Clubbing

Defination:

• this is refers to the tissues at the base of the nails are thickened and the angle between the nails base and the adjacent skin of the finger is obliterated .

pathology:

• Hypervascularity & opening of anastomotic chennels in the nails .

Instruction by the examiner:

• Perform the general examination of this patient.
• Examine the hands or look at the fingers. What are your findings?

Proceed as follows:

• First look whether gross clubbing is present or not.
  
• If not, look carefully at the angle between nail and its base at the level of the observer’s eye(normal angle is 160°).
• Next, see the fluctuation at the nail bed.
• Place the corresponding opposite nails of both hands (normally, small gap is present. If clubbing, there is reduction or absence of the gap, called window sign or Schamroth sign).
• Look to see the convexity of nails from side-to-side.
•  In advance stage—drumstick or parrot-beak appearance.
• Always see hypertrophic osteoarthropathy—press the ends of ong bones (radius and ulna, tibia and fibula). Look at the face (patient winces due to pain).

 Grades or stages of clubbing

4 stages:

• Grade 1: Softening of nail bed (fluctuation is positive). It is due to proliferation of cells at nail base.
• Grade 2: Increased curvature of nails, which become convex and angle between the nail and its base is obliterated.
• Grade 3: Increase pulp tissue, resulting in drumstick or parrot beak or both.
• Grade 4: Hypertrophic osteoarthropathy.

Causes  of Clubbing:

1. Respiratory:

•  Bronchial carcinoma.
•  Suppurative lung disease (bronchiectasis, lung abscess, empyema thoracis).
•  DPLD (ILD).
•  Pulmonary TB (in advanced stage with fibrosis).
•  Pleural mesothelioma.
•  Pulmonary arteriovenous fistulae.
•  Cystic fibrosis.

2. Cardiac:

• Cyanotic congenital heart disease (Fallot’s tetralogy).
• Infective endocarditis (SBE).
•  Atrial myxoma.

3. GI tract:

• Inflammatory bowel disease (Crohn’s disease, Ulcerative colitis).
• Polyposis coli (rarely).

4. Hepatobiliary:

• Chronic liver disease (e.g., Cirrhosis of liver).
• Primary biliary cirrhosis.

5. Miscellaneous:

• Familial (rare).
• Idiopathic.
• Congenital.
• Thyrotoxicosis (called thyroid acropachy).

Q: What are the causes of unilateral clubbing?

A: As follows:

• Pre-subclavian coarctation of aorta.
• Arteriovenous fistulae of brachial vessels.
• Aneurysm of subclavian artery.
• Pancoast tumour.
• Erythromelalgia.

Q: What are the causes of clubbing of single finger? (unidigital clubbing)

A: As follows:

• Repeated local trauma (commonest cause).
• Chronic tophaceous gout.
• Sarcoidosis.
• Median nerve injury.

Q: What are the causes of clubbing with cyanosis?

A: As follows:

• DPLD (ILD).
•  Cyanotic heart disease (Fallot’s tetralogy).
•  Eisenmenger’s syndrome.
• Cystic fibrosis.
• Bilateral extensive bronchiectasis.

Q: What is pseudoclubbing? What are the causes?

A: It means, fingers or toes look like clubbing, but there is no soft tissue proliferation or increased curvature

of the nails. It is due to resorption of subperiosteal bone of terminal phalanges. Causes are:

• Systemic sclerosis.
• Hyperparathyroidism.

investigations:

•  Full blood count.
• Chest X-ray.
• USG of whole abdomen.
•  Echocardiography.
•  Other—according to cause (barium enema, follow through, colonoscopy for inflammatory bowel disease, liver function test).