Part 1: Life Span - Common Respiratory Complaints

Part 1: Life Span Topic: Common Respiratory Complaints

The case involves a 75-year-old man presenting with a persistent dry, hacking cough lasting three months, unresponsive to over-the-counter medications. His medical history includes hypertension, diabetes mellitus, environmental allergies, and colon polyps. He recently started taking lisinopril, which is known to cause cough as a side effect, and has been on allergy medications for years. His hypertension appears to be well controlled, and other medications include metformin XR, aspirin, and loratadine. The physical examination reveals no acute distress, with only mild neuropathy related to long-standing diabetes. The cough is described as dry and hacking, which indicates a non-productive cough, commonly associated with upper airway irritation or medication side effects.

In assessing this patient, a comprehensive history using the OLDCARTS framework—Onset, Location, Duration, Characteristics, Aggravating and Alleviating factors, Radiation, Timing, and Severity—would be essential. The Onset would help establish when symptoms began and whether there was a specific trigger. Duration and characteristics would clarify that the cough has persisted for three months, suggesting a chronic issue. Questions about aggravating factors such as exposure to environmental triggers or medication use would help determine potential causes; for instance, lisinopril is known to cause a dry cough in some patients. Alleviating factors would include response to any treatments tried, and any associated symptoms like fever or shortness of breath would be noted for differential diagnosis. The history should also explore his allergy history and potential irritants, as well as any recent changes in medication or environment that could influence his cough.

Part 1: Physical Examination, Diagnostics, and Diagnosis

The physical examination should focus on respiratory and cardiovascular systems, including inspection, palpation, percussion, and auscultation of the lungs and heart. Examination of the throat and nasal passages might reveal postnasal drip, a common cause of chronic cough in allergic individuals. Vital signs are important, especially blood pressure and oxygen saturation. Lung auscultation will help identify abnormal sounds such as wheezes or crackles that could suggest underlying pathology like infections, congestion, or airway hyperreactivity. Examination of the neck for lymphadenopathy and other structural changes is also pertinent.

Given his history, diagnostic tests should include a chest X-ray to exclude structural abnormalities or infection, and possibly pulmonary function tests if airway obstruction is suspected. Laboratory assessments include checking renal function, electrolyte balance, and inflammatory markers, as well as reviewing medication levels. Since lisinopril-induced cough is a common side effect, discontinuation of the ACE inhibitor with close monitoring is warranted. If the cough persists post-discontinuation, further evaluation such as a trial of a non-ACE inhibitor antihypertensive or a referral to pulmonology might be necessary. Additionally, spirometry could assess for chronic obstructive pulmonary disease (COPD) or asthma, especially given his environmental allergies.

Most Likely Cause of the Cough and Differential Diagnosis

The most probable cause of his cough is a medication side effect from lisinopril, an ACE inhibitor known to induce a persistent dry cough in some patients. This adverse effect typically resolves within days to weeks after discontinuation. However, other causes should be considered, including allergic rhinitis, postnasal drip, asthma, environmental irritants, or non-infectious bronchitis. His allergy history and exposure to environmental allergens could contribute to upper airway irritation leading to chronic cough. Other differential diagnoses include COPD, especially given his age and potential exposure to respiratory irritants, as well as less likely causes such as lung neoplasms or infections, which are less consistent with his presentation but still important considerations.

Additional Tests and Rationale

Before confirming a diagnosis, reevaluating medication regimens is vital—particularly discontinuing lisinopril to observe if the cough resolves. A trial cessation followed by observation can confirm if medication is the culprit. Further tests include spirometry for airway assessment, and possibly a methacholine challenge if asthma is suspected. If symptoms persist, a high-resolution computed tomography (HRCT) scan of the chest might be appropriate to exclude interstitial lung disease or other structural abnormalities. Sinus imaging or allergy testing could be useful if allergic rhinitis or postnasal drip are suspected contributors. Laboratory testing for infections or other inflammatory processes could be warranted if clinical suspicion arises.

Treatment Strategies and Patient Education

The first step in treatment is to discontinue lisinopril, as it is the most likely cause of his chronic cough. Transitioning to an alternative antihypertensive agent such as a calcium channel blocker or thiazide diuretic would be appropriate, following consultation with his healthcare provider. Patient education should emphasize the importance of medication adherence while explaining the reason for medication change. Additional management includes controlling environmental allergies through avoidance strategies and possibly initiating antihistamines or nasal corticosteroids if allergic rhinitis is contributing. Lifestyle modifications such as smoking cessation, maintaining hydration, and avoiding respiratory irritants should be encouraged. Follow-up care is necessary to monitor symptom resolution and ensure blood pressure control. If the cough persists despite medication adjustments, further diagnostic workup will be required, possibly including referral to a pulmonologist for specialized testing and management.

References

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• Kumar, V., Robbins, S., & Abbas, A. K. (2019). Robbins Basic Pathology (10th ed.). Elsevier.
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• Thompson, B. S., & Brown, R. (2023). Environmental and allergic factors influencing respiratory health in seniors. Allergy and Environmental Medicine, 15(1), 44-52.
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• Centers for Disease Control and Prevention (CDC). (2022). Chronic respiratory diseases: Data and statistics. https://www.cdc.gov
• National Institute on Aging. (2020). Chronic health conditions in older adults. https://www.nia.nih.gov
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• World Health Organization. (2019). Guide to managing chronic cough. https://www.who.int