The portal uses cookies to provide service functions such as “Bookmark” and to improve website usage. Information and opt-out options can be found in the cookie settings in the privacy policy.

Search
Immune system: doctor palpating a woman’s cervical lymph nodes. The woman is looking up and appears tense.

Conditions Immune system

The immune system protects the body from diseases by combating hazardous substances and pathogens. However, this complex system is far from immune to disorders of its own. Both depressed and overactive immune responses can make people ill, for example by causing autoimmune diseases. Inappropriate immune responses can also cause allergies.

Immune system

HIV: piles of brightly-colored condoms. HIV: piles of brightly-colored condoms.

HIV and AIDS

The HIV virus infects immune cells and weakens the immune system. The serious illnesses caused by HIV are called AIDS.

A doctor dropping liquid from a pipette onto a man’s forearm. Lines and test areas are marked out on the arm. A doctor dropping liquid from a pipette onto a man’s forearm. Lines and test areas are marked out on the arm.

Allergies

An allergy occurs when the immune system has an overly sensitive reaction to a harmless substance such as plant pollen. There are various ways to treat an allergy.

A doctor holding a patient’s hand to examine it. A stethoscope is lying on the table. A doctor holding a patient’s hand to examine it. A stethoscope is lying on the table.

Rheumatoid arthritis

Rheumatoid arthritis typically causes chronic inflammation of multiple joints. As a result, the joints can become deformed and stiff over time.

Rosacea: woman’s cheek slightly reddened. There are red veins visible in her eye. Rosacea: woman’s cheek slightly reddened. There are red veins visible in her eye.

Rosacea

Rosacea, a common inflammatory disease of the facial skin, causes redness, pustules, and small visible blood vessels on the face.

A middle-aged woman sitting in a wheelchair takes care of her flowers using a hand gripper. A middle-aged woman sitting in a wheelchair takes care of her flowers using a hand gripper.

Multiple sclerosis

Multiple sclerosis (MS) is the most commonly occurring neurological disease in young adults. At present, there is no cure for MS. However, various treatments help to slow its progression.

A woman holding an asthma inhaler in her hand. A woman holding an asthma inhaler in her hand.

Asthma

Asthma is a condition that causes a narrowing of the airways. An asthma attack can make it difficult to breathe. Asthma can be treated effectively with medication.

Type 1 diabetes: doctor holding a blood glucose meter to a woman’s finger tip. Type 1 diabetes: doctor holding a blood glucose meter to a woman’s finger tip.

Type 1 diabetes

With type 1 diabetes, the pancreas produces very little or no insulin. To supply the body with this essential hormone, people with the disease need daily injections of insulin.

Acne inversa

Acne inversa (hidradenitis suppurativa) is a chronic inflammatory skin condition. It causes issues such as painful nodules and abscesses. Find out what can be done to help combat it.

A woman sits bent forward on the toilet, holding a roll of toilet paper in her hand. A woman sits bent forward on the toilet, holding a roll of toilet paper in her hand.

Crohn’s disease

Crohn’s disease is a chronic disease involving inflammation of sections of the digestive system. Read on to find out what causes it and which treatment options are available.

Psoriasis: man bending his arms next to his upper body and showing his elbows. There is psoriasis on both elbows. Psoriasis: man bending his arms next to his upper body and showing his elbows. There is psoriasis on both elbows.

Psoriasis

Psoriasis is an inflammatory, non-contagious skin condition. It is characterized by reddish, flaky skin that may be itchy.

Neurodermatitis: woman rubbing cream into her hand. Neurodermatitis: woman rubbing cream into her hand.

Neurodermatitis

People with neurodermatitis often get a rash and a nagging itching. This skin condition often occurs in children. Learn more about neurodermatitis and the treatment options.

Nesselsucht: Die nackten Beine eines Menschen sind mit einem Ausschlag überzogen. Der Ausschlag ist leicht rötlich und wirkt geschwollen. Nesselsucht: Die nackten Beine eines Menschen sind mit einem Ausschlag überzogen. Der Ausschlag ist leicht rötlich und wirkt geschwollen.

Urticaria

Urticaria (hives) is a skin condition with which itchy wheals or a painful swelling of the hypodermis (angiodema) form. Read more about symptoms, progression, and treatment.

A man sneezing into a tissue. A man sneezing into a tissue.

Hay fever

Many children and adults are affected by hay fever in the spring and summer months, when plants grow and bloom. It is caused by an allergic reaction to pollen in the air, affecting the upper airways.

A woman is having her heart listened to. A woman is having her heart listened to.

Acute myocarditis

Acute myocarditis (inflammation of the heart muscle) can be a rare consequence of an infection. There are mild but also life-threatening forms.

A doctor examines a brain scan on a monitor. A doctor examines a brain scan on a monitor.

Encephalitis (inflammation of the brain)

Encephalitis is an inflammation of the brain. It can have several causes, the most frequent being viruses.

Contact allergy: thumb pressing nozzle on contact spray bottle; spray released. Contact allergy: thumb pressing nozzle on contact spray bottle; spray released.

Contact allergy

A contact allergy can cause severe skin reactions. The symptoms only become noticeable after 1 to 3 days.

A woman is sitting on a chair with a black cat on the backrest. She is holding a tissue to her face with one hand. A woman is sitting on a chair with a black cat on the backrest. She is holding a tissue to her face with one hand.

Animal allergy

In an animal allergy it is not the fur that causes a reaction, but proteins that are found in the animal’s saliva, for instance. Avoiding contact with the animal can help, as can taking medication.

Oral thrush is caused by a fungus, specifically the various types of Candida fungus. Oral thrush is caused by a fungus, specifically the various types of Candida fungus.

Oral thrush (oral candidiasis)

If a person’s mouth constantly feels furry, it may be caused by oral thrush. It is rarely dangerous, but often unpleasant.

Dust mite allergy: woman dusting and holding her hand over her face. Her eyes are reddened. Dust mite allergy: woman dusting and holding her hand over her face. Her eyes are reddened.

Dust mite allergy

In dust mite allergies, it isn’t the dust itself that causes the symptoms. Instead, the symptoms such as sneezing are triggered by substances that are mainly found in the dust mites’ feces.

A girl is looking at a bee on her hand. A girl is looking at a bee on her hand.

Insect venom allergy

Insect stings or bites usually leave behind nothing more than a small red mark. But someone who has an insect venom allergy will react very severely. This can even become a life-threatening situation.

Food allergy: a boy sitting at a table in front of a bowl of peanuts. Food allergy: a boy sitting at a table in front of a bowl of peanuts.

Food allergy

People with a food allergy usually react to even very small quantities. What are the typical symptoms? How is a food allergy treated?

A woman lies exhausted on the couch. A woman lies exhausted on the couch.

Chronic fatigue syndrome

Chronic fatigue syndrome refers to severe fatigue that does not improve despite rest. There is no specific cure, but various measures that can help.

A doctor examines a patient’s ankle A doctor examines a patient’s ankle

Psoriatic arthritis

Psoriatic arthritis refers to inflammation of the joints as a result of psoriasis. It causes stiff and painful joints.

A doctor listens to a patient’s heart A doctor listens to a patient’s heart

Rheumatic heart disease

Auslöser der rheumatischen Herzkrankheit sind Streptokokken. Diese Bakterien verursachen akute Atemwegsinfektionen. In response, the immune system creates antibodies that may also attack and damage the heart.

A young girl is feeling ill and is lying on the sofa, being cared for by her grandmother. A young girl is feeling ill and is lying on the sofa, being cared for by her grandmother.

Antibody deficiencies

Antibodies play an important role in protecting the body from pathogens. An antibody deficiency weakens the immune system, resulting in frequent infections.

Hypothyroidism: woman clutching her throat. Hypothyroidism: woman clutching her throat.

Underactive thyroid

With an underactive thyroid, the thyroid gland does not produce enough hormones. This slows down the metabolism. People affected often feel lethargic, have a low heart rate and constipation.

Herpes labialis: young woman with cold sores on her upper lip. Herpes labialis: young woman with cold sores on her upper lip.

Oral herpes (cold sores)

With oral herpes, particular herpes viruses cause painful blisters known as cold sores to form. The condition heals on its own in 1 to 2 weeks. No treatment is normally required.

Vitiligo: woman holding a cup of tea in both hands. The pigmentation on her skin is normal apart from white patches on her hands and forearms. Vitiligo: woman holding a cup of tea in both hands. The pigmentation on her skin is normal apart from white patches on her hands and forearms.

Vitiligo

Vitiligo is a disorder that causes the loss of the brown skin pigment melanin. It usually begins as white skin patches on the face and hands. Read more about its causes and treatment.