Why do patients with nephritis suffer from lower back pain? What causes it?

Low back pain is a common and typical symptom of nephritis patients. Many nephritis patients will have low back pain in addition to symptoms such as proteinuria and hematuria. So why do nephritis patients have low back pain?

What is the cause of low back pain in patients with nephritis?

If you sprain your waist, strain your lumbar muscles, and experience low back pain, it is normal. If a normal person experiences back pain after strenuous exercise or heavy physical labor, especially after continuous weight bearing on the waist, it is not a serious matter and will be fine after a few days of rest. However, some people, especially young people, who do not participate in labor or sports and have no history of lumbar sprain, have symptoms of fatigue, oliguria, and soreness in the waist and knees, especially vague soreness in the lumbar area. If you look in the mirror again, you will find that your eyelids are slightly swollen and your face looks like you have not woken up yet. You must be extra vigilant at this time. These symptoms are early signs of nephritis. You should go to the hospital in time for a detailed examination and a routine urine test. If conditions permit, it is best to do a urine protein gel electrophoresis test, otherwise it will delay diagnosis and treatment and the consequences will be extremely serious.

So, why does kidney disease and nephritis cause back pain?

This is not just because the kidneys themselves are located in the waist. It turns out that kidney disease is an immune allergic reaction with a unique onset. It can occur suddenly or gradually. Nephritis often occurs in people who appear to be asymptomatic and have no history of kidney disease but have low immunity, such as those who have had colds, tonsillitis, mumps, and allergic rhinitis. The main cause of this disease is that after foreign bacteria, viruses, etc. invade the human upper respiratory tract, the body produces specific anti-kidney antibodies. If the pathogen invades the body again, the anti-kidney antibodies hidden in the blood will "bite" it tightly, forming a larger antigen-antibody complex, which is then transported to the kidneys by the blood and prepared to be excreted from the body. The bad thing is that the pores on the glomerular basement membrane are too small to filter out the large antigen-antibody complexes into the urine, so they accumulate there. However, the body's other defense force, the complement system, cannot tolerate these uninvited guests and launches a destructive attack on them. As a result, tissues such as the glomerular basement membrane are also damaged, causing the filtration membrane to rupture, and a large amount of protein in the plasma that has not yet been transformed and utilized by the body leaks out and is excreted in the urine, causing proteinuria.

Protein is one of the most important energy sources for life activities. The renewal, metabolism and function of all tissues and organs in the body require a certain quantity and quality of protein. The muscles in the waist and back directly control the human body's standing, walking, sitting, bending and other movements. Once these muscle groups lack sufficient protein supply, they will quickly show a tendency to "hunger", which is manifested as the muscle tissue mainly in the waist and legs losing its original tension, and the waist movement is significantly restricted, accompanied by symptoms such as heaviness, swelling and soreness.