Marine-Lenhart Syndrome – Causes, Symptoms & Treatment


Marine-Lenhart syndrome is a relatively rare disease. Graves’ disease or another autoimmune thyroid disease associated with an overactive thyroid occurs here along with warm thyroid nodules. A differential diagnosis is difficult, the symptoms of the syndrome largely correspond to those of Graves’ disease and an overactive thyroid.

What is Marine-Lenhart Syndrome?

Marine-Lenhart syndrome is a variant of Graves ‘ disease in which coexistent autonomic thyroid nodules are present. It is also commonly referred to as Graves’ disease with coexistent multinodular goiter or nodular Graves’ disease because it is considered by many to be a subtype of Graves’ disease.

The syndrome is rare, with a reported prevalence ranging from 1-4.1 percent in patients with Graves’ disease. The autoimmune disease with stimulating autoantibody occurs at the TSH receptor in a coexisting nodular gland. The syndrome was first described in 1911 by American surgeons David Marine and Carl H. Lenhart. In studying goiter, they found eight cases in which goiter was associated with thyroid nodules.


Marine-Lenhart Syndrome is an autoimmune disease of the thyroid gland. Graves’ disease grafts onto an already existing goiter. On the one hand, this is caused by a genetic defect in the immune system . On the other hand, external influences such as smoking, viral infections or psychosocial stress intensify the disease.The interaction of several factors finally leads to the fact that the thyroid’s self-tolerance towards antigens breaks down. This results in an autoimmune disease. The autoantibodies formed bind to the TSH receptor. Through their intrinsic activity, they stimulate the follicular epithelial cells of the thyroid gland.

This leads to increased iodine intake, increased production and release of thyroid hormones and ultimately to hyperthyroidism . In Graves’ disease, the TSH receptors are damaged and destroyed, resulting in SD hormones being formed uncontrollably. Marine-Lenhart syndrome results from the association of Basedow’s disease with focal autonomy. These are delimited nodes that produce SD hormones uncontrollably and independently.

Symptoms, Ailments & Signs

The possible symptoms include all complaints that can also occur with hyperthyroidism. These range from the typical goiter to insomnia , fatigue , irritability and tremors . High blood pressure , cardiac fibrillation or unwanted weight loss can also be the consequences.

At the same time, the mobilization of glycogen and fat reserves leads to glucose tolerance and possibly even hyperglycemia . Furthermore, the syndrome is also noticeable through the symptoms of Graves’ disease. These include, but are not limited to, protruding eyeballs, myxedema , muscle weakness , osteoporosis , and menstrual cycle disorders that can lead to temporary infertility.

Heat intolerance, sweating and increased stool frequency can also be signs. When the knots press on the trachea, it causes difficulty in swallowing and a feeling of tightness in the throat.

Diagnosis & course of disease

When the disease is diagnosed, differential diagnostic challenges arise. During primary hyperthyroidism, the nodules initially appear scintigraphically cold. After therapy, however, they turn out to be normally storing or warm areas. A blood sample is used for the diagnosis . Here, the antibodies TPO and TG are searched for.

These are specific antibodies that are used to detect Graves’ disease and diseases of the thyroid gland. An ultrasound scan will then look for both nodules and thyroid inflammation. Features that indicate inflammation of the thyroid are a diffusely enlarged gland, hypoechoic glandular tissue, and significantly increased blood flow, known as the “thyroid inferno”.

Even if the abnormalities in the ultrasound scan are usually indistinguishable from the symptoms of Hashimoto’s thyroiditis, the clinical picture and the blood tests make a diagnosis easy. SD scintigraphy provides additional clarity.


Marine-Lenhart syndrome causes many different symptoms that significantly reduce the quality of life of those affected. In most cases, patients suffer from severe fatigue caused by insomnia. It is not uncommon for those affected to be irritable and lend aggressively. High blood pressure also occurs, so that the patients can also suffer a heart attack, which in the worst case can be fatal.It is not uncommon for weight loss and muscle weakness to occur. The patient’s everyday life is severely restricted by the Marine-Lenhart syndrome and there are outbreaks of sweating or difficulty swallowing. Difficulty swallowing can also lead to restricted intake of liquids and food, leading to dehydration or various nutritional deficiencies.

In most cases, no surgery is necessary for Marine-Lenhart syndrome and treatment can be carried out with the help of drugs and radioactive preparations. There are no further complications or symptoms, and the patient’s life expectancy is not reduced if treatment is given early. However , those affected are usually dependent on hormones throughout their lives .

When should you go to the doctor?

Sleep disorders, tiredness or fatigue are signs of an existing health impairment. If the condition persists or increases in intensity, a doctor is needed. Feeling restless, irritable, or shaking is cause for concern. A doctor is needed so that alleviation of the symptoms can be initiated by medical care for the person concerned. Heart rhythm disorders, high blood pressure, internal heat or heartbeat interruptions must be examined and clarified by a doctor as soon as possible. If there is a sudden and unwanted decrease in body weight, this is a sign of an existing irregularity.

Symptoms of the act of swallowing, a refusal to eat and visual changes in the face should be presented to a doctor. If you break out in a sweat or lose your usual physical performance, you should consult a doctor. If everyday obligations can no longer be met, participation in social activities decreases, or other behavioral problems arise, the person concerned needs help and support.

Difficulty breathing or a feeling of tightness in the throat should be evaluated by a doctor. Muscle weakness and, in sexually mature women, an irregular menstrual cycle are further signs of a health problem. There is a need for action to enable a diagnosis to be made.

Treatment & Therapy

Initial therapy usually consists of taking antithyroid drugs . However, this treatment should only be carried out for a limited time, until eutheryosis, i.e. the normal function of the thyroid gland, is achieved. SD hormone-inhibiting drugs help about half of those affected to heal. Once thyroid hormone levels are under control, other treatment options can be considered.

If the malignancy of the finding could be ruled out, radioiodine therapy can be used. The radioactive iodine isotope is used in this nuclear medicine procedure. Predominantly a beta emitter, it has a half-life of eight days. In the human body, it is only found in cells of the thyroid gland.

The beta rays damage the DNA around the thyroid cells, eliminating the affected cells. Since patients affected by Marine-Lenhart syndrome have often developed resistance to radioiodine, a higher dosage is required. As a result, many sufferers have been successfully treated in the past.

In the past, surgery was considered the only effective therapy. Even today, if there are several knots, their surgical removal can lead to success. Removal of the entire thyroid is also conceivable. However, in this case, patients will have to take hormones for the rest of their lives.

Outlook & Forecast

Marine-Lenhart syndrome has an unfavorable prognosis. The disease is due to a genetic defect that has not yet been cured. Modification of human genetics is not permitted for legal reasons. Physicians and medical professionals focus their attention on the use of symptomatic approaches in treatment.

The individually occurring complaints are treated in the best possible way with different therapies. Hormonal preparations mean that about half of the patients are largely symptom-free. However, if the drug is discontinued, the symptoms can be expected to return. Therefore, lifelong drug treatment must take place in order to stabilize the patient’s quality of life.

If the course of the disease is unfavorable, there will be subsequent disorders. The cardiovascular system is exposed to enormous stress. In some patients, premature death due to heart failure is therefore documented. In addition, malignant disease developments can occur. Here, too, those affected are threatened with a reduction in their average lifespan.

In addition to the administration of hormones, a stable psyche is of particular importance as helpful and supportive. Since the affected person has to undergo long-term therapy, self-help measures and the avoidance of harmful substances are important. With a healthy and stable mental state, improvements in the overall situation can often be observed.


Since Marine-Lenhart syndrome is related to Graves’ disease, the same risk factors apply to both diseases. Psychosocial stress should be avoided as much as possible. Relaxation exercises can help to defuse stressful situations. Smoking can also promote the development of the disease. In addition, viral diseases should be carefully treated and cured.


Marie-Lenhart syndrome can require lifelong follow-up care. This is independent of the respective treatment method. It is also necessary to prevent ocular discomfort due to endocrine orbitopathy, which is possible in about 50 percent of all patients. In addition, post-treatment requires a lot of effort and patience. The therapy strategies are designed for the medium to long term.

In the case of conservative drug therapy, the patient receives antithyroid drugs for one to two years. Depending on the initial situation, the risk of a recurrence is 30 to 90 percent. The follow-up examinations must take place every four to eight weeks. The safest and fastest treatment methods for Graves’ disease are radioiodine therapy and surgery.

However, following these procedures, it is necessary to take thyroid hormones for the rest of life. This is the only way to compensate for the resulting hypofunction of the thyroid gland, i.e. a lack of thyroid hormones. If regular check-ups are necessary at the beginning, these are then limited to one or two examinations a year.

Immediately after surgery on the thyroid gland, the patient receives thyroid hormones in a standard amount. How many hormones the patient ultimately needs is determined after the operation and individually adjusted accordingly. The target values ​​vary and are determined by the general practitioner or an endocrinologist.

You can do that yourself

Marine-Lenhart syndrome is primarily treated with medication. Patients can support the antithyroid therapy by taking it easy and informing the doctor if they have unusual symptoms. In general, it is advisable to keep a complaints diary in which any symptoms of the disease and side effects of the medication used are noted. This makes it easier for the doctor to optimally adjust the medication to the individual condition of the patient. Radioiodine therapy can also be supported by those affected by good cooperation with the doctor responsible.

If these measures are ineffective, an operation must be performed. After an operation, the diet must be changed to ensure a rapid healing process. Those affected should also avoid stimulants such as alcohol and caffeine and, if necessary, stop smoking .

At the same time, the individual symptoms must be treated. A walk in the fresh air often helps against breaking out in a sweat. Irritability and tremors can be counteracted with targeted relaxation measures. Stress and physical exertion should be avoided if possible until the symptoms of Marine-Lenhart syndrome have subsided. If there are cardiovascular problems or cycle disorders, other doctors may have to be consulted.

Website | + posts

Hello! I am Lisa Newlon, and I am a medical writer and researcher with over 10 years of experience in the healthcare industry. I have a Master’s degree in Medicine, and my deep understanding of medical terminology, practices, and procedures has made me a trusted source of information in the medical world.