánea modificada para el diagnóstico de alergia respiratoria a Dermatophagoides pteronyssinus. Métodos: Estudio observacional, interpretativo, prolectivo y transversal. Se incluyeron pacientes de seis a 49 años de edad, con cuadro clínico de alergia respiratoria, en quienes se realizó punción cutánea con técnica europea y prueba epicutánea con la variante de escarificación previa a la aplicación del antígeno y posterior homogenización del mismo con aplicador de madera. Se calculó sensibilidad, especificidad, influencia de la prevalencia, valores predictivos positivo y negativo. Resultados: Se incluyeron 104 pacientes, 72 (69.2 %) del sexo femenino. La edad fue de 24 ± 11.3 años, 78.9 % tuvo diagnóstico de rinitis alérgica, 1.9 % de asma y 19.2 % de rinitis y asma. La prevalencia de alergia respiratoria a Dermatophagoides pteronyssinus fue de 62.5 %; 94.23 % estaba correctamente diagnosticado. La sensibilidad y especificidad de la prueba fue de 93.85 y 94.87 %, los valores predictivos positivo y negativo de 96.83 y 90.24 % y los cocientes de probabilidades positivo y negativo de 18.30 y 0.91. Conclusiones: La prueba epicutánea modificada fue altamente sensible y específica, disminuyó el riesgo de contaminación por arrastre de alérgenos y los costos en el material utilizado.

Keywords: Dermatophagoides pteronyssinus; Respiratory allergy diagnosis; Skin prick test.

Publication types

  • Observational Study

MeSH terms

  • Adolescent
  • Adult
  • Animals
  • Asthma / diagnosis*
  • Asthma / immunology*
  • Child
  • Cross-Sectional Studies
  • Dermatophagoides pteronyssinus / immunology*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Patch Tests / methods*
  • Prospective Studies
  • Rhinitis, Allergic / diagnosis*
  • Rhinitis, Allergic / immunology*
  • Sensitivity and Specificity
  • Young Adult