Ver el código de «Eponyms (T-Z)»

==T==

===[[Takayasu arteritis|Takayasu's disease]]===
Aortic arch syndrome, pulseless disease; panartertis of the great vessels that is most common in Asian women. Described in 1908 by Takayasu, an ophthalmologist. 

===[[Takotsubo cardiomyopathy]]===
Apical ballooning syndrome, characterized by acute onset of chest pain, ECG changes, cardiac marker release and transient extensive akinesia of the apical portions of left ventricle without significant coronary stenosis. 

===Tamm-Horsfall protein===
Uromodulin, major component of renal casts; 30-50mg secreted per day by cells in thick ascending limb; homologous to GP2, a protein secreted from the acinar cell and a major component of plugs in noncalcific chronic pancreatitis. 

===Tangier disease===
Rare recessive disease characterized by enlarged orange tonsils, peripheral neuropathy affecting small fibers involved in pain and temperature, and a near-complete absence of HDL-cholesterol. ABC1, the ATP binding-cassette transporter 1 gene, mutated in Tangier disease; gene mediates efflux of cholesterol from cells. Named after small island in Chesapeake Bay where disease first identified in five-year-old boy. 

===Tanner stages===
Stages of sexual development in puberty; described by James Tanner. 

===Tarlov cyst===
Perineural cyst found in the lower spinal cord. 

===Tarui disease===
Glycogen storage disease type VII, deficiency of muscle phophofructokinase, presents as early onset of fatigue and pain with exercise, resulting in myoglobinuria. 

===Tay syndrome===
Icthyosiform erythroderma with hair abnormality and mental and growth retardation. Also known as IBIDS syndrome (i.e. ichthyosis + BIDS syndrome (hair-brain syndrome), with BIDS standing for brittle hair, intellectual impairment, decreased fertility, and short stature). Tay in Tay syndrome different Tay from Tay in Tay-Sachs. 

===Tay-Sachs disease===
Autosomal recessive sphingolipidosis; GM2 gangliosidosis, results from mutations that affect alpha subunit of hexosaminidase A gene and cause a severe deficiency in hexosaminidase A; blindness and cherry-red spot (see also Sandhoff's disease with similar symptoms; involves beta subunit of both hexosaminidase A and B); previously called "amaurotic idiocy." Fatal in early childhood. 

===Terry's nails===
Mostly whitish nails with a distal band of reddish brown; may be seen with aging and in people with chronic diseases such as cirrhosis of the liver, congestive heart failure, renal disease, and diabetes; seen in 10% of patients with uremia. 

===Terson's syndrome===
Intra-vitreous hemorrhage associated with subarachnoid hemorrhage. 

===Texidor's twinge===
Sudden and sharp chest pain in pediatric settings, from precordial catch or sudden restrictrion in pleural movement. Described by Miller and Texidor in 1955. 

===Third disease===
German measles, aka [[rubella]] or rötheln, caused by rubivirus, described in 1881. 

===Thomas test===
To test for hip flexion deformity due to e.g. osteoarthritis, while lying supine, patient flexes unaffected leg at the hip. If patient is unable to keep contralateral leg flat, then test is positive. Other variants of test exist. 

===Thompson's test===
Verifies if gastroc-soleus complex intact: squeeze calf belly, foot should plantar flex. Lack of plantarflexion indicates [[Achilles tendon rupture]]. See also Simmond's test. 

===Thomsen-Friedenreich antigen===
Cryptic antigen in membranes of erythrocytes, platelets, and glomerular capillary endothelial cells exposed by S. pneumoniae-derived neuraminidase removal of sialic acid. 

===Thomsen's disease===
Myotonia congenita. Autosomal dominant. From mutation in skeletal muscle chloride channel 1 (CLCN1). Characterized by muscle stiffness and inability to relax after muscle contraction. 

===Thorel's pathway===
Posterior internodal tract in atrial conduction system. 

===Throckmorton sign===
Positive sign when penis points towards lesion seen radiographically; see also John Thomas sign. 

===Tietze syndrome===
Benign inflammation and swelling of costochondral and costosternal joints which are painful on palpation; may be perceived as breast pain. 

===[[Tillaux fracture]]===
Fracture seen in older adolescents in which the anterolateral portion of the distal tibial epiphyseal plate is avulsed from the medial portion of the plate by the anterior tibiofibular ligament. 

===Tinel's sign===
A sensation of tingling or pins and needles felt in distal extremity when percussion is made over the site of an injured nerve, as in [[carpal tunnel syndrome]]; it indicates a partial lesion or early regeneration of the nerve; 60% sensitive, 67% specific. 

===Todd's paralysis===
Transient hemiparesis in postictal period, resolves over a period of 0.5-36 hours, suggests focal brain lesion as cause. 

===Toldt, white lines of===
The peritoneal reflections of the ascending and descending colon. 

===Tolosa-Hunt syndrome===
Idiopathic inflammation of the cavernous sinus producing painful palsy of third, fourth, or sixth cranial nerve. 

===Tornwaldt's bursa===
Pharyngeal bursa, located above the pharyngeal tonsil in the midline of the posterior wall of the nasopharynx; remnant of embryonic communication between the anterior tip of the notochord and the roof of the pharynx. 

===Tourette's syndrome===
Chronic multiple motor and verbal tics, symptoms typically begin before 21 y.o., first signs motor tics in 80% and vocal tics in 20% but eventually both motor and vocal; higher than expected number of left-handedness and ambidexterity; 40-50% involve self-mutilation such as nail-biting, hair-pulling, etc. 

===Towne's view===
AP view with the X ray tube angled caudad to show the occipital bone. 

===Traube's sign===
In aortic regurgitation "pistol shot sounds" referring to booming systolic and diastolic sounds over the femoral artery. 

===Traube's space===
A crescentic space about 12 cm wide, bounded medially by the left sternal border, above by an oblique line from 6th costal cartilage to the lower border of the 8th or 9th rib in the mid-axillary line, and below by costal margin. Usually tympanitic because of stomach but can be affected by emphysema, pleural effusion, or splenomegaly. 

===Treacher Collins syndrome===
First arch syndrome, mandibulofacial dysplasia, resulting in malar hypoplasia with down-slanting palpebral fissures, defects in the lower eyelids, deformed external ears, and sometimes abnormalities of the middle and internal ears. Autosomal dominant, due to mutation in trecle gene, TCOF1. Described by Edward Treacher Collins, an English surgeon and ophthalmologist (1862-1932). 

===Treitz, ligament of===
Suspensory muscle of the duodenum which supports the duodenojejunal flexure. Separates upper from lower gastrointestinal bleeding. 

===Trendelenburg position===
Position where angle of the head of bed or table is inclined at 45 degrees down; used in surgery to push the abdominal organs towards the chest. 

===Trendelenburg's gait===
Waddling gait in people with weakness or paresis of gluteal muscles; seen in progressive muscular dystrophy. 

===Trendelenburg's sign===
Sign of weakness of gluteus medius muscle seen when standing on one leg, failure to elevate contralateral side of pelvis. May be due to congenital dislocation of hip, trochanteric fracture, polio, or spinal nerve root lesions with muscule atrophy. 

===Trevor's disease===
Also known as dysplasia epiphysealis hemimelica, asymmetric limb deformity due to cartilaginous overgrowth of a tarsal or carpal bone, less often other bones. 

===Troisier's node===
French eponym for Virchow's node. 

===Trotter's syndrome===
Triad of unilateral deafness due to eustachian tube involvement, neuralgia affecting branches of the trigeminal nerve, and defective mobility of the soft palate due to nasopharyngeal cancer. 

===Trousseau's sign===
In [[hypocalcemia]] and latent tetany, carpal spasm induced by occluding the brachial artery for 3 min with an inflated BP cuff. 

===Trousseau's spot===
Also known as tache cerebrale, the red streak seen on scratching the skin in acute meningitis. 

===Trousseau's syndrome===
Migratory [[thrombophlebitis]] seen in setting of malignancy, e.g. pancreas or lung. 

===Trummerfeld zone===
In scurvy, a lucent line below a dense zone of provisional calification at the margins of the growth plate (i.e. Fränkel's sign). 

===Tullio's phenomenon===
Induction of vertigo by loud noises, i.e. sound-induced vestibular activation. Associated with and previously considered pathognomonic of syphilis. 

===Turcot's syndrome===
Rare variant of familial adenomatous polyposis, with combination of adenomatous colonic polyposis and tumors of the central nervous system, mostly glioblastoma multiforme. 

===Turner's syndrome===
Females with XO, short, low-set ears, shield chest, congenital heart defect (usually coarctation), café-au-lait spots, freckles, webbed neck, lymphedema. 

===Tzanck smear===
Cytologic technique most often used in the diagnosis of herpesvirus infections (simplex or varicella-zoster); multinucleated giant cells suggest the presence of herpes; named after Arnault Tzanck. 

==U==
===Uhl's anomaly===
Paper-thin parietal myocardium, usually but not always limited to right ventricle, presents as heart failure in infancy or early childhood. 

===Uhthoff's phenomenon===
In [[multiple sclerosis]], sensitivity of symptoms to changes in body temperature or exercise (e.g., visual loss with exercise); initial description in 1890 of amblyopia following exercise. 

===Unhappy triad===
Lateral knee injury resulting in anterior cruciate ligament (ACL) tear, medial collateral ligament (MCL) tear, and medial meniscal injury. 

===Unna boot===
Compression dressing impregnated with medication for treating venous stasis ulcers; named after Paul Gerson Unna, German dermatologist 1850-1929. 

===Unterberger's stepping test===
For assessing vestibular function, having patient step in one spot with the eye closed: in peripheral lesions, body rotates to side of lesion whereas in central disorders, deviation is irregular. 

===Unverricht-Lundborg disease===
Progressive myoclonus epilepsy (EPM1), onset at age 6-15, stimulus-sensitive myoclonus, tonic-clonic seizures, marked sensitivity to photic stimulation, leads to cerebellar ataxia and mental deterioration; from unstable expansion of a dodecamer minisatellite repeat unit in the promoter region of cystatin B, a widely expressed cysteine protease inhibitor; more common in Finland and western Mediterranean; also known as Baltic myoclonus. 

===Upshaw-Schulman syndrome===
Congenital thrombotic thrombocytopenic purpura (TTP); caused by an inherited deficiency in von Willebrand factor cleaving metalloprotease (ADAMTS13), characterized by the constellation of findings seen in TTP, namely microangiopathic hemolytic anemia, thrombocytopenia, neurologic symptoms, renal dysfunction, and fever. 

===Urbach-Wiethe disease===
Lipoid proteinosis with cutaneous and mucosal infiltrations of eyelids, tongue, larynx; associated with early hoarseness with an unusual skin eruption. Autosomal recessive, associated with mutation in ECM1 gene. 

===Usher's syndrome===
Type I, profound bilateral sensorineural congenital deafness with onset of loss of vision due to retinitis pigmentosa by age 10 (type 1B due to mutation in myosin-VIIa); type 2, moderate to severe congenital deafness with onset of retinitis pigmentosa by age 10; type III, retinitis pigmentosa first noted at puberty with progressive hearing loss; type IV, possible X-linked form. 

===Utley's maneuver===
For controlling bleeding from a tracheo-innominate fistula, digital pressure through the stoma on the back of the sternum to controls the fistula. 

==V==
===Valentino's syndrome===
[[Duodenal ulcer]] with retroperitoneal perforation presenting with pain in the right lower quadrant. 

===Valsalva maneuver===
First described in 1704 as a method for expelling pus from the middle ear: deep inspiration followed by forced exhalation against a closed glottis for 10-12 seconds; four phases, phase 1 transient rise in BP with straining; phase 2 decrease in systemic venous return, blood pressure, and reflex tachycardia; phase 3 begins with cessation of straining, associated with abrupt transient decrease in blood pressure and in systemic venous return (generally not perceivable); phase 4 an overshoot of systemic arterial pressure and relatively obvious reflex bradcycardia. Described by Valsalva, a 17th century physician. 

===Van den Bergh reaction===
Used to distinguish between unconjugated and conjugated bilirubin; bilirubin pigments are exposed to sulfanilic acid to generate diazo conjugates, forming chromogenic products. 

===Van der Hoeve syndrome===
Osteogenesis imperfecta. 

===Van der Woude syndrome===
An autosomal dominant condition in which lip pits are seen in all gene carriers but only some individuals have cleft lips with or without cleft palate owing to variable expressivity. 

===Van Wyk-Grumbach syndrome===
Primary hypothyroidism associated with precocious puberty and galactorrhea. 

===Vanek tumor===
Benign inflammatory fibroid polyp seen in gastrointestinal tract. 

===Van't Hoff's law===
Osmotic pressure of a solute equals the gas pressure it would exert if it were a gas in the same volume of solution. Dutch chemist (1852-1911), received Nobel Prize for this finding in 1901. 

===Vater, ampulla===
Location where common bile duct enters the duodenum; described by German anatomist Vater (1684-1751). 

===Vaughn-Jackson lesion===
Seen in rheumatoid arthritis, rupture of tendons in distal ulnar head, associated with loss of extension in the little and ring, finger; associated with caput ulna syndrome. 

===Verner-Morrison syndrome===
Secretory diarrhea associated with VIPoma; characterized by watery diarrhea, hypokalemia, achlorhydria. 

===Vespignani sign===
Edema of the ureteral vesical junction in renal colic. 

===Vietnamese time bomb===
Burkholderia pseudomallei, causative agent of melioidosis, described as "time bomb" because of its occurrence in war veterans more than two decades after their return from Vietnam. 

===Villaret's syndrome===
Involvement of four lower cranial nerves (IX-XII) clinical manifestations manifesting as Horner's syndrome and paralysis of the soft palate, pharynx, and vocal cords; associated with tumor in posterior retroparotid space. 

===[[Vincent's angina]]===
Acute necrotizing ulcerative gingivitis or "trench mouth" from concurrent infection with the symbiotic bacteria Fusobacterium fusiforme and Borrelia vincentii. Rare in post-antibiotic era. 

===Virchow-Robin spaces===
Perivascular spaces in brain; become unusually widened in edema of the brain. 

===Virchow's node===
Supraclavicular adenopathy associated with a malignancy, often on left side, associated with GI (e.g. stomach) and pelvic malignancies. First described by Virchow in 1848, more cases added by Troisier in 1886; referred to as Troisier's node in France. 

===Virchow's triad===
Predisposing factors in thrombus formation (1) endothelial injury, (2) hypercoagulability, and (3) stasis or turbulence of blood flow; first described in 1860. 

===Vogt-Koyanagi-Harada syndrome===
Bilateral, diffuse granulomatous uveitis associated with poliosis (premature graying of some or all of the hair), vitiligo, alopecia, and central nervous system and auditory signs (including dysacusia). 

===Vogt's triad===
In tuberous sclerosis, triad of seizures, mental retardation, and facial angiofibromas. Occurs in fewer than 50% of patients with tuberous sclerosis. 

===Voight, lines of===
Boundaries which delimit distribution area of main cutaneous nerves; seen in black and Asian skin and rarely in white subjects. 

===Volkmann contracture===
Sequelae of compartment syndrome where there is contraction of forearm flexors. 

===von Braun-Fernwald's sign===
See Piskacek's sign. 

===Von Economo's encephalitis===
Encephalitis lethargica, associated with postencephalitic parkinsonism, first described in 1917; also associated with influenza A epidemic of 1918. Response to levodopa subject of book and movie Awakenings. 

===von Frey hairs===
Hairs originally derived from horses tails and graded according to their stiffness and caliber, used as a method of grading sensation in the neurologic examination. 

===Von Gierke's disease===
Glycogen storage disease type I, deficiency in glucose-6-phosphatase, results in hepatomegaly and hypoglycemia. Most common glycogen storage disease. Autosomal recessive. Treated with frequent feedings of foods high in glucose or starch. 

===Von Graefe sign===
In Graves's disease, lag of the upper eyelid as it follows the rotation of the eyeball downward. 

===Von Hippel-Lindau disease===
Autosomal dominant condition characterized by hemangioblastoma or cavernous hemangioma of the cerebellum, brain stem, or retina, adenomas, and cysts of the liver, kidney, pancreas, and other organs, pheochromocytomas; 35% develop renal cell carcinoma; associated with mutation in VHL gene. 

===Von Myenburg complexes===
Close to or within portal tracts, small clusters of modestly dilated bile ducts embedded in a fibrous, sometimes hyalinized stroma; contain inspissated bile concrements and may communicate with the biliary tree; common and usually without clinical significance. 

===Von Recklinghausen's disease===
Neurofibromatosis type 1. 

===Von Recklinghausen's disease of bone===
Generalized osteitis fibrosa cystica; hallmark of severe hyperparathyroidism, including increased bone cell activity, peritrabecular fibrosis, and cystic brown tumors. 

===Von Willebrand factor===
Von Willebrand factor bridges collagen and platelets and favors platelet aggregation, ensuring platelet and vessel wall interactions. Glycoprotein Ib-IX on platelets is a major receptor for vWF. vWF also serves as carrier for factor VIII. Made in endothelial cells and megakaryocytes. 

===[[Von Willebrand disease]]===
Deficiency in von Willebrand factor; frequency of 1%, most common inherited disorder of bleeding; type 1 and 3 reduced quantity of vWF; type 2 qualitative defects in vWF. 

===Von Zumbusch psoriasis===
Generalized acute pustular psoriasis.

==W==
===Waardenburg's syndrome===
TYPE I, hearing loss; dystopia canthorum, high nasal root, heterochromia irides, white forelock, early graying; from mutation in PAX3 gene, transcription factor involved in neural crest development; TYPE II, same as type I except for absence of dystopia; associated with mutation in MITF; TYPE III (Klein-Waardenburg), camptodactyly and other upper limb defects in addition to type I; TYPE IV (Shah-Waardenburg), deafness, pigmentary defects, and aganglionic megacolon. 

===Wada test===
A test for hemispheric dominance for language by injecting amobarbital into carotid artery, one hemisphere at a time; the barbiturate shuts down that hemisphere. Initially described by Wada in 1949. 

===Waddell's signs===
In low back pain, responses that predict worse outcome or non-organic component to pain, including tenderness unrelated to anatomic structures, inconsistent performance of seated versus supine straight leg raise, pain on axial loading, and neurological deficits without physiologic explanation. 

===Waddell's triad===
Triad of injury seen in children struck by motor vehicles: fractured femoral shaft; thoracic or abdominal injuries; contralateral head injury. 

===WAGR===
Wilms's tumor, Anirida, Genital anomalies, and mental Retardation; 33% chance of developing Wilms's tumor; associated with mutation in WT1 gene. 

===Waldenström's macroglobulinemia===
A subset of lymphoplasmacytic lymphoma (a malignancy involving small B lymphocytes, plasmactyoid lymphocytes, and plasma cells) with bone marrow involvement and IgM monoclonal gammopathy in the blood. Characterized by macroglobulinemia and associated with visual impairment, neurologic problems, bleeding, cryoglobulinemia, and hyperviscosity. 

===Waldeyer's throat ring===
The broken ring of lymphoid tissue, formed of the lingual, facial, and pharyngeal tonsils, commonly involved in non-Hodgkin's lymphoma and rarely in Hodgkin's disease. 

===Walker-Warburg syndrome===
Congenital condition characterized by hydrocephalus, agyria, retinal dysplasia, with or without encephalocele; autosomal recessive from mutation in O-mannosyltransferase-1 POMT1 and -2 POMT2; usually lethal within first few months. 

===Wallenberg syndrome===
Lateral medullary syndrome from infarction in posterior inferior cerebellar artery (PICA) which supplies the lateral medulla. This affects: (1) nucleus ambiguus, leading to difficulty in swallowing and hoarseness, loss of gag reflex; (2) vestibular nucleus, leading to dizziness and nystagmus; (3) trigeminal nucleus, leading to loss of pain and temperature on ipsilateral side; (4) inferior cerebellar peduncle, leading to ipsilateral limb ataxia; (5) anterolateral system, leading to reduced pain and temperature on contralateral limb; (6) ipsilateral Horner's syndrome; and (7) hiccup. For reasons not known solitary nucleus may also be destroyed, leading to loss of taste on ipsilateral half of tongue. 

===Wallerian degeneration===
Pattern of degeneration of distal portion of nerve following axonal injury with break down of axon and formation of myelin ovoids from catabolized axon fragments. 

===Warburg effect===
In malignant transformation, increased anaerobic glycolysis leads to increased lactic acid production; described by Otto Warburg in 1930. 

===Warren shunt===
For treating portal hypertension, distal splenorenal shunt. 

===Wartenberg migratory sensory neuritis===
Benign relapsing and remitting condition with pain and loss of sensation in distribution of individual cutaneous nerves; induced by stretch; intact deep-tendon reflexes. 

===Warthin-Finkeldey cells===
On measles pneumonia, cells with multiple nuclei and eosinophilic intranuclear inclusions. 

===Warthin's tumor===
Papillary cystadenoma lymphomatosum, parotid gland involved, benign, more in males than females, 50s-70s. 

===Warthin-Starry stain===
A silver stain, will stain H. pylori, Bartonella henselae. 

===Watanabe-Vigevano syndrome===
Benign familial and non-familial infantile seizures. Excellent prognosis with seizure remission. 

===Waterhouse-Friderichsen syndrome===
Massive bilateral adrenal hemorrhage seen with with N. meningitidis or gonococci, pneumococci, or Staph. septicemia, characterized by hypotension, DIC with widespread purpura, and adrenocortical insufficiency. 

===Waterston-Cooley shunt===
For treating tetralogy of Fallot, anastomosis of direct ascending aorta to right pulmonary artery; rarely performed currently. 

===Watson's water hammer pulse===
Also known as Corrigan's pulse; seen in aortic regurgitation. 

===Watson-Schwartz reaction===
Screening test for porphobilinogen (elevated for example in [[acute intermittent porphyria]]); mixing 4-dimethylaminobenzaldehyde with urine and then extract with chloroform; porphobilinogen extracts into upper aqueous layer giving it a pink color and urobilinogen extracts into chloroform layer; 50% positive at urinary concentration 5x upper limit of normal and consistently positive 10-20x upper limit of normal; see also Hoesch test.

===Weaver syndrome===
Congenital disorder associated with rapid growth beginning in the prenatal period, unusual craniofacial appearance, hoarse and low-pitched cry, and hypertonia with camptodactyly. Occasionally has mutations in NSD1 (which is same mutation in Sotos syndrome). 

===Weber fracture===
Used to determine the severity of tibiofibular ligament injury by the level of fibular fracture; Weber A, fibular fractures distal to the level of the tibiotalar joint; Weber B, fracture of the fibula near the joint and a transverse fracture of the medial malleolus (or disruption of the deltoid ligament); Weber C consists of a proximal fracture of the fibula and a transverse fracture of the medial malleolus (or an intact malleolus and a ruptured deltoid ligament). 

===Weber syndrome===
Medial midbrain syndrome with ipsilateral third nerve palsy combined with contralateral hemiplegia due to peduncular lesion. 

===Weber test===
512 Hz tuning fork placed on patients's forehead; sound localizes towards side with conductive hearing loss; localizes away from the side with sensorineural loss. 

===Weber-Christian disease===
Relapsing febrile nodular nonsuppurative nonvasculitic panniculitis (an inflammatory reaction in the subcutaneous fat). Usually occurs in young white females; characterized by tender skin nodules and constitutional symptoms (fever, arthralgias, myalgias). 

===[[Wegener's granulomatosis]]===
Systemic vasculitis of medium and small arteries, as well as venules and arterioles defined by a clinical triad of involvement of the upper airways, lungs, and kidneys and by a pathological triad consisting of necrotizing granuloma in the upper respiratory tract and lungs, vasculitis involving both arteries and veins, and focal glomerulonephritis. Described by Wegener in 1936, who was associated with Nazi party. 

===Weibel-Palade bodies===
Granules contain von Willebrand's factor and P-selectin, found in endothelial cells of vessels larger than capillaries. 

===Weigert stain===
Iron hematoxylin, preceded by a dichromate mordant, stains myelin. 

===Weil-Felix reaction===
Proteus cell wall O antigens, such as OX-2, OX-19, and OX-K, cross-reacting with antigens of several species of rickettsiae. 

===Weill-Marchesani syndrome===
Rare, autosomal recessive syndrome of ectopia lentis, short stature, brachydactyly, and glaucoma. Associated with mutation in ADAMTS10 gene. 

===Weil's disease===
Severe form of [[leptospirosis]] with hepatic dysfunction, renal dysfunction, and hemorrhage. 

===Welander distal myopathy===
Distal myopathy seen in Sweden and Finland. 

===[[Wellen's]] sign===
In critical stenosis high in left anterior descending coronary artery, a pattern of ST-T segment in V2 and V3: isoelectric or minimally elevated (1 mm) takeoff of the ST segment, a concave or straight ST segment passing into a negative T wave at an angle of 60 to 90 degrees, and a symmetrically inverted T wave (Am Heart J 103:730, 1982). 

===[[Wells Criteria]]===
Stratifies risk of DVT or PE

===Wells's syndrome===
Eosinophilic cellulitis, characterized by recurrent cutaneous swellings which resemble acute bacterial cellulitis, and by distinctive histopathological changes. Skin lesions show dermal eosinophilic infiltration and the characteristic "flame figures" are composed of eosinophil major protein deposited on collagen bundles. Described by Wells in 1971. 

===Wenckebach block===
Second-degree [[AV block]], Mobitz type I. 

===Wenckebach's bundle===
Middle internodal tract in atrial conduction system. 

===Werdnig-Hoffmann syndrome===
Spinal muscular atrophy type I, autosomal recessive lower motor neuron disease, survival motor neuron protein affected, due to mutation in SMN1, presents between birth and 6 months of age, death before 2 y.o. Characterized by degeneration of spinal cord anterior horn cells, resulting in muscle atrophy and weakness. Of note, spinal muscular atrophysecond most common lethal, autosomal recessive disease in Caucasians after cystic fibrosis. 

===Werlhof's disease===
[[Immune thrombocytopenic purpura]]; described by Werlhof in 1735. 

===Wermer's syndrome===
Multiple endocrine neoplasia (MEN) type I: hyperplasias or tumors of the thyroid, parathyroid, adrenal cortex, pancreatic islets, or pituitary. 

===Werner's syndrome===
A form of progeria characterized by scleroderma-like skin changes (especially in extremities), bilateral juvenile cataracts, subcutaneous calcifications, wizened and prematurely-aged facies, hypogonadism, and diabetes mellitus; autosomal recessive inheritance; from mutation in WRN helicase locus. 

===Wernicke's area===
Important cortical center for recognizing speech, found in the superior temporal gyrus; communicates with Broca's area with arcuate fasciulus. 

===[[Wernicke's encephalopathy]]===
Chronic thiamine deficiency (seen in alcoholics since alcohol impairs thiamine absorption) resulting in ataxia, global confusion, ophthalmoplegia, and often nystagmus. May lead to a particular focal necrotizing encephalopathy affecting the hypothalamus, medial thalamus, and oculomotor nuclear groups in the periventricular brainstem. Can be precipitated by administration of glucose to patient depleted of thiamine. After treatment with thiamine, a minority of patients have profound memory deficit (Korsakoff's syndrome). 

===Westermark's sign===
In chest film, an abrupt tapering of a vessel caused by [[pulmonary embolism]], focal oligemia. 

===West's syndrome===
Triad of infantile spasms, psychomotor developmental arrest, and characteristic EEG pattern of hypsarrhythmia (multifocal, chaotic, high-amplitude spike-and-slow wave pattern). 

===Wharton's duct===
Submandibular duct. 

===Wharton's jelly===
Gelatinous substance within the umbilical cord. 

===Whipple procedure===
Pancreaticoduodenectomy with cholecystectomy, truncal vagotomy, choledochojejunostomy, pancreaticojejunostomy, gastrojejunostomy. 

===Whipple's disease===
Systemic bacterial infection with Tropheryma whipplei characterized by fever (50%), weight loss (most common presenting symptom), diarrhea, lymphadenopathy, and polyarthritis (in 80%, first symptoms experienced) and, occasionally, by cardiac manifestations such as myocarditis, pericarditis, and endocarditis or by central nervous system involvement (10%); most commonly affects men in 40-60s. See small intestinal mucosa laden with distended macrophages in the lamina propria, PAS positive granules, with no inflammation; gram positive actinomycete Tropheryma whipplei. 

===Whipple's triad===
In insulinoma, (1) attacks precipitated by fasting or exertion; (2) fasting blood glucose <50mg/dL; (3) symptoms relieved by glucose. 

===Whitaker's syndrome===
Autoimmune polyglandular syndrome type 1 (mucocutaneous candidiasis, hypoparathyroidism, autoimmune adrenal insufficiency). 

===Wickham's striae===
In lichen planus, papules are highlighted by a shiny surface with a lacy white pattern. 

===Widal test===
Typhoid agglutination test. 

===Wilkie's disease===
Partial obstruction of third part of duodenum by superior mesenteric artery resulting in abdominal pain, nausea, vomiting, weight loss. 

===Will Rogers phenomenon===
Stage migration with improvements in diagnosis, causing apparent improvements in survival, i.e., stage I cases becoming stage II (N Engl J Med 1985;312:1604). 

===Williams-Campbell syndrome===
Congenital cartilage deficiency, associated with bronchiectasis. 

===Williams-Fitzgerald-Flaujeac factor===
High molecular weight kininogen; see description under Fitzgerald factor. 

===Williams's syndrome===
Neurodevelopmental disorder characterized by loquacious personality, abnormally sensitive hearing, supravalvular aortic stenosis, mental retardation, elfin facies, association with hypercalcemia due to abnormal sensitivity to vitamin D, idiopathic hypercalcemia of pregnancy. Due to deletion in elastin gene and probably several adjacent genes on 7q. 

===Willis, circle of===
Cerebral arterial circle, an anastomosis between the two vertebral and two internal carotid arteries. 

===[[Wilms' tumor]]===
Childhood primary renal tumor, 5% of patients with sporadic Wilms tumor have mutations in WT-1, cancer suppressor gene on 11p13.

===Wilson's disease===
Hepatolenticular degeneration, autosomal recessive disorder involving gene in incorporation of copper into ceruloplasmin and excretion of copper into bile, leading to accumulation of copper in liver and brain. Incidence 1:200,000, diagnosis based on decrease in serum ceruloplasmin, increased urinary excretion of copper, increase in hepatic copper content; 40% have neurologic findings (Parkinson's, psychosis) and subclinical liver disease. Associated with Kayser-Fleischer rings. 

===Wimberger sign===
In congenital syphilis, bilateral, symmetric destruction in upper medial tibias metaphyses. May also be seen in bacterial osteomyelitis, hamartomosis, hyperparathyroidism. 

===Winslow, foramen of===
Omental foramen between abdominal cavity and omental bursa, bounded anteriorly by the portal triad; posteriorly by the IVC and right crus of diaphragm; superiorly by the caudate lobe; and inferiorly by the superior part of duodenum, portal triad. 

===Winterbottom's sign===
In West [[African trypanosomiasis]] (sleeping sickness, caused by Trypanosoma brucei gambiense, humans primary reservoir), classic finding of posterior cervical triangle lymphadenopathy; described by Thomas Winterbottom who noted that slave traders in late 18th century used neck swelling as indicator of sleeping sickness in slaves. 

===Winter's formula===
Gives expected pCO2 from respiratory compensation in uncomplicated metabolic acidosis; expected CO2=[HCO3]*1.54 + 8.36. 

===Wintrobe indices===
Mean cell volume; mean cell hemoglobin; mean cell hemoglobin concentration. 

===Wirsung, duct of===
Duct embryologically confined to the ventral pancreas, becomes functionally the main pancreatic duct after duct fusion occurs. Drains the bulk of pancreatic secretion through the major papilla. 

===Wiskott-Aldrich syndrome===
X-linked characterized by triad of eczema, thrombocytopenia (from autoantibodies), and repeated infections; small platelets (3-5 fL); failure to express sialic acid-rich glycoprotein, sialophorin or CD15. Treatment primarily supportive and can include hematopoietic stem cell transplant. Due to mutation in WASP gene. 

===Wohlfart-Kugelberg-Welander disease===
Spinal muscular atrophy type III, presents in late childhood, runs a slow, indolent course, weakness greatest in proximal muscles, autosomal recessive or autosomal dominant, survival motor neuron protein affected. 

===Wolff-Chaikoff effect===
When increasing doses of iodide inhibit organification and hormonogenesis of thyroid hormone. 

===[[Wolff-Parkinson-White syndrome]]===
Paroxysmal supraventricular tachycardia caused by conduction through abnormal accessory bypass tract (bundle of Kent) between atria and ventricles characterized by triad of (1) wide QRS complex, (2) relatively short PR interval, and (3) slurring of initial part of QRS delta wave; in familial WPW, associated with mutation in gamma2 regulatory subunit of AMP-activated protein kinase (PRKAG2). 

===Wolf-Hirschhorn syndrome===
Deletion 4p syndrome, from de novo deletion of 4p16.3 to 4pter; associated with growth and mental deficiency, seizure disorder, prominent glabella, among other features. 

===Wolfram syndrome===
Diabetes insipidus and mellitus with optic atrophy and deafness, also referred to as DIDMOAD; diabetes is non-autoimmune; caused by mutation in gene encoding wolframin. 

===Wollfian duct===
In male embryonic development, duct that gives rise to epididymis, vasa deferentia, seminal vesicles, and ejaculatory ducts. 

===Wolman disease===
Lysosomal storage disease. Autosomal recessive, from lysosomal acid lipase deficiency, resulting in impaired hydrolysis of cholesteryl esters and triglycerides in the lysosome leading to mild mental retardation, hepatomegaly, adrenal calcification, fatal in infancy with inanition, malabsorption, and intractable diarrhea. 

===Woodruff's plexus===
Site for posterior epistaxis; made up of anastamoses between branches of the internal maxillary artery; located where the sphenopalatine artery enters the nasal cavity through the sphenopalatine foramen at the posterior limit of the middle turbinate. 

===Wood's lamp===
Lamp that emits UV light. 

===Wood's maneuver===
In management of shoulder dystocia, rotating posterior shoulder 180 degrees. 

===Woolf's syndrome===
Autosomal dominant syndrome with albinismus circumscriptus and deaf-mutism without other features of Waardenburg's syndrome. 

===Word catheter===
A catheter with an inflatable balloon tip used for draining cysts, e.g. [[Bartholin gland abscess]]; described by Word in 1968. 

===Woronets trait===
Autosomal dominantly-inherited trait characterized by small population of markedly distorted red blood cells resembling keratocytes; normal RBC life span. 

===Wright's maneuver===
In thoracic outlet obstruction: evaluating the radial pulse at the wrist with the shoulder in external rotation and abduction, positive sign if it reproduces shoulder and arm symptoms and obliterates radial pulse. 

===Wright's stain===
Stain used for blood and bone marrow films. 

===Wrisberg's ligament===
Posterior meniscofemoral ligament. 

===Wunderlich's syndrome===
Spontaneous renal bleeding of non-traumatic origin, confined to the subcapsular and perirenal space. 

===Wyburn-Mason syndrome===
Arteriovenous malformations in both the central nervous system and the retina; also known as Bonnet-Dechaume-Blanc syndrome. 


==X==

==Y==
===Yerganson's Sign===
*Pain and weakness with resisted supination
*Common in Biceps Tendonitis

==Z==
===Zhan, Infart of===
In occlusion of an intrahepatic branch of portal vein, sharply demarcated area of red-blue discoloration, not infarct, not necrosis, only marked stasis in distended sinusoids, with secondary hepatocellular atrophy. 

===Zahn, Lines of===
Thrombi formed within a cardiac chamber or the aorta, may have apparent laminations, produced by alternating layers of paler platelets admixed with some fibrin, separated by darker layers containing more red cells. 

===Zavanelli maneuver===
For management of shoulder dystocia, cephalic replacement of infant followed by caesarian delivery. 

===Zellweger syndrome===
Disorder of peroxisomes characterized by the congenital absence of functioning peroxisomes resulting in a cerebrohepatorenal syndrome; associated with prenatal development problems, hepatomegaly, increased serum iron and copper, visual disturbances; generally fatal by 1 year; caused by mutations in genes involved in peroxisome biogenesis (PEX genes). 

===[[Zenker's diverticulum]]===
A pharyngeal diverticulum from premature contraction of the cricopharyngeus muscle on swallowing, leads to progressive UES narrowing, leading to a posteriorly directed hypopharynx; causes progressive food stasis and dysphagia.

===Zieve's syndrome===
Jaundice, hyperlipemia, and hemolytic anemia in alcoholic liver disease; described in 1958.<ref>Zieve, L. "Jaundice, hyperlipemia and hemolytic anemia: a heretofore unrecognized syndrome associated with alcoholic fatty liver and cirrhosis". Annals of Internal Medicine 48 (3): 1958. 471–476</ref>

===[[Zika virus]]===
Mosquito-borne flavivirus, usual asymptomatic, can cause viral prodromal syndrome, birth defects if pregnant woman infected
 
===Zinn, annulus of===
Ring of fibrous tissue that surrounds the optic foramen, where the optic nerve enters at the apex of the orbit. Serves as the origin of five of the six extraocular muscles.

===[[Zollinger-Ellison syndrome]]===
Circulating hypergastrinemia seen in gastrinoma. Associated with gastric acid hypersecretion and severe peptic ulcer diathesis. Associated with peptic ulcers and diarrhea; 60% malignant, only 20% resectable; 25% of gastrinoma patients have multiple endocrine neoplasia type I; >80% of gastrinomas found in gastrinoma triangle.

===Zoon's balanitis===
Plasma cell balanitis (also known as balanitis circumscripta plasmacellularis), idiopathic, rare, benign, penile dermatosis with plasma cell infiltration; treated with circumcision; described in 1952. 

===Zuckerkandl, organ of===
Collection of para-aortic, paraganglion cells around the origin of the inferior mesenteric artery; a site where extra-adrenal pheochromocytomas may arise. 

===Zuckerkandl, tubercle of===
Part of thyroid that tracts posterior to the sides of the trachea and esophagus; found in nearly 2/3 of patients undergoing thyroid surgery, usually enlarges lateral to recurrent laryngeal nerve; described in 1902.


==See Also==
*[[Eponyms (A-B)]]
*[[Eponyms (C-E)]]
*[[Eponyms (F-L)]]
*[[Eponyms (M-P)]]
*[[Eponyms (Q-S)]]


==References==
<references/>
[[Category:Misc/General]]