Does the Methacholine Test Reproduce Symptoms?

A positive methacholine challenge test in the absence of symptoms.

A 20-year-old white female nonsmoker presented to the pulmonary function laboratory for a methacholine challenge test. The patient denied wheezing, dyspnea, cough, or chest tightness. In fact, she competes in collegiate basketball and softball without respiratory complaints. She stated that her primary care physician wanted to “screen her for asthma,” because her father is asthmatic. Her medica...

A Rapid Methacholine Challenge Test in Patients with Asthmatic Symptoms

Methacholine challenge: test-shortening procedures.

STUDY OBJECTIVES Validation of test-shortening procedures for the 2-min tidal breathing methacholine challenge method. DESIGN Retrospective chart review. SETTING Tertiary-care university clinical pulmonary function laboratory. PATIENTS One thousand subjects aged 10 to 85 years (mean +/- SD, 44.5 +/- 16.0 years), 44.5% male, referred for methacholine challenge. INTERVENTION Two-minute ti...

Methacholine challenge test as an adjunctive investigative tool in patients with asthma-like symptoms: the Sabah experience.

INTRODUCTION Patients with asthma-like symptoms pose a diagnostic dilemma when physical examination is normal. The usual practice in Malaysia would be to give empirical asthma treatment. Bronchial challenge test (BCT) is widely used in many countries to diagnose asthma objectively but it is not widely available in Malaysia. OBJECTIVE To describe our experience with BCT using methacholine at Q...

Cyclooxygenase inhibition does not alter methacholine-induced sweating.

Cholinergic agents (e.g., methacholine) induce cutaneous vasodilation and sweating. Reports indicate that either nitric oxide (NO), cyclooxygenase (COX), or both can contribute to cholinergic cutaneous vasodilation. Also, NO is reportedly involved in cholinergic sweating; however, whether COX contributes to cholinergic sweating is unclear. Forearm sweat rate (ventilated capsule) and cutaneous v...