Why Do Some Suspected Silent Reflux Patients Test Negative for Pepsin?
At Peptest, we frequently hear from patients who are grappling with distressing upper airway or laryngeal symptoms that can severely impact their quality of life. These symptoms are often difficult to diagnose, leaving both patients and doctors searching for effective treatments.
Many patients have used Peptest to identify the presence of pepsin in their saliva, gaining reassurance and a clear path forward with a positive diagnosis. However, some patients receive consistently negative results for pepsin, suggesting that another cause might be responsible for their symptoms.
A negative Peptest in such cases is often a more important discovery in the eyes of the physician and may indicate that an alternative diagnosis needs to be sought.
So why do we sometimes get a negative result for pepsin in suspected silent reflux patients?
The answer is complex. First, it's important to recognise that no diagnostic test is 100% accurate—there's always a small chance of a false negative. However, if multiple diagnostic tests, including several Peptest results, suggest that reflux is not the cause, it's vital to consider other possible explanations for the symptoms.
We recently came across the reflux guidelines issued by the University of Michigan and I thought they might help to answer some of these questions. The excerpt reproduced below specifically discusses the atypical signs of GERD or LPR (the full text can be found here https://michmed-public.policystat.com/policy/10514608/latest/#autoid-5dgpg).
Extract from GERD practice guidelines:
Reflux may manifest atypically as pulmonary (asthma, chronic cough), ENT (laryngitis, hoarseness, sore throat, globus, throat clearing) or cardiac (chest pain) symptoms, often without symptoms of heartburn and regurgitation. Mechanisms for this include direct contact and microaspiration of small amounts of noxious gastric contents into the larynx and upper bronchial tree (triggering local irritation, and cough), and acid stimulation of vagal afferent neurons in the distal esophagus (causing non-cardiac chest pain and vagally-mediated bronchospasm/asthma). Laryngeal neuropathy has been implicated recently as a cause for laryngitis symptoms and cough.
Pulmonary
Asthma and GERD are common conditions that often coexist with 50-80% of asthmatics having GERD and up to 75% having abnormal pH testing. However, only 30% of patients who have both GERD and asthma will have GERD as the cause for their asthma. The causal relationship between asthma and GERD is difficult to establish because either condition can induce the other (GERD causing asthma as above, and asthma causing increased reflux by creating negative intrathoracic pressure and overcoming LES barrier). Furthermore, medications used for asthma, such as bronchodilators, are associated with increased reflux symptomatology. Historical clues to GERD-related asthma may include asthma symptoms that worsen with big meals, alcohol, and supine position, or adult-onset and medically refractory asthma. Diagnostic testing with pH probe and EGD have limited utility in establishing causality in this population.
Ear, Nose, and Throat (ENT)
In patients presenting with ENT symptoms, 10% of hoarseness, up to 60% of chronic laryngitis and refractory sore throat, and 25-50% of globus sensation may be due to reflux. EGD and pH testing are frequently normal in this population. Reflux laryngitis is usually diagnosed based on the laryngoscopic findings of laryngeal erythema and edema, posterior pharyngeal coblestoning, contact ulcers, granulomas, and interarytenoid changes. However, a recent study found these signs to be nonspecific for GERD, noting at least 1 sign in 91 of 105 (87%) healthy people without reflux or laryngeal complaints. Many of these signs may be due to other laryngeal irritants such as alcohol, smoking, postnasal drip, viral illness, voice overuse, or environmental allergens, suggesting their use may contribute to over-diagnosis of GERD. This also may explain why many patients (up to 40-50%) with laryngeal signs don’t respond to aggressive acid therapy. Posterior laryngitis, medial erythema of false/true vocal cords and contact changes (ulcers and granulomas) are more common in GERD patients and predict a better response to acid reduction.
While we may not entirely agree with every aspect of the symptoms breakdown, the core message is clear: reflux can cause atypical symptoms such as coughing and hoarseness, but it may not be the only cause of these symptoms. Peptest is a reliable diagnostic tool for providing evidence of reflux in various types of patients. A positive Peptest result indicates that managing reflux could alleviate your symptoms. Conversely, a negative Peptest result is just as important, as it signals that other factors may be contributing to your condition, guiding physicians in the ongoing treatment process.
To ensure you get the most accurate diagnosis using Peptest, keep these tips in mind:
- Collect Samples When Symptomatic: Always collect your samples when experiencing symptoms.
- Throat Clearing: Before collecting saliva, clear your throat with a cough to ensure the saliva from your throat and mouth are mixed.
- Before Lifestyle Changes or Medication: Collect samples before making any lifestyle changes or starting new medications to confirm that reflux is the cause.
- Follow Instructions Carefully: Always follow the provided instructions and note any factors that might affect your reflux.
For those struggling with atypical reflux symptoms, Peptest offers an easy, non-invasive and reliable way to identify or rule out reflux as the cause. Whether your test results are positive or negative, they provide critical information that can guide your treatment and bring you closer to finding relief.
Keywords:
- Atypical reflux symptoms
- GERD diagnosis
- LPR symptoms
- Peptest
- Pepsin test
- Reflux testing
- Non-invasive reflux test
- Chronic cough diagnosis
- Hoarseness causes
- Reflux laryngitis
- Acid reflux detection