Humans are indeed a marvel creature. Humans are developed with many cells and organs that work as systems. These body systems enable humans to live and survive in many conditions or environments. Changes in the body often precipitate as symptoms and some symptoms give signs that there is something wrong in the body. In this DoctorOnCall’s article, we will be learning about anuria as a symptom.
Anuria will have connection with the urinary system. Before we go through what anuria is and its causes, knowing a little more of the normal urinary system can help us understand what anuria is. The bladder system is a function to filter blood and produce urine as the body waste. The urinary system helps to maintain balance fluid and salt or electrolytes such as potassium and sodium in blood. It also plays a role in maintaining blood pressure. It consists of kidney, ureter, bladder and urethra. A normal urine indicates a person is having a healthy urinary system.
Back to our main focus, anuria is the absence of urine production or minimal urine output. It is defined as urine output of fewer than 100 millilitres per day. Healthy adults produced between 800 to 2000 millilitres of urine in a day. Anuria should be confused with oliguria. Oliguria occurs when urine produced is fewer than 500 millilitres per day. It is worth noting that the normal urine output or urine produced depends on the age of a person and slight changes may occur when a person’s hydration level is compromised. For example, oliguria in adults is considered when the urine output is below 100 millilitres per day whereas in children it is less than 0.5 millilitres per kilogram of the body weight in an hour (<0.5 mL/kg/hour) for 24 hours. It is worth noting that healthy newborns may have no urine output for 24 hours after birth.
There are many causes that could lead to anuria. One thing for sure, anuria is usually seen when the kidney stops producing urine or there is a blockage that prevents the urine from the kidney to flow. Common causes of anuria include kidney failure that cause kidney to stop functioning, kidney stones that cause blockage in the kidney or the ureter, growth or tumour near the kidney causing blockage of the urine outflow and metabolic disease such as diabetes or high blood pressure (hypertension) that damage the blood vessels in the kidney. Aside from kidney function being hindered or disturbed, heart failure, liver disease, heavy infections such as sepsis, severe burns or major haemorrhage may cause anuria as a result of the reduced blood flow to the kidney.
Anuria itself is not a condition but is a symptom or signs of an underlying medical condition. The many causes behind anuria should be considered as serious issues and people who have anuria need to get medical advice immediately. Anuria usually does not present on its own as it is often accompanied with other symptoms depending on the underlying medical conditions. For instance, individuals with severe dehydration may be presented with anuria and have symptoms such as fast heartbeat, low blood pressure and reduced skin elasticity (turgor). Since anuria is so often caused by serious medical issues or problems that can be life-threatening, it is best for those with anuria to seek a doctor and to find the cause leading to anuria.
Anuria is usually diagnosed by measuring a person’s urine output. This is usually done via a urinary catheter. Urinary catheter is a soft tube placed through the vagina or penis and drains urine that usually resides in the bladder. Additional testing such as blood testing, kidney function, urine test and imaging test may be done to help find the cause of anuria. In some cases, biopsy procedures of taking small samples of the kidney tissue may be performed.
Treatments are emphasised on treating the cause of the anuria. Removal of urinary obstruction, renal replacement therapy and medications to treat its causes are among the common treatments given for anuria. It is vital to restore the normal urine output as it can lead to life-threatening diseases when it is left untreated. Health problems underlying the anuria can also pose great danger when it is not identified and addressed promptly. Anuria itself can cause kidney damages or failure and these may be permanent.
It can be concluded that anuria can be caused by many causes. The very low urine output to no urine at all should indicate a person is experiencing anuria. Since the severity of anuria itself along with its underlying health conditions vary greatly, it is best to see a doctor whenever there is significant change in urine output. The outcome of anuria depends on its causes, how quickly it is diagnosed and treated, and the person’s health status or other health history themselves. Aside from treatments given by doctors, patients with anuria should engage in an active lifestyle and practise healthy eating habits.