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Introduction – Hepatitis A Hepatitis A is a liver disease caused by the hepatitis A virus (HAV). The virus is primarily spread when an uninfected (and unvaccinated) person ingests food or water that is contaminated with the feces of an infected person. The disease is closely associated with unsafe water …

What is Hantavirus pulmonary syndrome? The term hantavirus represents several groups of RNA-containing viruses (that are members of the virus family of Bunyaviridae) that are carried by rodents and can cause severe respiratory infections termed hantavirus pulmonary syndrome (HPS) and hemorrhagic fever with renal syndrome (HFRS). HPS is found mainly …

Hypertensive Heart Disease – Definition Hypertensive heart disease is characterized by a firmly continuous high blood pressure in which the force of blood against the artery walls is too high. Continuous hypertension causes structural and functional abnormalities of the heart. This can also cause damage to the ventricular and arterial …

Herpetic Whitlow – Overview Herpetic whitlow is a painful hand infection or lesion that typically involves one or more fingers. It is usually caused by herpes simplex virus 1, but occasionally it is caused by the herpes simplex virus 2. It usually afflicts health care workers, such as dentists. The …

Description – Hypersensitivity Pneumonitis Hypersensitivity pneumonitis (HP), also called extrinsic allergic alveolitis, is a respiratory syndrome involving the lung parenchyma and specifically the alveoli, terminal bronchioli, and alveolar interstitium, due to a delayed allergic reaction. Such reaction is secondary to a repeated and prolonged inhalation of different types of organic …

Hematuria – Overview Blood in urine – known medically as hematuria – is usually not a reason for major alarm. Because blood in urine can be a sign of a serious medical condition, however, it shouldn’t be ignored. All cases of hematuria should be evaluated by a doctor who can …

Overview A hernia occurs when an organ pushes through an opening in the muscle or tissue that holds it in place. For example, the intestines may break through a weakened area in the abdominal wall. Hernias are most common in the abdomen, but they can also appear in the upper …

Definition Hyperhidrosis, which is sweating in excess of that required for normal thermoregulation, is a condition that usually begins in either childhood or adolescence. Although any site on the body can be affected by hyperhidrosis, the sites most commonly affected are the palms, soles, and axillae. See the image below. …