HARARE – Today is World Kidney Day and the day was launched in 2006 by the International Society of Nephrology (ISN) and the International Federation of Kidney Foundations (IFKF) with the aim of creating a global awareness campaign on the importance of our kidneys. It is celebrated annually on the 2nd Thursday in March.
This year’s focus is on children because no one is immune to kidney ailments which can result in total kidney malfunction. We are, under normal conditions, born with two bean shaped kidneys situated at the middle of our backs just below the rib cage.
Each weighs about 150 grammes and is the size of a person’s fist. Within this organ are small tubular filtering units called nephrons. We are endowed with about a million of these in each kidney.
The functions of the kidney are many. The most well-known one is to remove waste. This comes from breakdown of food, and some from cellular and muscle activities. They maintain the internal environment of our body constant and optimal to sustain life.
The kidneys receive 25 percent of the blood pumped from heart which is 1,1litres per minute. 200 litres of blood (a drum) is filtered through the kidneys daily and only 1,5litres of urine is discarded as waste per day. This shows how the maintenance of the internal environment is achieved.
What is essential, from this process, is taken back into the body and what is waste is discarded in the urine. A large number of positive achievements are attained by the above processes. The salt content is maintained, the acidity is maintained and fluid balance is achieved among others. The blood pressure is maintained by the kidneys. The other less well known functions are the control of blood level i.e. haemoglobin, and bone integrity by processing Vitamin D and other hormonal interactions.
Any condition which reduces the number of nephrons or interferes with their function will result in kidney disease. Deprivation of adequate blood supply to the kidneys will interfere with the filtration process and myriads of cellular processes along these nephrons and as a result cause kidney dysfunction or kidney disease.
Infections and problems of the immune system will cause nephron loss. Some people are born with qualitative kidney dysfunction or reduced nephron mass and therefore prone to early kidney disease.
Generally the condition can be sudden and therefore referred to as acute kidney injury. Those that occur insidiously over months or years are referred to as chronic kidney disease. The conditions can be staged or graded depending on the severity or how kidney function has been affected.
The basic questions parents and care givers often ask is how do I know whether my child has kidney disease.
Except for the acute conditions which are often dramatic at presentation, there are no obvious signs or symptoms in the majority of cases. The acute kidney injury is usually sudden. There may be fluid loss as in diarrhoea, dysentery, burns or blood loss and others.
Our health system has developed adequate protocols to avoid acute kidney injury. There is, however, a very large scope for improvement.
Infections and infestations like malaria and post infectious kidney disease like acute post streptococcal glomerulonephritis cause acute injury by interfering with kidney functions. Some of these conditions cause direct damage others do so indirectly through stimulation of the immune system. In most cases of acute kidney injury, the outcome is very good. Dialysis may be required for a limited period of time. We must not forget drugs. These can cause great harm if the dosages are not adhered to. The latter and urinary tract infection can become chronic if not diagnosed and managed early.
The insidious or chronic kidney disease is an area where we need vigilance and awareness. The child may be perfectly well. They may come to the health care provider with very non specific symptoms. The following are some of the things which point to chronic kidney disease.
– Facial swelling in the morning which improves by the day.
– Headaches may present themselves as symptoms so are fits coma, tiredness, irritability, visual problems, facial palsy, heart failure, body swelling, and blood in the urine, taking too much water or passing lots of urine and bedwetting.
– Some children may come with vomiting, poor appetite, nausea, abdominal pain, weight loss or poor growth and rickets.
– Some may come with nose bleeding, skin paleness just to mention but a few.
In some situations there may be a sibling or a close relative with kidney disease. There may be a family member with deafness. In some cases there is a family member with a similar illness, diabetes or high blood pressure. These point to a genetic, familial or an inheritated kidney disease.
A lot has been achieved through our immunisation programmes. Hepatitis vaccination has reduced the burden of kidney disease associated with this infectious disease. Screening and treating for syphilis has resulted in a marked reduction of nephrotic syndrome at birth associated with this disease.
Currently efforts in Prevention of Mother to Child Transmission of HIV in pregnant women has seen a fall in cases of HIV children hence a markedly reduced HIV associated kidney disease. The difficult conditions are mentioned below.
The perinatal or congenital kidney disease needs to be detected early to have hope of life or normal growth and development. The pregnancy/amniotic fluid may be too much or too little. A baby’s urine contributes significantly to the amount of the amniotic fluid.
A baby in the womb with no kidneys results in less amniotic fluid. A baby producing too much poor quality urine because of malfunctioning of the kidney will have an abnormally large pregnancy fluid. A very large placenta to baby ratio in excess of 25 percent points to a kidney problem.
The advent of ultrasound scan has helped detect some of these problems. A lot of mothers in our country ask for a scan during pregnancy for the sex determination of the baby ignorant of the fact that a lot of anatomical and qualitative abnormalities can be detected during this procedure.
The anatomical abnormalities of the urinary tract with urine back flow can cause chronic kidney disease starting before birth. The latter predisposes the child to urinary tract infection after birth worsening the already existing problems. Children with multiple cysts can be detected this way early.
Urinary tract infection is an important cause of a gradual loss of kidney function as a result of scarring and loss of kidney filtration units. The predisposing factors to UTI are anatomical abnormalities of the Urinary Tract and female gender because of the short urethra. An aggressive investigation and treatment of urinary tract infection is the mainstay of management. This helps in preserving the finite filtration units at a level below which the child can be tipped into irreversible chronic kidney disease.
The majority of children we see in clinics have profuse protein loss in the urine. This condition is referred to as nephrotic syndrome. This might be secondary to some known disease condition in which case treating the cause may resolve the urine protein loss. Some conditions which are associated with this condition are HIV, Hepatitis, schistosomiasis, lymphomas, some drugs and connective tissue disorders to mention but a few.
The above is referred to a secondary nephrotic syndrome. In some cases there is no cause or association after exhaustive investigations. This is referred to as a primary type of nephrotic syndrome. We have in our armamentarium medicines which can retard the protein loss and slow the progressive destruction of kidney functional units thereby averting progression to chronic kidney disease.
There are however cases of primary nephrotic syndrome which,despite all treatment modalities, there is no response or variable response to treatment. For all nephrotic syndrome patients, they are easy to identify.
Usually they have a puffy face in the morning which gets better by the day. They pass frothy sometimes oily urine. A urine dipstix is usually the first step to diagnosis. These patients may or may not have high blood pressure.
There are a lot of treatments available if you are found to have a kidney disease. These depend on the type, stage and the degree of damage. These range from retarding progression of the disease process to dialysis and kidney transplantation. The latter two are more expensive and beyond the reach of the majority of our people. The best option available is prevention through awareness and screening.
We encourage children and other people this World Kidney Day to have their urine and blood pressure checked. This is more important if you have a condition most likely related to your kidneys as stated above or a family member with a kidney ailment. Pregnant women should ask for more information regarding the status of their unborn baby kidneys when asking for a scan.
PSMI has two renal units in Harare at Parkview and West End Hospitals which are manned by highly professional staff. The PSMI Parkview Haemodialysis Centre offers diagnostic and therapeutic services; for patients with progressive renal failure.
These include detection of any incipient renal disease in diabetic patients, for patients with difficulties controlling hypertension that is associated with renal insufficiency and for patients with renal and stone disease. Patients can visit these centres for screening of any kidney ailment.
*Dr L K Muchemwa is a Nephrologist at PSMI Parkview Haemodialysis Centre.