Dawson Disease, also known as Subacute sclerosing panencephalitis (SSPE), is a progressive neurological disorder. It is caused by a chronic persistent infection with measles virus that affects the central nervous system. The measles virus may remain inactive and dormant for extended time periods, and then may become activate for no specific reason. It causes brain inflammation and the death of nerve cells, and usually affects children and young adults. If untreated, Dawson disease can lead to death. Therefore, immediate medical attention is necessary as soon as the first sign of symptoms appear. Dawson disease can occur anywhere from 2 to 10 years after the original measles illness. In developing countries, such as India, 20 cases per year in a million are reported.

Degenerative disc disease is an aging associated condition, explaining the breakdown of an intervertebral disc of the spine. These pillow-like discs are responsible for protecting brain, vertebrae and other nerves. This naturally occurring condition may cause numbness, weakness and pain that radiates down the leg. The longer the disc degeneration left untreated, the more the chance of severe chronic pain and other spine problems.

Dengue is a viral infection transmitted by the bite of the female Aedes mosquito which breeds in free-standing water. It could be in your home, in potted plant trays, or even in your fridge. It can also be transferred to the unborn baby in a pregnant woman who is infected with the disease. Congenital dengue is an arboviral disease caused by four types of the dengue viruses (DENV 1-4). Congenital dengue can be dangerous if untreated. The disease can vary from mild to intense, and can take dangerous forms which include dengue shock syndrome and dengue hemorrhagic fever (DHF). DHF is also known as break bone fever.

Dental abscess is a medical condition caused by bacterial infection. In dental abscess, pus formation occurs inside teeth or gums, or in the bones that keeps the teeth in place. The types of abscess are: Periapical abscess (abscess of teeth), Periodontal abscess (abscess of gums). Dental abscesses are not always painful, but need medical attention. The condition does not improve on its own and may spread, affecting other body parts. This infection generally happens when you have a tooth decay and it goes untreated. This infection occurs from a cracked tooth, where the dental pulp develops and is exposed to the oral environment. Our mouth is full of plaque (a biofilm or mass of bacteria that grows on surfaces within the mouth) which helps break down food with the help of acids, forming a sticky substance when combined with saliva. If the acid produced is not cleaned or removed, it can damage tooth enamel, which causes dental abscess.

Dental caries are cavities or holes (a type of structural damage) in the teeth. Cavities are formed due to tooth decay which occurs as a result of bacterial infections. Certain types of bacteria produce acids that affect or erode the tooth enamel and the underlying layers, called dentin. This acid is produced when the sugar concentration in the food and drinks reacts with the bacteria present in the plaque. The acid produced leads to a loss of calcium and phosphate from the enamel, and this process is called demineralisation. Salivary bacterial level is related to the oral infection among a lot of children. Strategies for effective management of this disease in early childhood includes risk management, brushing with a toothpaste that is fluoridated, and certain behavioural interventions that affect self-care exercises.

Dental Malocclusion is a condition in which your teeth are misaligned. It happens when your upper jaw and teeth overlap the lower jaw and teeth. The condition is also known as crowded teeth, misaligned teeth, crossbite, overbite, underbite, and open bite. In this condition, the teeth are not able to perform their normal function. If left untreated, it can lead to complex oral health conditions, including digestive problems.

Diabetes refers to an illness that influences how your body utilises the blood sugar known as glucose. The sugar is an important source of energy for the cells that make up your muscles and tissues. It is also vital for your brain as glucose is the main source of energy for the brain. Diabetes is known as an ailment of the pancreas (an organ behind your stomach that creates the hormone insulin). If a person is diabetic, the pancreas either cannot produce enough insulin or utilise the insulin properly. Insulin works with glucose in the circulation system to help it enter the body's cells to be burned for energy. If you are diabetic, regardless of what sort, it implies you have excess glucose in your blood which can lead to medical issues.

Diabetic foot infection is an open sore that usually does not heal, and may lead to serious complications. In many cases, they take form of ulcers and provide an entry route for bacteria which causes infections. They are basically a common complication of poorly controlled diabetes, forming as a result of skin tissue breaking down and exposing the layers underneath. Neuropathy can also cause structural deformities that can compound minor injuries to the foot. Diabetic foot infection is defined as soft tissue or bone infection below the malleoli, and are most commonly seen to occur under the big toes and the balls of the feet, affecting the feet severely.

Diabetic nephropathy, popularly known as diabetic kidney disease, is the medical conditions in the kidney that results in malfunctioning of the kidneys, owing to diabetic condition. Researchers have shown that around 30 percent of those with diabetes are susceptible to diabetic kidney disease. This condition ultimately results in failure of the kidney. In this disease, the glomeruli or the filters of the kidneys get damaged. Therefore, the kidneys would become incapable of filtering out the wastes from your blood. As a result, your urine will have high levels of proteins called Albumins. Healthy kidneys flush out tiny quantities of albumin in the urine. Therefore, diagnosis of higher levels of albumin is the sign that diabetic kidney disease exists. Coupled with other conditions like high blood pressure, high cholesterol or other diseases of the blood and heart, the damages incurred to the kidney are more and cause infections in the bladder and nerve damages. Depending on how much albumin is in the urine, there are two types of diabetic kidney disease: Microalbuminuria – The albumin level in urine is 30-300 mg per day Macroalbuminuria - The albumin level in urine is more than 300 mg per day

Diabetic Retinopathy (DR) is a diabetic complication which targets the eye. It is mostly caused by the damage of light sensitive tissues that are present at the back of the eye. It is the most common cause of vision blindness and impairment among adults. Swelling and distortion of macula is also a reason for the most common complications of retinoplasty. Diabetic eye disease is the primary cause of vision loss. Of an estimated 285 million people with diabetes mellitus worldwide, approximately one third have signs of DR and of these, a further one third of DR is vision-threatening DR, including diabetic macular edema (DME).

The spinal cord is very important because they hold the nerves from the brain. These nerves travel between the vertebrae to relay messages to all parts of the body. The spinal cord is made up of many bones called vertebrae. Between vertebrae are discs made up of strong rubber-like tissues. These discs are quite flexible and they in turn impart flexibility to the motion of the spinal cord. Strong ligaments of the vertebrae provide additional support and strength to the spine. A disc contains a soft material called nucleus pulposus enclosed in a strong layer of outer fibres. A disc prolapse refers to the process of rupturing of the nucleus, when there is an injury to the outer fibres. The soft material of the nucleus then enters the spinal nerves or the spinal canal. This process may either occur gradually over a long period of time or happen suddenly.

The chronic lack of adequate lubrication and moisture on the surface of the eye can result in a condition called dry eye syndrome. Dry eye occurs when the eye does not produce tears properly, or when the tears are not in consistency and evaporate too quickly. In addition, inflammation of the surface of the eye may occur along with dry eye. If left untreated, this condition can lead to pain, ulcers, or scars on the cornea, and also result in some loss of vision. However, permanent loss of vision from dry eye is uncommon. Dry eye can make it more difficult to perform some activities, such as using a computer or reading for an extended period of time. It can also decrease tolerance for dry environments, such as the air inside an airplane.

Dyspepsia is a medical condition caused by the abnormal functioning of the gastrointestinal organs, primarily the stomach and esophagus (the initial part of the small intestine). It a chronic disease, and the symptoms may vary from person to person, and in frequency and intensity. It is a condition which causes pain and discomfort in the upper abdomen. It is caused by acid in the stomach coming into touch with the mucosa of the digestive system. Dyspepsia is a group of symptoms which often include bloating, nausea and burping. The sensation that you get, appears immediately after consuming food and drinks. One can easily relieve their symptoms of dyspepsia, by making significant changes to their lifestyle.

Dysphagia means unsystematic eating. It is the medical term given to a swallowing disorder where people have a hard time swallowing, and choke on their food or liquid when trying to swallow. It is a kind of sensation that indicates obstruction in the passage of solids or liquids from the mouth to the stomach. This disorder may also be associated with severe pain. Occasional difficulty in swallowing occurs when something is eaten too fast or the food is not chewed well enough, which is not usually a cause of concern while persistent dysphagia may indicate a serious medical condition requiring treatment.

Dystonia is a condition that is identified by contractions of the involuntary muscles which cause movements of a repetitive nature. A person might sense painful movements and experience tremors. There are various types of dystonia that are genetic in nature. Dystonia is thought to be a neurological condition, caused by problems of the nervous system. However, in most cases, brain functions such as intelligence, memory, and language remain unaffected. Primary dystonia is mainly hereditary and its generalized form is the most difficult to live with and treat. Dystonia is not associated with problems in thinking or understanding, but depression and anxiety may be present. There are five types of dystonia: Focal dystonia - affecting muscles around the eyes, in the neck, in the throat, or in one of the limbs. Segmental dystonia - affecting an area of the body, such as the neck and an arm. Hemidystonia - affecting the arm and leg on one side of the body. Multifocal dystonia - affecting two or more parts of the body that aren’t connected, such as the left arm and leg. Generalised dystonia – affecting both legs and other regions of the body.