9 year Old Boy With A Chronic History Of Cough And Diarrhea Is In The Clinic For A Routine Followup

A 9 year old male child is having a routine followup with his primary care physician when a voluntary medical student approaches this patient for clinical history and examination. The child's mother gives the history of the patient being always sick since the time when he was an infant. He suffers from repeated respiratory infections needing antibiotic for treatment. The patient also has repeated episodes of diarrhea and he looks young for his age with some degree of growth retardation.
On physical examination, the medical student found a very striking sign in the hands. The picture is shown below:

What is the sign seen in the above picture?
.
.
Clubbing of the fingers.

On the basis of history what is the Differential Diagnosis?

• Cystic Fibrosis
• Congenital heart disease.
• Celiac disease.
• Malabsorption disorder.

The above mentioned patient has cystic fibrosis.

Case Discussion:

Clubbing is defined as the changes that occur in the finger or toe nails caused by accumulation of soft tissue beneath the nail bed. This leads to loss of the normal angle between the nail fold and the nail bed. Clubbing may be present in varying degree of severity and is divided into following five stages:

1. Fluctuation and softening of the nail bed. 

2. Loss of normal < 165 degree angle between the nail bed and the fold.

3.  Increased convexity of the nail fold.

4. Thickening of the whole distal end of the finger (resembling a drumstick)

5. Shiny aspect and striation of the skin and the nail.

Causes: Finger and toe nail clubbing occurs due to certain underlying disease. These may include:

• Lung cancer
• Lung abscess
• Cystic fibrosis
• Congenital heart disease
• Bronchiectasis.
• Interstitial lung diseases
• Infective endocarditits.
• Cirrhosis of liver
• Celiac disease
• Dysentry
• Thyroid disorders
• Certain GI tract lymphomas. 
• Complicated tuberculosis.
• Malabsorption disorders
• Crohn's disease and Ulcerative colitis
• Idiopathic
• Familial.

Management: There is no specific treatment for nail clubbing. The sign should be taken as an indication of an underlying disorder and appropriated workup should be done and when the cause is identified , treatment and management should be directed towards the main disease.