Pathognomony

Pathognomony means characteristic for a particular disease. A pathognomonic sign is a particular sign whose presence means that a particular disease is present beyond any doubt. Labeling a sign or symptom "pathognomonic" represents a marked intensification of a "diagnostic" sign or symptom.

Disease	Sign
Cytomegalovirus infection	Owl's eye appearance of inclusion bodies
Lyme Disease	Erythema chronicum migrans
Inclusion body myositis	Filamentous material seen in inclusion bodies under electron microscopy
Hypocalcemia	Trousseau sign and Chvostek sign
Tetanus	Risus sardonicus
Bulimia Nervosa	Chipmunk facies (parotid gland swelling) (Chipmunk facies also seen in marrow expansion secondary to Beta Thalassemia Major)
Leprosy	Leonine facies (thickened lion-like facial skin) (Lionine facies also seen in Paget Disease of bone)
Measles	Koplik's spots
Diphtheria	Pseudomembrane on tonsils, pharynx and nasal cavity
Chronic hemorrhagic pancreatitis	Grey-Turner's sign (ecchymosis in flank area)
Cholera	Rice-watery stool
Enteric fever	Rose spots in abdomen
Meningitis	Kernig's sign and Brudzinski's sign
Cholecystitis	Murphy's sign (pain on deep inspiration when inflamed gallbladder is palpated)
Angina pectoris	Levine's sign (hand clutching of chest)
Patent ductus arteriosus	Machine-like murmur
Pleural Effusion	Stony-dull percussion
Parkinson's disease	Pill-rolling tremors
Whipple's disease	Oculo-Masticatory Myorhythmia
Acute Myeloid Leukemia	Auer rod
Multiple Sclerosis	Bilateral internuclear ophthalmoplegia
Congestive heart failure	Third heart sound
Pericarditis	Pericardial friction rub
Neurofibromatosis I	Plexiform neurofibroma
Hodgkin's lymphoma	Pain within minutes after drinking alcohol.  Reed-Sternberg cells (giant mono- and multinucleated cells).
Pyelonephritis	White blood cell casts
Rheumatic fever	Aschoff nodules
Rabies	Hydrophobia and Negri bodies

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