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Praxisklinik für Diagnostik

Medizinisches Versorgungszentrum

Private and all statutory insurance patients


Städelstraße 10

60596 Frankfurt am Main

Newsletter on special topics


Our specialists have written newsletters, which do not follow any particular order, containing FAQs and topics of current importance for our patients. These will continuously gather useful information about internal medicine for you.


The contributions do not claim to be exhaustive; they complement consulting your family doctor or the physicians at PKD.

  • Diabetes mellitus

    There are currently more than 7 million people being treated for diabetes mellitus in Germany of whom about 90% suffer from type 2 diabetes and about 5-10 % from type 1 diabetes. The number of type 2 diabetics, in particular, has been steadily increasing for years due to an ever growing number of overweight people as a result of changed eating habits and a lack of exercise.



    The sugar metabolism of healthy people


    Glucose is a type of sugar and a by-product of carbohydrates taken up with food, decomposed by enzymes in the digestive tract and absorbed into the bloodstream through the intestinal walls.

    The sugar metabolism is mainly regulated by two hormones - insulin and glucagon – that are both produced in the pancreas. Insulin, as a chemical messenger, is responsible for the transportation of glucose into the cells where it is consumed to produce energy. In addition, insulin causes the storage of glucose in form of glycogen in the liver and muscle cells, which helps maintain the blood sugar level of healthy people after eating within narrow limits (60-140 mg/dl or 3.3-7.7 mmol/l).


    What actually is diabetes mellitus?


    The term diabetes mellitus refers to a group of metabolic disorders under which the blood sugar level is constantly elevated. The blood sugar limit for patients with an empty stomach is at over 126 mg/dl (7.0 mmol/l) or/and at over 200 mg/dl (11.1 mmol/l) after eating. Causes of diabetes mellitus are an absolute insulin deficiency (type 1) or a relative insulin deficiency due to a reduced efficiency of insulin = insulin resistance (type 2) or both at the same time. A genetic predisposition accounts for most forms of diabetes mellitus.


    The guidelines of the German Diabetes Association name the following types:


    • Type 1 diabetes mellitus: the destruction of beta cells in the pancreas leads to an absolute insulin deficiency. There are often so-called antibodies against endogenous tissue detectable in the blood, which is why this form is also considered an autoimmune disease. Type 1 mostly manifests before patients turn 40.

    • Type 2 diabetes mellitus: this form is due to an insulin resistance with a relative insulin deficiency. At a later stage of the disease, an additional absolute insulin deficiency can partly occur. This form of diabetes often affects overweight people and is mostly associated with other problems of the metabolic syndrome (e.g. dyslipidemia, high blood pressure, increased levels of uric acid in the blood).

    • diabetes mellitus in association with other pancreas diseases (e.g. through inflammatory processes or after surgery).

    • diabetes mellitus in association with other metabolic diseases or hormonal disorders (e.g mucoviscidosis, hemochromatosis, PCOS or adrenal gland tumors).

    • diabetes mellitus in cases of genetic deficiencies (e.g. MODY).

    • diabetes during pregnancy (gestational diabetes) is a glucose tolerance disorder occurring for the first time in patients during pregnancy.


    Why is an increased blood sugar level a problem?


    A heavy increase of the blood sugar level (to over 250 mg/dl or higher) within a short period of time (hours up to days) because of a malfunction in its regulation can lead to a life-threatening situation that needs immediate treatment at a hospital. The body then increasingly excretes sugar and also water through the kidneys. Due to the extreme loss of fluids, the body might completely dehydrate – a dangerous state that can even lead to a diabetic coma in the worst of all cases. Warning symptoms are an excessive thirst, a frequent urge to pass water and fatigue.


    In cases of type 1 diabetes, abnormal blood sugar levels also reduce the body’s fat reserves to produce energy. Ketones are built that eventually lead to an excessive acidity of the blood, a so-called ketoacidosis. Warning symptoms are fatigue, nausea, vomiting and stomach pain.


    If the blood sugar level remains significantly elevated over a longer period of time it may harm other organ systems. The large and small blood vessels (arteriosclerosis) as well as the nerves can be affected in particular. As a consequence, secondary diseases such as circulatory disturbances of the coronary blood vessels (angina pectoris, heart attack), of the neck and brain arteries (stroke), the leg arteries (intermittent claudication), the eyes (visual loss until complete loss of sight) or the kidneys may develop.


    How to detect diabetes


    Diabetes is often detected by happenstance while getting a preventive checkup as only massively elevated blood sugar levels will show symptoms such as heavy thirst, a frequent urge to pass water or a loss of power.


    If a blood test reveals an elevated level of blood sugar of more than 126 mg/dl (7.0 mmol/l) for a patient with an empty stomach or/and more than 200 mg/dl (11.1 mmol/l) after eating diabetes mellitus will be the diagnosis.

    In addition, diagnostics will also measure the HbA1c value which shows the average blood sugar level of the last 3 months. An HbA1c level of 6.5% or above confirms the diagnosis of diabetes mellitus. HbA1c in the gray area between 5.7 and 6.4% will make an oral glucose tolerance test (OGTT) necessary in which the patient has to drink a sugar solution and then undergo a test with a venous blood sample taken after 2 hours.




    How to treat diabetes


    Treatments differ with the forms of diabetes. Type 1 diabetes requires an immediate treatment with insulin due to the complete lack of an endogenous insulin production. It is administered by means of an insulin pen or an insulin pump into the subcutaneous fat tissue.


    Type 2 diabetes often starts with an increased endogenous insulin production and a reduced sensitivity of the receptors for endogenous insulin at the muscle and fat cells. This is called insulin resistance. Reducing the patient’s body weight and calorie uptake while getting sufficient exercise may then help normalize the blood sugar level. If these measures are not enough medication will become necessary to improve the insulin sensitivity or stimulate the insulin production. After a longer time of suffering from type 2 diabetes (about 10-15 years) the endogenous insulin production will be exhausted though, and a treatment with insulin becomes necessary.


    Diabetes that occurs for the first time during pregnancy is called gestational diabetes. The blood sugar level is then elevated because of the hormonal change and can mostly be treated well with a dietary change. For some patients, however, an insulin therapy may become necessary.


    Regular blood sugar level tests by patients themselves are indispensable to treat diabetes mellitus, especially during a change in therapy and each time before administering insulin to reach a blood sugar level that is as balanced as possible. This enables patients to see for themselves, if their blood sugar level is within the recommended range, and it is the best way to avoid dangerous situations (metabolic imbalances) and secondary diseases in consequence.


    What we can do for you


    If there are known cases of diabetes in your family or you notice symptoms such as an excessive thirst, a frequent urge to pass water or fatigue for yourself you should undergo the necessary blood tests. Screenings for diabetes are an essential part of preventive medical checkups.


    In case you are diagnosed with diabetes mellitus you will immediately have many questions: what do I have to take into account in particular; what are the consequences for my life, my family, job and leisure time? To be able to understand the disease and how to deal with it patients need to be thoroughly informed, advised and trained. Specialists in internal medicine and diabetology are the ones to ask in such cases.


    The necessary knowledge and some training is what patients need to safely deal with diabetes in their everyday life. We want to support and accompany them. We provide our patients with all the necessary information and discuss appropriate treatments with them.


  • Underactive thyroid gland (hypothyroidism)

    Hypothyroidism is the most common functional disorder of the thyroid gland. It occurs in two different forms: as a fully manifested hypothyroidism, it affects about two out of a hundred people, and in its incomplete form, the so-called latent or subclinical hypothyroidism, it even affects seven to eight people out of a hundred. Women are about four times more often affected than men.


    How the thyroid gland works

    The thyroid gland is a small organ located in the neck, at about the area of the larynx or rather slightly below; in the case of women, it has a volume of up to 18 ml, in that of men of up to 25 ml. Controlled by the pituitary gland, the thyroid produces chemical messengers (so-called hormones) referred to as thyroxine and triiodothyronine. To maintain the hormone production without any disorders it is necessary to take up sufficient amounts of iodine from food. The thyroid hormones are released into the bloodstream which brings them to their so-called targeted organs at which they are meant to transmit certain effects. With this, the thyroid gland regulates a great amount of essential body functions and metabolic processes, such as the energy balance and body temperature, cardio-vascular and intestinal functions, the function of sebaceous and perspiratory glands, the mental efficiency and many more. For children, the thyroid gland plays a vital role for growth and development. The normal thyroid function is in disorder when the gland produces either too few (underactive thyroid or hypothyroidism) or too many (overactive thyroid or hyperthyroidism) of its hormones.


    Causes of hypothyroidism

    Hypothyroidism can be caused on the following three functional levels:

    • due to an underactivity of the thyroid itself (=primary hypothyroidism)

    • due to an underactivity of the pituitary gland that controls the thyroid (= secondary hypothyroidism) or

    • due to an underactivity of the so-called hypothalamus, i.e. the center of the brain that controls the

       pituitary gland (=tertiary hypothyroidism)


    Secondary and tertiary hypothyroidism are comparatively rare which is why we will focus on primary hypothyroidism. This form of thyroid underactivity is mostly caused by inflammatory processes, iodine deficiency, drug side effects and medical interventions, such as surgeries or radiotherapy.


    Symptoms of hypothyroidism

    The following are the most frequent and therefore most important signs of hypothyroidism:

    • fatigue, exhaustion

    • inexplicable weight gain

    • hair loss, dry skin

    • excessive feeling of cold, newly experienced sensitivity of feeling cold

    • newly experienced proneness to constipation


    What you can do for yourself

    A sufficient iodine uptake from food is most essential for a healthy thyroid gland and its normal functioning. This can, for instance, generally be achieved without any further effort by regularly using iodized table salt. Before deliberately increasing the iodine uptake, however, the thyroid should once be examined as an increased uptake can have a negative impact in cases of existing thyroid diseases.

    In addition patients should undergo a medical examination, in case they notice typical symptoms of hypothyroidism or a visible swelling of the gland.


    What we can do for you

    PKD am Städel disposes of a high-performance laboratory and a state-of-the-art ultrasound scanner of maximum efficiency. This enables our specialists in hormone disease diagnostics (endocrinologists) to thoroughly screen the thyroid gland and its hormonal balance, possibly detect abnormalities and their causes and inform our patients in full detail about necessary measures.


  • Osteoporosis

    About 30% of the population will suffer from osteoporosis when turning 75. With this insidious disease, the bones significantly lose stability. The WHO lists it as one of the ten most important diseases. As it often remains undetected, it is important to clarify potential cases with preventive examinations.


    Disease pattern

    Osteoporosis, also known as “bone decalcification” or “atrophy”, is a frequent disease. It often remains undetected, though, which may lead to severe consequences. The lower the content of calcium salts in the bones, the more frequent are fractures that might even result from rather harmless incidents. In the worst of all cases, this can lead to permanent immobilization and confinement to bed.

    Most vulnerable are the femurs, the femoral neck and the vertebral bodies, of the lumbar spine in particular.


    Who is at risk?

    Causes of osteoporosis can be genetic factors (e.g. osteoporosis of the mother), but also smoking, chronic inflammatory diseases, side effects of many medications (e.g. cortisone) and a generally reduced uptake of calcium (e.g. in cases of lactose intolerance).

    Recommendations for bone density scans are issued in reference to age, sex, and potential risk factors. The indications for bone density scans generally hold for women from the age of 70 and men from the age of 80.


    What can be done?

    DXA screenings are a worldwide established standard procedure working with a very low x-radiation and harmless for the patient. The examination takes about 10 minutes and there is no need for preparation for the patient. Results are available immediately after the screening and will be discussed. A follow-up appointment should be made if signs of disease indicate profound consequences. The endocrinology consulting hours (Prof. Dr. Jörg Bojunga) are an ideal offer for that purpose. The disease can be treated in different ways when detected early enough.


    What can we do for you?

    We have a DXA scan device of the latest generation at our disposal (Hologic Explorer). Either your family doctor can refer you to us for an examination or you directly make an appointment with us.


    What about the costs?

    A DXA screening costs roughly € 70 which will only be covered by statutory health insurance if a fracture due to osteoporosis has already occurred or osteoporosis has already been identified. In the case of private insurance patients, the screening cost will always be reimbursed.


    This newsletter does not claim to be exhaustive with regard to the information on the topic. It does not replace the guidelines and is only meant as an information tool issued by the practice.

  • Vitamin D

    Vitamin D is considered the basic hormone of life – it is produced in the skin through insolation or gained from food. It takes part in almost every important process in the human body; it causes the cell development and reproduction, is part of the immune reaction and contributes to the control of other hormonal systems. Vitamin D deficiency can therefore be a risk factor for several diseases, such as tuberculosis, cancer, osteoporosis (atrophy), disorders of the cardiovascular system, the nerves and muscles. Roughly 60% of the German population is suffering from vitamin D deficiency. It is advisable to have your vitamin and hormone levels checked to be able to react in the case of potential hazards.


    Vitamin D – the biological background

    Vitamins are vital substances that the human body cannot produce on its own. They therefore need to be taken up from food. This, actually, makes vitamin D not really a vitamin as there are preliminary components of it already in the body.


    80% of the needed amount is produced from these components in the skin through insolation (UV light). The remaining 20% must be taken up from food (mainly fish). The actual agent calcitriol (1,25(OH)2D3) is synthesized in another stage in the kidneys. This “activated vitamin D” can impact on several functions within the body, such as our immune system, when binding to the vitamin D receptor. It facilitates fast immune reactions and an efficient protection against autoimmune diseases.


    Calcitriol also controls the calcium level of the blood. Vitamin D deficiency can lead to a reduction of the calcium concentration. Kidney stones or decalcification of the bones (osteoporosis) are possible consequences.


    An important indicator for calcium deficiency is the parathyroid hormone level of the blood. This hormone is responsible for an increased calcium production within the blood. As a counter-reaction, a reduction in the calcium level will increase the production of the parathyroid hormone. If a test reveals an increased concentration, this might therefore be an indicator for calcium deficiency. Determining the parathyroid hormone level is part of measuring the level of vitamin D.


    Vitamin D – the social background in brief

    Vitamin D deficiency is quite a modern phenomenon; to be precise, it is a consequence of the industrialization of the 19th century.

    Large parts of the population fell into poverty; malnutrition, life in tenements and no access to fresh air increased, causing disorders of the vitamin D levels. Tuberculosis and rickets (a disorder of the bone growth of children) occurred increasingly. The success of sun cures, cod-liver oil and a healthy diet could only be proved a few years ago – these measures guaranteed an outstanding supply with vitamin D and strengthened the immune system.


    Even if our living conditions have improved substantially, roughly 60% of the German population is affected by vitamin D deficiency. This puts us far above the figures of other countries: in Norway and Japan, for instance, a high fish consumption supplies sufficient vitamin D, and in the US, certain food products are enriched with vitamin D.


    Who is at risk and what are the causes of vitamin D deficiency?

    The two main causes of vitamin D deficiency are an insufficient uptake of vitamin D from food and too little insolation. The latter is additionally caused by people increasingly working indoors, the geographic location (less sun in northern regions), clothing habits and the skin color (dark-skinned people produce only about a tenth of vitamin D under the same amount of insolation). A higher age and weight are also risk factors. Physical conditions that disturb the vitamin D synthesis or the uptake from food can also cause a low vitamin D level.


    What can you do yourself?

    With lots of fresh air and a healthy diet rich in vitamin D (especially with oily fish, mushrooms and dairy products) you can maintain a balanced vitamin D level. The recommended daily uptake for adolescents and adults is 10-20µg (400 IU) a day. It is, however, not easy to get enough vitamin D from food in Germany, as the fish consumption is rather low and supplementation of food products is illegal. It is therefore advisable to have your vitamin D level checked to be able to react fast and efficiently in the event of a potential risk (e.g. by prescriptions of vitamin D supplements).


    What can we do for you?

    We have a modern laboratory at our disposal to determine several parameters. In addition to vitamin D and parathyroid hormone levels, we can also provide you with hormone profile tests, cancer examinations and basic check ups. Please contact us for any questions if interested.

  • Colonoscopy / Preventive colonoscopy

    What does „preventive“ actually mean?

    To be precise, „preventive” means „in good time”; identifying issues early enough, removing their causes early enough before any lethal disease enters a final stage and cannot be treated anymore.


    This refers to colon cancer, the colorectal carcinoma. There are 70,000 new cases each year in Germany alone! This is a frightening figure and these cases could be avoided if only these patients (or most of them) got a preventive check.


    Malignant tumors in other organs develop spontaneously and immediately are malignant. Most colorectal carcinomas, on the opposite, develop from a benign growth, a polyp. These polyps (either pedunculated, like a cherry with a stalk, or sessile, like a button sewed onto the tissue) keep growing over years without causing any symptoms. Sometimes undetected light bleedings can occur (which is why stool is tested for blood). At some point, however, part of the polyp cells are converted into carcinoma cells and the situation will change quickly from then; the malignant cells are reproduced, penetrate the colon wall, link up with blood and lymph vessels and can spread into and destroy other organs (the liver, in particular).


    This spreading is called metastasis. At this stage, there is no possibility to cure the patient anymore, neither by chemotherapy or surgery, nor by any other modern procedure.


    What can colonoscopy do?

    When well prepared and done by an experienced physician, colonoscopy can examine all parts of the colon up to the junction to the small intestine in very detail. The smallest polyps of only a few millimeters in size can be detected and usually removed during the same examination – just like larger ones, too – giving the preventive screening particular importance.


    Roughly 20-30% of the initially benign growths would later become malignant carcinomas (i.e. not every polyp turns into a carcinoma, but almost every carcinoma used to be a polyp).


    Who should be screened?

    Statutory insurance patients are advised to get a preventive colonoscopy from the age of 55. The German Association of Gastroenterology, Digestive tract and Metabolism Diseases (DGVS), though, has good reasons to recommend getting an examination already from the age of 50.


    If a colon tumor occurred within the family, the examination must be done earlier. This also applies, of course, if other symptoms are found, such as blood in the stool; also, in cases of unclarified abdominal pains or unclarified loss of weight or energy.


    How is a colonoscopy done?

    You will be briefed with all necessary information about the preparatory emptying of the bowels and the screening procedures beforehand.


    The emptying of the bowels should start no later than 8 hours before the examination. Only if correctly prepared, a thorough examination is possible. An anesthesia specialist will take care of you during the procedure which takes about 20 to 45 minutes. Afterwards, you will stay for about 1 hour in the recovery room. You will need company to take you home as you won’t be allowed to drive due to the sedation. Even if using public transport, it is advisable to have someone to accompany you home.


    You will immediately get a findings report with images documenting your case. If tissue samples are sent to a pathology laboratory, you will receive a second report a week later stating all further procedures. The physician referring you to us or your family doctor will get a copy of the results, respectively.


    What can we do for you?

    The examination is done at our gastroenterology/endoscopy department at Praxisklinik für Diagnostik (PKD am Städel) by our specialists with outstanding expertise (experienced gastroenterologists from clinical senior positions and senior physicians from Universitätsklinik Frankfurt).


    Appointments for briefings and examinations can directly be made by contacting us.

  • Sleeping disorders / snoring

    Waking up relaxed after a good night’s sleep cannot be taken for granted by everyone! Our sleep is highly complex. It can be divided into different stages and shall relieve our mind and body from stress. Our brain controls every single moment of our sleep. Sleep disorders may have an impact on other important functions or organs such as, e.g., the cardiovascular system, our metabolism and the brain itself. About 20% of the German population is suffering from malfunctions in the observation and control of our sleep, which means getting too much or too little of it.


    The most common sleeping disorders are:

    • insomnia (difficulties to fall asleep or sleep through the night, early waking up, non-relaxing sleep)
    • sleep apnoea (breathing interruptions during the night, snoring, fatigue during the day)
    • restless legs syndrome (an urge to move the legs, especially in repose)
    • narcolepsy (strong day fatigue in uncommon situations, sudden loss of muscle tension)


    Who should be screened at a sleep laboratory?

    Symptomatic sleeping disorders can have many causes: pain or an increased urgency, cardiovascular and metabolic diseases such as diabetes mellitus, thyroid gland diseases as well as psychological disorders. This means that, first of all, the underlying disease needs to be identified and treated as necessary.

    Patients that cannot get relaxing sleep even if constantly trying or that are suffering from one of the following symptoms or diseases should be examined at a sleep laboratory:

    • persisting problems with falling asleep or sleeping through the night
    • fatigue and the urge to fall asleep during the day, brief dozing off during monotone activities such as reading or watching TV, microsleep while driving
    • a racing heart, shortness of breath, increased urination or increased sweating during the night
    • strong and/or irregular snoring with or without interruptions of breathing
    • patients with cardiovascular diseases
    • patients with an occurred stroke or heart infarction
    • diabetics
    • patients suffering from Parkinson’s disease


    What can we do for you?

    If you notice one or several of these symptoms in yourself, you can contact us directly or ask your family doctor, an ENT specialist or a pneumologist for referral to us. We will then first screen you in an ambulatory sleep examination at home (“ambulatory PG” or “cardiorespiratory polygraphy”). If this proofs the initial suspect or the degree of the disorder, you will be recommended a screening at the sleep laboratory. Based on the results of this much more detailed measuring, you and the physician referring you to us will get a precise diagnose with respective therapy recommendations.

  • Arteriosclerosis / carotis artery

    Calcification or even sclerosis up to an arterial occlusion will remain undetected (without symptoms) until reaching a critical limit. With first symptoms appearing, they will have reached such an advanced stage that “invasive” measures, by means of catheterization or surgery, have to be taken.


    The following are some important examples: angina pectoris in the case of sclerosis of the coronary arteries, intermittent claudication due to diseases of the pelvic and leg arteries, TIA (neurologic dysfunctions remaining for hours that will cease again, but are always alarm signals for strokes with lasting damages) due to arteriosclerosis of the carotis artery.


    It is especially about identifying low-degree changes in the arteries in good time to then be able to “prevent” the disease from worsening. That can be through medication, for instance.


    This is about the carotis artery.

    The artery lies close to the skin surface and can easily be reached with non-invasive diagnostic measures. Changes of the artery are considered to be indicators of the patient’s vascular risk.


    What does vascular risk mean?

    Many patients believe arteriosclerosis to be a passive process in which the calcification starts with sediments gathering on the inner side of the artery, comparable to sedimentation in water pipes. This is not true, though. It is much more of an active, inflammatory process starting from the several layers of the artery wall that leads to a swelling (like wood in water). The calcification is the end product of such inflammatory processes. Especially vascular risks facilitate them within the artery wall. These risks might be genetic (“familiar disposition”) and therefore unavoidable. They are, however, also caused by our lifestyle (smoking, lack of movement, high fat diet); even other diseases can be massive vascular risks having a strong impact (e.g. high blood pressure, diabetes, dyslipidemia).


    How can the carotis artery be examined?

    The artery can easily be examined in almost any case with modern ultrasound devices and respective high-resolution transducers. The carotis Doppler sonography has no side effects or radiation exposure. It does not need any contrast agent and takes roughly 15-20 minutes. The transducer is placed over the artery through a sound-conducting gel. The thickness of the artery wall is measured on the left and the right side (as precise as measuring a tenth of a millimeter!) as well as the blood flow velocity. The results will help judge the quality of the arterial system (also in other areas of the body). If any stenosis (plaques) is detected, the physician can immediately assess the stenosis degree and if the risk of a stroke is imminent.


    Who should be examined?

    Patients with acute symptoms (unclarified dizziness, short neurologic dysfunctions or the like) as well as patients with known risk factors should be examined. What needs to be kept in mind in particular is that with several risk factors identified, the vascular risk increases disproportionally. This means that the risk of a vascular disease is higher than one would probably think. Let us give you an example: a 45-year old man and occasional smoker is stressed in his job and develops an increased blood pressure. He has no time for sports and tells about his father who had to get a first cardiac catheterization at the age of 59. There are 4 risk factors already having an impact although the patient only notices the high blood pressure.


    What can we do for you?

    Carotis Doppler sonography is done with a high-end ultrasound device. If substantial arterial changes of the carotis are found, we will also plan screenings of other vessels with you. If the arteries are already dangerously sclerotic (a significantly high stenosis degree), the necessary emergency measures will be taken in cooperation with Universitätsklinik Frankfurt or other clinics specialized in vascular surgery.


  • Ultrasound screenings

    Today, almost every examination in internal medicine uses the technical possibilities of ultrasound screenings. These are meant to provide some general information and answer frequently asked questions without focusing on specific symptoms or disease patterns.


    What actually is ultrasound?

    A device with a crystal surface applied directly on the body is used to transmit onto, conduct through and let reflect its very fast movements from the organs lying underneath. You may compare this to a cell phone lying on a table with its vibrations still noticeable at the other end of the table. For medical purposes, the frequency (number of oscillations per second) of the vibration used is a thousand times higher than the one of audible sound; it is therefore called ultrasound.


    The ultrasound sender is also the receiver of the reflected sound waves. This part of the device is called a “transducer”. It is connected to a computer with specialized processors that measure the distance between the sender and the reflecting structure within the short time between the sending of the ultrasound impulse and the reception of the reflected signal. This marks a pixel on the screen. By placing many vibrating crystals next to each other and sending many impulses per second, the large number of marked pixels will then create a picture matching a cross section image of the corresponding body area. This is comparable to a cross section of the sea that a fishing boat will receive when looking for a shoal of fish with its sonar and that will display on its screen as sound reflecting points.


    Are ultrasound screenings harmful?

    So far, there has been no evidence of any harmfulness. The examinations can be repeated as often as necessary, which makes for the main difference of this technology compared with radiation-based screenings such as x-rays or computer tomographies (CT). Their unavoidable radiation will always cause cell damages.


    Several new ultrasound procedures have been developed to deal with particular issues (e.g. color duplex/contrast sonography). These screenings leave a larger amount of “sound energy” in the examined tissue and thereby cause a slight warming of the area; hence, it is recommended to keep examinations brief in the case of pregnant women and small children.


    What is possible with ultrasound screenings and what is not??

    A cross section can be examined of any organ or structure having a certain volume or being filled with liquid. The surface of an organ or of a certain part of it is not displayable, though.


    Compare it to an apple; if you cut it in half, the section will show the core, rotten bits in the flesh, possibly a worm hole, etc. You won’t be able to see, however, if the skin is red or green, dirty or moldy. In the same manner, a section image of the liver can show suspicious tissue (e.g. a tumor); a section image of the gall bladder filled with bile can display stones. From a cross section of a filled stomach, however, one cannot say if there is an inflammation in the mucous membrane of the displayed stomach wall; the surface would have to be checked to do so (e.g. during a gastroscopy).


    The characteristics of moving liquids can well be displayed, e.g. the blood flow. Together with a picture of a thickened artery wall, the stenosis degree can exactly be assessed with a given accelerated blood flow. Other important characteristics of the blood cannot be identified by ultrasound. The screening cannot reveal anything about a potential anemia or the blood oxygen level, for instance.


    What can we do for you?

    The quality of an ultrasound screening heavily depends on the experience and the expertise of the physician and on the technical conditions, i.e. the ultrasound devices and the transducers used in the examination.


    All physicians at PKD am Städel (Praxisklinik für Diagnostik) are long experienced with ambulatory and clinical ultrasound diagnostics. Some of them are members of DEGUM (Deutsche Gesellschaft für Ultraschall in der Medizin) and are certified specialists of its high-standard categories “DEGUM 2” and “DEGUM 3”.


    They work with state-of-the-art sonography devices (Acuson Sequoia 512/ X700/S2000 by Siemens), using the latest technology (color duplex, contrast sonography, 3D sonography, elastography).


    Here you will find a more detailed description of the different examinations.

  • Coughing

    Coughing, first of all is a protective reflex if the gas exchange in the pulmonary alveoli is blocked – by secretion or phlegm produced in the lungs – or if there is any foreign matter in the airways – for example, after swallowing something the wrong way.


    An inflamed bronchus will also cause a couching reflex, just like an acute bronchitis would frequently do. This mostly viral disease will often start with a painful and initially dry cough a few days after a cold; it will usually last for 4-7 days and be self-limiting. If the patient, however, notices green-yellow phlegm when coughing up in addition to symptoms such as a persisting fever for 7 days, the patient should see a physician to clarify a potential bacterial bronchitis that needs further treatment.


    Acute coughing

    Medicine differentiates between acute and chronic cough. The most frequent causes of acute cough are infections (see above) or the acute worsening (exacerbation) of an existing lung disease (e.g. asthma, allergies). In rare cases, acute cough can be an indicator for other, partly life-threatening diseases.


    Chronic coughing

    The major cause of chronic cough (>8 weeks) is smoking, followed by chronic bronchitis (COPD), but many other diseases, e.g. gastroesophageal reflux or cardiac insufficiency as well as medication, e.g. ACE inhibitors or beta blockers, or environmental influences can be responsible for the symptoms, too. In cases of chronic cough, one should therefore always see a doctor to get a diagnosis and start an appropriate therapy.


    What can we do for you?

    If you are suffering from acute or chronic cough with or without phlegm or any additional symptoms as described before, we can run further tests and diagnostics and start a therapy. To do so, we can check general internal examination parameters as well as the functions of the lungs, e.g. by spirometry, which can be done quickly, by body plethysmography and by spiroergometry, that will yield lots of relevant data to help find a diagnosis.

  • Elastography

    Elastography is a special kind of ultrasound scan that measures the firmness or elasticity of an organ or of a structure within an organ.


    Modern ultrasound technology already grants a high „spatial resolution” in section view (or “temporal resolution” in the case of moving structures, e.g. the cardiac valves) allowing us to display and quantify the blood circulation (“color duplex”). Elastography now adds the possibility of measuring another important property of the tissue without surgery or punctures.


    Internal medicine particularly uses this procedure to examine the thyroid gland and the liver.


    When does elastography make sense?

    Sonography scans of the thyroid gland often reveal lumps. These can be malignant in rare cases; with views to the large number of newly detected lumps, not all of the findings can be clarified by a puncture or even surgery. This makes sonography scans that important to differentiate between malignant and benign ones.


    Elastography now screens another significant property of the lumps: their firmness; the harder, more solid or more inelastic a lump is, the more likely it is that it consists of malignant cells (this especially applies in cases in which already known properties, such as a poor echo, irregular borders, an oval shape, an increased circulation, calcifications, are additionally detected).

    Elastography of the liver particularly focuses on diffuse changes of the liver tissue: the harder or more solid the tissue is, the more connective tissue has developed in the liver and the more likely it is that a liver cirrhosis will develop; this means a loss of functioning liver cells in favor of connective tissue cells that are unable to function.


    The earlier this process is detected, the earlier steps can be taken to counter it. The following is a frequent case: if sonography reveals suspicious tissue of a potential fatty liver (that can develop without the effect of alcohol, too), the scan will already show inflammatory processes (“hepatitis”), due to slightly or non-increased laboratory parameters (results from liver function tests), that will consequently cause changes in the liver tissue as described.


    Further damage can either be avoided or, at least, considerably slowed down if these changes are detected early and counter measures are taken (e.g. dietary recommendations, potential medication, scheduling the monitoring of the disease development, etc.). This particularly applies to cases of patients with a chronic viral hepatitis or a rare liver inflammation due to a disorder of the immune system.


    What can we do for you?

    Examinations with our state-of-the-art sonography devices are completely painless and there is no need for any preparation. A scan takes roughly 10-15 minutes. It is recommendable to get a liver scan with an empty stomach or 2-3 hours after the last meal.

  • Fructose intolerance (fructose malabsorption)

    In many cases, the causes of gastro-intestinal disorders remain concealed. If the patient experiences troubles with the bowels especially after eating fruit, it could be due to an intolerance of fructose (fruit sugar). This type of metabolic disturbance is also referred to as fructose malabsorption and it has gained importance as a cause of intestinal disorders over the years.



    Malabsorption means a disorder in the uptake and transport of nutrients from the inside of the bowel into the blood and lymph vessels. Fructose malabsorption therefore refers to a limited uptake of fructose in the small intestine and – consequently - the blood circulation, caused by a dysfunction of the GLUT5 protein responsible for fructose transport. If this transport mechanism is disturbed, the fructose absorption from food by the mucous membrane of the small intestine cannot happen at all or only in a limited way. It ends up in the colon where it is decomposed by bacteria resulting in fatty acids and intestinal gas causing the typical troubles such as flatulence, diarrhea or constipation as well as abdominal pain or cramps, nausea and vomiting. This defect can occur temporarily or permanently. At the same time, it is important to understand that it is not an allergic reaction.


    What is affecting the fructose transport mechanism?

    Sorbit(-ol), a sugar alcohol, limits the transportation of fructose. Some types of fruit contain sorbit(-ol), and it is also used by the food industry as a sugar substitute (E420) in sugar-free or low-sugar sweets.


    The following may contain sorbit(-ol):

    • low-calorie candy and chewing gum

    • fruit such as apples, pears, plums

    • dried fruit such as prunes, apricots, dates

    • fruit jams and jellies

    • sweets

    • dietary products such as low-sugar jams, chocolate

    • beer, wine


    The simultaneous consumption of glucose (dextrose) enhances the fructose uptake and can therefore have a positive impact on the system. Glucose can easily be purchased and used as a sweetener. The positive effect of glucose also explains why usually sucrose (household, cane or beet sugar) is well-tolerated in low quantities. When split, sucrose will break down into equal amounts of free fructose and free glucose. This leads to a good fructose uptake as glucose stimulates the remaining fructose transport activity.


    Not to be confused with (hereditary) fructose intolerance!

    One basically needs to understand the difference between fructose malabsorption and hereditary fructose intolerance (HFI), the latter occurring much more seldom. HFI is caused by a congenital enzyme deficiency that already shows in early infancy when feeding the baby with fruit, vegetables or honey, for instance. In such cases, the body completely absorbs the fructose from food products, but then is unable to metabolize it. This leads to fructose sedimentation in the intestinal wall, kidneys and liver and can lead to hypoglycemia (low blood sugar levels), liver and renal dysfunctions.


    What can you do if you suspect suffering from fructose malabsorption?

    Already with reducing your consumption of sorbit(-ol) and food products containing fructose you can achieve quite something for yourself. It is not necessary to completely avoid fructose. You can enhance the fructose uptake by consuming glucose (dextrose) at the same time, which is also why there is no need to avoid household sugar (sucrose). Try and avoid diabetic food, eat fructose-containing food products slowly and when drinking fruit juice, try not to drink up at once.


    What can we do for you?

    If you think you may suffer from fructose malabsorption, you should get in contact with an internal medicine specialist (gastroenterologist). Making a diagnosis is a complex issue as symptoms are not always clear. There may as well be other causes of gastrointestinal disorders. We will first do some basic tests (blood count, inflammatory parameters, ultrasound diagnostics) to try and exclude other potential causes of the symptoms. If these substantiate an initially suspected fructose malabsorption, a breath test is advisable measuring the hydrogen concentration in the exhaled air. The patient then has to drink up a fructose solution and afterwards regularly exhale into a test device. The unabsorbed sugar will be fermented by colon bacteria, leaving hydrogen among other components. Through the intestinal wall, this gas will get into the blood and, with it, into the lungs from where it is exhaled and can be measured. If this confirms a fructose malabsorption, a change in the patient’s nutrition habits will become necessary. We then recommend seeing a nutritionist to jointly set up a nutrition plan in accordance with your individual needs.


  • Lactose intolerance

    Roughly one in five Germans is suffering from lactose intolerance and cannot take any milk sugar naturally contained in milk and dairy products. This even applies to more than 80% of the world population. The affected ones are either lacking or have an insufficient level of the enzyme responsible for decomposing milk sugar in the bowels. The consequences of milk sugar consumption are then often very unpleasant and range from nausea and vomiting to fatigue, diarrhea and abdominal cramps.


    What are the factors responsible for lactose intolerance?

    Lactose is Latin for milk sugar. Lactose intolerance is the organism’s inability to correctly digest milk sugar. It is usually broken down by an enzyme (lactase) into two monosaccharides – galactose and glucose (dextrose) – inside the small intestine. A protein then transports these monosaccharides into the body through the mucous membrane of the bowels. If the enzyme is lacking or only insufficiently available, milk sugar cannot be split, or at least not completely, and reaches the colon where bacteria process the milk sugar and form gases leading to the typical symptoms of lactose intolerance.


    What forms of lactose intolerance are there?

    Congenital lactose intolerance

    This is a genetically determined form of complete lactose intolerance: it is caused by a genetic defect strongly limiting or totally inhibiting the formation of lactase. It is a very rare autosomal recessive disorder that already affects newborn children and cannot be cured.


    Primary lactose intolerance

    This is the most common form of lactose intolerance. It is also genetically determined and can increasingly be found in regions with a high insolation. Under this condition, the ability to digest lactose diminishes with age. 70% of all Europeans are affected already at the age of 60. The reason for the reduced enzyme production in adults is an autosomal recessive gene mutation that cannot be cured.


    Secondary lactose intolerance

    This form of lactose intolerance is not genetically determined; it is a disorder of the mucous membrane of the bowels. As mentioned before, the lactase enzyme is released through the mucous membrane of the small intestine. If this layer of the bowel is damaged by other diseases or medication (such as a harmful bacterial colonization in the gut flora, taking antibiotics during a longer period of time, forms of intolerance like fructose malabsorption, Crohn’s disease, coeliac disease, alcoholism), it is no longer able to release lactase. Usually, secondary lactose intolerance is a temporary condition. It is curable and passes with eliminating the cause of the bowel damage.


    Which symptoms can be detected and how do they develop?

    If the enzyme does not split the lactose, it immediately reaches the colon where bacteria comes into play. Lactic acid, short-chain fatty acids (acetic acid, butyric acid, …) and gases such as hydrogen, carbon dioxide or methane figure among the waste products of the bacterial decomposition. As these substances are formed in larger amounts, they can lead to abdominal pain, flatulence, nausea and diarrhea.


    Not to be confused with milk allergy!

    It is essential to differentiate between lactose intolerance and milk allergies (casein, lactalbumin, cow’s milk allergy). The latter refer to allergic reactions to certain ingredients of milk. Even the smallest amounts (traces) can cause symptoms. Lactose intolerance differs from allergies in this respect as small amounts are usually harmless.


    What can you do to identify a potential lactose intolerance?

    If you suspect suffering from lactose intolerance, we recommend writing a symptoms journal. Write down when and what you are consuming, and when and which symptoms appear consequently. This will make it easier for the physician to narrow down the symptoms pattern.


    What can we do for you?

    If you think you may suffer from lactose intolerance, you should get in contact with an internal medicine specialist (gastroenterologist). Making a diagnosis in cases of lactose intolerance is a complex issue as symptoms are not always clear. There may as well be other causes of gastrointestinal disorders. We will first do some basic tests (blood count, inflammatory parameters, ultrasound diagnostics) to try and exclude other potential causes of the symptoms. If these substantiate an initially suspected lactose intolerance, a breath test is advisable measuring the hydrogen concentration in the exhaled air after the patient had to drink up a lactose solution. In case of lactose intolerance, this concentration is usually elevated. If this confirms lactose intolerance, a change in the patient’s nutrition habits will become necessary. We then recommend seeing a nutritionist to jointly set up a nutrition plan in accordance with your individual needs.