Chapter 42: Cough

Cough is one of the five most common symptoms presenting in family practice. There is a wide range of causes (see TABLE 42.1) with the great majority being minor and self-limiting, although the possibility of serious causes such as bronchial carcinoma should always be kept in mind.

It is a feature of smokers, who often have a morning cough with little sputum. Coughing can also be initiated by pleural irritation. It is a reflex that provides an essential protective service. It serves to remove substances that may have been accidentally inhaled and removes excess secretions or exudates that may accumulate in the airway.

A summary of the diagnostic strategy model is presented in TABLE 42.2.

Probability diagnosis

The most common cause of cough is an acute respiratory infection, whether a URTI or acute bronchitis.³ Persistent coughing with a URTI is usually due to the development of sinusitis with a postnasal drip.

Chronic bronchitis is also a common cause of cough.

Serious disorders not to be missed

Bronchial carcinoma must not be overlooked. A worsening cough is the commonest presenting problem. A bovine cough is suggestive of cancer: the explosive nature of a normal cough is lost when laryngeal paralysis is present, usually resulting from bronchial carcinoma infiltrating the left recurrent laryngeal nerve.

Chronic cough may be the first presentation of Pneumocystis jiroveci pneumonia in an HIV-infected patient. Careful but tactful questioning of the patient in relation to IV drug use, sexual practice and previous blood transfusions is important. Important causes of a chronic cough are summarised in TABLE 42.3.

The possibility of a foreign body should always be kept in mind, especially in children, and severe infections such as TB and pulmonary abscess must not be misdiagnosed.

It is also important not to overlook asthma in which a nocturnal cough, without wheezing, is a feature in children.

Pitfalls

Causes that tend to be overlooked, especially in the presence of a normal X-ray, are gastro-oesophageal reflux, postnasal drip and asthma. Gastro-oesophageal reflux is more common as a cause of reflex coughing, especially at night, than appreciated. Whooping cough, especially immunisation-modified, can be difficult to diagnose, particularly if the characteristic whoop is absent.

General pitfalls

• Attributing cough due to bronchial carcinoma in a smoker to ‘smoker’s cough’

• Overlooking TB, especially in the elderly, by equating symptoms to old age, bronchitis or even smoking

• Overlooking the fact that bronchial carcinoma can develop in a patient with other pulmonary conditions, such as chronic bronchitis

• Being slow to order a chest X-ray

• Failing to recognise that pertussis presents in adults

Seven masquerades checklist

The applicable masquerade is drugs, many of which can produce a wide variety of disorders of the respiratory tract that cause a cough. Pulmonary infiltration with fibrosis may result from some cytotoxic drugs, especially bleomycin. Over 20 different drugs are known to produce an SLE-like syndrome, sometimes complicated by pulmonary infiltrates and fibrosis. Cough can be a feature of some of the ACE inhibitors and beta blockers, inhaled steroids and sulfasalazine.

Psychogenic considerations

A cough can occur for psychosocial reasons. Coughing is under cerebral control and a slight cough before commencing a speech is normal and presumably assists in clearing mucus from around the vocal cords.⁶ This can readily become a nervous habit or mannerism. A typical ‘psychogenic’ cough is barking in quality—the ‘Cape Barren goose’ cough. It does not occur during sleep.

History

The nature of the cough may provide important diagnostic clues, but it is the associated symptoms, such as the nature of the sputum, breathlessness, wheezing and constitutional symptoms, that provide the most helpful diagnostic value. A diagnosis of asthma should not be made if the predominant symptom is cough without airflow limitation such as wheeze. A history of smoking habits, past and present, is essential and an occupational and hobby history requires investigation. Significant occupations (past or present) include mining (pneumoconiosis), aircraft manufacturing (asbestosis and mesothelioma), farming (‘farmer’s lung’—allergic pneumonitis from mouldy hay) and bird handling (‘bird fancier’s lung’—allergic alveolitis or psittacosis from pigeons or budgerigars). A past history of recurrent lung infections from childhood is suggestive of cystic fibrosis and bronchiectasis, a history of hay fever and eczema suggests asthma, while a family history involves asthma, cystic fibrosis, emphysema (α₁-antitrypsin deficiency) and tuberculosis.

Key questions⁷

• How would you describe the cough?

• How long has the cough been present?

• Do you cough up sputum?

• Describe the sputum, especially its colour.

• Is there any blood in the sputum?

• How much sputum do you produce—a teaspoonful, an eggcupful or more?

• Is there a burning sensation in your throat or chest when you cough?

• Have you noticed any other symptoms?

• What about chest pain or fever, shivers or sweats?

• Do you have a wheeze?

• Have you had previous attacks of wheezing or hay fever?

• Is there a history of asthma in your family?

• Have you lost weight?

• Has anyone in the family had TB or a persistent cough?

• How much do you smoke?

• Are you exposed to any smoke or fumes?

• What kind of work do you do?

• Where have you worked in the past?

• Is there a chance you have been exposed to asbestos?

• Do you keep birds or pets at home?

• Do you have any birds nesting outside your bedroom?

• Is there a possibility of a foreign body such as a peanut ‘having gone down the wrong way’?

• Have you had an operation recently or been confined to bed?

• Have you noticed any swelling of your legs?

• Have you been exposed to birds such as pigeons?

Examination

Physical examination includes a general examination with a search for features such as enlarged cervical or axillary glands, which may indicate bronchial carcinoma, as would Horner syndrome (constricted pupil, ptosis). A careful examination of the lungs and cardiovascular system is also appropriate. Fine crackles on auscultation indicate pulmonary oedema of heart failure, interstitial pulmonary fibrosis and early lobar pneumonia, while coarse crackles indicate resolving pneumonia, bronchiectasis and TB. Careful inspection of the sputum forms an important part of the physical examination of the lungs. This should include its colour and consistency, presence of particulate matter and a 24-hour sputum watch.

Investigations

This applies particularly to patients with haemoptysis. Investigations include:⁸

• haemoglobin, blood film and white cell count

• sputum cytology and culture

• ESR (elevated with bacterial infection, bronchiectasis, TB, lung abscess and bronchial carcinoma), CRP

• pulmonary function tests/spirometry

• radiology:

  • – plain chest X-ray (shows many problems)

  • – tomography: helps more precise localisation of lesion, may show cavitation

  • – bronchography: shows bronchiectasis (a very unpleasant procedure)

  • – CT scanning (more sensitive than plain X-ray)

  • – CT pulmonary angiogram

  • – ventilation/perfusion isotope scan: for pulmonary infarction

  • – echocardiogram (pulmonary hypertension)

• skin tests

• lung biopsy

• bronchoscopy (best at time of haemoptysis)

However, all that is needed initially is a plain chest X-ray.

Diagnostic characteristics

There are important characteristics of cough that may point to the causation. TABLE 42.1 compares typical causes of dry and productive cough.

• Brassy → tracheitis and bronchitis (major bronchi); extrinsic pressure on trachea (e.g. tumour)

• Barking → laryngeal disorders (e.g. laryngitis)

• Croupy (with stridor) → laryngeal disorders (e.g. laryngitis, croup)

• Hollow ‘bovine’ (no power) → vocal cord paralysis (left-recurrent laryngeal nerve)

• Weak cough → indicates bronchial carcinoma

• Paroxysmal with whoops → whooping cough

• Painful → tracheitis; left ventricular failure

• Dry chronic → GORD, drugs (e.g. ACE)

• Nocturnal cough →

  • – asthma

  • – left ventricular failure

  • – postnasal drip

  • – chronic bronchitis

  • – whooping cough

• Waking cough →

  • – bronchiectasis, asthma

  • – chronic bronchitis

  • – GORD

• Changing posture →

  • – bronchiectasis

  • – lung abscess

• Meals →

  • – hiatus hernia (possible)

  • – oesophageal diverticulum

  • – tracheo-oesophageal fistula

• Wheezing →

  • – asthma

• Breathlessness →

  • – asthma

  • – left ventricular failure

  • – COPD

Sputum

A healthy, non-smoking individual produces approximately 100–150 mL of mucus a day. This normal bronchial secretion is swept up the airways towards the trachea by the mucociliary clearance mechanism and is usually swallowed. The removal from the trachea is assisted also by occasional coughing although this is carried out almost subconsciously.⁶

Excess mucus is expectorated as sputum. The commonest cause of excess mucus production is cigarette smoking. Mucoid sputum is clear and white.

• Clear white (mucoid) → normal or uninfected bronchitis

• Yellow or green (purulent) → due to cellular material (neutrophils or eosinophil granulocytes)

  • – ± infection (not necessarily bacterial infection)

  • – asthma due to eosinophils

  • – bronchiectasis (copious quantities)

• Rusty → lobar pneumonia (S. pneumoniae): due to blood

• Thick and sticky → asthma

• Profuse, watery → alveolar cell carcinoma

• Thin, clear mucoid → viral infection

• Redcurrant jelly → bronchial carcinoma

• Profuse and offensive → bronchiectasis; lung abscess

• Thick plugs (cast-like) → allergic bronchopulmonary Aspergillus; bronchial carcinoma

• Pink frothy sputum → pulmonary oedema

Haemoptysis

Blood-stained sputum (haemoptysis), which varies from small flecks of blood to massive bleeding, requires thorough investigation. Always consider malignancy or TB. Often the diagnosis can be made by chest X-ray. Causes are presented in TABLE 42.4. Haemoptysis must be distinguished from blood-stained saliva caused by nasopharyngeal bleeding or sinusitis and also from haematemesis.⁶ Acute bronchitis produces streaky haemoptysis.

Productive cough

• Chronic bronchitis: mucoid or purulent; rarely exceeds 250 mL per day⁶

• Bronchiectasis: purulent sputum; up to

  500 mL/day

• Asthma: mucoid or purulent; tenacious sputum

• Lung abscess: purulent and foul-smelling

• Foreign body: can follow impaction

Cough in children is a very common symptom, but troublesome persistent cough is a great cause of anxiety among parents and probably the commonest symptom for which the family doctor is consulted. Age-related causes of chronic cough (present at least 4 weeks) are presented in TABLE 42.5. Most children with chronic cough do NOT have asthma. A chest X-ray is advisable for a persistent cough.

Common causes of cough generally are:

• asthma

• recurrent viral bronchitis

• acute URTIs

• allergic rhinitis

• croup

Disorders not to be missed are:

• asthma

• cystic fibrosis

• inhaled foreign body

• tracheo-oesophageal fistula

• pneumonia

• whooping cough

Several clinicians describe the catarrhal child syndrome as the commonest cause of cough.³ This refers to children who develop a postnasal drip following acute respiratory infection and allergic rhinitis. Recurrent cough in children can usually be explained by recurrent viral respiratory infections which commonly occur when first exposed to other children. Their airways tend to be overactive. There is a slight predisposition to asthma.

If asthma is suspected, a therapeutic trial of salbutamol 200 mcg 4 hourly via a spacer may be worthwhile.

Psychogenic causes

Habit cough can occur in children, especially those with a history of school phobia. The cough does not occur during sleep and remains unchanged with exertion or infection.

Croup (laryngotracheobronchitis)

Clinical features

• Characteristic harsh barking inspiratory cough with stridor

• Prodrome of URTI for 2 days

• Sounds like a dog barking or a seal

• Children 6 months to 6 years

• Fever variable (rarely >39°)

• Usually 11 pm to 2 am

• Auscultation confirms inspiratory stridor

• Occurs in small local epidemics

Management—refer to CHAPTER 96.

Important causes of cough to consider in the elderly include chronic bronchitis, lung cancer, pulmonary infarct (check calves), bronchiectasis and left ventricular failure, in addition to the acute upper and lower respiratory infections to which they are prone. It is important to be surveillant for bronchial carcinoma in an older person presenting with cough, bearing in mind that the incidence rises with age. One study found the causes of chronic cough in the elderly to be postnasal drip syndrome 48%, gastro-oesophageal reflux 20% and asthma 17%.¹⁰

Respiratory infections, especially those of the upper respiratory tract, are usually regarded as trivial, but they account for an estimated one-fifth of all time lost from work and three-fifths of time lost from school, and are thus of great importance to the community.¹¹ The majority of respiratory infections are viral in origin and antibiotics are therefore not indicated.

URTIs are those involving the nasal airways to the larynx, while lower respiratory tract infections (LRTIs) affect the trachea downwards.

Combined URTIs and LRTIs include influenza, measles, whooping cough and laryngotracheobronchitis.

The common cold (acute coryza)

This highly infectious URTI, which is often mistakenly referred to as ‘the flu’, produces a mild systemic upset and prominent nasal symptoms (see FIG. 42.1).

Clinical features

• 24–48 hours of weakness

• Malaise and tiredness

• Sore, runny nose

• Sneezing

• Sore throat

• Slight fever

Other possible symptoms:

• headache

• hoarseness

• cough

The watery nasal discharge becomes thick and purulent in about 24 hours and persists for up to a week. Secondary bacterial infection is uncommon.

Management

Advice to the patient includes:

• rest—adequate sleep and rest

• drink copious fluids

• stop smoking (if applicable)

• analgesics—paracetamol (acetaminophen) or aspirin (max. 8 tablets a day in adults)

• steam inhalations for a blocked nose

• cough mixture for a dry cough

• gargling aspirin in water or lemon juice for a sore throat (avoid aspirin in children <16 years)

• vitamin C powder or tablets (e.g. 2 g daily) may aid recovery; however, clinical trials are inconclusive

• clinical trials of vitamin C, zinc lozenges and echinacea give contradictory results to date¹¹

Influenza

Influenza causes a relatively debilitating illness and should not be confused with the common cold. The differences are presented in TABLE 42.6. The incubation period is usually 1–3 days and the illness commences abruptly with a fever, headache, shivering and generalised muscle aching (see FIG. 42.2).

Clinical criteria¹²

During an influenza epidemic:

• fever >38°C plus at least one respiratory symptom and one systemic symptom

• cough (dry)

• sore throat

• coryza

• prostration or weakness

• myalgia

• headache

• rigors or chills

Complications

• Tracheitis, bronchitis, bronchiolitis

• Secondary bacterial infection

• Pneumonia due to Staphylococcus aureus (mortality up to 20%)¹

• Toxic cardiomyopathy with sudden death (rare)

• Encephalomyelitis (rare)

• Depression (a common sequela)

Management

Advice to the patient includes:

• rest in bed until the fever subsides and patient feels better

• analgesics: paracetamol and aspirin or ibuprofen are effective, especially for fever

• fluids: maintain high fluid intake (water and fruit juice)

• freshly squeezed lemon juice and honey preparation

• Neuraminidase inhibitors (cover influenza A and B):

  • zanamivir (Relenza) 10 mg by inhalation bd for 5 days

  • oseltamivir (Tamiflu) 75 mg (o) bd (child 2 mg/kg) for 5 days

  • Both should be commenced within 36 hours of onset and given for 5 days.

Note: These antiviral agents have questionable benefit in a low-risk population, but treatment for vulnerable patients is appropriate.

Prevention

Influenza vaccination offers some protection for up to 70% of the population for about 12 months.¹ (See CHAPTER 9.)

Swine origin flu

(The swine variety of H1N1 influenza A.)

This strain presents with typical influenza symptoms commonly accompanied by gastrointestinal symptoms (especially diarrhoea). Like avian flu, it tends to occur in a pandemic and affects the young in particular.

The treatment is the same as for influenza in general, with neuraminidase inhibitors. A vaccine is now available.

Avian (bird) flu due to H5N1 strain: refer to CHAPTER 28.

Middle East respiratory syndrome (MERS–CoV)

This is a viral respiratory disease of varying severity caused by a novel coronavirus. Symptoms include cough, fever and dyspnoea. Endemic to the Middle East, especially Saudi Arabia. No specific treatment but supportive. Significant mortality rate.

Acute bronchitis

This is acute inflammation of the tracheobronchial tree that usually follows an upper respiratory infection. Although generally mild and self-limiting, it may be serious in debilitated patients.

Clinical features

Features of acute infectious bronchitis are:

• cough and sputum (main symptoms)

• wheeze and dyspnoea

• usually viral infection

• can complicate chronic bronchitis—often due to Haemophilus influenzae and Streptococcus pneumoniae

• scattered wheeze on auscultation

• fever or haemoptysis (uncommon)

• It improves spontaneously in 4–8 days in healthy patients.

Treatment^12,14,15

• Symptomatic treatment

• Inhaled bronchodilators for airflow limitation

• Antibiotics usually not needed in previously healthy adult or child

• Use antibiotics only if evidence of acute bacterial infection with fever, increased sputum volume and sputum purulence:

  • amoxycillin 500 mg (o) 8-hourly for 5 days

  • or

  • especially if mycoplasma suspected, doxycycline 200 mg (o) statim, 100 mg, daily for 5 days.

Chronic bronchitis

This is a chronic productive cough for at least 3 successive months in 2 successive years:

• wheeze, progressive dyspnoea

• recurrent exacerbations with acute bronchitis

• occurs mainly in smokers

Refer to COPD (in CHAPTER 83).

This is inflammation of lung tissue. It usually presents as an acute illness with cough, fever and purulent sputum plus physical signs and X-ray changes of consolidation.

However, the initial presentation of pneumonia can be misleading, especially when the patient presents with constitutional symptoms (fever, malaise and headache) rather than respiratory symptoms. A cough, although usually present, can be relatively insignificant in the total clinical picture. This diagnostic problem applies particularly to atypical pneumonia but can occur with bacterial pneumonia, especially lobar pneumonia.

Community-acquired pneumonia^12,14

CAP occurs in people who are not or have not been in hospital recently, and who are not institutionalised or immunocompromised. The choice of antibiotic is initially empirical. CAP is usually caused by a single organism, especially Streptococcus pneumoniae, which is now becoming resistant to antibiotics.¹⁵ Treatment is usually for 5–10 days for most bacterial causes, 2 weeks for Mycoplasma or Chlamydia infection and 2–3 weeks for Legionella.

Typical pneumonia

The commonest community-acquired infection is with Streptococcus pneumoniae (majority), now becoming resistant to antibiotics, Haemophilus influenzae¹⁵ (mainly in COPD), M. pneumoniae (young adults), Klebsiella pneumoniae.

• Often history of viral respiratory infection

• Rapidly ill with high temperature, dry cough, pleuritic pain, rigors or night sweats

• 1–2 days later may be rusty-coloured sputum

• Rapid and shallow breathing follows

• Examination: focal chest signs, consolidation

• Investigations: CXR, sputum M&C, oxygen saturation, specific tests/serology, PCR

• Complications: pleural effusion, empyema, lung abscess, respiratory failure

The atypical pneumonias

Refer to CHAPTER 29.

• Fever, malaise

• Headache

• Minimal respiratory symptoms, non-productive cough

• Signs of consolidation absent

• Chest X-ray (diffuse infiltration) incompatible with chest signs

• Virus, e.g. influenza

• Mycoplasma pneumoniae—the commonest:

  • – adolescents and young adults

  • – treat with:

    • roxithromycin 300 mg (o) daily

    • or

    • doxycycline 100 mg bd for 14 days

• Legionella pneumophila (legionnaire disease):

  • – related to cooling systems in large buildings

  • – incubation 2–10 days

Diagnostic criteria include:

• prodromal influenza-like illness

• a dry cough, confusion or diarrhoea

• very high fever (may be relative bradycardia)

• lymphopaenia with moderate leucocytosis

• hyponatraemia

Patients can become prostrate with complications. Treat with:

• azithromycin IV (first line) or erythromycin (IV or oral)

• plus (if very severe)

• ciprofloxacin or rifampicin

• Chlamydia pneumoniae:

  • – similar to Mycoplasma

• Chlamydia psittaci (psittacosis):

  • – treat with doxycycline, roxithromycin or erythromycin

• Coxiella burnetti (Q fever):

  • – treat with doxycycline 200 mg (o) statim then 100 mg daily for 14 days

Antibiotic treatment according to severity^11,12

This is usually empirical.

Mild pneumonia

This does not require hospitalisation.

• amoxycillin/clavulanate 875/125 mg (o) 12-hourly

• for 5–7 days or amoxycillin 1 g 8-hourly

• especially if S. pneumoniae isolated or suspected

• plus (especially if atypical pneumonia suspected)

• roxithromycin 300 mg (o) daily for 5 days or doxycycline 100 mg bd for 5 days

Moderately severe pneumonia

This requires hospitalisation (see Guidelines box for severe pneumonia and hospital admission). Monitor with CXR; oximeter (keep P_aO₂ ≥ 94%).

• Neonates

• Age over 65 years

• Coexisting illness

• High temperature: >38°C

• Clinical features of severe pneumonia

• Involvement of more than one lobe

• Inability to tolerate oral therapy

  • benzylpenicillin 1.2 g IV 4–6 hourly for 7 days

  • or

  • procaine penicillin 1.5 g IM daily (drugs of choice for S. pneumoniae) plus doxycycline

  • or

  • ceftriaxone 1 g IV daily for 7 days (in penicillin-allergic patient)

• If not so severe and oral medication tolerated, can use amoxycillin/clavulanate or cefaclor or doxycycline

• In tropical regions use a different regimen (refer to eTG)

• If atypical pneumonia, use doxycycline, erythromycin or roxithromycin

Severe pneumonia

The criteria for severity (with increased risk of death) are presented in the box on Guidelines for severe pneumonia and hospital admission.^14,15,16 The CURB-65 score indicates severity (Confusion, Urea > 7 mmol/L, Respiratory rate ≥30/min, BP <90/60 mmHg, Age ≥65).¹⁷

• azithromycin 500 mg IV daily (covers Mycoplasma, Chlamydia and Legionella)

• plus

• cefotaxime 1 g IV 8-hourly

• or

• ceftriaxone 1 g IV daily

• add

• flucloxacillin for Staphylococcus aureus

Clinical features

• Tachypnoea, expiratory grunt

• Possible focal chest signs

• Diagnosis often only made by chest X-ray

Pathogens

• Viruses are the most common cause in infants.

• Mycoplasma is common in children over 5 years.

• S. pneumoniae is a cause in all age groups.

• Pathogens are difficult to isolate—may need blood culture.

Treatment

Depends on age and tropical vs non-tropical. Almost all those under 48 months should be admitted to hospital. Indicators for hospital admission are shown in the box.

• Minimal handling

• Careful observations including pulse oximetry

• Attend to hydration

• Antibiotics indicated in all cases. Refer to guidelines for 5 years and older¹²

  Mild (general guidelines only):¹⁶

  • amoxycillin (o) or roxithromycin (o)

  Moderate:

  • benzylpenicillin IV + roxithromycin (o) or doxycycline (o)

  Severe:¹⁵

  • ceftriaxone IV or cefotaxamine IV ± azithromycin (o)

Note: Refer to eTG for various age groups and tropical regions.

A cough associated with a viral respiratory infection should last no more than 2 weeks. If it does, it is termed persistent. A cough lasting 2 months or more is defined as a chronic cough. A cough that lasts longer than 3–4 weeks requires scrutiny. TABLE 42.3 includes some causes of chronic cough.

A chronic cough can be divided into productive and non-productive. If productive, the presence of pus is significant, as purulent sputum usually means bacterial infection in the bronchi and/or sinuses.⁴ The main organisms are Haemophilus influenzae (the most common), S. pneumoniae and Moraxella. Such infections are most susceptible to amoxycillin or amoxycillin/clavulanate or parenteral cephalosporins.

Non-productive cough

Some of the many causes of a non-productive cough are included in TABLE 42.1 and more than one may be operative in a patient simultaneously; for example, an allergic snorer with oesophageal reflux taking an ACE inhibitor for hypertension may have a viral respiratory infection.⁴ It has been shown that a non-productive or irritating cough is usually caused by persistent stimulation of irritant receptors in the trachea and major bronchi, and may result in the production of small amounts of mucoid sputum.

Investigations to be considered in intractable chronic cough include a chest X-ray, spirometry, CT scan of the thorax (searching in particular for a tumour) and ambulatory oesophageal pH monitoring.

If bronchial hyper-responsiveness is proven, a trial of inhaled or oral corticosteroids can be used in these patients.⁵

Gastro-oesophageal reflux

This common condition is the most likely cause of a persistent, non-productive cough in an apparently well patient with a history of reflux. Recent studies utilising 24-hour ambulatory oesophageal pH monitoring have demonstrated that in patients with persistent unexplained cough the predominant cause is asymptomatic gastro-oesophageal reflux.^4,5 In the absence of evidence of aspiration, the cough is considered to be due to stimulation of a distal oesophageal-tracheobronchial reflex. Other studies have established a relationship between bronchial asthma and reflux or swallowing disorders whereby microaspiration can initiate an inflammatory response in the airways.

Indications for 24-hour ambulatory oesophageal pH monitoring in chronic cough include:

• unexplained chronic cough after clinical assessment

• symptomatic gastro-oesophageal reflux

• chronic cough with known aetiology unresponsive to therapy

If reflux is proven or suspected, treat with routine conservative anti-reflux measures and at least a 4-week trial of histamine H₂-receptor antagonists. If cough persists, refer for further evaluation.⁵

If all investigations and treatment trials (including anti-reflux and corticosteroids) prove unrewarding, a trial of ipratropium bromide both nebulised (500 mcg, qid) and to a lesser degree metered dose inhaler (4 × 20 μg puffs qid) has been found to be effective.^5,17

However, for patients with idiopathic chronic cough it is important to provide ongoing interest and support, and not eventually to dismiss them as ‘just a cough’.

Bronchial carcinoma

Lung cancer accounts for 25% of cancer deaths in men and 24% of cancer deaths in women (rapidly rising), with cigarette smoking being the most common cause of lung cancer in both sexes.¹¹ It is also the most common lethal cancer in both sexes in Australia. Bronchial carcinoma accounts for over 95% of primary lung malignancies. The prognosis is poor—the 5-year overall survival is 12–14%.¹⁸ The mesothelioma incidence continues to rise.

Clinical features

• Most present between 50 and 70 years (mean 67 years)

• Only 10–25% asymptomatic at time of diagnosis⁹

• If symptomatic—usually advanced and not resectable

• Cough (42%)

• Chest pain (22%)

• Wheezing (15%)

• Haemoptysis (7%)

• Dyspnoea (5%)

• Anorexia, malaise

• Weight loss—unexplained

• Unresolved chest infection

• Hoarseness

• Symptoms from metastases

The possible physical findings are summarised in FIGURE 42.3.

Investigations

• Chest X-ray

• Sputum cytology

• CT scanning

• Fibre-optic bronchoscopy

• PET scanning

• Fluorescence bronchoscopy (helps early detection)

• Tissue diagnosis where possible

Note: Based on a 2003 Cochrane review, no proven effect of any screening for asymptomatic patients.

Causes of a solitary pulmonary nodule on X-ray are presented in TABLE 42.7.

Management

Refer to a respiratory physician to determine the type of cancer. They are usually classified as small cell lung (oat cell) poorly differentiated cancer (15–20% incidence) (SCLC) and non-small cell lung cancer (NSCLC), which includes squamous cell carcinoma, adenocarcinoma and large cell carcinoma (approximately 20–30% of each). The main aim of management is a curative resection of NSCLC in those who can benefit from it. Surgery is not an option for SCLC since it metastasises so rapidly (80% have metastasised at the time of diagnosis).¹⁴ Chemotherapy is suitable for the deadly SCLC but currently only extends life expectancy from 3–20 months (at best). It also has an important place in treating NSCLC. The main role of radiotherapy is palliative.

Mesothelioma

Mesothelioma is a malignant tumour of mesothelial cells usually at the pleura. It is associated with prior asbestos exposure, possibly decades earlier (90% report exposure).

Clinical features include chest pain, dyspnoea, weight loss and recurrent pleural effusions. Diagnosis is based on imaging and on histology after pleural biopsy. Prognosis is poor and treatment is palliative support.

Bronchiectasis

Bronchiectasis is dilatation of the bronchi when their walls become inflamed, thickened and irreversibly damaged, usually after obstruction followed by infection. Predisposing causes include whooping cough, measles, TB, inhaled foreign body (e.g. peanuts in children), bronchial carcinoma, cystic fibrosis and congenital ciliary dysfunction (Kartagener syndrome). The left lower lobe and lingula are the commonest sites for localised disease.

Clinical features

• Chronic cough—worse on waking

• Mild cases: yellow or green sputum only after infection

• Advanced:

  • – profuse purulent offensive sputum

  • – persistent halitosis

  • – recurrent febrile episodes

  • – malaise, weight loss

• Episodes of pneumonia

• Sputum production related to posture

• Haemoptysis (blood-stained sputum or massive) possible

Examination

• Clubbing

• Coarse crackles over infected areas (usually lung base)

• Other respiratory signs are given in TABLE 49.6 (see CHAPTER 49).

Investigations

• Chest X-ray (normal or bronchial changes)

• Sputum examination: for resistant pathogens and to exclude TB

• Cytology: to rule out neoplasia

• Main pathogens: Streptococcus pneumoniae, Pseudomonas aeruginosa, Haemophilus influenzae (commonest), Staphylococcus aureus

• CT scan: can show bronchial wall thickening—high-resolution CT scan is the new gold standard for diagnosis

• Spirometry

• Bronchograms: very unpleasant and used only if diagnosis in doubt or possible localised disease amenable to surgery (rare)

Management²⁰

• Explanation and preventive advice.

• Postural drainage (e.g. lie over side of bed with head and thorax down for 10–20 minutes three times a day).

• Antibiotics for acute exacerbations according to organism—it is important to eradicate infection to halt the progress of the disease. Amoxycillin 500 mg (o) tds for 14 days or doxycyclin 200 mg (o) daily (if child ≥8 years) is recommended for first presentation.²⁰ Avoid long-term use.

• Bronchodilators, if evidence of bronchospasm.²¹

Although cough is a feature, pulmonary TB may be symptomless and detected by X-ray screenings.⁸ (Refer to CHAPTER 29.)

Symptomatic treatment of cough should be reserved for patients who have acute self-limiting causes of cough, especially an acute viral infection. There are many cough mixtures available and the major constituents of these mixtures are shown in TABLE 42.8.⁸ The recommended mixture should be tailored to the patient’s individual requirements. These mixtures should be used only in the short term.²⁰ Cough medicines are generally not recommended in children. The Therapeutic Guidelines Ltd recommend that cough and cold medicines, especially cough suppressants, antihistamines and related products, should not be given under 6 years. Consider sucrose and glycerol syrup (a demulcent).²¹

Strategies recommended to manage chronic cough in adults include:²¹

• sedating antihistamine at night

• PPIs because recurrent coughing causes acid reflex and vice versa

• low-dose inhaled corticosteroid

Short term: codeine phosphate 25–30 mg (o) every 3–6 hours.

If intractable: 2 mL lignocaine 2% via nebuliser, for 5–10 minutes up to 4 times daily for up to 7 days.

• Patients in whom bronchoscopy is necessary to exclude bronchial carcinoma

• Persistent hoarseness in a patient who requires expert laryngeal examination

• Evidence of pulmonary TB

Hand-out sheets from Murtagh’s Patient Education 7th edition:

• Common cold

• Croup

• Influenza

• Pneumonia