Light blood after urinating

Adult women have their period every month, and vaginal bleeding for a few days is normal. However, vaginal bleeding outside of the menstrual period will give female friends a headache, because this is abnormal bleeding, and there is definitely a problem. Female friends will wipe with paper towels every time after going to the toilet to maintain hygiene. Some women find that there is a faint blood stain when wiping after urinating. What is the reason for this?

1. Kidney and urinary tract diseases

(1) Inflammation: acute and chronic glomerulonephritis, acute and chronic pyelonephritis, acute cystitis, urethritis, urinary tract tuberculosis, urinary tract fungal infection, etc.

(2) Stones

Stones in any part of the renal pelvis, ureter, bladder, or urethra can scratch the urothelium when they move, which can easily cause hematuria and secondary infection. Large stones can cause urinary tract obstruction and even renal damage.

(3) Tumors Malignant tumors in any part of the urinary system or in adjacent organs that invade the urinary tract can cause hematuria.

(4) Trauma refers to violent injury to the urinary system.

(5) Congenital malformations

Polycystic kidney disease, congenitally ultra-thin glomerular basement membrane, nephritis, and the nutcracker phenomenon (this disease is caused by congenital vascular malformations that lead to compression of the left renal vein running between the abdominal aorta and the superior mesenteric artery, causing persistent microscopic hematuria. The right renal vein is directly injected into the inferior vena cava, while the left renal vein must pass through the angle formed by the abdominal aorta and the superior mesenteric artery to be injected into the inferior vena cava. Normally, this angle is 45° to 60°. If this angle is congenitally too small or is filled with mesenteric fat, enlarged lymph nodes, or peritoneum, it can cause the nutcracker phenomenon. Diagnosis is mainly based on CT, B-ultrasound, and renal venography. Treatment requires surgical correction).

2. Systemic diseases

(1) Hemorrhagic diseases: thrombocytopenic purpura, allergic purpura, hemophilia, leukemia, malignant histiocytosis, aplastic anemia, etc.

(2) Connective tissue diseases: systemic lupus erythematosus, dermatomyositis, polyarteritis nodosa, scleroderma, etc.

(3) Infectious diseases: leptospirosis, hemorrhagic fever, filariasis, infectious bacterial endocarditis, scarlet fever, etc.

(4) Cardiovascular diseases: congestive heart failure, renal embolism, and renal vein thrombosis.

(5) Endocrine and metabolic diseases: gouty kidney, diabetic nephropathy, and hyperparathyroidism.

(6) Physical and chemical factors such as food allergies, radiation exposure, drugs (such as sulfonamide, phenol, mercury, lead, arsenic poisoning, large-scale infusion of mannitol, glycerol, etc.), poisons, and after exercise. 3. Diseases of adjacent organs Tumors of the uterus, vagina or rectum invade the urinary tract.

1. Changes in urine color

The main manifestation of hematuria is a change in urine color. Except for microscopic hematuria which has normal color, macroscopic hematuria will appear in different colors depending on the amount of bleeding. The urine is light red like meat washing water, indicating that the blood content per liter of urine exceeds 1 mL. If bleeding is severe, the urine may appear bloody. When the kidneys are bleeding, the urine is mixed with blood evenly and the urine is dark red; when the bladder or prostate is bleeding, the urine is bright red and sometimes contains blood clots.

2. Abnormal segmented urine

Divide the entire urine into segments and observe their colors, such as the three-cup urine test, in which three clean glass cups are used to collect the initial, middle and terminal urine for observation. Hematuria in the initial segment indicates that the lesion is in the urethra; hematuria in the terminal segment indicates that the bleeding site is in the bladder neck, trigone or posterior urethra, prostate and seminal vesicles; if all three segments of urine are red, it means that the entire urine is hematuria, indicating that the hematuria comes from the kidneys or ureters.

3. Renal or postrenal hematuria

Microscopic hematuria is normal in color, but microscopic examination can confirm the hematuria and determine whether it is renal or postrenal. Microscopic red blood cells of varying sizes and shapes indicate glomerular hematuria, which is seen in glomerulonephritis.

Patients with hematuria may also have systemic or local symptoms. The main symptoms are urinary system symptoms. If accompanied by dull pain or colic in the kidney area, it indicates that the lesion is in the kidney. Bladder and urethra diseases often cause frequent urination, urgency and difficulty urinating.

5. Asymptomatic hematuria Some patients have hematuria with neither urinary tract symptoms nor systemic symptoms. It is seen in the early stages of certain diseases, such as renal tuberculosis, kidney cancer or early bladder cancer.

6. Associated symptoms

① Hematuria with renal colic is a characteristic of renal or ureteral stones; ② Hematuria with interrupted urine flow is seen in bladder and urethral stones; ③ Hematuria with thin urine flow and difficulty urinating is seen in prostatitis and prostate cancer; ④ Hematuria with frequent urination, urgency and pain is seen in cystitis and urethritis, and is accompanied by low back pain. High fever and chills are often pyelonephritis; ⑤ Hematuria with edema, hypertension, and proteinuria is seen in glomerulonephritis; ⑥ Hematuria with renal mass, unilateral can be seen in tumors, hydronephrosis and renal cysts; bilateral enlargement is seen in congenital polycystic kidney, and touching mobile kidneys is seen in renal ptosis or wandering kidney; ⑦ Hematuria with bleeding in the skin, mucous membranes and other parts is seen in blood diseases and certain infectious diseases; ⑧ Hematuria combined with chyluria is seen in filariasis and chronic pyelonephritis.