| BackgroundRegulating water metabolism is an important physiological process.Clinically,a number of patients are admitted to the hospital because of the symptoms of water metabolism disorder,such as polyuria,polydipsia and so on.In addition to identify some common diseases through laboratory tests such as diabetes,hypokalemia,hypercalcemia,chronic hypoadrenocorticism,etc.It is also important to think of diabetes insipidus(DI)and primary polydipsia.DI according to the pathogenesis can be divided into central diabetes insipidus(CDI),which is more common in clinic,diabetes insipidus during pregnancy and nephrogenic diabetes insipidus(NDI).The symptoms of CDI and primary polydipsia are similar,but the pathogenesis and treatment are different.Therefore,it is significant to clarify the differential diagnosis points,solve the problems in the diagnosis process,and put forward more perfect diagnosis and treatment methods,which are of great significance for guiding clinical work.ObjectiveTo explore the differential diagnosis and treatment of CDI and primary polydipsia,and reduce missed diagnosis and misdiagnosis rate.Materials and Methods1.The medical records of 31 cases of CDI and primary polydipsia were collected from the Shandong provincial hospital during 2008 to 2017,including gender,age,blood pressure,BMI,pituitary MRI,the biochemical indexes of water deprivation test and desmopressin administration if necessary,and other auxiliary examination results.The above cases were analyzed retrospectively.19 cases were diagnosed as CDI,2 cases of them were complete CDI,17 cases were partial CDI.12 cases were with primary polydipsia.2.To read the papers on CDI and primary polydipsia at home and abroad in recent years,and carefully screen them,combined with clinical cases,we analyzed the differential diagnosis process,treatment and prognosis.Results1.The average duration of symptoms,the average amount of drinking water,the average amount of urine,and the average urine specific gravity in the patients with polyuria and polydipsia before admission:The average duration of disease in 19 cases of CDI was(1.8±3.6)years.The average amount of drinking water before admission was(8.87±4.25)L,the average urine volume was(8.87±4.25)L,and the average urine specific gravity was(1.004 ±0.002).The average duration of 12 cases of primary polydipsia was(1.8±2.2)years,and the average drinking volume before admission was(5.83±2.41)L,the average urine volume was(5.83±2.41)L,and the average urine specific gravity was(1.007±0.035).2.The process and related data analysis of water deprivation test and desmopressin administration if necessary:After water deprivation test,12 cases were diagnosed as primary polydipsia whose urine specific gravity were greater than or equal to 1.020.The urine specific gravity of 19 cases were less than 1.020.Among them,2 cases who were diagnosed as complete CDI,had more plasma osmotic pressure than urinary osmotic pressure after water deprivation test,and urine osmotic pressure increased 96.4%and 218.8%after desmopressin administration,which were more than 50%.17 cases who were diagnosed as partial complete CDI,urine osmotic pressure were between 300-800 mOsm/L after water deprivation test,and the urine specific gravity of 12 cases of them was more than 1.020 after desmopressin administration,the urine osmotic pressure of 7 cases among them increased 10-50%.During the test,patients had no nausea,vomiting,dizziness,headache and other serious symptoms of dehydration.The numbers of urine specific gravity after platform and injecting vasopressin were tested by multiple related samples Friedman test and P<0.05(P=0.000).It means that the differences were statistically significant.3.Pituitary magnetic resonance imaging(MRI)results:19 cases of CDI who were diagnosed by water deprivation and desmopressin administration,including 2 cases of complete CDI patients(10.5%),pituitary gland enhanced MRI results of 1 cases of pituitary posterior lesions,considered Rathke's cleft cysts or craniopharyngioma;another 1 cases of pineal gland lesions,considered germ cell tumor.17 partial CDI patients(89.5%),high signal loss of posterior in 10 cases(1 cases with detailed history of head trauma,the rests were considered as idiopathic CDI),1 case of pituitary granuloma combined with Rathke's cleft cysts,1 case of pituitary adenoma,2 cases of germ cell tumor of pituitary,1 case was Sheehan syndrome with plasmocyte granuloma of skull,2 cases without pituitary enhanced MRI(including 1 case of craniopharyngioma after surgery).12 cases of primary polydipsia,9 cases underwent pituitary enhanced MRI.2 cases showed partial empty sella.5 cases showed high signal disappeared in posterior pituitary,2 cases had no abnormal in pituitary gland,3 cases had no pituitary enhanced MRI.4.Treatment and outcome:Among the 19 cases of CDI,16 patients were given oral desmopressin tablets,1 case partial CDI of pituitary granuloma combined with Rathke's cleft cysts were treated with oral desmopressin tablets and prednisone tablets.1 case was treated with hydrochlorothiazid,1 case partial CDI of germ cell tumors agreed to surgical treatment.18 cases of drug treatment improved significantly.14 cases of drug treated patients(4 cases with absence of data)at admission and discharge water volume of two related samples Wilcoxon test,P<0.05(P=0.001),the difference has statistical significance.12 cases of drug treated patients(6 cases with absence of data)at admission and discharge urine volume of two related samples Wilcoxon test,P<0.05(P=0.012).12 cases of primary polydipsia were given dietary guidance and psychological counseling.After detailed inquiries,the patients' symptoms were obviously improved.Conclusion1.Although the clinical symptoms of CDI and primary polydipsia were similar,the two were different in the water deprivation test and desmopressin administration if necessary.Patients with complete CDI,after the water deprivation test,urine osmotic pressure was less than 300 mOsm/L or urine osmotic pressure was less than plasma osmotic pressure and urine specific gravity was less than 1.020,urine osmotic pressure increased more than 50%after desmopressin administration.Patients with partial CDI after the water deprivation test,urine osmotic pressure was between 300-800 mOsm/L and urine specific gravity was less than 1.020.The urine osmotic pressure was more than or equal to 1.020 or urine osmotic pressure increased 10-50%.The urine specific gravity of primary polydipsia after water deprivation test can be more than 1.020,without desmopressin administration.2.Pituitary enhanced MRI can help to clarify the etiology of CDI,but CDI and primary polydipsia can not be distinguished.The water deprivation test and desmopressin administration are the gold standard for diagnosing CDI and primary polydipsia. |
PDF Full Text Request