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Prevention for Alström Syndrome is considered to be harder compared to other diseases/syndromes because it is an inherited condition. However, there are other options that are available for parents with a family history of Alström Syndrome. Genetic testing and counseling are available where individuals are able to meet with a genetic counselor to discuss risks of having the children with the disease. The genetic counselor may also help determine whether individuals carry the defective ALSM1 gene before the individuals conceive a child. Some of the tests the genetic counselors perform include chorionic villus sampling (CVS), Preimplantation genetic diagnosis (PGD), and amniocentesis. With PGD, the embryos are tested for the ALSM1 gene and only the embryos that are not affected may be chosen for implantation via in vitro fertilization.
The limited prognostic information available suggests that early diagnosis and appropriate treatment of infants and young children with classic Bartter Syndrome may improve growth and perhaps neurointellectual development. On the other hand, sustained hypokalemia and hyperreninemia can cause progressive tubulointerstitial nephritis, resulting in end-stage kidney disease (kidney failure). With early treatment of the electrolyte imbalances, the prognosis for patients with classic Bartter Syndrome is good.
It is possible to clinically detect Alström syndrome in infancy, but more frequently, it is detected much later, as doctors tend to detect symptoms as separate problems. Currently, Alström syndrome is often diagnosed clinically, since genetic testing is costly and only available on a limited basis.
A physical examination would be needed to properly diagnose the patient. Certain physical characteristics can determine if the patient has some type of genetic disorder. Usually, a geneticist would perform the physical examination by measuring the distance around the head, distance between the eyes, and the length of arms and legs. In addition, examinations for the nervous system or the eyes may be performed. Various imaging studies like computerized tomography scans (CT), Magnetic Resonance Imaging (MRI), or X-rays are used to see the structures within the body.
Family and personal medical history are required. Information about the health of an individual is crucial because it provides traces to a genetic diagnosis.
Laboratory tests, particularly genetic testing, are performed to diagnose genetic disorders. Some of the types of genetic testing are molecular, biochemical, and chromosomal. Other laboratory tests performed may measure levels of certain substances in urine and blood that can also help suggest a diagnosis.
While patients should be encouraged to include liberal amounts of sodium and potassium in their diet, potassium supplements are usually required, and spironolactone is also used to reduce potassium loss.
Nonsteroidal anti-inflammatory drugs (NSAIDs) can be used as well, and are particularly helpful in patients with neonatal Bartter's syndrome.
Angiotensin-converting enzyme (ACE) inhibitors can also be used.
The diagnosis can usually be made on a combination of clinical, family history and biopsy criteria.
Genetic testing plays an increasingly important role in confirming the diagnosis where the clinical features do not amount to proof.
Most asymptomatic individuals with Gitelman syndrome can be monitored without medical treatment. Potassium and magnesium supplementation to normalize low blood levels of potassium and magnesium is the mainstay of treatment. Large doses of potassium and magnesium are often necessary to adequately replace the electrolytes lost in the urine. Diarrhea is a common side effect of oral magnesium which can make oral replacement difficult but dividing the dose to 3-4 times a day is better tolerated. Severe deficits of potassium and magnesium require intravenous replacement. If low blood potassium levels are not sufficiently replaced with oral replacement, aldosterone antagonists (such as spironolactone or eplerenone) or epithelial sodium channel blockers such as amiloride can be used to decrease urinary wasting of potassium.
Gitelman syndrome is estimated to have a prevalence of 1 in 40,000 people.
Medical diagnosis of CGL can be made after observing the physical symptoms of the disease: lipoatrophy (loss of fat tissues) affecting the trunk, limbs, and face; hepatomegaly; acromegaly; insulin resistance; and high serum levels of triglycerides. Genetic testing can also confirm the disease, as mutations in the AGPAT2 gene is indicative of CGL1, a mutation in the BSCL2 gene is indicative of CGL2, and mutations in the CAV1 and PTRF genes are indicative of CGL3 and CGL4 respectively. Physical diagnosis of CGL is easier, as CGL patients are recognizable from birth, due to their extreme muscular appearance, which is caused by the absence of subcutaneous fat.
CGL3 patients have serum creatine kinase concentrations much higher than normal (2.5 to 10 times the normal limit). This can be used to diagnose type 3 patients and differentiate them from CGL 1 and 2 without mapping their genes. Additionally, CGL3 patients have low muscle tone when compared with other CGL patients.
Since the symptoms caused by this disease are present at birth, there is no “cure.” The best cure that scientists are researching is awareness and genetic testing to determine risk factors and increase knowledgeable family planning. Prevention is the only option at this point in time for a cure.
Because the variability of this disease is so great and the way that it reveals itself could be multi-faceted; once diagnosed, a multidisciplinary team is recommended to treat the disease and should include a craniofacial surgeon, ophthalmologist, pediatrician, pediatric urologist, cardiologist, pulmonologist, speech pathologist, and a medical geneticist. Several important steps must be followed, as well.
- Past medical history
- Physical examination with special attention to size and measurements of facial features, palate, heart, genitourinary system and lower respiratory system
- Eye evaluation
- Hypospadias assessment by urologist
- Laryngoscopy and chest x-ray for difficulties with breathing/swallowing
- Cleft lip/palate assessment by craniofacial surgeon
- Assessment of standard age developmental and intellectual abilities
- Anal position assessment
- Echocardiogram
- Cranial imaging
Many surgical repairs may be needed, as assessed by professionals. Furthermore, special education therapies and psychoemotional therapies may be required, as well. In some cases, antireflux drugs can be prescribed until risk of breathing and swallowing disorders are removed. Genetic counseling is highly advised to help explain who else in the family may be at risk for the disease and to help guide family planning decisions in the future.
Because of its wide variability in which defects will occur, there is no known mortality rate specifically for the disease. However, the leading cause of death for people with Opitz G/BBB syndrome is due to infant death caused by aspiration due to esophageal, pharyngeal or laryngeal defects.
Fortunately, to date there are no factors that can increase the expression of symptoms of this disease. All abnormalities and symptoms are present at birth.
Management of autoimmune polyendocrine syndrome type 2 consists of the following:
Diagnosis often can be made through clinical examination and urine tests (excess mucopolysaccharides are excreted in the urine). Enzyme assays (testing a variety of cells or body fluids in culture for enzyme deficiency) are also used to provide definitive diagnosis of one of the mucopolysaccharidoses. Prenatal diagnosis using amniocentesis and chorionic villus sampling can verify if a fetus either carries a copy of the defective gene or is affected with the disorder. Genetic counseling can help parents who have a family history of the mucopolysaccharidoses determine if they are carrying the mutated gene that causes the disorders.
There is currently no treatment or cure for Waardenburg syndrome. The symptom most likely to be of practical importance is deafness, and this is treated as any other irreversible deafness would be. In marked cases there may be cosmetic issues. Other abnormalities (neurological, structural, Hirschsprung disease) associated with the syndrome are treated symptomatically.
Subtypes of the syndrome are traceable to different genetic variations and presentations:
Type III is also known as Klein-Waardenburg syndrome, and type IV is also known as Waardenburg-Shah syndrome.
Metformin is the main drug used for treatment, as it is normally used for patients with hyperglycemia. Metformin reduces appetite and improves symptoms of hepatic steatosis and polycystic ovary syndrome. Leptin can also be used to reverse insulin resistance and hepatic steatosis, to cause reduced food intake, and decrease blood glucose levels.
Differential diagnosis includes nephrogenic diabetes insipidus, neurogenic/central diabetes insipidus and psychogenic polydipsia. They may be differentiated by using the water deprivation test.
Recently, lab assays for ADH are available and can aid in diagnosis.
If able to rehydrate properly, sodium concentration should be nearer to the maximum of the normal range. This, however, is not a diagnostic finding, as it depends on patient hydration.
DDAVP can also be used; if the patient is able to concentrate urine following administration of DDAVP, then the cause of the diabetes insipidus is neurogenic; if no response occurs to DDAVP administration, then the cause is likely to be nephrogenic.
A large British study from 2008 found a median estimated life expectancy of 11.6 years.
In terms of genetic testing, while it is done for "type 1" of this condition, "type 2" will only render (or identify) those genes which place the individual at higher risk. Other methods/exam to ascertain if an individual has autoimmune polyendocrine syndrome type 2 are:
- CT scan
- MRI
- Ultrasound
The primary treatment for type 1 tyrosinemia is nitisinone (Orfadin) and restriction of tyrosine in the diet. Nitisinone inhibits the conversion of 4-OH phenylpyruvate to homogentisic acid by 4-Hydroxyphenylpyruvate dioxygenase, the second step in tyrosine degradation. By inhibiting this enzyme, the accumulation of the fumarylacetoacetate is prevented. Previously, liver transplantation was the primary treatment option and is still used in patients in whom nitisinone fails.
Diagnosis involves consideration of physical features and genetic testing. Presence of split uvula is a differentiating characteristic from Marfan Syndrome, as well as the severity of the heart defects. Loeys-Dietz Syndrome patients have more severe heart involvement and it is advised that they be treated for enlarged aorta earlier due to the increased risk of early rupture in Loeys-Dietz patients. Because different people express different combinations of symptoms and the syndrome was identified in 2005, many doctors may not be aware of its existence, although clinical guidelines were released in 2014-2015. Dr. Harold Dietz, Dr. Bart Loeys, and Dr. Kenneth Zahka are considered experts in this condition.
Microlissencephaly can be diagnosed by prenatal MRI. MRI is better than ultrasound when it comes to detecting microlissencephaly or MSGP prenatally.
The ideal time for proper prenatal diagnosis is between the 34th and 35th gestational week which is the time when the secondary gyration normally terminates. In microlissencephaly cases, the primary sulci would be unusually wide and flat while secondary sulci would be missing.
At birth, lissencephaly with a head circumference of less than minus three standard deviations (< –3 SD) is considered microlissencephaly.
Although genetic diagnosis in patients with MLIS is challenging, exome sequencing has been suggested to be a powerful diagnostic tool.
Type 4 RTA is not actually a tubular disorder at all nor does it have a clinical syndrome similar to the other types of RTA described above. It was included in the classification of renal tubular acidoses as it is associated with a mild (normal anion gap) metabolic acidosis due to a "physiological" reduction in proximal tubular ammonium excretion (impaired ammoniagenesis), which is secondary to hypoaldosteronism, and results in a decrease in urine buffering capacity. Its cardinal feature is hyperkalemia, and measured urinary acidification is normal, hence it is often called hyperkalemic RTA or tubular hyperkalemia.
Causes include:
- Aldosterone deficiency (hypoaldosteronism): Primary vs. hyporeninemic (including diabetic nephropathy)
- Aldosterone resistance
1. Drugs: NSAIDs, ACE inhibitors and ARBs, Eplerenone, Spironolactone, Trimethoprim, Pentamidine
2. Pseudohypoaldosteronism
In some patients, RTA shares features of both dRTA and pRTA. This rare pattern was observed in the 1960s and 1970s as a transient phenomenon in infants and children with dRTA (possibly in relation with some exogenous factor such as high salt intake) and is no longer observed. This form of RTA has also been referred to as juvenile RTA.
Combined dRTA and pRTA is also observed as the result of inherited carbonic anhydrase II deficiency. Mutations in the gene encoding this enzyme give rise to an autosomal recessive syndrome of osteopetrosis, renal tubular acidosis, cerebral calcification, and mental retardation. It is very rare and cases from all over the world have been reported, of which about 70% are from the Magreb region of North Africa, possibly due to the high prevalence of consanguinity there.
The kidney problems are treated as described above. There is no treatment for the osteopetrosis or cerebral calcification.
Type 3 is rarely discussed. Most comparisons of RTA are limited to a comparison of types 1, 2, and 4.
Microlissencephaly is considered a more severe form than microcephaly with simplified gyral pattern. Microlissencephaly is characterized by a smooth cortical surface (absent sulci and gyri) with a thickened cortex (> 3 mm) and is usually associated with other congenital anomalies. Microcephaly with a simplified gyral pattern has too few sulci and normal cortical thickness (3 mm) and is usually an isolated anomaly.