De Toni Debre Fanconi syndrome is the name given to a genetic disease. It involves reabsorption of various substances in the kidney.
What is de Toni Debre Fanconi syndrome?
De Toni-Debre-Fanconi syndrome is also known as De Toni-Debre-Fanconi complex, De Toni-Fanconi syndrome, or glucose-amino acid diabetes. This refers to a renal resorption disorder of the proximal tubule, which is a section of the renal tubule. De Toni-Debre-Fanconi syndrome is a hereditary disease and results in reabsorption of various substances. These include amino acids, glucose, and inorganic phosphorus. As a result, pathological excretion of glucose, phosphate and amino acids occurs. De Toni-Debre-Fanconi syndrome was first described by the Italian physician Giovanni de Toni (1896-1973) and the Swiss Guido Fanconi (1892-1979), who also gave the disease its name. De Toni-Debre-Fanconi syndrome is one of the rather rare diseases. In Europe, about 50 cases of the infantile type are known. Secondary forms, however, show up more frequently.
Causes
De Toni Debre Fanconi syndrome can be divided into three distinct forms. These are primary idiopathic Fanconi syndrome, which is inherited in an autosomal recessive manner but can also occur spontaneously. Fanconi syndrome of the adult type is less severe than Fanconi syndrome of the infantile type. The third form is secondary Fanconi syndrome. This occurs concomitantly with hereditary metabolic diseases such as cystinosis or Lowe’s syndrome. In addition, it is secondary to Sjögren’s syndrome, amyloidosis, tumors, poisoning, or as an undesirable side effect of medication. De Toni-Debre-Fanconi syndrome is mostly a hereditary disease. While the infantile type of the syndrome is inherited in an autosomal recessive manner, the adult type is inherited in an autosomal dominant manner. In the case of De Toni-Debre-Fanconi syndrome, there is a generalized resorption disorder of the proximal tubule. The pathomechanism of the syndrome has not yet been fully elucidated. An ischemia-induced ATP deficiency or Na+-/K+ATPase insufficiency is assumed. The consequence of these is that various substances such as glucose, amino acids or ions such as phosphate are no longer secreted from the urine and excreted. This in turn leads to aminoaciduria, hypercalciuria including hypokalemia, hyperphosphaturia associated with a disturbance of phosphate balance, and glucosuria including osmotic diuresis. In addition to the hereditary form of De Toni-Debre-Fanconi syndrome, which is genetically determined, there is also an acquired form. This is caused by metabolic diseases such as fructose intolerance or Wilson’s disease, ischemia, or nephrotoxic substances such as heavy metals or drugs.
Symptoms, complaints, and signs
The symptoms of De Toni-Debre-Fanconi syndrome depend on whether it is an infantile or adult form of the disease. In the idiopathic primary syndrome, which occurs in infancy, symptoms such as short stature, febrile episodes, and vomiting appear between the ages of 2 and 3 years. In addition, the affected children suffer from rickets, which is vitamin D resistant. Furthermore, there is severe pain in the bones. Even fractures are within the realm of possibility. If the kidney insufficiency (kidney weakness) that also occurs is not treated with blood washing (dialysis) or transplantation of the kidney, the affected child is even threatened with death. If the symptoms of De Toni-Debre-Fanconi syndrome do not appear until adulthood, there is usually no need to fear life-threatening consequences. The adult form of the syndrome is characterized by muscle hypotonia, polydipsia (abnormal thirst) or softening of the bones (osteomalacia). Furthermore, there is a risk of complications due to the deficiencies. These include hypoglycemia (low blood sugar), spontaneous bone fractures, neurological disorders, and hypokalemic symptoms. In addition, global renal failure may occur.
Diagnosis and course
To diagnose de Toni Debre Fanconi syndrome, the examining physician first addresses the patient’s medical history. Furthermore, he performs a physical examination as well as a laboratory examination.By urine status, it is possible to detect aminoaciduria or glucosuria. In the case of multiple myeloma, proteinuria can be detected. The phosphate level in the blood serum is low. Sometimes, hypokalemia can also be detected. X-rays can be taken to diagnose secondary sequelae of De Toni-Debre-Fanconi syndrome such as osteomalacia or rickets. Sometimes a kidney biopsy (tissue sampling) is also performed. The course of De Toni-Debre-Fanconi syndrome depends on its form. For example, the prognosis of the infantile form is considered unfavorable, because without a kidney transplant, death sets in between ten and twelve years due to renal failure. On the other hand, if it is the adult form, which is only seen in adults, life expectancy is normal.
When should you see a doctor?
If symptoms such as short stature, fever episodes, and vomiting are noticed between the ages of two and three, the condition may be De Toni Debre Fanconi syndrome. A visit to the pediatrician is recommended if the symptoms do not resolve on their own or if additional symptoms develop. In general, if there are signs of a serious condition, always see a doctor. In case of severe bone pain or even fractures, the ambulance should be alerted or the affected child should be taken to the hospital. The same applies to signs of renal insufficiency or rickets. If the symptoms do not appear until adulthood, a doctor must be consulted with abnormal thirst, bone complaints and other typical signs. Medical advice is needed at the latest in the event of complications such as hypoglycemia, neurological disorders or spontaneous bone fractures. In addition to the family doctor, a specialist in hereditary diseases or an internist can also be consulted. In the case of non-specific symptoms, it is best to contact the emergency medical service first. However, a medical clarification is recommended in any case with mentioned complaints.
Treatment and therapy
In the treatment of De Toni-Debre-Fanconi syndrome, both causal and symptomatic therapy are possible. If the patient suffers from the secondary form, the cause of the primary disease is treated. Standard therapy includes administration of vitamin D3 or calcitriol to treat vitamin D-resistant rickets. Hydrochlorothiazide is also given to reduce electrolyte loss through the kidneys. Many small meals rich in protein and carbohydrates are also considered helpful. In addition, the patient must consume one to three liters of fluid per day. At the same time, it is important to reduce the intake of table salt. It is also important to compensate for the loss of phosphate, potassium and sodium. Acidosis is in turn balanced by buffer solutions. If a hereditary proximal disorder is present, only symptomatic therapy is possible, in which the patient receives sodium bicarbonate, phosphate, glucose and potassium. Regular monitoring of kidneys and bones is also considered important.
Outlook and prognosis
Because De Toni-Debre-Fanconi syndrome is a genetic disorder, it cannot be treated causally, only symptomatically. Self-cure does not occur with this syndrome. If left untreated, De Toni-Debre-Fanconi syndrome can lead to complete renal failure, eventually resulting in the death of the affected individual. Patients are then dependent on a donor kidney or dialysis. Similarly, short stature, vomiting or various deficiency symptoms may result from the syndrome. Quality of life and life expectancy are significantly reduced. In children, the syndrome also leads to disturbed and slowed development. Bone fractures and slowed wound healing are common. De Toni Debre Fanconi syndrome can usually be treated relatively well with the help of medication. This relieves all symptoms and results in a positive course of the disease. However, patients are dependent on taking these medications for the rest of their lives, since the syndrome cannot be completely cured. Furthermore, regular examinations of the internal organs must be performed to avoid complications. With early therapy and successful treatment, there is no decreased life expectancy.
Prevention
De Toni-Debre-Fanconi syndrome is considered a genetic disease. Therefore, there are no preventive measures.
Aftercare
In most cases of De Toni Debre Fanconi syndrome, the affected person has few options for direct aftercare. The affected person must see a physician early in the course of this disease to avoid further complications. Since this is a genetic disease, there is no complete cure. If there is a desire to have children, genetic counseling and testing may be useful to prevent the recurrence of the disease. Self-cure does not occur in De Toni-Debre-Fanconi syndrome. In most cases, patients with this disease must take medication. It is always important to ensure that the medication is taken regularly and in the correct dosage. In the case of children, the parents must control the intake. Patients should also drink plenty of fluids and avoid salt as far as possible so as not to put unnecessary strain on the kidneys. Since De Toni Debre Fanconi syndrome can cause severe kidney problems, regular checks and examinations of the internal organs are very important. Especially the bones and the kidneys have to be checked. It cannot be universally predicted whether the syndrome will result in a decreased life expectancy for the patient.
Here’s what you can do yourself
In addition to the genetic hereditary form of De Toni-Debre-Fanconi syndrome, it still occurs in an acquired form. Patients themselves cannot take any action that is causative against the genetic variant of the disorder. The infantile form of the disease is particularly severe and usually becomes apparent between the ages of two and three. Parents should then insist that their child be treated by a doctor who has actually had experience with this rather rare disease. Specialists can be found through the medical association or with the help of the health insurance company. Accompanying symptoms of the frequently occurring short stature, such as tension, muscle pain or restricted motor skills, can usually be alleviated by physiotherapy started at an early stage. As soon as the children begin to suffer emotionally from their short stature, a child psychologist should be consulted. If the condition is acquired rather than genetic, the first thing to do is to identify the trigger. This may be, for example, metabolic disorders, fructose intolerance or poisoning with heavy metals. Medications can also be responsible for an acquired De Toni-Debre-Fanconi syndrome. If the disease correlates with the patient’s lifestyle, for example, diet or occupation, the patient must be prepared to modify his or her lifestyle. If a modification of the diet is necessary, an ecotrophologist should be consulted. If the occupation can no longer be practiced, the vocational counseling of the employment agency should be called upon at an early stage. Trade unions also provide advice free of charge in such cases.
