Lower limb or circumferential flaccid paralysis is a symptom in the water and salt metabolism disorder type of Barth syndrome. The clinical manifestations of this disease are diverse, and the clinical types vary. The following are the examination items for lower limb or peripheral flaccid palsy: Examination items: urinary routine, urinary potassium (K+,K), intravenous pyelogram, electrocardiogram. The examination mostly sees increased urinary potassium and chloride excretion, increased urinary pH, decreased urinary specific gravity, blood AⅡ, AⅠ and ALD are significantly increased. Should routinely check the blood magnesium, low blood magnesium should be supplemented with magnesium at the same time as potassium. Laboratory examination 1, blood potassium, sodium, chloride more than the normal level. 2, blood pH can be higher than 7.46 alkalemia, C02CP is higher than 30mmol/L or more. 3.Plasma renin activity (PRA) may be increased up to (4.5±2.9) μg/L-h or more. 4.Blood Aldosterone (Aldo) value can be increased up to 101±9ng/L. 5.Blood PGA, PGE, PGF, PGI can be increased, such as PGF can reach (138.0±78.0) ng/ml. 6.Angiotensin II (Ang II) can be increased up to (95.8±35.2) ng/L. 7.Renal function test BUN can be increased up to 7.0mmol /The specific gravity of Mawson’s test is low, the amount of nocturnal urine is increased, and protein and red and white blood cells can be found in the urine. 8.Late stage of renal hypofunction may find lower blood calcium, higher blood phosphorus, higher AKP, higher uric acid, higher creatinine, higher PTH, and secondary hyperparathyroidism. 9. Urinary 17-OHCS and urinary 17-KS are mostly in the normal range. Imaging tests 1. Intravenous pyelogram may reveal renal stones, hydronephrosis and other abnormalities. 2.Electrocardiogram may reveal hypokalemia. 3.Nephrogram is abnormal. Renal biopsy may reveal hyperplasia and hypertrophy of the paraglomerular apparatus. 95% of renin is secreted by paraglomerular cells, and 1% to 5% may be produced by paraglomerular cells, interstitial cells, or endothelial cells of the small arteries of the bulb.