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Definition A pulmonary embolism (PE) is a blood clot that develops in a blood vessel in the body (often in the leg). It then travels to a lung artery where it suddenly blocks blood flow. A blood clot that forms in a blood vessel in one area of the body …

Definition Panniculitis is a broad term referring to inflammation of the fatty layer underneath the skin. It is usually seen in women, on the thighs and lower legs. There are many types of panniculitis, all with different causes, but the condition generally causes the skin to feel hard and to …

Overview Phimosis is defined as the inability to retract the skin (foreskin or prepuce) covering the head (glans) of the penis. Phimosis may appear as a tight ring or “rubber band” of foreskin around the tip of the penis, preventing full retraction. Types of Phimosis                          Phimosis is divided into two …

Definition Peeling skin syndrome is a group of rare inherited skin disorders characterized by painless, continual, spontaneous skin peeling (exfoliation) due to a separation of the outermost layer of the epidermis (stratum corneum) from the underlying layers. Other findings may include blistering and/or reddening of the skin(erythema) and itching (pruritus). …

Description Progressive multifocal leukoencephalopathy (PML) is a disease of the white matter of the brain, caused by lytic infection of oligodendrocytes by the JC polyomavirus (JCV) that targets cells that make myelin – the material that insulates nerve cells (neurons). This etiological virus was isolated and identified during the brain …

Definition Pterygium means “wing” and refers to a wing-like growth on the surface of the eye.  It (growth) spreads from the conjunctiva over the cornea. The conjunctiva is the mucous membrane covering the whites of the eyes (sclera) and the cornea is the clear windshield of the eye.  Pterygia are …

Definition Paroxysmal nocturnal hemoglobinuria or PNH is a rare and chronic disease that results in an abnormal breakdown of red blood cells. PNH is due to a spontaneous genetic mutation that causes red blood cells to be deficient in a protein, leaving them fragile. Because the kidneys help to filter …

Definition Preeclampsia is defined as the presence of a systolic blood pressure (SBP) greater than or equal to 140 mm Hg or a diastolic blood pressure (DBP) greater than or equal to 90 mm Hg or higher, on two occasions at least 4 hours apart in a previously normotensive patient. …