Introduction
Dense deposit disease is a rare medical condition or an orphan disease that affects the kidneys in children and young adults. This disease does not have any definite sexual predilection. Studies report that this disease mainly occurs due to the dysregulation of complement pathways. However, nothing has been known about the role of genetics and autoantibodies. In addition, no targeted treatment therapies are available for affected patients. Hence, the disease often progresses to end-stage renal failure within ten years of diagnosis. DDD is more prevalent in patients who have undergone transplants. However, detailed studies need to be conducted to identify the genetic factors involved in the condition.
What Is Dense Deposit Disease?
DDD, or membranoproliferative glomerulonephritis type II, is a rare autoimmune condition that affects the eyes and the kidneys. As the name suggests, the disease is known to affect the kidneys' tiny filtration units or glomeruli. In simple terms, DDD prevents the kidneys from filtering the blood. As a result, toxins and other waste products accumulate within the bloodstream. The disease has been named so because proteins which are an integral part of the immune system, attack and adhere to the glomerular basement membrane. As a result, they accumulate as thick patches known as dense deposits. Studies report that half of the patients diagnosed with this condition tend to progress to kidney failure within ten years. In addition, people diagnosed with this condition tend to develop retinal deposits that appear yellowish-white and are known as drusen.
What Are the Causes of Dense Deposit Disease?
Dense deposit disease is an autoimmune condition that implies that the antibodies attack the body's healthy cells. Normally, the immune system can distinguish between foreign bodies and the body's own cells. In addition, the immune system has the ability to destroy pathogenic organisms and trigger an inflammatory response. However, dense deposit disease hampers the functioning of the immune system resulting in autoimmune conditions. In addition, the disease can also be caused by mutations in C3 and CFH genes. These genes synthesize complement factor H protein to regulate the body's immune system. The protein becomes defective due to genetic mutations resulting in an overactive immune system that attacks the kidneys. However, genetic mutations are not always the cause of dense deposit disease. Pregnancy, chronic diseases, infections, and cancer can also play a vital role.
What Are the Signs and Symptoms of Dense Deposit Disease?
The symptoms of DDD usually initiate in children around two to 11 years of age. DDD primarily affects the kidneys; hence the initial symptoms are similar to those of kidney diseases and proteinuria (the presence of proteins in the urine). As a result, the urine appears foamy, pink, or red colored. The other signs and symptoms of dense deposit disease are listed below:
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Weight gain because the kidneys have lost their ability to filter blood or eliminate excess fluids.
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Swelling or edema around the eyes, feet, or ankle.
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Fatigue.
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Confusion.
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Loss of appetite.
What Are the Clinical Manifestations of Dense Deposit Disease?
DDD affects children and adults without any particular sexual predilection. Recent studies suggest that 90 percent of patients with DDD had proteinuria, 84 percent had hematuria, and 50 percent of them had hypertension. Some patients present with partial lipodystrophy along with DDD. It is a condition characterized by the loss of fat from the face, arms, neck, forearms, shoulder, and thorax. Kidney diseases can occur before or after fat loss. DDD can progress to end-stage renal failure with a mean survival time of 10.2 years. Children and females are more likely to have aggressive outcomes and disease courses. In addition, graft failure has been observed in 50 percent of patients.
How Is Dense Deposit Disease Diagnosed?
Dense deposit disease is diagnosed through a kidney biopsy. It is a diagnostic procedure wherein parts of kidney tissues are collected and examined using a microscope. A kidney biopsy is done to evaluate cancer and other kidney problems and determine the treatment plan. A biopsy can also be done on transplanted kidneys to check the signs and symptoms of rejection. The biopsy is usually done under local or general anesthesia. In addition, a blood test can also be done for autoantibodies or nephritic factors that hamper the functioning of the immune system. In addition, the blood report of a patient helps determine the general health of a patient.
What Are Some of the Treatment Methods for Dense Deposit Disease?
There is no specific treatment method available for dense deposit disease. However, some treatment methods help prevent the progression of kidney diseases and manage kidney failure. The treatment methods include:
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The patient can be counseled about lifestyle changes that help keep blood pressure under control. Controlled blood pressure prevents damage to the kidneys.
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The patient can take angiotensin-converting enzyme inhibitors or angiotensin receptor blockers to overcome the symptoms associated with proteinuria and kidney damage.
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Plasma replacement therapy can be done for patients with mutations in the CFH gene to remove the faulty complement factor proteins.
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Plasmapheresis can be done to eliminate the nephritic factors from blood serum.
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Dialysis is usually recommended for patients with kidney failure.
There is no specific treatment plan available for drusen, but some therapies are used for age-related macular degeneration. It is a condition wherein a person has impaired vision. Hence, people with DDD must consult an ophthalmologist regularly.
What Are Some of the Complications of Dense Deposit Disease?
Multiple organ failure can occur when kidney disease progresses to kidney failure or end-stage renal failure. Some of the complications of DDD are listed below:
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Heart diseases.
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Bone diseases.
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Nervous problems.
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Gastrointestinal diseases.
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Peripheral neuropathy.
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Restless leg syndrome.
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Dry skin.
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Itching.
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High blood pressure or hypertension.
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Reduced ability to fight infections.
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Color blindness.
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Loss of vision.
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Impaired night vision.
Conclusion
Dense deposit disease is a condition wherein kidneys lose their ability to filter blood. As a result, waste products or toxins accumulate in the bloodstream resulting in serious complications. Hence, the patient must consult the doctor to know more about the treatment and prevention methods.
