A painful collection of pus anywhere in the body caused by bacterial infection is called abscess. This collection of the pus is within the tissue. While pressing, you can feel the swelling. There are mainly two types of abscess: - Skin abscesses: They develop under the skin - Internal abscesses: They develop inside the body, in an organ or in the spaces between organs. Among the two, skin abscess is more common.

Acoustic schwannoma, also known as Vestibular schwannoma, is an uncommon cancerous tumour in the nerve connecting the inner ear with the brain. Acoustic schwannoma can lead to hearing loss and unbearable pain in the ear. It can be treated by surgical removal, radiation and regular monitoring by the neurosurgeon specialist.

Acquired brain injury may occur through the sudden onset of trauma, infection, lack of oxygen, strokes, and drug use episodes, or through prolonged alcohol or substance abuse, and tumours or degenerative neurological diseases. Two thirds of all people with this disease are over the age of 45. One third of those are over the age of 65, and the largest age group is between 40 and 49. The disease is higher in men than women. Acquired brain injury is any damage to the brain affecting a person physically, emotionally or behaviorally. It can happen at birth or later, from an illness or trauma, and can be called traumatic or nontraumatic, depending on the specific cause. There could be many possible causes of it including road accidents, assaults, falls and accidents at home or at work, stroke, brain tumor, haemorrhage, or viral infection such as meningitis.

Acute Interstitial Nephritis is a common kidney disorder that causes swelling or inflammation in the kidney. The disease is often linked with certain infections, drug therapies or it may be caused by some unknown agent. Acute Interstitial Nephritis, if not treated properly, may lead to complete loss of kidney function and can be life threatening.

The kidneys in your body filter your blood to remove the waste and water from blood, maintain your blood pressure, clean the blood and stimulate your bone marrows to produce blood. Therefore, the kidneys play a pivotal role in your day-to-day life. In acute kidney injury, your kidneys are damaged and cease to function properly. The complications that arise from acute kidney injury could range from minor loss of kidney function to complete failure of the kidneys. Although the name suggests that it is an injury due to a physical blow to the kidneys, it usually happens as a result of other serious illnesses. Acute kidney failure is often seen in older people with other complications. If diagnosed in the early stages, ythe doctor can treat you to avoid complications later on. In case of delayed diagnosis, the level of salts and chemicals in blood will be abnormally high, owing to malfunctioning kidneys. This will affect not only your kidneys, but also the functioning of other organs. In case of a complete kidney failure, it is necessary to provide external aid from a dialysis machine. If ignored, acute kidney injury leads to death.

Acute myeloid leukemia (AML) is a type of cancer in which the white blood cells, red blood cells, and platelets are attacked by bone marrow, which is a soft inner part of the bones. Without proper treatment, acute myeloid leukemia can be fatal, as it can spread very quickly to the blood and other parts of the body. Fever, fatigue, and bleeding are symptoms of the disease. Leukemia mainly targets the red and white blood cells and platelets. Acute myeloid leukemia is also known as acute myelocytic leukemia, acute myelogenous leukemia, acute granulocytic leukemia, and acute non-lymphocytic leukemia. The disease can affect liver, brain, spinal cord, lymph nodes, and testicles

Acute renal failure, also called acute kidney failure, happens when the patient's kidney loses its ability to filter waste. Waste starts accumulating in the kidneys which disturbs the chemical makeup of the patient's blood. The condition requires intensive care and treatment.

The adrenal glands, present on the top of each of the kidneys, are responsible for producing hormones that regulate the body’s metabolism, immune system, blood pressure and other important functions. Addison's disease is a type of adrenal disorder that occurs when the adrenal glands produce insufficient amounts of hormones (cortisol and aldosterone). This condition arises when the outer layer (cortex) of the adrenal glands gets damaged. The disease can pose a threat to the patient’s life.

Adenoid hypertrophy (or enlarged adenoids) is the unusual enlargement of the adenoid tonsil. The inflammation is common in children, especially between age group 2-6 years. The enlargement of tissue can be either due to bacterial infection or physiological reason. Adenoids are lymph tissues, similar to tonsils located in the upper air way between the nose and back of the throat. Adenoids are a part of the immune system and help the human body fight against infection. Adenoids enlarge due to infection but normalize after the infection subsides. However, if they remain enlarged even after the infection has gone, it may create problems. One of the possible treatments is removing them from the body.

There are many layers of tiny cells present in Macula. As we grow older, these tiny cells do not function adequately. If they do not, then there is high probability of deposits building up in the retina. Also, new blood vessels will grow inside the retina. The new vessels are delicate, and often bleed easily. Under these different conditions, your retina will not function properly. You will have a distorted or blurred vision, and sometimes, no vision. AMD has been identified as a common condition affecting people more than 50 years old. In a few cases, AMD develops slowly, affecting people at a later stage. In other cases, its progression can be evidently faster. When Macula or central portion of your eye deteriorates, the condition is called Macular degeneration. It is medically acknowledged as an incurable eye disease. Under macular degeneration, an individual will not be able to see properly. In severe cases, the person will suffer total vision loss. When macula is damaged, its functioning process of recording the images and sending a brain signal via the optic nerve suffers. The prevalence of age-related macular degeneration is increasing in Asia due to increase in life expectancy and rising incidents of diabetes among the younger population. As per the Centre for Eye Research Australia, prevalence of diabetic retinopathy among people ranged between 17% and 22% in India, and 43.1% in rural China in 2012. Age-related eye diseases such as glaucoma, cataract, diabetic retinopathy, and age-related macular degeneration, are the leading causes of visual impairment and blindness in North America. According to the American Academy of Ophthalmology, approximately 22 million Americans aged 40 and above were affected by cataract and 2.3 million Americans were affected by glaucoma in 2011.

Agnosia is a neurological disorder which affects a single information pathway in the brain. This leads to disability in recognition of faces, voices, objects or places. However, people suffering from Agnosia can still interact with the world normally. As mentioned, Agnosia affects a single pathway when brain suffers certain damage. This pathway connects primary sensory areas that store knowledge and information. These primary sensory regions are mainly visual or auditory cortices. Agnosia is caused by lesions on the parietal or occipital lobes of the brain. There are different types of Agnosia, including Environmental Agnosia, Finger Agnosia, Integrative Agnosia and Topographical disorientation. The primary sensory regions are mainly visual or auditory cortices. Lesions on the parietal or occipital lobes of the brain cause Agnosia. These lobes are vital in storing schematic information and language. Strokes, head traumas, encephalitis, carbon monoxide poisoning, dementia or anoxia generally creates the lesions.

Allergic Rhinitis, commonly known as hay fever, is one of the most common allergic conditions, and occurs when the nasal cavity is exposed to foreign particles such as pollens, dust, etc. The person starts sneezing or develops a running nose on breathing something which the immune system is allergic to. It is also referred to as seasonal allergies and is triggered by grass, pollen, dust and dirt in the air, and at times because of smoke and perfumes. Allergic rhinitis is not severe or fatal until accompanied by asthma or anaphylaxis, which can be significant. Drugs namely Antihistamines is used to treat this disease, and together with other drugs, they make up a fraction of over-the-counter drugs, and is prescribed every year.

Alport syndrome refers to a kind of heterogeneous and inherited disorders that are connected with the basement membranes of kidneys. The syndrome also affects the eyes and cochlea. Statistically, Alport syndrome affects one in every fifty thousand children. The distinguishing features are hematuria, proteinuria, hearing loss, end-stage kidney disease, glomerulonephritis, and problems with eyesight. The three classifications of Alport syndrome are: autosomal recessive Alport syndrome (ARAS), X-linked Alport syndrome (XLAS), and autosomal dominant Alport syndrome (ADAS)

Alzheimer’s is a neurological disorder that leads to a gradual loss of memory with time. Initially, it may only cause minor forgetfulness like forgetting names of people, familiar places, directions followed by anxiety and confusion. Alzheimer’s is the most common form of dementia and is mostly seen in aged people. The disease limits one’s social interaction and gets extremely severe in its final stages.

Amblyopia, also known as lazy eye, is an early childhood disorder of sight where the development of a child’s eyesight is not proper. The main focus of the brain is more on one eye than the other, resulting in decreased eyesight in other eye. The visual brain cells don’t mature generally if that eye is not stimulated in a proper way. If not diagnosed and treated at an early stage, this condition may cause lifelong vision loss. When it comes to research reports, this condition is estimated to affect 2-3% of all children.

The Anaplastic astrocytoma is defined as an uncommon cancerous tumour in the brain. These tumours form from several brain cells that are shaped as a star and are known as astrocytes. Cells like astrocytes develop the tissue that nears and shields other nerve cells that are present in the spinal cord and the brain. Together, all these cells are called glial cells, and the glial tissue is the tissue that they develop. Astrocytomas are one of the tumors that come from glial tissues and known as gliomas. Anaplastic astrocytoma is a kind of brain cancer. This disease comes in the class of high-grade gliomas that are persistently analogous gliomas and that take an improper clinical prediction. This disease also lacks vascular multiplication. The tumours that are caused in this disease, comprise of cells that are both normal and abnormal. The two kind of astrocytomas are; low-grade astrocytomas and high-grade astrocytomas. The astrocytomas that have a tendency to grow slow are low-grade astrocytomas, whereas the ones which have a tendency to grow at a high pace are high-grade astrocytomas.

It is a form of hair loss which is seen both in men and women. In men, this condition is called male-pattern baldness. Baldness in men is more well-defined in comparison to women. In men, starting above the temples, the hairline starts receding eventually, causing partial or complete baldness. While in women, it causes thinning of the hairs, and rarely leads to complete baldness. Androgenetic alopecia is caused due to prolonged effect of androgen on the hair follicles. In some cases it might also be due to other factors like seasonal changes, malnutrition, anemia, etc.

Angina is a term used for pain and discomfort felt in your chest. Also known as angina pectoris, angina is mainly caused by coronary heart disease. It is normally discussed as pressure, heaviness, pain or tightness in your chest. The blood supply to your heart is confined due to the narrowing of the arteries that supply blood and oxygen to your heart muscle. It is often brought on by an emotional upset, physical exertion or after a meal. This condition requires urgent medical attention as it may precede heart attack

Angioedema, also known as Quincke’s edema is described as the rapid swelling of dermis (skin), mucus, and submucosal tissues. It usually affects the deeper part of the skin, commonly around the face and lips. It is also defined as an acute mast of cell–mediated reaction caused by exposure to drug, venom, pollen, or animal allergens. The swelling (localized) is due to vascular and intravascular fluid leakages. The skin around the eyes, lips, genitals, hands, and feet swell and develops into red, itchy patches called hives or urticaria on the skin surface. Angioedema is classified into two main types: Acquired Angioedema (AAE) and Hereditary Angioedema (HAE). AAE is usually caused by allergy, and can be a side-effect of certain medicines like ACE inhibitors. HAE is caused by genetic mutations inherited from the family. These are distinguished by underlying genetic abnormalities.

An ankle sprain is an injury that occurs in your ankles, when you twist, turn or roll your ankles at awkward angles. The bones of ankles are held together using a ligament and the injury damages these ligaments. If you have a sprained ankle, your ankle ligaments would have been moved beyond their normal range of motion. Usually, sprained ankles are associated with tearing of ligaments in the outer edges of the ankle. For injuries of lesser magnitude, over-the-counter medication may be sufficient. But depending on the extent of damages caused, it is always suggested that you consult a doctor for a thorough medical examination. If a grave injury is left untreated, an ankle sprain might lead to chronic pain, chronic ankle instability or arthritis in the ankle.

Anxiety disorders differ from normal feelings of nervousness and involve excessive fear or anxiety. Anxiety in particular also refers to anticipation of a future concern and is associated more with muscle tension and avoidance behavior. These disorders can cause people to avoid situations and places that might cause them to feel trapped, helpless, panicking, embarrassed, and scared. Job performance, school work, and personal relationships can be affected. Anxiety disorder is the most common of mental disorders affecting majority of population. For people who have it, worry and fear are constant and overwhelming. It is a serious mental illness, but proper treatment helps most people lead normal and productive lives.

The aorta of the human heart is the largest blood vessel in the human body. It is the carrier of oxygenated blood from the heart to all parts of our body. The aorta originates at the left ventricle of the heart and runs down all the way to the abdomen where it branches into three arteries. It helps push thousands of liters of blood into our body, during our lifetime. It is tough and durable, but sometimes, the walls of the aorta can weaken and burst, causing serious bleeding inside the body. This is called aortic aneurysm. Aortic aneurysm is of two types: Thoracic aortic aneurysm (when the weak segment of the aorta is found inside the chest area); and Abdominal aortic aneurysm (when the weak segment of the aorta is inside the abdominal cavity). Abdominal aortic aneurysm is the most common variety of aneurysm.

Aortic stenosis or aortic valve stenosis occurs when the aortic valve of the heart narrows down. The narrowing of the aortic valve stops it from opening completely, which obstructs the flow of blood from the heart into the aorta and the rest of the body. Under this condition, the heart needs to exert harder in pumping blood to the body. This exertion from the heart’s end might cause the heart muscles to weaken, limiting the amount of blood being pumped. If somebody has a severe case of aortic valve, they will need a surgery to replace the damaged valve, or else it can lead to grave heart problems. Aortic stenosis majorly affects old people, as the valve that is defective usually hardens and narrows down.

Arrhythmia is a complication with the rate of your heartbeat. It arises with the improper working of electrical impulses that correlate with your heartbeats, affecting your heart to beat too slow, too fast or irregularly. When the rate is too slow, it is called bradycardia. When the rate is too fast, it is called tachycardia. Many factors such as smoking, congenital heart defects and stress are majorly responsible for this condition. There are many effective treatments available that focus to recondition a normal heart rhythm.

Veins carry deoxygenated blood towards the heart and the arteries carry oxygenated blood from the heart to the brain. Arteriovenous Malformations interrupt this process. Arteriovenous Malfunctions may occur in the spinal cord, brain or the brain stream. The only main cause of Arteriovenous Malfunctions is a genetic disorder passed on by parents.

Ascites refers to the accumulation of serous pale yellow and clear fluid in the peritoneal or abdominal cavity, located below the chest cavity and separated from it by a diaphragm. The fluid could be a result of many complications including liver diseases, kidney failure, cancers and congestive heart failure. The basic principle is similar to formation of edema, owing to imbalance of pressure between the external and internal systems.

Anxiety disorders differ from normal feelings of nervousness and involve excessive fear or anxiety. Anxiety in particular also refers to anticipation of a future concern and is associated more with muscle tension and avoidance behavior. These disorders can cause people to avoid situations and places that might cause them to feel trapped, helpless, panicking, embarrassed, and scared. Job performance, school work, and personal relationships can be affected. Anxiety disorder is the most common of mental disorders affecting majority of population. For people who have it, worry and fear are constant and overwhelming. It is a serious mental illness, but proper treatment helps most people lead normal and productive lives.

Ataxia is known as a lack of muscle coordination which may affect speech, eye movements, the ability to swallow, walking, picking up objects, and other voluntary movements. Ataxia often describe symptoms of impaired coordination which can be associated with infections, injuries, or degenerative changes in the central nervous system. It is also used to denote a group of specific degenerative diseases of the nervous system, called the hereditary ataxias.

Your arteries are the carriers of blood from your heart to all the parts of your body. Generally, these arteries are flexible and elastic. But in atherosclerosis, your arteries become thick and stiff. Atherosclerosis refers to the building up of fats, cholesterol, etc. inside your arteries, forming plaques. These plaques could restrict the flow of blood by narrowing your arteries. Sometimes, the plaques could also rupture and burst, forming a blood clot. Even though it is a cardiac problem, an artery in any part of your body could be affected by atherosclerosis. This condition is both treatable and preventable. Depending on which artery is blocked, there could be various complications arising from atherosclerosis - Coronary artery disease – When the plaques build up in the arteries near the heart, it leads to coronary artery disease. This may lead to chest pain and heart attack. Carotid artery disease – When the plaques are closer to your brain, it is called carotid artery disease. This may lead to a stroke. Peripheral artery disease – When the plaques are developed in the arteries of hands and legs, the condition is referred to as peripheral artery disease. This disease could lead to insensitivity to heat and cold and in extreme cases, gangrene. Aneurysms – An aneurysm is a bulge in the walls of the artery and can happen anywhere in the body. Chronic kidney disease – If the plaques grow in the arteries that are near the kidney, they decrease the quantity of oxygenated blood that reaches the kidneys. Over a period of time, this could lead to complications in your excretory system.

Atrial fibrillation is an irregular and rapid heart rate that can increase your risk of stroke, heart failure and other cardiac complications. When atrial fibrillation happens, the atria and the ventricles or the upper and the lower chambers of the heart would not be synchronized with one another. It could either come sometimes and repeat at intervals or not go at all. By itself, atrial fibrillation may not be very dangerous. However, it is a complex situation of the heart that screams for attention, because it can lead to blood clots and blood blockages.

The atrial septal defect (ASD) is a hole in the wall between the two upper chambers of the heart. There are two types of defect associated with the atrial septal - large atrial septal defect and small atrial septal defect. The large atrial septal defect may cause a major damage to the heart and lungs, whereas small atrial septal defect may occur incidentally, and may not be harmful or cause a problem. An individual whose atrial septal defect remains undetected for some time might face a shorter span of life because of a heart failure, or blood pressure that is unreasonably high and might even affect the working of arteries in the lungs. The atrial septal defect occurs in the interatrial septum, allowing pulmonary venous return from the left atrium to pass directly to the right atrium. It is a heart defect that is present from birth.

This is a type of congenital defect in center of the heart, due to a combination of several problems related to the heart. Often associated with Down syndrome, this is also referred to as ‘endocardial cushion effect’ or ‘atrioventricular septal defect’. A heart has two upper and two lower chambers. The upper chambers also called the right and left atria, receive incoming blood. The lower chambers, also called the right and left ventricles, pump blood out of your heart. The valves of the heart are the gates that control the quantity and direction of blood flow. Around 1.5 lakh infants in India are born with congenital heart disease (CHD) and approximately 78,000 of them die because of lack of awareness and improper medical treatment. If not treated at the right time, this could result not only in high blood pressure, but also in heart failure. Generally, it is recommended to operate, to close the hole and reconstruct the valves surgically. Atrioventricular canal defect occurs when there are problems with the valves of the heart that regulate blood flow and there is a hole between the heart’s chambers. Your heart would, therefore, pump in excess of blood to the lungs, causing over-working of the heart in turn. Due to overwork, the muscles in the heart tend to enlarge. There are two types of atrioventricular canal defect: If the defect is between the two upper chambers, it is called ‘partial atrioventricular canal defect’; If the defect is between all the four chambers, it is called ‘complete atrioventricular canal defect’.