Dahl's sign

Dahl's sign
Synonyms	Carpet burn sign
Pronounce	N/A
Specialty	Pulmonology, Cardiology
Symptoms	Hyperpigmented patches on the skin of the knees and elbows
Complications	N/A
Onset	N/A
Duration	N/A
Types	N/A
Causes	Chronic obstructive pulmonary disease (COPD), prolonged kneeling
Risks	Chronic bronchitis, Emphysema
Diagnosis	Clinical examination
Differential diagnosis	Acanthosis nigricans, Contact dermatitis
Prevention	N/A
Treatment	Management of underlying COPD
Medication	N/A
Prognosis	Depends on the management of the underlying condition
Frequency	Common in patients with advanced COPD
Deaths	N/A

Dahl's sign is a medical sign used in the diagnosis of chronic obstructive pulmonary disease (COPD). It is named after the American physician, Dr. Loren C. Dahl, who first described it in 1963.

Description

Dahl's sign is a physical finding that is present in some patients with COPD. It is characterized by the presence of a horizontal crease or fold across the earlobe. This sign is thought to be caused by the repeated downward pull of the earlobe due to the weight of the oxygen tubing used in the treatment of COPD.

Clinical significance

While Dahl's sign is not a definitive diagnostic tool for COPD, it can be a useful clue in the clinical setting. It is often seen in patients with severe COPD who have been on long-term oxygen therapy. However, it can also be present in patients with other chronic lung diseases.

Limitations

The presence of Dahl's sign does not necessarily indicate the severity of COPD. It is also not specific to COPD and can be seen in other conditions such as pulmonary fibrosis and pulmonary hypertension. Therefore, it should be used in conjunction with other clinical findings and diagnostic tests to confirm a diagnosis of COPD.

See also

• Chronic obstructive pulmonary disease
• Medical sign
• Oxygen therapy