Introduction:
Abderhalden–Kaufmann–Lignac syndrome, more commonly called nephropathic cystinosis, is a rare disease that usually appears during infancy and in children at a young age. It is a life-long condition, but cysteamine therapy and kidney transplantation are some treatment options available that have allowed the people affected with this condition to live longer.
What Is Abderhalden–Kaufmann–Lignac Syndrome?
Abderhalden–Kaufmann–Lignac syndrome is a rare genetic disorder that occurs during infancy and early childhood. It is also known as nephropathic cystinosis, the most severe form.
Cystinosis is a disease that results from an abnormal buildup of a particular amino acid called cystine. It is a rare but severe disease with a lifelong impact and can affect many body parts.
Cystinosis is an inherited disease, which means that it gets passed down through families.
A fault in the gene for the protein cystinosin causes problems with the way cystine gets stored in the body. Cystinosis is a recessive genetic disorder, and the affected person must inherit a copy of the abnormal gene from each parent to develop the disease.
In those people affected with cystinosis, cystine buildup in the body can lead to the formation of crystals. Cystinosis can have an impact on several parts of the body, including the brain, muscles, eyes, heart, white blood cells, pancreas, and thyroid. Cystinosis can also cause severe problems with the kidneys. There are three types of cystinosis that depend on when the symptoms appear first (known as onset):
-
Infantile (early-onset) cystinosis.
-
Later childhood or adolescent (late-onset) cystinosis.
-
Adult cystinosis.
The infantile or early-onset form is seen in about 95 percent of patients with cystinosis, making it the most common variant of this disorder. Most of these patients develop kidney problems.
Infantile or early-onset cystinosis is also known as nephropathic cystinosis. This term is used because cystinosis-affected individuals can have severe problems with their kidneys. Infants are most commonly affected by nephropathic cystinosis. They can develop a condition called Fanconi syndrome, which means that their kidneys are unable to absorb minerals and nutrients, such as potassium and sodium. As a result, these essential nutrients get lost in the urine. When these infants become children, they are at an increased risk of developing worsening kidney disease that eventually leads to kidney failure. This means that the kidneys can no longer work. At that stage, the only thing that could help to survive is either dialysis or a kidney transplant. With a lack of appropriate treatment, cystinosis-affected children can develop kidney failure by around 10 to 12 years.
People with adult cystinosis usually do not have kidney-related problems. Instead, they mostly have light sensitivity or photophobia. This is why this form of cystinosis can also be termed ocular cystinosis.
What Are the Symptoms of Abderhalden–Kaufmann–Lignac Syndrome?
The symptoms of Abderhalden-Kaufmann-Lignac syndrome include the following-
-
Slow growth.
-
Developmental delay.
-
Dwarfism (short stature due to genetic or medical condition).
-
Excess thirst.
-
Dehydration.
-
Frequent urination.
-
Difficulty swallowing.
-
Muscle wasting.
-
Osteoporosis (brittle and fragile bones).
-
Rickets (soft bowed bones).
-
Occasional light sensitivity (photophobia).
-
Aminoaciduria (abnormal amounts of amino acids in urine).
-
Renal tubular disease.
-
Low blood potassium levels.
-
Glucose in the urine.
-
Cysteine deposits in the cornea and conjunctiva of the eye.
What Causes Abderhalden–Kaufmann–Lignac Syndrome?
Abderhalden–Kaufmann–Lignac syndrome is caused by mutations (alterations) in the CTNS gene on chromosome 17p13. This gene is inherited in an autosomal recessive inheritance pattern. For a disease that has an autosomal recessive inheritance pattern, both the parents of the patient carry the gene (called the carrier) but are not themselves affected by the disease. They have one abnormal gene that has undergone mutation (recessive gene) and one normal gene (dominant gene) for the condition.
How Is Abderhalden–Kaufmann–Lignac Syndrome Diagnosed?
Abderhalden–Kaufmann–Lignac syndrome or nephropathic cystinosis is diagnosed using different methods, which include-
-
A physical examination is performed to look for signs of the disease. For example, the healthcare provider usually examines the eyes to check if cystine crystals are accumulated (signs of eye issues appear after two years of age).
-
Personal and family medical histories are also checked.
-
The doctor can also do a genetic test to help confirm a diagnosis.
Measuring the amount of cystine in WBCs (white blood cells) comprises one of the major tests for diagnosing cystinosis. Two tests can measure how well the kidneys are working-
-
Urine test called ACR (albumin to creatinine ratio).
-
Blood test to estimate GFR (glomerular filtration rate).
What Is the Treatment for Abderhalden–Kaufmann–Lignac Syndrome?
Infants and young children affected with Abderhalden–Kaufmann–Lignac syndrome might require receiving fluid and electrolytes, such as sodium and potassium. For problems with weaker bones, vitamin D and phosphate salts might also be given. For individuals developing diabetes, it is usually managed with insulin, a low-sugar diet, or other medications that help control sugar in the blood.
Infants and younger children with Abderhalden–Kaufmann–Lignac syndrome might eventually require a kidney transplant if their kidneys stop working. People with kidney transplants need to take certain medicines and do other essential things to maintain their health.
Certain medications, called cystine-depleting medicines, can help lower the amount of cystine in the body. As a result, they can improve symptoms and help delay kidney and other body parts complications. All people with cystinosis are required to take this medicine throughout their lives. The effectiveness of these medications is determined by measuring the quantity of cystine in white blood cells.
Conclusion:
With the help of kidney transplantation, cystine therapy, and other medicines, people with Abderhalden–Kaufmann–Lignac syndrome today live longer into adulthood, provided their treatment starts early and appropriately. However, this disease usually has a lifelong impact, so people with cystinosis need to keep up with their medical appointments and treatments. They also need to continue their medications and follow the treatment plan as recommended by their healthcare provider.
