What Is Adiposogenital Dystrophy?
Adiposogenital dystrophy is an endocrine disorder characterized by obesity and decreased production of sex hormones (hypogonadism). The condition is the result of damaged hypothalamus. Hypothalamus is a structure deep in the brain that is the body’s smart control coordinating center. It maintains homeostasis in the body directly (by influencing the autonomic nervous system) and indirectly (through hormones).
The hypothalamus can be damaged by:
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Infection - A few infections that have been known to cause damage to the hypothalamus are viral and bacterial meningitis (inflammation of the membranes in the brain), encephalitis (inflammation of the brain), meningoencephalitis (inflammation of the membranes and brain), arachnoiditis (inflammation of the arachnoid membrane), and toxoplasmosis (a parasitic infection), and syphilis (sexually transmitted bacterial infection).
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Functional Failure - A few conditions that cause hypothalamus dysfunction are brain tumors, nutritional deficiencies, brain aneurysms, genetic disorders, etc.
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Trauma - This can be a direct trauma or secondary from brain surgery. The resultant inflammation in both conditions has the potential to damage the hypothalamus.
The condition predominantly affects children and adolescent males and appears similar in inherited growth delay disorders. Physical examination, laboratory investigations, and imaging studies can diagnose it. Treatment primarily involves hormone replacement therapy to replace the reduced hormones.
Adiposogenital dystrophy is also known by different names. They are
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Frolich’s syndrome.
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Sexual infantilism.
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Babinski-Frohlich syndrome.
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Hypothalamic infantilism obesity.
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Dystrophia adiposogenitalis.
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Launois-Claret syndrome.
What Is the Pathogenesis of Adiposogenital Dystrophy?
The hypothalamus is a bilateral structure just below the thalamus. It connects the nervous system to the endocrine system through the pituitary. The hypothalamus is composed of different nuclei.
The hypothalamic nuclei are distinct masses of gray matter in the central nervous system that synthesize different hormones, like gonadotropin-releasing hormone (GnRH), thyrotropin-releasing hormone (TRH), growth hormone-releasing hormone (GHRH), etc., in response to physiological changes. The functions of the hypothalamus are-
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Food intake.
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Temperature.
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Thirst (fluid regulation).
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Endocrine.
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Reproduction.
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Sleep and wakefulness.
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Emotion.
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Stress.
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Circadian rhythm.
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Visceral function.
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Somatic.
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Reward and punishment.
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Autonomic system (regulates involuntary physiological processes like a heartbeat, sexual arousal, etc.).
In the hypothalamus, these systems and the limbic, neocortical, and spinal influences are integrated with one another. Together, they maintain homeostasis and participate in the substructure of emotion and affective behavior.
Intrauterine infections (due to syphilis), brain tumors, birth injuries, and other hypothalamus-damaging abnormalities will cause damage to the nuclei of the hypothalamus leading to reduced or absent production of hormones like GnRH, GHRH, TRH, etc., which ultimately lead to developmental symptoms specific to adiposogenital dystrophy.
What Are the Symptoms of Adiposogenital Dystrophy?
The various signs and symptoms observed in Froelich syndrome are-
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Deficiency in the ligament-joint system.
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Excess fat is stored mostly in the face, chest, thighs, and abdomen.
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Dry and thin skin.
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Abnormalities in the gastrointestinal tract.
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Difficulty in the outflow of bile (digestive juice).
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Constipation.
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Myocardial infarction (stroke) due to degenerative cardiovascular changes in the cardiac muscle.
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Impaired intellectual development.
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Eunuchoid (lack of sexual characteristics) type stature.
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Disrupted development of the skeleton.
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Poor secondary sexual characteristics.
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Delayed puberty.
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Cryptorchidism (failure in the descendants of testicles).
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Hypotrophy (reduced development) of the testes and penis in males and vulva in females.
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Gynecomastia (increased breast size) in males.
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Hypothermia (reduced body temperature).
Individuals with adiposogenital dystrophy may also suffer from the infundibulo-tuberal syndrome, a combination of endocrine, metabolic, and behavioral disturbances. The classical signs of the infundibulo-tuberal syndrome in patients with adiposogenital dystrophy are as follows:
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Intellectual disability.
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Diabetes.
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Poor vision.
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Somnolence.
How Is Adiposogenital Dystrophy Diagnosed?
Diagnosing adiposogenital dystrophy can be done with a combination of physical examination, laboratory investigations, and imaging studies.
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Physical examinations will reveal the characteristic eunuchoid structure with short stature.
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Blood and urine tests to determine the hypothalamus and pituitary function; these may include TSH test, FSH test, prolactin levels, GH test, etc.
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Imaging studies of the brain to screen for any tumor growth. These may include an x-ray of the skull, CT (computed tomography) of the head and neck, and MRI (magnetic resonance imaging ) of the brain.
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Blood cultures should be done in patients with suspected infection.
Adiposogenital dystrophy mimics the following conditions:
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Prader-Willi Syndrome - A condition caused due to depletion of the gene in chromosome 15.
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Bardet-Biedl Syndrome - It is a ciliopathic (a group of genetic alterations) genetic condition that causes characteristic symptoms like vision loss, obesity, polydactyly (multiple fingers), hypogonadism, and renal failure.
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Borjeson Syndrome - An extremely rare genetic condition known to cause hypogonadism, obesity, intellectual disability, and seizures.
The above three conditions can be differentiated from adiposogenital dystrophy with the help of methylation analysis (study of chromosomal pattern).
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Hypogonadotropic Hypogonadism - Also known as secondary or central hypogonadism, is a condition characterized by hypogonadism due to impaired secretion of gonadotropins (peptide hormones) by the pituitary gland. It can be differentiated from adiposogenital dystrophy with the help of blood and urinalysis.
How Is Adiposogenital Dystrophy Treated?
Adiposogenital dystrophy is an acquired condition; the severity of the condition depends on the type of underlying abnormalities. Treatment is done on an individual basis, for example-
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If the condition is caused due to a tumor or lesion in the brain, surgery may be necessary to remove it.
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Hormone replacement therapy is useful to diminish the negative effects of the patients' underperforming endocrine system. This includes the administration of human chorionic gonadotropin and testosterone in males and estrogen and estrogen-progestin therapy in females.
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The characteristics of obesity and weight can be managed with the help of diet and exercise; however, in extreme cases, the healthcare provider might suggest bariatric surgeries like gastric bypass surgery and adjustable gastric banding.
The condition primarily affects adolescent boys, which is very difficult to deal with emotionally; it is even more difficult if there are associated sexual issues. This can be addressed with the help of counseling and psychotherapy. An early diagnosis can also help to reduce these negative effects.
Conclusion:
Adiposogenital dystrophy is a rare acquired condition that can affect the autonomic and endocrine systems. Although it is not life-threatening, the associated symptoms can cause distress in the affected individual and their families. However, prompt diagnosis and treatment can reverse the condition without lasting consequences.