Pediatric Antidiuretic Hormone Syndrome
Introduction
Introduction to pediatric antidiuretic hormone abnormal syndrome Syndromeofinappropriateantidiuretichormonesecretion (SIADH) means that when plasma osmolality, normal or low blood sodium, vasopressin is still secreted, resulting in reduced free water clearance, water retention, hyponatremia, low permeability A syndrome that suppresses a series of clinical manifestations such as blood pressure. basic knowledge The proportion of sickness: 0.0001% - 0.0002% Susceptible people: children Mode of infection: non-infectious Complications: hyponatremia, coma
Cause
The cause of pediatric antidiuretic hormone abnormality syndrome
(1) Causes of the disease
The cause of SIADH may be increased secretion of non-endocrine atopic ADH, or ADH regulatory dysfunction, such as lung disease (pneumonia, tuberculosis, asthma persistent state); central nervous system diseases (meningitis, encephalitis, brain abscess, brain Tumors, brain trauma, acute infectious radiculitis, subarachnoid hemorrhage and cerebrovascular disease can produce ADH-like substances. In addition, during hypoxemia, the cardiac output decreases, which can also stimulate the secretion of ADH. Malignant tumors such as lung cancer, duodenal cancer, pancreatic cancer, prostate cancer, thymic cancer, etc. These tumor cells can produce ADH, which is a heterologous hormone secreting tumor. This condition is rare in children, and some drugs such as chlorpropamide Vincristine, clofibrate (clofibrate) and thiazides can increase renal tubular sensitivity to ADH or to neurons in the hypothalamus, increasing ADH secretion, as well as SIADH, neonatal asphyxia, Intracranial hemorrhage can cause this disease.
(two) pathogenesis
Due to increased secretion of ADH, renal tubular absorption of water, body water retention, increased body fluid volume and dilute hyponatremia, in order to maintain intracellular and extracellular osmotic pressure balance, water enters the cell, causing intracellular edema, especially brain cell edema is more obvious The disease has low blood sodium, but high urinary sodium, high osmotic urinary pressure, and urinary osmotic pressure exceeds blood osmotic pressure. The cause of high urinary sodium is related to the reduction of sodium absorption by the renal tubule and the inhibition of aldosterone secretion. It is also associated with an increase in sodium-sparing factors and prostaglandins.
Prevention
Prevention of urinary hormone secretion abnormal syndrome in children
The most important thing for SIADH is prevention, alerting to SIADH caused by drugs, doing vaccination work, preventing brain, encephalitis, brain trauma, preventing neonatal asphyxia, intracranial hemorrhage, etc., all of which are beneficial for reducing the incidence of this disease.
Complication
Pediatric antidiuretic hormone secretion syndrome complications Complications, hyponatremia, coma
Due to excessive reabsorption of kidney water, water retention, fluid volume is too large, resulting in water poisoning and hyponatremia, plasma osmotic pressure is reduced, while hypertonic urine and urinary sodium excretion are increased; hyponatremia can occur Convulsions, coma to death, persistent hyponatremia can cause irreversible brain damage.
Symptom
Pediatric antidiuretic hormone abnormal syndrome symptoms Common symptoms Loss of appetite, nausea, hyponatremia, coma, convulsions, antidiuretic hormone (A...
In addition to the primary disease manifestations, SIADH children are parallel with the degree of hyponatremia. When serum sodium is above 120mmol/L, the clinical symptoms are asymptomatic. When the blood sodium drops below 120mmol/L, there may be loss of appetite and nausea. Symptoms such as vomiting, when the blood sodium is lower than 110mmol / L, neuropsychiatric symptoms, even convulsions, coma until death, when the blood sodium is lower than 95 ~ 109mmol / L, for 3 days can cause irreversible brain damage, it appears When hyponatremia occurs, it should be corrected in time.
Examine
Examination of abnormal antidiuretic hormone secretion syndrome in children
1. Plasma osmotic pressure: decreased with the decrease of blood sodium, more <270mOsm / (kg · H2O).
2. Blood sodium and urine sodium: In the case of blood sodium <125mmol / L, urine sodium > 20mmol / L, up to 80mmol / L or more, urine osmotic pressure increased.
3. Other: serum chloride and BUN are slightly reduced.
X-ray chest X-ray, brain CT, electrocardiogram, etc. must be performed.
Diagnosis
Diagnosis and diagnosis of abnormal antidiuretic hormone secretion syndrome in children
The diagnostic criteria are as follows:
1. History: There is a history of primary disease or medication.
2. Clinical manifestations: symptoms of hyponatremia.
3. Urine sodium: high content, often >20mmol/L, low blood sodium <110mmol/L, even up to 80mmol/L.
4. ADH in blood and urine is higher than normal.
5. Renal function and adrenal cortical function are normal.
Differential diagnosis
SIADH should be differentiated from other causes of hyponatremia, such as kidney disease, hyponatremia caused by liver and heart disease, in addition to disease-related symptoms, edema, aldosterone, and urinary sodium.
Chronic adrenal insufficiency caused by hyponatremia and hyperuric sodium, clinical features of skin pigmentation, can be identified by urine and blood cortisol assay.
