In the bi-monthly CME & Quiz series, Dr. Amdekar delivers a lesson on cough with the help of various case scenarios. 

To begin, take the quiz below to test your knowledge.

---

Cough is a localising symptom, unlike fever. It is often a primary respiratory disease though may be secondary to cardiac, GI or neurological disorder. Hence one must start with anatomical diagnosis – which system is involved and further which part of the system is affected – it is microanatomy of the disease.

Significant cough localises disease to larynx, trachea or bronchi. In other areas of affection in the respiratory tract, cough is mild and often accompanied with other symptoms such as chest pain in pleural disease, acute breathlessness in pneumonia or bronchiolitis. Palpitation and breathlessness suggest cardiac disease while chocking episode reflects probable gastro-oesophagal reflux or neurological disorder.

Of course, if one fails to localise anatomy of the disease, it may be psychogenic. Unless microanatomy is known, one can’t proceed to pathology. Most common pathological processes involved in the production of cough are inflammation and allergy. Acute inflammation is characterised by fever while chronic inflammation presents with worsening systemic symptoms such as loss of weight and appetite.

Allergy presents with sudden onset of cough that may also disappear suddenly but often would recur. Besides, there is often a personal or family history of allergy. Respiratory allergy affects the entire system so also in case of viral infection while the bacterial infection is mostly localised to a part of the system and not generalised. Thus, probable aetiology also can be guessed.

---

Case based studies

Case 1

A 2-year-old child presented with fever followed the next day with cold and cough. Cough was severe with watery discharge from the nose. There was no past history of a similar disease.

Physical examination revealed febrile child with coryza but not looking very sick. The chest was clear. Fever suggests infection and cough denotes airway disease along with the involvement of the nose as well. So this is generalised involvement of airways. This is typical of viral infection and so does not need any antibiotic or laboratory tests.

Fever settled down within 3 days with paracetamol. Cold and cough also got better over the next 2 days. In case of watery nasal secretions, one needs to wipe them and in case of nose block, instil normal saline drops in the nostrils. It helps to unblock the nose. Cough syrups are of no much use.

Onset with fever followed by cold and cough and fever settling down within 3 days followed by natural relief of cold and cough is typical of acute viral respiratory infection.

One could have guessed the diagnosis in this child even on day 2 of illness and so could have counselled parents about the benign nature of the disease not needing any medicines. Viral respiratory infections are contagious and so family history helps to consider such a diagnosis.

Case 2

A 2-year-old child presented with fever followed the next day with cold and cough. Cough was severe with watery discharge from the nose. There was a past history of recurrent episodes of cough often without fever. However, there was no history of allergy in the family. Physical examination did not reveal any localising signs.

Onset of disease with fever suggests infection with generalised involvement of airways affecting nose down to bronchi. So this is similar to the previous case. However, in this child, fever subsided on its own within the next 2 days but cough worsens and continued for the next two weeks.

Physical examination during this period continued to show no other signs. As fever had disappeared, infection was definitely controlled. If so, why did cough continue for such a long time?

This is referred to as hyper-reactive airway disease. It means this child is susceptible to recurrent episodes of cough that could be triggered by either viral infection or allergy. It is evident in history itself as this child had recurrent episodes of cough in the past. Cough did settle down by itself though it lasted too long.

Here is the need for proper counselling rather than trying some medicines. Of course, there is no question of antibiotic in this child nor does this child deserve laboratory tests or chest x-ray. Inhaled bronchodilators help.

This child looked similar to the previous case except for the past history of recurrent cough. This child has dual disease – a viral infection that has triggered pre-existing hyper-reactive airway disease.

One could have guessed right on day 2 of illness that this child would continue to cough for longer time well after the disappearance of fever. Parents would be warned about long-lasting cough but would not need any tests or antibiotics.

In fact, more the cough, lesser is the need for chest x-ray or antibiotics. Such a child may get temporary relief from cough by inhalation therapy with bronchodilators such as beta-2 agonists.

Case 3

A 6-year-old child presented with high fever, thick yellow nasal secretions and cough for the last two days. Past history revealed repeated episodes of cold and cough since the age of 2 years, at times accompanied by high fever, treated with antibiotics. There was a history of allergy in the family.

Physical examination showed a highly febrile child, looking sick, adenoid facies, (open mouth suggesting chronic obstruction to breathing through nostrils due to enlarged adenoids), ears normal and no localising findings in the chest.

High fever in a sick child favours probable bacterial infection. However, in the background is hyper-reactive airways disease that is allergic as evident by a family history of allergy in a child with repeated episodes of cold and cough.

So this child needs to be treated with antibiotic for the present but once the infection is controlled, he should be treated for allergic rhinosinusitis. Amoxicillin with or without clavulanic acid is the drug of choice for respiratory infections.

Persistent nasal discharge for more than two weeks is likely to represent sinusitis – referred to as rhinosinusitis. Once the secretions remain stagnated in sinuses, bacterial infection supervenes. So, this child has a dual disease - an allergic respiratory disease with a secondary bacterial infection.

Case 4

A 4-year-old child presented with high fever and a mild cough. Fever was high at onset with a mild response to paracetamol and high fever would recur every 4-5 hours as the effect of paracetamol would wear off.

The child always remained sick during the interfebrile period. Cough was mild and not disturbing the child. Physical examination did not reveal any abnormality except a sick looking child.

At this juncture, one is expecting the bacterial infection to localise mostly in lung parenchyma as suggested by a mild cough. Mild cough is also a feature of bronchiolitis, pleural or interstitial disease. Acute bronchiolitis presents with upper respiratory symptoms and often with mild fever while the acute interstitial infection is often viral and so involves the entire respiratory system with significant cough and so, both these diseases are unlikely in this child.

Absence of chest pain rules out pleural disease. Though at times pleura may be involved in case of pneumonia and such a child may present with chest pain. Hence, even on day 2 of illness, bacterial pneumonia is most likely and one must watch carefully for further progress.

A day later, he developed mild breathlessness and now a diagnosis of pneumonia is confirmed by chest x-ray and CBC showing neutrophilic leucocytosis. Amoxicillin with clavulanic acid was started and the child started responding with relief from breathlessness and fever was also in control. Though cough worsened by this time.

Does it suggest complication or drug-resistant infection? Neither of the two. In fact, as pneumonia starts improving, cough often worsens as inflammatory exudate liquefies and has to be expelled through airways. It results in temporary worsening of cough. It is nature’s attempt to get rid of exudate to ensure complete healing.

There was no need to change medicines and antibiotic was continued for 7 days with full recovery. There was no need of cough syrup as well.

Diagnosis of bacterial pneumonia can be suspected even prior to the development of clinical signs of pneumonia as early as day 2-3 and appropriate actions can be taken.

It is also important to anticipate the course of events during successful therapy and worsening of cough in such a case is an anticipated event and not a complication. Parents could be forewarned about worsening cough at the time of improvement that is self-limiting.

Case 5

An 8-year-old child presented with mild fever and cough for 2 days. Physical examination did not reveal any abnormality. At this stage, there is no clue to diagnosis, but acute infection seems unlikely due to onset with low-grade fever and it is best to watch further progress without any tests or medicines. It is safe to wait as the child is not sick looking.

The child continued to run a mild fever for the next 10 days but the cough was worsening. So, this is a subacute infection of the respiratory tract with gradual worsening.

Physical examination at this stage showed localised crepitations on the right side of the chest and child had lost one kg of weight. Diagnosis of tuberculosis was possible and was proved with chest x-ray and confirmed with GeneXpert.

This child was treated with four drug treatment (HRZE) for two months and HRE for the next four months. The child showed improvement within 2-3 weeks, though treatment must be completed for 6 months.

The cough may be mild if lung parenchyma alone is involved but may be severe if airways are also affected along with lung parenchyma.

So also fever in tuberculosis may be mild or high depending on the immune status of the child and type of pathology of the disease. Mycoplasma infection also involves airways and lung parenchyma both though it is usually an acute infection.

Case 6

A 4-year-old child presented with mild fever and dry cough but over the next five days, cough started worsening though fever disappeared. Physical examination at this stage did not reveal any abnormality.

It is clear that this is upper respiratory tract infection as evident by dry cough but further progress suggests worsening the local condition in upper airways without deterioration of systemic symptoms such as fever.

On direct questioning, two other family members were reported to be suffering from similar cough for last one month. So this is a highly infectious disease and a diagnosis of pertussis – whooping cough was made. He was treated with Macrolide. It took another week before he got well.

Pertussis runs through the natural course for 4-6 weeks unless diagnosed in the first week and treated promptly. Bacteriological confirmation is not easy and so diagnosis is clinical, based on circumstantial evidence of severe worsening cough with mild or no fever and presence of positive family history.

Even in the case of late diagnosis, the antibiotic is a must as it prevents the spread of infection to others though no benefit accrues to a patient.

Case 7

A 2-year-old child presented with severe cough for the last 2 days. There were no other complaints. There was no past or family history of allergy. Physical examination did not reveal any obvious abnormality.

Acute onset of severe cough without fever rules out infection and suggests either mechanical problem or allergy. As there is no history suggestive of an allergy, it is likely to be a mechanical problem.

On direct questioning, parents recalled that cough started all of a sudden in a minute while he was eating. It gave away the diagnosis of an inhaled foreign body. It was a piece of groundnut that was removed through the bronchoscope.

An inhaled foreign body may not be picked-up by clinical examination, especially if it is lodged in the smaller bronchial segment and also missed by chest x-ray as the vegetable foreign body is not visible on x-ray.

History of onset of any symptom is important. When cough starts suddenly, it is either mechanical (pneumothorax besides inhaled foreign body) or vascular (pulmonary embolism), one that presents over a few minutes or hours is likely to be an allergy. Infection presents with localising symptom over a few days.

Case 8

A 8-year-old child was seen for cough going on for the last 6 months. There were no other symptoms. Physical examination did not show any abnormality. Several tests and trials with medicines including antibiotics, cough syrups and inhalers had failed to control cough.

Finally, he was advised to undergo bronchoscopy that he refused. What was missing? On detailed questioning, it was clear that he was never disturbed by cough during sleep and play activities. Besides he was eating well and had gained weight during the last 6 months.

So, the diagnosis was a habit cough. Such a child often would oblige by controlling cough, if you insist that he should not cough while you examine him so that you would be able to diagnose his problem.

Habit cough is due to stress. Treatment is to probe into details to find out what must be bothering him that manifests with such a functional disorder.

---

You can read about the basics of cough and why most drugs fail to suppress it in the first part here.

Disclaimer- The views and opinions expressed in this article are those of the author's and do not necessarily reflect the official policy or position of M3 India.