Cough - differential diagnosis: It’s not all asthma! Dr Chris Davies MD FRCP Consultant Physician RBH / Dunedin Hospital Reading

Prevalence % 7% has significant inpact on QoL Primary care survey 14% men 10% women report coughing on > 50% days of year

Cough - Definition acute< 3 weeks (subacute3 - 8 weeks) chronic< 8 weeks

Cough - Definition Acute: Causes?

Cough - Definition Acute: Causes? –Infections Viral Bronchitis Pneumonia Whooping cough –Non-infectious Asthma/COPD flares Environmental exposures Drugs Foreign body etc

Miscellaneous

Mechanisms

Pathophysiology Cough reflex sensitive –Atmospheric changes –perfumes –ACE I –GORD

Causes of cough

smoking lung disorders (> 50%) chronic cough syndromes drugs - ACE Inhibitors mediastinal masses cardiac upper GI neurological idiopathic & psychogenic

Causes of Chronic Cough Syndromes?

Causes of Chronic Cough Syndromes Gastro-oesophageal reflux Rhinosinusitis (postnasal drip) Asthma – cough variant Eosinophilic bronchitis Chronic tonsillar enlargement Angiotensin-converting enzyme inhibitor medications

Impact of Chronic Cough

Physical –Cough syncope –Chest pain –Urinary incontinence Psychological –Social exclusion –Marital dysharmony –Depression

Impact of Chronic Cough Physical –Cough syncope –Chest pain –Urinary incontinence Psychological –Social exclusion –Marital dysharmony –Depression

Chronic cough

Chronic cough – how to approach? Red flag symptoms Urgent CXR and pathway

Chronic cough – how to approach? haemoptysis chest pain weight loss night sweats progressive/persistent symptoms (esp cough) heavy smoking history asbestos exposure

CXR - Urgent pathway

Initial strategy Ask about –dry or productive (? purulent) –other respiratory symptoms e.g. SOB & wheeze –nasal symptoms & sensation of post-nasal drip –dyspepsia & waterbrash –history of atopic illness or severe LRTI –history of heart disease –drugs taken –smoking history –occupation, pets, hobbies

When to order a chest x-ray? In the absence of Red flag symptoms –All chronic cough (> 8 weeks duration) –X-ray abnormal – treat ± refer

But usually…..

Other tests Spirometry – in all chronic cough pts –Usually normal –may be normal in cough variant asthma but may be changes in flow volume loop

Spirometry

Flow volume loops Flow (l/min) Volume (l) (a) normal (b) asthma (c) emphysema (d) restrictive (e) upper airway obstruction

Chest x-ray “normal”? Is there a possible lung disease? –Asthma –COPD –Bronchiectasis –Early lung fibrosis Gastro-oesophageal reflux (GORD) ? Rhinosinusitis with post nasal drip (PND) ? Stop ACE inhibitors if possible

Chronic Cough – the majority… GORD +/- laryngopharngeal reflux Rhinosinusitis/PND Cough variant asthma with BHR Eosinophilic bronchitis and finally… Unexplained Chronic Cough Syndrome

Clues in the history Asthma

Clues in the history Asthma –Nocturnal, exposure to cold, exercise, aerosols –May be symptoms of wheeze, sputum –Family history, atopy, pets –May be a previous response to steroids –little/no variable airflow obstruction Eosinophilic bronchitis –Very similar….

Clues in the history GORD

Clues in the history GORD –with or after meals –on phonation / laughter – minutes after getting out of bed –Often not at night unless severe –Postural – e.g in car, sitting on phone –laryngopharngeal reflux – throat clearing –Wheeze afterwards - aspiration –May get dysfunctional respiratory symptoms

GORD - pathophysiology Acid and non-acid reflux –Lower sphincter Mornings – after rising Post prandial – 10 mins later –Hiatus Hernia –Gastrointestinal dysmotility –Diaphragmatic movement Talking Telephone

Clues in the history Post nasal drip

Clues in the history Post nasal drip –May be no nasal or upper airway symptoms –May be sensation of drip or throat clearing –No ‘test’ – treatment trial may be 1 st line of intervention

But which is the cause? All (asthma, GOR, PND) may exhibit no other symptoms of the disorder All are common & frequently co-exist Positive predictive value of characteristic symptoms is limited ( %) Multiple causes ( %)

Empirical trials of treatment Can be diagnostic tool in chronic cough Guided by most likely cause/best guess once know spirometry and CXR normal Treat with relatively high dose & prolonged duration e.g. 4-6 weeks each

GORD PPI ( eg Omeprazole mg bd, 8 weeks) Consider adding ranitidine too dietary advice, lifestyle modification Add prokinetics and antacids

Cough variant asthma (inhaled beta-2 agonists) – don’t usually help inhaled steroids (400 mcg BDP bd, 8 weeks) –Work in eosinophilic bronchitis too Oral steroids ? –e.g. Prednisolone 30mg daily – days

Rhinosinusitis/PND nasal steroids (for ≈ 2 months) –Correct technique essential nasal decongestants (short term only) Older generation antihistamines e.g. promethazine (Phenergan®)

Still coughing? No response – –treat other cough syndromes in turn Partial response –escalate treatment(s)

Still coughing? No response – treat other cough syndromes in turn Partial response – escalate treatment –Asthma – Monteleukast, Theophylline, short course oral steroids –GOR – Alginate (5-10 ml qds), double dose PPI, H2 blocker e.g ranitidine, pro-kinetic e.g. domperidone or metoclopramide tds –PND – antihistamine & decongestant, high strength nasal steroid, saline douches

Still coughing? No response – treat other cough syndromes in turn Partial response – escalate treatment –Asthma – Monteleukast, Theophylline, short course oral steroids –GOR – Alginate (5-10 ml qds), double dose PPI, H2 blocker e.g ranitidine, pro-kinetic e.g. domperidone or metoclopramide tds –PND – antihistamine & decongestant, high strength nasal steroid, saline douches

Still coughing? No response – treat other cough syndromes in turn Partial response – escalate treatment –Asthma – Monteleukast, Theophylline, short course oral steroids –GOR – Alginate (5-10 ml qds), double dose PPI, H2 blocker e.g ranitidine, pro-kinetic e.g. domperidone or metoclopramide tds –PND – antihistamine & decongestant, high strength nasal steroid, saline douches

But has it really worked? Patients may have difficulty confirming improvement Objective scores…

But has it really worked? Patients may have difficulty confirming improvement Objective scores… Consider withdrawing and/or reducing treatment & monitor symptoms 4 weeks

Leicester Cough Questionnaire. © Birring S S et al. Thorax 2003;58:

Chronic cough

History when seen Cough 8 years Possibly started with infection Dry Worse when gets up and when lies down Worse winter Worse laughter

History when seen Breathless stairs Wheeze coughing not otherwise No GORD or post nasal symptoms Tried salbutamol / PPI ?dose Examination – few crackles L base Spiro/bloods normal

History when seen Given BCM again and PPI HRCT

Pitfalls Inadequate treatment trial –duration –strength –compliance Multiple causes Variability of chronic cough

When to refer? A number of factors will influence this - –Confidence in continuing treatment trials –Time consuming for GP –Patient pressure that ‘something is wrong’ –Partner pressure

‘Secondary care’ investigations Repetition of history Examination Spirometry (variability) Review imaging In depth discussion about causes/treatment Further empirical trials Tests

‘Secondary care’ investigations High resolution CT scan of lungs –Often important after trials to –A) reassure patient nothing more serious –B) identify any structural cause

‘Secondary care’ investigations GORD Tests? –OGD – often no oesophagitis –24 hour oesophageal pH monitoring –Oesophageal manometry –May not correlate with symptoms

‘Secondary care’ investigations Bronchial challenge test –High NPV, low PPV Induced sputum (eosinophils) Nitric oxide –Reduces in response to steroids CT sinuses Nasendoscopy

Heart-sinks or Unexplained Chronic Cough Syndrome

Unexplained Chronic Cough Syndrome Can be due to: –1. Inadequate assessment –2. Poor Compliance treatments –3. Ineffective treatment These patients probably have a “hypersensitive cough reflex”

Unexplained Chronic Cough Syndrome Typically –Middle aged women – perimenopausal –Often triggered by infection –Increased anxiety/depression levels

Unexplained Chronic Cough Syndrome Treatments are limited…stop as much as possible Opiates act centrally & locally on OP-3 receptor usually codeine linctus or pholcodine initially side effects a problem SALT / Physiotherapy Local anaesthetics (nebulised lignocaine) Gabapentin/TCADs –RCT –Maximal dose tolerated

Summary chronic cough is common limited number of common causes diagnosis is difficult but therapeutic trials are often effective – careful explanation helpful for patients secondary care approach may require multi- speciality input % of patients improve (eventually!) UCCS – may require novel treatments