Clinical diagnostic thought process of DD hematuria
Renal diseases have many clinical manifestations, and one clinical manifestation can be seen in many diseases. During clinical teaching, in order for students to master the clinical diagnostic procedures of renal diseases, renal diseases are categorized into 10 syndromes such as nephritis syndrome, nephrotic syndrome, hematuria syndrome, acute renal failure syndrome, chronic renal failure syndrome, urinary frequency-dysuria syndrome, urinary stone syndrome, and tubulointerstitial disease syndrome. Now we introduce the clinical diagnostic thinking procedure for hematuria syndrome.
Step 1 Is it true hematuria
(1) Fleshly hematuria is light red or washed water-like, but not necessarily red urine is hematuria, such as myoglobinuria, paroxysmal sleep hemoglobinuria, hematoporphyria urine dark red (coffee color), certain foods (beets, tomato leaves, pigment) can make urine red, certain drugs (rifampin, dalantin, phenothiazine, etc.) can make urine red, but not hematuria, the identification method is urine microscopy without RBC. (2) Fake Hematuria, some people intentionally mix blood into the urine in order to achieve certain purposes, the identification method pay attention to the retention of urine specimens. Contaminated hematuria, women with menstruation or hemorrhoid blood mixed into the urine specimen, so the patient with hematuria should be checked for hemorrhoids, and women with hematuria must pay attention to ask whether it is during menstruation. ④ Transient hematuria, such as strenuous exercise, fever, pollen, chemicals or drugs (such as cyclophosphamide) can also occur as transient hematuria, only 1-2 times detected with RBCs in the urine, but repeatedly rechecked as negative, often without significant meaning and not the scope we want to discuss. All of the above are not true hematuria, only urine centrifugal sediment RBC ≥ 3 / HP, or bovine packet wah count disc count RBC ≥ 8000 / ml, or urinary RBC excretion rate ≥ 100,000 per hour is true hematuria, some part of true hematuria is a signal of serious kidney disease, to be examined according to the following methods, with a view to a clear diagnosis.
Step 2: Is it glomerular hematuria? Or non-glomerular hematuria?
After determining whether it is true hematuria, it is important to first distinguish between glomerular and non-glomerular hematuria, which is very important for clinical selection of the next step of examination. If it is glomerular hematuria, there is no need to do intravenous pyelogram, cystoscopy, retrograde angiography, CT, MRI and other examinations, which not only have no clinical significance but also bring unnecessary pain and economic burden to the patient or even delay the delayed diagnosis. In case of non-glomerular hematuria, kidney biopsy will also bring unnecessary pain and economic burden to the patient. Therefore, it is necessary to distinguish glomerular hematuria from non-glomerular hematuria in patients with true clinical hematuria, and then select the appropriate tests to clarify the diagnosis.
The following methods can distinguish glomerular hematuria from non-glomerular hematuria.
1, red blood cell morphology and count: urine red blood cells are unequal in size, appearance is aberrant such as aubergine ≥ 75%, red blood cell count ≥ 8000 / ml, it is glomerular hematuria, indicating that red blood cells through the glomerular basement membrane renal tubules of the concentration of red blood cells deformation. However, a small amount of red blood cells seen in normal individuals is not pathological hematuria even if the urinary deformed red blood cells are ≥75% and the urinary red blood cell count is ≤8000 cells/ml. If the red blood cell count is ≥8000/ml and the urinary normal red blood cells are ≥75% or more, it is non-glomerular hematuria, indicating that the hematuria comes from the renal pelvis, renal calyces, ureter, bladder and urethra, and is non-glomerular hematuria.
2.Average volume of red blood cells: Since the volume of deformed red blood cells is smaller than normal red blood cells, fresh urine specimens are measured and traced with Coulter calculation analyzer for average volume and distribution curve of red blood cells. If the mean volume is <72fl and the distribution curve is small cellular, the hematuria is from the glomerulus.
3, urine protein and tubular: If hematuria is accompanied by proteinuria, the source of hematuria can be judged according to the amount of proteinuria. hematuria patients can release hemoglobin from the volume of red blood cells in the urine and can have mild proteinuria, but generally not more than 1.0 g for 24 h. Some studies have shown that carnal hematuria with or microscopic hematuria with proteinuria ≥ 1.0 g/24 h is mostly glomerular hematuria, and if it is accompanied by a large amount of proteinuria. The possibility of glomerulonephritis is even higher. If the hematuria is accompanied by red blood cell tube type and granular tube type, it is more likely to be glomerular hematuria.
4.Whether it is accompanied by swelling: generalized swelling can be seen in cardiogenic, hepatic, endocrine, dystrophic, and renal edema. Renal edema is for glomerular disease. Non-glomerular kidney disease generally does not have edema when renal function is normal, although non-glomerular diseases such as pyelonephritis can also have edema at a later stage, indicating that it also involves the glomerulus in renal failure. If a patient with hematuria has normal kidney function along with swelling, it can be affirmed as glomerular hematuria.
Step 3: The underlying disease of hematuria
Glomerular hematuria , can be sure that it is not renal tuberculosis, tumors of the kidney, stones of the urinary system, infection of the urinary system and renal vascular lesions, there is no need to do cystoscopy, retrograde pyelogram, intravenous pyelogram, CT, MRI and other examinations to first exclude secondary glomerular diseases are lupus nephritis, purpura nephritis, hereditary nephritis nodular arteritis, infective endocarditis, Goodpasture syndrome, etc.
(1) Lupus nephritis: young women with glomerular hematuria with the following features are highly considered lupus nephritis: (1) unexplained prolonged fever; (2) multiple arthropathies; (3) skin damage such as facial butterfly erythema or generalized discoid erythema; (4) multi-organ and multi-system damage; (5) tendency to spontaneous remission and exacerbation; (6) effective hormones and cytotoxic agents; (7) increased hemoprotein electrophoresis gamma globulin; (8) rapid hematocrit; (9) hair loss. . The diagnosis was made with reference to the 11 diagnostic criteria for systemic lupus erythematosus revised by the American College of Rheumatology in 1982, and four of them were met. A renal biopsy is also performed to clarify the pathological type in order to guide treatment and determine the prognosis.
(2) Purpura nephritis: This disease is mostly found in children. In addition to hematuria, proteinuria, swelling, hypertension, and renal function impairment are also seen in heavy kidney cases. There is hemorrhagic symmetrical purpura, half of the patients have wandering joint pain, abdominal pain, etc. can be differentiated. Renal biopsy can help in the diagnosis.
(3) Benign familial hematuria, a kind of basement membrane nephropathy, is an autosomal dominant disease, and a few of them show autosomal recessive inheritance, and the diagnosis depends on renal biopsy, and the characteristic lesion under electron microscopy is a marked thinning of the glomerular basement membrane with a thickness of about 235-327 nm.
(4) Hereditary nephritis: It is a monogenic genetic disease in which the patient is heterozygous, with a male predilection, and a clinical tendency to progressive hearing and vision loss (conical and spherical crystals) and a family tendency to hereditary nephritis is highly suspected.
(5) Polyarteritis nodosa: the disease can invade the small and medium-sized arteries throughout the body, causing necrotizing vasculitis, small veins can also be involved, renal damage in addition to hematuria, proteinuria and even nephrotic syndrome, hypertension, severe cases of renal hypofunction, extra-renal manifestations can be fever, malaise, weight loss, myalgia and arthralgia, followed by other organ involvement, polymorphic, such as dermatitis, hemorrhagic spots, reticulocutaneous cyanosis. Ischemic necrosis and subcutaneous nodules, as well as gastrointestinal and neurological damage. Positive anti-neutrophil cytoplasmic antibodies (ANCA) and significant increase in blood sedimentation, combined with clinical manifestations and biopsy, can clarify the diagnosis.
(6) Mixed connective tissue disease: Several connective tissue diseases overlap in the same patient, such as scleroderma and dermatomyositis, scleroderma and rheumatoid arthritis, scleroderma and systemic lupus erythematosus, and rheumatoid arthritis and systemic lupus erythematosus. If both diseases can be diagnosed independently, they are called overlapping syndromes. If one disease can be diagnosed independently and the other does not fully meet the diagnostic criteria, it is called mixed connective tissue disease.
If secondary diseases such as the above are excluded, primary glomerular disease can be identified. Primary glomerular disease can be seen as acute glomerulonephritis, chronic glomerulonephritis, acute progressive glomerulonephritis, and cryptogenic glomerulonephritis. Pathological types are mostly seen in IgA nephropathy, thylakoid proliferative nephritis, and also membranoproliferative nephritis with focal segmental sclerosis.
If it is non-glomerular hematuria, there is no need to go for renal biopsy. Abdominal plain film, intravenous pyelogram, ultrasound, CT, cystoscopy and retrograde pyelogram, renal arteriogram, urine cytology should be done to clarify one of the following diseases
1.Renal vascular and tubular interstitial diseases
(1) Allergic disease: acute allergic interstitial nephritis.
(2) Infectious diseases: acute pyelonephritis, renal tuberculosis.
(3) Genetic diseases: polycystic kidney, spongy kidney.
(4) Vascular diseases: malignant hypertension, renal artery embolism, lumbago-hematuria syndrome, arteriovenous malformation
(5) renal papillary necrosis, diabetes mellitus, painkiller nephritis.
2.Urinary tract diseases
(1) Renal pelvis: migratory cell carcinoma, vascular varices, stones, injury.
(2)Ureter: stone, tumor, tuberculosis, periureteral inflammation, arteriovenous varicose.
(3) Bladder: bladder cancer, cystitis (bacterial, tuberculosis, viral, parasitic and fungal), stone injury, chronic interstitial cystitis, vascular abnormalities, amyloidosis, motility hematuria, cyclophosphamide-induced cystitis, radiation and allergic cystitis.
(4) Prostate: acute and chronic prostatitis, prostate cancer, and benign prostatic hyperplasia.
(5) Urethra: acute and chronic urethritis, trauma, vascular abnormalities, tumors, urethral ulcers, etc.
3, abnormal coagulation diseases
(1) Platelet abnormalities: idiopathic or pharmacologic thrombocytopenia
(2) Defects in coagulation factors: hemophilia, necrotizing disease, heparin or warfarin therapy, hereditary capillary dilatation and other primary or acquired coagulation defects.
The following disorders are suggested by age, medical history, physical examination, and laboratory tests
In adolescents, hematuria is characterized by infectious diseases of the urinary tract, glomerular disease is common, and congenital urinary tract abnormalities are also seen; in middle-aged patients, urinary tract infections, stones and bladder tumors are common; men between the ages of 40 and 60 should be alert for bladder tumors, kidney or ureteral tumors. In women, urinary tract infections and stones are common; in men over 60 years of age, enlarged prostate, prostate cancer and urinary tract infections are common. In women, urinary tract infections, kidney or bladder tumors are common.
Symptoms and physical symptoms.
(1) Weight loss: tumors, tuberculosis.
(2) Weight gain: nephritis, renal syndrome.
(3) Fever or urinary tract irritation baffled: urinary tract infection
(4) renal colic, back pain: stones, back pain and hematuria syndrome, renal vein thrombosis.
(5)Arthralgia, skin rash: SLE, purpura nephritis.
(6) Hearing and vision abnormalities: hereditary nephritis.
(7) Hemoptysis: pulmonary hemorrhagic nephritis syndrome.
(8) Tinnitus: vasculitis.
(9) New throat and skin infection: streptococcal infectious nephritis.
(10) Fever and heart murmur: infective endocarditis.
(11) History of useful CTX and other medications: hemorrhagic cystitis.
Through the above lectures, students mastered the concepts of glomerular and non-glomerular hematuria, clinical examination procedures and main diseases considered, reducing blindness and improving the understanding of hematuria.