~ Patient folder ~
A few days ago a friend here in India told me his nephew got diagnosed with IgA Nephropathy, and he asked me for some information. As the family was still under the impression their son might not reach 15, i decided to write a little document for them. Here I’ll share it with you. Feedback and suggestions are welcome!
What is IgA Nephropathy and how is it
caused?
IgA Nephropathy is a ‘disease’ which affects the kidneys. IgA is a class of immunoglobulin, in other words IgA is a type of antibodies (the body’s natural defence against foreign entities like bacteria and viruses). Nephropathy is a fancy word that says as much as kidney disease or damage. Sometimes IgA gets deposited in the filtration system of the kidneys, causing inflammation and damage to the tissue. Why and how the IgA immune complexes are deposited in the kidney is not entirely sure yet, however, it appears to happen more often after a respiratory tract or gastro-intestinal infection and in combination with certain genetic traits.
It’s important to realise it’s no one’s fault if a child (or adult for that matter) develops IgA nephropathy, it just a matter of genetics, environment and change.
What are the symptoms and how is IgA Nephropathy diagnosed
The presentation of Nephropathy is varied, ranging from asymptomatic to acute kidney failure. Other symptoms are haematuria (passing blood in urine), proteinuria (passing proteins in urine), oedema and hypertension. In childhood haematuria is the most common presenting symptom, and hypertension the least common.
As you probably know by now, your physician might want to take urine samples to test for red blood cells and protein. To confirm the diagnosis a biopsy of the kidney is essential. A very small piece of kidney is removed from the body with something similar to a needle, this is a very safe procedure, but like all medical procedure there are some potential risks. The pathologist will apply a fluorescent label, which only sticks to IgA, to the tissue sample. He will then look to the tissue with a microscope. If he can see fluorescent structures lighting up, it means that there are IgA depositions in the kidney and the patient has IgA nephropathy.
What are the consequences?
Overall, 20-30 % of IgA nephropathy cases will progress in to renal failure in 20 years of onset. However, this number is highly variable between different groups of people and is smaller for children. Researchers and clinicians have tried to come-up with some factors that can predict the severity and rate of progression of the disease. They found that children who are younger at the presentation of the disease and who had little or no proteinuria (protein in urine) seem to be less likely to develop severe kidney failure. The opposite seems to be the case too, the older children are, and the more protein in urine at the time of presentation, the more likely it becomes for them to develop kidney failure. High Creatinine, a waste product, in the blood is also associated with higher incidence of disease progression. Unlike adults, hypertension and acute kidney failure at time of presentation in children is often reversible. Certain findings of the pathology test are also correlated with better or worse outcomes, for example whether the IgA depositions are focal or generalised (the latter one being associated with higher number of progression). Your physician will discuss the results of the pathology reports and their implications with you.
So keep in mind that only a small number of children, who have IgA nephropathy in childhood, will develop progressive nephropathy and kidney failure. This process usually takes more than 10 years. If the kidneys are so badly damaged, that they fail to filtrate the blood of enough of the waste products to keep a person functioning, it is called severe or end stage kidney failure. This happens when 90% or more of the kidney function is lost, at this stage haemodialysis will be initiated and kidney transplantation considered. However, the fast majority of children will have little or no permanent damage of their kidney function.
How can it be treated?
There is currently no treatment to cure IgA nephropathy. The general approach is to try to slow renal damage for example by controlling blood pressure. In a number of cases the IgA nephropathy will resolve spontaneously.
Generally no treatment is advised to patients with isolated haematuria without or with only minimal proteinuria. After the initial period, once or twice yearly follow up of disease progression is recommended. For patients with severe kidney disease at onset or rapid progression a form of corticosteroid treatment or other immunosuppressive drugs are mostly initiated (frequently used drugs are: prednisone and methylprednisolone). Other options are ACE-inhibitors or statins, however these are a lot less frequently used in paediatric patients.
Every patient and situation is unique and depending on the specific situation of your child the physician will make decisions regarding the treatment. Discuss the options and there side-effects with your physician.
What can you do yourself?
Very little! Lots of people will give you well intentioned, but ill-informed advice. A few of them are listed here.
For 25 years people have been researching the effects of fish oil supplements on kidney disease. Analyses of all these findings have been limited by the poor quality of available studies. The last word is not said about the benefits of fish-oil in IgA nephropathy, further and properly conducted research is necessary. However, current guidelines suggest it might be used.
A low antigen diets has been suggested. This is a diet low in gluten, dairy products, eggs, and most meats. There is not sufficient evidence to support this diet and is therefore not recommend. Only in severe kidney failure a change of dietary intake is advisable. If you are uncertain about some foods or diets you should discuss this with your physician.
Clean drinking water is recommended for all children, not only for those with kidney disease.
If you are not sure about something discuss it with your physician. He is the one who’s most informed about the situation of your child.
~ Take Care! ~
Resources:
- v Norishige Yoshikawa, Ryojiro Tanaka, Kazumoto Iijima. Pathophysiology and treatment of IgA nephropathy in children. Pediatr Nephrol (2001) 16:446–457
- v Daniel C Cattran MD, Gerald B Appel MD. Treatment and prognosis of IgA nephropathy. Last literature review version 18.3: september 2010, This topic last updated: oktober 7, 2010. UpToDate. Information retrieved on 30/01/11.
- v Jonathan Barratt PhD MRCP, John Feehally DM FRCP. Pathogenesis of IgA nephropathy. Last literature review version 18.3: september 2010, This topic last updated: april 28, 2010. Information retrieved on 30/01/11.
- Fassett RG, Gobe GC, Peake JM, Coombes JS. Omega-3 polyunsaturated fatty acids in the treatment of kidney disease. Am J Kidney Dis. 201