Cough

A 68 year old retired joiner presents with a three month history of dry cough. It is present throughout the day. He has not coughed up any blood.  He denies any chest pain or breathlessness. He has not lost weight.  He smokes 20 cigarettes per day. He also has hypertension.

Cough is the reflex response to an irritant anywhere in the respiratory tract from the lungs to pharynx. It is defined as acute <3weeks or chronic >3 weeks. It is one of the commonest respiratory symptoms with multiple causes.  There is often an overlap with shortness of breath and sore throat.

Acute cough <3 weeks

• Upper respiratory tract infection – the commonest cause of acute cough. E.g. pharyngitis, common cold.
• Lower respiratory tract infection – e.g. pneumonia, acute bronchitis.
• Acute exacerbation of COPD/Asthma/bronchiectasis
• Inhalation of foreign body   

Chronic >3 weeks 

• Exposure to cigarette smoke – active or passive
• Post-infective cough – dry intermittent cough post URTI/bronchitis.  
• Post-nasal drip – secondary to nasal infection or allergy. Persistent cough, worse in the morning. Dry or purulent. 
• Asthma – Diurnal variation of dry cough. Wheeze.
• Gastro-oesophageal reflux – persistent dry cough. Can be present without other symptoms.
• ACE inhibitors –persistent dry cough after starting medication.
  
• Lung cancer – persistent cough is the most common presenting symptoms. May be associated with haemoptysis, weight loss and breathlessness.  
• Bronchiectasis – recurrent LRTI with purulent sputum and cough. 
• TB – persistent cough associated with night sweats and weight loss. 
• Whooping cough – Increasing prevalence. Persistent spasms of coughing, often precipitated by exercise and change in temperature. Cough can last for months afterwards.

Assessment

 The aim is to make a diagnosis by understanding the epidemiology and pattern of cough, making sure to rule out serious pathology. 

Pattern of cough

• Acute onset versus chronic onset
• Dry versus purulent
• Time of day
• Precipitation factors e.g. exercise, medication
• Infectious contacts

Associated Features

• Fever
• Night sweats
• Shortness of breath
• Haemoptysis
• Weight loss

Lifestyle factors

• Medication
• Smoking
• Occupation including asbestos exposure
• Young children

Red flags

Weight Loss >3kg, cough persisting > 3 weeks. Haemoptysis. Finger clubbing. Night sweats.

Examination and investigation

Diagnosis of cough is usually made on clinical history. Examination is essential to identify important signs and should include:

• Temperature
• Pulse
• Oxygen saturations
• Fingers– for clubbing
• Cervical lymph nodes
• Throat and ear examination
• Chest examination
• Peak flow measurement if asthma suspected

In the vast majority of cases examination will identify the cause. CXR is required in all patients who have had a cough lasting over three weeks. If the CXR is normal and there are persistent signs suggestive of lung cancer, such as haemoptysis, the patient should be referred to respiratory clinic. Sputum microscopy, culture and sensitivity can be useful in persistent purulent coughs and for guiding treatment in bronchiectasis.  Spirometry is used if asthma/COPD is suspected  

Diagnosis – This should be made taking history and examination into account.

Acute cough

Upper respiratory tract infection – E.g. pharyngitis, common cold. Cough with or without sputum lasting about 7-10 days followed by a dry irritant cough, worse with exercise and falling asleep. May be malaise and fever. Pain and discharge is localised to throat, ears, nose and/or sinuses.

Lower respiratory tract infection – e.g. pneumonia, acute bronchitis. Cough with or without sputum. General malaise. Increased shortness of breath. Crackles on auscultation in bronchitis. Pneumonia can also present with wheeze, pleuritic pain, dull percussion note, bronchial breathing and coarse crackles. 

Acute exacerbation of COPD/Asthma – see section on breathlessness.

Inhalation of foreign body – sudden onset, dry cough. Can be associated with stridor, reduced chest sounds on affected side and decreased breath sounds.  

Acute exacerbation of bronchiectasis – cough with purulent sputum, increasing breathlessness and wheeze.

Pertussis (Whooping cough) – Increasing prevalence. Persistent spasms of coughing, often precipitated by exercise and change in temperature. 

Chronic cough

• Exposure to cigarette smoke – dry cough worse in the morning.
• Post-infective cough – dry intermittent cough post URTI/bronchitis. Otherwise well, with normal examination. 
• Post-nasal drip – Persistent cough and throat clearing. May be associated with chronic sinusitis or allergic rhinitis. 
• Asthma – Wheeze, shortness of breath. Diurnal variation. Worse with exercise or exposure to allergens. Reduced peak flow during exacerbations.
• COPD – progressive breathlessness and chronic cough. Recurrent chest infections. 
• Gastro-oesophageal reflux – persistent dry cough. Can be worse on eating, talking or bending. Can be present without other symptoms.
• ACE inhibitors – dry persistent cough after starting medication
• Lung cancer – persistent cough is the most common presenting symptoms. May be associated with haemoptysis, weight loss and breathlessness, shoulder and/or chest pain, hoarseness, cervical or supraclavicular lymphadenopathy
• Bronchiectasis –recurrent LRTI with purulent sputum and cough. 
• TB – persistent cough and shortness of breath associated with night sweats and weight loss. Malaise and finger clubbing.
• Pertussis (Whooping cough) – Increasing prevalence. Persistent spasms of coughing, often precipitated by exercise and change in temperature. 

Management

Management depends on cause. Failure to respond to initial management should lead to consideration of alternative diagnoses. 

Acute cough

Consider admission if the patient has signs of serious illness, such as sepsis or oxygen saturations of less the 92%.  If not requiring admission:

• URTI – reassurance, ibuprofen or paracetamol for symptomatic treatment. Stop smoking. Safety netting. Usually do not require antibiotics as cause is often viral.  
• LRTI – depends on CRB-65 score. Acute bronchitis can be treated symptomatically if patient is well. Pneumonia is treated with antibiotics, currently in NHS Lothian amoxicillin or doxycycline. Strong worsening statement. 
• Asthma/COPD – see section on shortness of breath
• Inhalation of foreign body – refer as emergency
• Acute exacerbation of bronchiectasis – send sputum to lab from culture. Treat with antibiotics. Patients usually have advice in notes from respiratory of which antibiotic to use. If not a broad spectrum antibiotic such as amoxicillin is appropriate.
• Pertussis (whooping cough) – send blood for serology initially. If less than 21 days treat with antibiotics. Usually a macrolide. Avoid contact with unvaccinated children and advise work or nursery about illness.

Chronic cough  

• Smoking related cough – advise patients to stop smoking
• Post-infective – reassurance and advice that cough may take few more weeks to resolve  
• Post-nasal drip– treat with steroid nasal spray and advise may take at least three months to see an effect. 
• TB – Often picked up on X-ray. Refer urgently to infectious diseases or respiratory depending on local policy
• Pertussis (whooping cough) – >21 days antibiotic are not indicated and advise that cough may persist for a few more weeks. 
• Asthma/COPD– see section on breathlessness
• Gastro-oesophageal reflux disease (GORD) – see dyspepsia chapter  
• ACE-I– stop medication and change to ARB if clinically indicated. Cough usually resolves within a month. 
• Bronchiectasis – refer to respiratory for further management
• Lung cancer – urgent referral to respiratory. 

The patient had a normal examination and no red flags were identified. He had a CXR which was normal. His ACE-I was stopped and his cough disappeared over the next two weeks. He was started on losartan for his hypertension.

Exam preparation

• Explain to a patient the rationale behind not prescribing antibiotics for an upper respiratory tract infection.
• Discuss smoking cessation with a patient using motivational interviewing techniques.

References  

NICE Clinical knowledge summary – cough https://cks.nice.org.uk/cough

NICE guidelines on lung cancer referrals – https://pathways.nice.org.uk/pathways/lung-cancer 

Lothian Joint Formulary – guidance on medication http://www.ljf.scot.nhs.uk/Pages/default.aspx