Clubbing
Encyclopedia
In medicine
, nail clubbing (also known as "Drumstick fingers," "Hippocratic fingers," and "Watch-glass nails") is a deformity of the finger
s and fingernail
s that is associated with a number of diseases, mostly of the heart
and lungs. Hippocrates
was probably the first to document clubbing as a sign of disease, and the phenomenon is therefore occasionally called Hippocratic fingers.
Idiopathic
clubbing can also occur, and in 60% of cases there is no associated underlying disease.
Schamroth's test or Schamroth's window test (originally demonstrated by South African cardiologist Dr Leo Schamroth
on himself) is a popular test for clubbing. When the distal phalanges (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.
—particular attention is paid to lung, heart, and gastrointestinal conditions—and conducting a clinical examination, which may disclose associated features relevant to a diagnosis. Additional studies such as a chest X-ray
and a chest CT-scan may also be performed.
Clubbing is associated with:
(connective tissue lining of the bones) and synovium
(lining of joints), and is often initially diagnosed as arthritis
. It is commonly associated with lung cancer.
(HPGD); this leads to decreased breakdown of prostaglandin E2 and elevated levels of this substance.
(distended blood vessels), secretion of growth factor
s (such as platelet-derived growth factor
and hepatocyte growth factor
) from the lungs, and other mechanisms have been proposed. The discovery of disorders in the prostaglandin
metabolism in primary osteo-arthropathy has led to suggestions that overproduction of PGE2 by other tissues may be the causative factor for clubbing.
. Of these, 40% turned out to have significant underlying disease of various causes, while 60% had no medical problems on further investigations and remained well over the subsequent year.
Medicine
Medicine is the science and art of healing. It encompasses a variety of health care practices evolved to maintain and restore health by the prevention and treatment of illness....
, nail clubbing (also known as "Drumstick fingers," "Hippocratic fingers," and "Watch-glass nails") is a deformity of the finger
Finger
A finger is a limb of the human body and a type of digit, an organ of manipulation and sensation found in the hands of humans and other primates....
s and fingernail
Nail (anatomy)
A nail is a horn-like envelope covering the dorsal aspect of the terminal phalanges of fingers and toes in humans, most non-human primates, and a few other mammals. Nails are similar to claws, which are found on numerous other animals....
s that is associated with a number of diseases, mostly of the heart
Heart disease
Heart disease, cardiac disease or cardiopathy is an umbrella term for a variety of diseases affecting the heart. , it is the leading cause of death in the United States, England, Canada and Wales, accounting for 25.4% of the total deaths in the United States.-Types:-Coronary heart disease:Coronary...
and lungs. Hippocrates
Hippocrates
Hippocrates of Cos or Hippokrates of Kos was an ancient Greek physician of the Age of Pericles , and is considered one of the most outstanding figures in the history of medicine...
was probably the first to document clubbing as a sign of disease, and the phenomenon is therefore occasionally called Hippocratic fingers.
Idiopathic
Idiopathic
Idiopathic is an adjective used primarily in medicine meaning arising spontaneously or from an obscure or unknown cause. From Greek ἴδιος, idios + πάθος, pathos , it means approximately "a disease of its own kind". It is technically a term from nosology, the classification of disease...
clubbing can also occur, and in 60% of cases there is no associated underlying disease.
Signs and symptoms
Clubbing develops in five steps:- Fluctuation and softening of the nail bed (increased ballotability)
- Loss of the normal <165° angle (Lovibond angle) between the nailbed and the fold (cuticula)
- Increased convexity of the nail fold
- Thickening of the whole distal (end part of the) finger (resembling a drumstick)
- Shiny aspect and striation of the nail and skin
Schamroth's test or Schamroth's window test (originally demonstrated by South African cardiologist Dr Leo Schamroth
Leo Schamroth
Leo Schamroth was a South African cardiologist remembered for his work in electrocardiography and for describing Schamroth's window test.- Biography :...
on himself) is a popular test for clubbing. When the distal phalanges (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.
Diagnosis
When clubbing is encountered in patients, doctors will seek to identify its cause. They usually accomplish this by obtaining a medical historyMedical history
The medical history or anamnesis of a patient is information gained by a physician by asking specific questions, either of the patient or of other people who know the person and can give suitable information , with the aim of obtaining information useful in formulating a diagnosis and providing...
—particular attention is paid to lung, heart, and gastrointestinal conditions—and conducting a clinical examination, which may disclose associated features relevant to a diagnosis. Additional studies such as a chest X-ray
Chest X-ray
In medicine, a chest radiograph, commonly called a chest X-ray , is a projection radiograph of the chest used to diagnose conditions affecting the chest, its contents, and nearby structures...
and a chest CT-scan may also be performed.
Disease associations
Although many diseases are associated with clubbing (particularly lung diseases), the reports are fairly anecdotal. Prospective studies of patients presenting with clubbing have not yet been performed, and hence there is no conclusive evidence of these associations.Isolated clubbing
- Lung disease:
- Lung cancerLung cancerLung cancer is a disease characterized by uncontrolled cell growth in tissues of the lung. If left untreated, this growth can spread beyond the lung in a process called metastasis into nearby tissue and, eventually, into other parts of the body. Most cancers that start in lung, known as primary...
, mainly non-small cell (54% of all cases), not seen frequently in small cell lung cancer (< 5% of cases) - Interstitial lung disease
- TuberculosisTuberculosisTuberculosis, MTB, or TB is a common, and in many cases lethal, infectious disease caused by various strains of mycobacteria, usually Mycobacterium tuberculosis. Tuberculosis usually attacks the lungs but can also affect other parts of the body...
- Suppurative lung disease: lung abscessLung abscessLung abscess is necrosis of the pulmonary tissue and formation of cavities containing necrotic debris or fluid caused by microbial infection....
, empyemaEmpyemaPleural empyema is an accumulation of pus in the pleural cavity. Most pleural empyemas arise from an infection within the lung , often associated with parapneumonic effusions. There are three stages: exudative, fibrinopurulent and organizing. In the exudative stage, the pus accumulates...
, bronchiectasisBronchiectasisBronchiectasis is a disease state defined by localized, irreversible dilation of part of the bronchial tree caused by destruction of the muscle and elastic tissue. It is classified as an obstructive lung disease, along with emphysema, bronchitis, asthma, and cystic fibrosis...
, cystic fibrosisCystic fibrosisCystic fibrosis is a recessive genetic disease affecting most critically the lungs, and also the pancreas, liver, and intestine... - Pleural Mesothelioma
- A·V fistula
- Lung cancer
- Heart disease:
- Any disease featuring chronic hypoxiaHypoxia (medical)Hypoxia, or hypoxiation, is a pathological condition in which the body as a whole or a region of the body is deprived of adequate oxygen supply. Variations in arterial oxygen concentrations can be part of the normal physiology, for example, during strenuous physical exercise...
- Congenital cyanotic heart disease (most common cardiac cause)
- Subacute bacterial endocarditisEndocarditisEndocarditis is an inflammation of the inner layer of the heart, the endocardium. It usually involves the heart valves . Other structures that may be involved include the interventricular septum, the chordae tendineae, the mural endocardium, or even on intracardiac devices...
- Atrial myxomaAtrial myxomaAn atrial myxoma is a benign tumor found in the heart, commonly in the upper left or right side. It grows on the wall that separates the two sides of the heart.-Causes:Myxomas are the most common type of primary heart tumor....
(benign tumor)
- Any disease featuring chronic hypoxia
- Gastrointestinal and hepatobiliary:
- MalabsorptionMalabsorptionMalabsorption is a state arising from abnormality in absorption of food nutrients across the gastrointestinal tract.Impairment can be of single or multiple nutrients depending on the abnormality...
- Crohn's diseaseCrohn's diseaseCrohn's disease, also known as regional enteritis, is a type of inflammatory bowel disease that may affect any part of the gastrointestinal tract from mouth to anus, causing a wide variety of symptoms...
and ulcerative colitisUlcerative colitisUlcerative colitis is a form of inflammatory bowel disease . Ulcerative colitis is a form of colitis, a disease of the colon , that includes characteristic ulcers, or open sores. The main symptom of active disease is usually constant diarrhea mixed with blood, of gradual onset... - CirrhosisCirrhosisCirrhosis is a consequence of chronic liver disease characterized by replacement of liver tissue by fibrosis, scar tissue and regenerative nodules , leading to loss of liver function...
, especially in primary biliary cirrhosisPrimary biliary cirrhosisPrimary biliary cirrhosis, often abbreviated PBC, is an autoimmune disease of the liver marked by the slow progressive destruction of the small bile ducts within the liver. When these ducts are damaged, bile builds up in the liver and over time damages the tissue. This can lead to scarring,... - Hepatopulmonary syndromeHepatopulmonary syndromeIn medicine, hepatopulmonary syndrome is a syndrome of shortness of breath and hypoxemia caused by vasodilation in the lungs of patients with liver disease...
, a complication of cirrhosis - Laxative abuse
- Polyposis
- Esophageal CA
- Malabsorption
- Others:
- HyperthyroidismHyperthyroidismHyperthyroidism is the term for overactive tissue within the thyroid gland causing an overproduction of thyroid hormones . Hyperthyroidism is thus a cause of thyrotoxicosis, the clinical condition of increased thyroid hormones in the blood. Hyperthyroidism and thyrotoxicosis are not synonymous...
(thyroid acropachyAcropachyAcropachy is a medical condition characterized by subperiosteal new bone formation, . This most commonly manifests as clubbing of the fingers and toes with soft tissue swelling. It is sometimes associated with Graves' disease but not with other causes of hyperthyroidism...
) - Familial and racial 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 (in unilateral clubbing)
- ThymomaThymomaThymoma is a tumor originating from the epithelial cells of the thymus. Thymoma is an uncommon tumor, best known for its association with the neuromuscular disorder myasthenia gravis. Thymoma is found in 15% of patients with myasthenia gravis. Once diagnosed, thymomas may be removed surgically...
- ThalassemiaThalassemiaThalassemia is an inherited autosomal recessive blood disease that originated in the Mediterranean region. In thalassemia the genetic defect, which could be either mutation or deletion, results in reduced rate of synthesis or no synthesis of one of the globin chains that make up hemoglobin...
- Hyperthyroidism
HPOA
A special form of clubbing is hypertrophic pulmonary osteo-arthropathy, known in continental Europe as Pierre Marie-Bamberger syndrome. This is the combination of clubbing and thickening of periosteumPeriosteum
Periosteum is a membrane that lines the outer surface of all bones, except at the joints of long bones. Endosteum lines the inner surface of all bones....
(connective tissue lining of the bones) and synovium
Synovium
Synovial membrane is the soft tissue found between the articular capsule and the joint cavity of synovial joints....
(lining of joints), and is often initially diagnosed as arthritis
Arthritis
Arthritis is a form of joint disorder that involves inflammation of one or more joints....
. It is commonly associated with lung cancer.
Primary HOA
Primary hypertrophic osteo-arthropathy 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 dehydrogenase15-hydroxyprostaglandin dehydrogenase (NAD+)
In enzymology, a 15-hydroxyprostaglandin dehydrogenase is an enzyme that catalyzes the chemical reaction--11alpha,15-dihydroxy-9-oxoprost-13-enoate + NAD+ \rightleftharpoons -11alpha-hydroxy-9,15-dioxoprost-13-enoate + NADH + H+...
(HPGD); this leads to decreased breakdown of prostaglandin E2 and elevated levels of this substance.
Pathophysiology
The exact cause for sporadic clubbing is unknown, and there are numerous theories as to its cause. VasodilationVasodilation
Vasodilation refers to the widening of blood vessels resulting from relaxation of smooth muscle cells within the vessel walls, particularly in the large arteries, smaller arterioles and large veins. The process is essentially the opposite of vasoconstriction, or the narrowing of blood vessels. When...
(distended blood vessels), secretion of growth factor
Growth factor
A growth factor is a naturally occurring substance capable of stimulating cellular growth, proliferation and cellular differentiation. Usually it is a protein or a steroid hormone. Growth factors are important for regulating a variety of cellular processes....
s (such as platelet-derived growth factor
Platelet-derived growth factor
In molecular biology, platelet-derived growth factor is one of the numerous growth factors, or proteins that regulate cell growth and division. In particular, it plays a significant role in blood vessel formation , the growth of blood vessels from already-existing blood vessel tissue. Uncontrolled...
and hepatocyte growth factor
Hepatocyte growth factor
Hepatocyte growth factor/scatter factor 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 on haemopoietic progenitor cells...
) from the lungs, and other mechanisms have been proposed. The discovery of disorders in the prostaglandin
Prostaglandin
A prostaglandin is any member of a group of lipid compounds that are derived enzymatically from fatty acids and have important functions in the animal body. Every prostaglandin contains 20 carbon atoms, including a 5-carbon ring....
metabolism in primary osteo-arthropathy has led to suggestions that overproduction of PGE2 by other tissues may be the causative factor for clubbing.
Epidemiology
The exact frequency of clubbing in the population is not known. A 2008 study found clubbing in 1% of all patients admitted to a department of internal medicineInternal medicine
Internal medicine is the medical specialty dealing with the prevention, diagnosis, and treatment of adult diseases. Physicians specializing in internal medicine are called internists. They are especially skilled in the management of patients who have undifferentiated or multi-system disease processes...
. Of these, 40% turned out to have significant underlying disease of various causes, while 60% had no medical problems on further investigations and remained well over the subsequent year.
See also
- Periosteal reactionPeriosteal reactionA periosteal reaction is the formation of new bone in response to injury or other stimuli of the periosteum surrounding the bone. It is most often identified on X-ray films of the bones.-Etiology:...
- Clubbed thumbClubbed thumbA clubbed thumb is a term used to describe the genetic clubbing of one or both thumbs. It is characterized by a short, fat thumb that is round. The thumb nail is wide and short...
(unrelated congenital deformity) - List of cutaneous conditions