What are the other Names for this Condition? (Also known as/Synonyms)

• C1q Nephropathy Disorder

What is C1q Nephropathy? (Definition/Background Information)

• C1q Nephropathy is a kidney disease in which a large amount of protein is lost in the urine. It is one of the many diseases that can cause the nephrotic syndrome
• C1q is a normal protein in the immune system, and can be found floating in the circulation of most healthy people. In C1q Nephropathy, however, this protein can also be found deposited throughout the kidneys
• It has been thought to be a subgroup of primary focal segmental glomerulosclerosis or to be a combination of several disease groups rather than a single disease
• Criteria diagnosis includes C1q deposits on the kidney and no evidence of systemic lupus erythematosus
• Both children and adult patients may have no symptoms, except for the presence of blood or protein in the urine, or  present with swelling of the feet and legs, high blood pressure and kidney insufficiency
• The treatment of C1q Nephropathy includes corticosteroids and other immunosuppressive agents

(Source: C1q Nephropathy; Genetic and Rare Disease Information Center (GARD) of National Center for Advancing Translational Science (NCATS), USA.)

Who gets C1q Nephropathy? (Age and Sex Distribution)

• C1q Nephropathy is a rare congenital disorder. The presentation of symptoms most often begin in childhood
• Both males and females may be affected
• Worldwide, individuals of all racial and ethnic groups may be affected

What are the Risk Factors for C1q Nephropathy? (Predisposing Factors)

• Currently, no risk factors have been clearly identified for C1q Nephropathy

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one’s chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of C1q Nephropathy? (Etiology)

• The exact genetic cause of C1q Nephropathy is not known at the present time
• The normally occurring C1q protein in blood gets deposited in kidney tissues. It is believed that this may elicit an immune response from the kidneys, causing inflammation and subsequent damage to the organ

What are the Signs and Symptoms of C1q Nephropathy?

The signs and symptoms of C1q Nephropathy may not be apparent in the initial stages. However, as the disease progresses, the following signs and symptoms may become evident:

• Presence of blood or protein in the urine
• Swelling of the feet and legs
• High blood pressure 
• kidney insufficiency

(Source: C1q Nephropathy; Genetic and Rare Disease Information Center (GARD) of National Center for Advancing Translational Science (NCATS), USA.)

How is C1q Nephropathy Diagnosed?

C1q Nephropathy is diagnosed on the basis of the following information:

• Complete physical examination
• Thorough medical history evaluation
• Assessment of signs and symptoms
• Laboratory tests
• Imaging studies
• Biopsy of kidney tissue, to check for/confirm C1q protein deposits in the kidneys
• Exclusion of systemic lupus erythematosus

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of C1q Nephropathy?

The complications of C1q Nephropathy may include:

• Heart attack
• Stroke
• Chronic kidney failure
• End-stage renal disease

Complications may occur with or without treatment, and in some cases, due to treatment also.

How is C1q Nephropathy Treated?

The treatment for C1q Nephropathy may include:

• Angiotensin converting enzyme (ACE) inhibitors 
• Angiotensin II receptor blockers
• Corticosteroids and other immunosuppressive agents
• Dialysis for chronic kidney failure
• Kidney transplantation for end-stage kidney disease

How can C1q Nephropathy be Prevented?

• The exact cause of C1q Nephropathy is not known, and hence, no guidelines or preventive methods are available at the present time 
• Regular medical screening at periodic intervals with tests and physical examinations are recommended
• Active research is currently being performed to explore the possibilities for treatment and prevention of disorders such as C1q Nephropathy

What is the Prognosis of C1q Nephropathy? (Outcomes/Resolutions)

• The prognosis of C1q Nephropathy is dependent upon the severity of the signs and symptoms and associated complications, if any
• Individuals with mild conditions have better prognosis than those with severe symptoms and complications
• Typically, the prognosis may be assessed on a case-by-case basis

Additional and Relevant Useful Information for C1q Nephropathy:

• As a disorder, C1q Nephropathy is very similar to minimal change disease (MCD) and focal segmental glomerulosclerosis (FSGS)

The following DoveMed website link is a useful resource for additional information:

http://www.dovemed.com/diseases-conditions/rare-disorders/