Lugo RSO, García CML, Terán JLM

Language: Spanish
References: 10
Page: 29-33
PDF size: 220.82 Kb.

ABSTRACT

Background: In the clinical assessment of the patient with respiratory complaints, a series of signs and symptoms are traditionally considered suggestive of allergic origin. The presence of those «classical» symptoms and signs can trigger patient referral, allergy skin test, laboratory workup and specific treatment. A quick and reliable clinical examination can thus be essential for the initial management, especially to distinguish between chronic infection and allergy, in the context of a high demand for health care services and a scarcity of resources. Objective: We aimed to assess the diagnostic usefulness of respiratory signs and symptoms typically considered suggestive of allergy, and to identify a combination of signs and symptoms that best predict a final diagnosis of atopy. Methods: We clinically assessed 50 consecutive patients who came for a first-time allergy consultation. Family history, patient symptoms and clinical examination were registered in a data sheet; each classical symptom, sign or background was considered a diagnostic test, and its usefulness to predict a final diagnosis of atopy was assessed using contingency tables, with the allergy skin test result as the standard of reference. Predictive values and likelihood ratios (LR) were calculated for each component of the clinical evaluation. Results: Mean age was 13.6 years (range 2 to 51), 52% male sex, and 64% positive allergy skin tests. The components from the clinical evaluation with the highest positive LR (LR+) were: parental antecedent (LR+ 2.25), sneezing spells (LR+ 1.77), known trigger (LR+ 2.33), and double inferior palpebral fold («Dennie Morgan ligns», LR+ 3.00), as well as wheezing on auscultation (LR+ 4.03). The combination of three components (a construct): positive family history, sneezing spells, and double inferior palpebral fold, resulted in a LR+ of 5.18. Discussion: Most signs and symptoms did not prove to be, in and by themselves, useful to predict a final diagnosis of atopy. When considered sequentially or combined, however, the clinical components classically considered of allergic origin, can acceptably predict a positive skin allergy test.

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