SPOTTERS MEDICINE

 

CLUBBING            

   

 

🔹 Definition:

Clubbing is a bulbous enlargement of the distal phalanges of fingers and toes due to proliferation of connective tissue beneath the nail bed.

---

🔹 Mechanism / Pathophysiology:

• Exact mechanism is unclear
• Proposed theories include:
• Platelet-derived growth factor (PDGF) from megakaryocytes
• Vascular hyperplasia and connective tissue proliferation
• Increased blood flow and capillary permeability in nail bed

---

🔹 Grades of Clubbing:

1.  Grade 1 – Fluctuation and softening of nail bed

2.  Grade 2 – Loss of normal Lovibond angle (<160° → >180°)

3.  Grade 3 – Increased curvature (drumstick appearance)

4.  Grade 4 – Hypertrophic osteoarthropathy (joint pain, periostitis)

---

🔹 Clinical Signs:

• Loss of Lovibond angle
• Spongy nail bed
• Schamroth's window test: obliteration of diamond-shaped window when fingers are opposed

---

🔹 Causes of Clubbing:

🔸 Pulmonary Causes:

• Lung cancer (bronchogenic carcinoma)
• Bronchiectasis
• Pulmonary tuberculosis
• Lung abscess
• Cystic fibrosis

🔸 Cardiovascular Causes:

• Cyanotic congenital heart diseases (e.g., Tetralogy of Fallot)
• Infective endocarditis

🔸 Gastrointestinal Causes:

• Inflammatory bowel disease (Crohn's, ulcerative colitis)
• Liver cirrhosis (esp. biliary)
• Malabsorption syndromes (e.g., celiac disease)

🔸 Other:

• Thyroid acropachy (in Graves’ disease)
• Hereditary clubbing

---

🔹 Differential Diagnosis:

• Pseudoclubbing (seen in arthritis)
• Nail deformities (onycholysis, koilonychia)

---

🔹 Investigations:

• Underlying cause identification:
• Chest X-ray, CT scan
• Echocardiogram
• Liver function tests
• Colonoscopy (if GI suspected)

---

🔹 Treatment:

• Clubbing is a sign, not a disease
• Treat the underlying cause (e.g., antibiotics for TB, surgery for lung cancer)

---

🔹 Prognosis:

• May reverse if underlying condition is cured (e.g., lung abscess)
• Permanent in chronic or irreversible diseases

---

DR.C.GANESAN M.D.

PROFESSOR OF MEDICINE