I. Concept Hyperchloremic metabolic acidosis caused by single renal tubular hydrogen secretion dysfunction (absolute or relative deficiency of hydrogen secretion). II. Classification (i) Distal tubular acidosis (ii) Proximal tubular acidosis (iii) Mixed tubular acidosis (iv) Hyperkalemic tubular acidosis III. Clinical and laboratory characteristics and etiology (I) Type I 1. Common in young and middle-aged women. 2, hyperchloremic metabolic acidosis 3, hypokalemia, muscle weakness muscle paralysis; polyuria, annoying drinking. 4, arrhythmia with ECG abnormalities, may have hyponatremia with dehydration fever. 5, low blood calcium, low blood phosphorus rickets, bone thinning, pathological fractures, deformities. 6, high urinary calcium stones, secondary infection, obstructive nephropathy, renal calcification, renal insufficiency. 7, urinary pH >6.0, morning urine pH often >5.5 8, decreased urinary ammonium and TA 9, other tubular proteinuria; deafness, myopathy (hereditary); early normal CFR. 10, clinical typing Complete type; incomplete type (II) Type II 1, male infants or children more. 2, hyperchloremic metabolic acidosis. 3.Low blood sodium, polyuria, dehydration fever 4.Low blood potassium Weakness, muscle paralysis; polyuria; irritability; cardiac arrhythmia. 5, urinary bicarbonate excretion fraction > 15% 6, urinary pH > 5.5 or urinary pH < 5.5 7, glycosuria, amino aciduria, hyperphosphaturia, hyperuricuria, growth retardation 8, clinical typing monotypic, complex (III) type III (IV) type IV 1, elderly, often with certain chronic kidney disease or adrenal gland disease. 2, hyperchloremic metabolic acidosis, not equivalent to renal insufficiency. 3, Reduced GFR above or below 20 ml/min. 4.Hyperkalemia. 5, Hypoaldosteronism or hyporenin hypoaldosteronism 6, Decreased urinary NH4Cl with TA. 7, urinary pH >5.5 (sodium-dependent) or <5.5 (non-sodium-dependent, hypoaldosteronism type). 8, can be complicated by salt loss nephropathy. 9. Clinical typing: sodium-dependent, hypoaldosteronism and aldosteronism non-responsive type IV. Diagnosis (I) Diagnostic clues 1. History 2. 2.Type II NaCO3 reabsorption test: FE-H CO3 >15% 3.Type III Positive NH4Cl test, FE-H CO3=5-15%. 4. Type IV hyperkalemic hyperchloremic metabolic acidosis + renin angiotensin aldosterone assay. V. Differential diagnosis and diagnostic flux VI. Laboratory tests (a) tests related to the acidification function of the renal tubules 1. ammonium chloride test 2. urinary titratable acid and urinary ammonium assay 3. urinary anion gap assay (b) differentiation tests for each subtype of type I renal tubular acidosis (c) acidification function test of the proximal renal tubules VII. treatment (a) etiology and causative therapy Type I prohibits acidogenic salt drugs; Type II prohibits carbonic anhydrase inhibitors The type IV prohibits potassium storage drugs such as Ativan, aminopterin and renal angiotensin converting enzyme inhibitors. (B) symptomatic treatment 1, alkaline agents to correct acidosis 2, supplementation of the lack of ions 3, vitamin D 4, functional diuretics 5, salt corticosteroid replacement therapy