Nail clubbing, also known as digital clubbing or clubbing, is a deformity of the finger or toe
nails associated with a number of diseases, mostly of the
heart
The heart is a muscular organ in most animals. This organ pumps blood through the blood vessels of the circulatory system. The pumped blood carries oxygen and nutrients to the body, while carrying metabolic waste such as carbon dioxide t ...
and
lungs
The lungs are the primary organs of the respiratory system in humans and most other animals, including some snails and a small number of fish. In mammals and most other vertebrates, two lungs are located near the backbone on either side of th ...
.
[Freedberg, et al. (2003). ''Fitzpatrick's Dermatology in General Medicine''. (6th ed.). McGraw-Hill. . ] When it occurs together with
joint effusion
A joint effusion is the presence of increased intra-articular fluid. It may affect any joint. Commonly it involves the knee.
Diagnostic approach
The approach to diagnosis depends on the joint involved. While aspiration of the joint is conside ...
s, joint pains, and abnormal skin and bone growth it is known as
hypertrophic osteoarthropathy
Hypertrophic osteoarthropathy is a medical condition combining clubbing and periostitis of the small hand joints, especially the distal interphalangeal joints and the metacarpophalangeal joints. Distal expansion of the long bones as well as pai ...
.
Clubbing is associated with
lung cancer
Lung cancer, also known as lung carcinoma (since about 98–99% of all lung cancers are carcinomas), is a malignant lung tumor characterized by uncontrolled cell growth in tissue (biology), tissues of the lung. Lung carcinomas derive from tran ...
, lung infections,
interstitial lung disease
Interstitial lung disease (ILD), or diffuse parenchymal lung disease (DPLD), is a group of respiratory diseases affecting the interstitium (the tissue and space around the alveoli (air sacs)) of the lungs. It concerns alveolar epithelium, pulmo ...
,
cystic fibrosis
Cystic fibrosis (CF) is a rare genetic disorder that affects mostly the lungs, but also the pancreas, liver, kidneys, and intestine. Long-term issues include difficulty breathing and coughing up mucus as a result of frequent lung infections. O ...
, or
cardiovascular disease
Cardiovascular disease (CVD) is a class of diseases that involve the heart or blood vessels. CVD includes coronary artery diseases (CAD) such as angina and myocardial infarction (commonly known as a heart attack). Other CVDs include stroke, h ...
.
[ Clubbing may also run in families,][ and occur unassociated with other medical problems.]
The incidence of clubbing is unknown; it was present in about 1% of people admitted to an internal medicine unit of a hospital.[ Clubbing has been recognized as a sign of disease since the time of ]Hippocrates
Hippocrates of Kos (; grc-gre, Ἱπποκράτης ὁ Κῷος, Hippokrátēs ho Kôios; ), also known as Hippocrates II, was a Greek physician of the classical period who is considered one of the most outstanding figures in the history of ...
.
Causes
Clubbing is associated with
* Lung disease:
** Lung cancer
Lung cancer, also known as lung carcinoma (since about 98–99% of all lung cancers are carcinomas), is a malignant lung tumor characterized by uncontrolled cell growth in tissue (biology), tissues of the lung. Lung carcinomas derive from tran ...
** Interstitial lung disease
Interstitial lung disease (ILD), or diffuse parenchymal lung disease (DPLD), is a group of respiratory diseases affecting the interstitium (the tissue and space around the alveoli (air sacs)) of the lungs. It concerns alveolar epithelium, pulmo ...
most commonly idiopathic pulmonary fibrosis
Idiopathic pulmonary fibrosis (IPF), or (formerly) fibrosing alveolitis, is a rare, progressive illness of the respiratory system, characterized by the thickening and stiffening of lung tissue, associated with the formation of scar tissue. It is ...
** Complicated tuberculosis
Tuberculosis (TB) is an infectious disease usually caused by '' Mycobacterium tuberculosis'' (MTB) bacteria. Tuberculosis generally affects the lungs, but it can also affect other parts of the body. Most infections show no symptoms, in ...
** Suppurative lung disease: lung abscess
Lung abscess is a type of liquefactive necrosis of the lung tissue and formation of cavities (more than 2 cm) containing necrotic debris or fluid caused by microbial infection.
This pus-filled cavity is often caused by aspiration, which may ...
, empyema
An empyema () is a collection or gathering of pus within a naturally existing anatomical cavity. For example, pleural empyema is empyema of the pleural cavity. It must be differentiated from an abscess, which is a collection of pus in a newly forme ...
, bronchiectasis
Bronchiectasis is a disease in which there is permanent enlargement of parts of the bronchi, airways of the lung. Symptoms typically include a chronic cough with sputum, mucus production. Other symptoms include shortness of breath, hemoptysis, co ...
, cystic fibrosis
Cystic fibrosis (CF) is a rare genetic disorder that affects mostly the lungs, but also the pancreas, liver, kidneys, and intestine. Long-term issues include difficulty breathing and coughing up mucus as a result of frequent lung infections. O ...
** Mesothelioma
Mesothelioma is a type of cancer that develops from the thin layer of tissue that covers many of the internal organs (known as the mesothelium). The most common area affected is the lining of the lungs and chest wall. Less commonly the lining ...
of the pleura
** Arteriovenous fistula or malformation
** Sarcoidosis
Sarcoidosis (also known as ''Besnier-Boeck-Schaumann disease'') is a disease involving abnormal collections of inflammatory cells that form lumps known as granulomata. The disease usually begins in the lungs, skin, or lymph nodes. Less commonly af ...
* Heart disease:
** Any disease featuring chronic hypoxia
Hypoxia means a lower than normal level of oxygen, and may refer to:
Reduced or insufficient oxygen
* Hypoxia (environmental), abnormally low oxygen content of the specific environment
* Hypoxia (medical), abnormally low level of oxygen in the tis ...
** Congenital cyanotic heart disease
A cyanotic heart defect is any congenital heart defect (CHD) that occurs due to deoxygenated blood bypassing the lungs and entering the systemic circulation, or a mixture of oxygenated and unoxygenated blood entering the systemic circulation. It is ...
(most common cardiac cause)
** Subacute bacterial endocarditis
** Atrial myxoma
A myxoma is a rare benign tumor of the heart. Myxomata are the most common primary cardiac tumor in adults, and are most commonly found within the left atrium near the valve of the fossa ovalis. Myxomata may also develop in the other heart chamber ...
(benign tumor)
** Tetralogy of Fallot
Tetralogy of Fallot (TOF), formerly known as Steno-Fallot tetralogy, is a congenital heart defect characterized by four specific cardiac defects. Classically, the four defects are:
*pulmonary stenosis, which is narrowing of the exit from the ri ...
* Gastrointestinal and hepatobiliary:
** Malabsorption
Malabsorption is a state arising from abnormality in absorption of food nutrients across the gastrointestinal (GI) tract. Impairment can be of single or multiple nutrients depending on the abnormality. This may lead to malnutrition and a variety ...
** Crohn's disease
Crohn's disease is a type of inflammatory bowel disease (IBD) that may affect any segment of the gastrointestinal tract. Symptoms often include abdominal pain, diarrhea (which may be bloody if inflammation is severe), fever, abdominal distension ...
and ulcerative colitis
Ulcerative colitis (UC) is a long-term condition that results in inflammation and ulcers of the colon and rectum. The primary symptoms of active disease are abdominal pain and diarrhea mixed with blood (hematochezia). Weight loss, fever, and a ...
** Cirrhosis
Cirrhosis, also known as liver cirrhosis or hepatic cirrhosis, and end-stage liver disease, is the impaired liver function caused by the formation of scar tissue known as fibrosis due to damage caused by liver disease. Damage causes tissue repai ...
, especially in primary biliary cholangitis
Primary biliary cholangitis (PBC), previously known as primary biliary cirrhosis, is an autoimmune disease of the liver. It results from a slow, progressive destruction of the small bile ducts of the liver, causing bile and other toxins to build ...
** Hepatopulmonary syndrome
In medicine, hepatopulmonary syndrome is a syndrome of shortness of breath and hypoxemia (low oxygen levels in the blood of the arteries) caused by vasodilation (broadening of the blood vessels) in the lungs of patients with liver disease. Dyspnea ...
, a complication of cirrhosis
* Others:
** Graves' disease
Graves' disease (german: Morbus Basedow), also known as toxic diffuse goiter, is an autoimmune disease that affects the thyroid. It frequently results in and is the most common cause of hyperthyroidism. It also often results in an enlarged thyr ...
(autoimmune hyperthyroidism) – in this case it is known as ''thyroid acropachy
Acropachy is a dermopathy associated with Graves' disease. It is characterized by soft-tissue swelling of the hands and Nail clubbing, clubbing of the fingers. Radiographic testing, Radiographic imaging of affected extremities typically demonstrat ...
''
** Familial and hereditary clubbing and "pseudoclubbing" (people of African descent often have what appears to be clubbing)
** Vascular anomalies of the affected arm such as an axillary artery aneurysm
Axillary means "related to the axilla (armpit)" or "related to the leaf axils".
"Axillary" may refer to: Biology
* Axillary artery
* Axillary border
* Axillary fascia
* Axillary feathers
* Axillary hairs
* Axillary lines
* Axillary lymph nodes
* ...
(in unilateral clubbing)
Nail clubbing is not specific to chronic obstructive pulmonary disease
Chronic obstructive pulmonary disease (COPD) is a type of progressive lung disease characterized by long-term respiratory symptoms and airflow limitation. The main symptoms include shortness of breath and a cough, which may or may not produce ...
(COPD). Therefore, in patients with COPD and significant degrees of clubbing, a search for signs of bronchogenic carcinoma (or other causes of clubbing) might still be indicated.[ A congenital form has also been recognized.]
Hypertrophic pulmonary osteoarthropathy
A special form of clubbing is hypertrophic pulmonary osteoarthropathy
Hypertrophic osteoarthropathy is a medical condition combining clubbing and periostitis of the small hand joints, especially the distal interphalangeal joints and the metacarpophalangeal joints. Distal expansion of the long bones as well as painf ...
(HPOA), known in continental Europe as Pierre Marie-Bamberger syndrome. This is the combination of clubbing and thickening of periosteum
The periosteum is a membrane that covers the outer surface of all bones, except at the articular surfaces (i.e. the parts within a joint space) of long bones. Endosteum lines the inner surface of the medullary cavity of all long bones.
Structure ...
(connective tissue lining of the bones) and synovium
The synovial membrane (also known as the synovial stratum, synovium or stratum synoviale) is a specialized connective tissue that lines the inner surface of capsules of synovial joints and tendon sheath. It makes direct contact with the fibrous ...
(lining of joints), and is often initially diagnosed as arthritis
Arthritis is a term often used to mean any disorder that affects joints. Symptoms generally include joint pain and stiffness. Other symptoms may include redness, warmth, swelling, and decreased range of motion of the affected joints. In som ...
. It is commonly associated with lung cancer.
Primary hypertrophic osteoarthropathy
Primary hypertrophic osteoarthropathy is HPOA without signs of pulmonary disease. This form has a hereditary component, although subtle cardiac abnormalities can occasionally be found. It is known eponymously as the Touraine–Solente–Golé syndrome. This condition has been linked to mutations in the gene on the fourth chromosome (4q33-q34) coding for the enzyme 15-hydroxyprostaglandin dehydrogenase (HPGD); this leads to decreased breakdown of prostaglandin E2
Prostaglandin E2 (PGE2), also known as dinoprostone, is a naturally occurring prostaglandin with oxytocic properties that is used as a medication. Dinoprostone is used in labor induction, bleeding after delivery, termination of pregnancy, and ...
and elevated levels of this substance.
Pathogenesis
The exact cause for sporadic clubbing is unknown. Theories as to its cause include:
* Vasodilation
Vasodilation is the widening of blood vessels. It results from relaxation of smooth muscle cells within the vessel walls, in particular in the large veins, large arteries, and smaller arterioles. The process is the opposite of vasoconstriction, ...
(i.e., distended blood vessels).
* Secretion of growth factor
A growth factor is a naturally occurring substance capable of stimulating cell proliferation, wound healing, and occasionally cellular differentiation. Usually it is a secreted protein or a steroid hormone. Growth factors are important for regu ...
s (e.g., platelet-derived growth factor
Platelet-derived growth factor (PDGF) is one among numerous growth factors that regulate cell growth and division. In particular, PDGF plays a significant role in blood vessel formation, the growth of blood vessels from already-existing blood v ...
and hepatocyte growth factor
Hepatocyte growth factor (HGF) or scatter factor (SF) is a paracrine cellular growth, motility and morphogenic factor. It is secreted by mesenchymal cells and targets and acts primarily upon epithelial cells and endothelial cells, but also acts o ...
) from the lungs.
* Overproduction of prostaglandin E2 by other tissues.[
* Increased entry of ]megakaryocyte
A megakaryocyte (''mega-'' + '' karyo-'' + '' -cyte'', "large-nucleus cell") is a large bone marrow cell with a lobated nucleus responsible for the production of blood thrombocytes (platelets), which are necessary for normal blood clotting. In hum ...
s into the systemic circulation. Under normal circumstances in healthy individuals, megakaryocytes that arise from the bone marrow are trapped in the pulmonary capillary bed and broken down before they enter the systemic circulation. It is thought that in disorders where there is right-to-left shunting or lung malignancy, the megakaryocytes can bypass the breakdown within the pulmonary circulation and enter the systemic circulation. They are then trapped within the capillary beds within the extremities, such as the digits, and release platelet-derived growth factor
Platelet-derived growth factor (PDGF) is one among numerous growth factors that regulate cell growth and division. In particular, PDGF plays a significant role in blood vessel formation, the growth of blood vessels from already-existing blood v ...
(PDGF) and vascular endothelial growth factor
Vascular endothelial growth factor (VEGF, ), originally known as vascular permeability factor (VPF), is a signal protein produced by many cells that stimulates the formation of blood vessels. To be specific, VEGF is a sub-family of growth factors, ...
(VEGF). PDGF and VEGF have growth promoting properties and cause connective tissue hypertrophy and capillary permeability.
Diagnosis
When clubbing is observed, pseudoclubbing should be excluded before making the diagnosis. Associated conditions may be identified by taking a detailed medical history
The medical history, case history, or anamnesis (from Greek: ἀνά, ''aná'', "open", and μνήσις, ''mnesis'', "memory") of a patient is information gained by a physician by asking specific questions, either to the patient or to other peo ...
—particular attention is paid to lung, heart, and gastrointestinal conditions—and conducting a thorough clinical examination
In a physical examination, medical examination, or clinical examination, a medical practitioner examines a patient for any possible medical signs or symptoms of a medical condition. It generally consists of a series of questions about the patient ...
, which may disclose associated features relevant to the underlying diagnosis. Additional studies such as a chest X-ray
A chest radiograph, called a chest X-ray (CXR), or chest film, is a projection radiograph of the chest used to diagnose conditions affecting the chest, its contents, and nearby structures. Chest radiographs are the most common film taken in med ...
and a chest CT-scan may reveal otherwise asymptomatic cardiopulmonary disease.[
]
Stages
Clubbing is present in one of five stages:
* No visible clubbing - Fluctuation (increased ballotability) and softening of the nail bed only. No visible changes of nails.
* Mild clubbing - Loss of the normal <165° angle (Lovibond angle) between the nailbed and the fold (cuticula). Schamroth's window (see below) is obliterated. Clubbing is not obvious at a glance.
* Moderate clubbing - Increased convexity of the nail fold. Clubbing is apparent at a glance.
* Gross clubbing - Thickening of the whole distal
Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position pro ...
(end part of the) finger (resembling a drumstick)
* Hypertrophic osteoarthropathy
Hypertrophic osteoarthropathy is a medical condition combining clubbing and periostitis of the small hand joints, especially the distal interphalangeal joints and the metacarpophalangeal joints. Distal expansion of the long bones as well as pai ...
- Shiny aspect and striation
Striations means a series of ridges, furrows or linear marks, and is used in several ways:
* Glacial striation
* Striation (fatigue), in material
* Striation (geology), a ''striation'' as a result of a geological fault
* Striation Valley, in Ant ...
of the nail and skin
Schamroth's sign or Schamroth's window test (originally demonstrated by South African cardiologist Leo Schamroth
Leo Schamroth (2 June 1924 in Belgium – 24 May 1988 in Johannesburg) was a South African cardiologist remembered for his work in electrocardiography and for describing Schamroth's window test.
Biography
Schamroth was born in Belgium a ...
on himself) is a popular test for clubbing. When the distal phalanges
The phalanges (singular: ''phalanx'' ) are digital bones in the hands and feet of most vertebrates. In primates, the thumbs and big toes have two phalanges while the other digits have three phalanges. The phalanges are classed as long bones.
...
(bones nearest the fingertips) of corresponding fingers of opposite hands are directly opposed (place fingernails of same finger on opposite hands against each other, nail to nail), a small diamond-shaped "window" is normally apparent between the nailbeds. If this window is obliterated, the test is positive and clubbing is present.
File:Clubbing of fingers.jpg, Severe clubbing
Clubbing2.JPG, Front view
Clubbing1.JPG, Side views
CongenitalHeartCase-133.jpg, Cyanotic nail beds
Epidemiology
The exact frequency of clubbing in the population is not known. A 2008 study found clubbing in 1%, or 15 patients, of 1511 patients admitted to a department of internal medicine in Belgium
Belgium, ; french: Belgique ; german: Belgien officially the Kingdom of Belgium, is a country in Northwestern Europe. The country is bordered by the Netherlands to the north, Germany to the east, Luxembourg to the southeast, France to th ...
. Of these, 40%, or 6 patients, turned out to have significant underlying disease of various causes, while 60%, or 9 patients, had no medical problems on further investigations and remained well over the subsequent year.[
]
History
At least since the time of Hippocrates
Hippocrates of Kos (; grc-gre, Ἱπποκράτης ὁ Κῷος, Hippokrátēs ho Kôios; ), also known as Hippocrates II, was a Greek physician of the classical period who is considered one of the most outstanding figures in the history of ...
, clubbing has been recognized as a sign of disease.[ The phenomenon has been called "Hippocratic fingers".
]
See also
* Clubbed thumb
Clubbed Thumb is a downtown theater company in New York City that commissions, develops, and produces "funny, strange, and provocative new plays by living American writers." Since its founding in 1996, the company has earned five OBIES (including t ...
(unrelated congenital deformity)
References
{{Respiratory system symptoms and signs
Conditions of the skin appendages
Symptoms and signs: musculoskeletal system