Jul 16, 2018
Hypercalcemiais a polyetiological pathology that is observed as a symptomatic complex of other diseases or an independent nosological form, based on a sharp or moderate increase in serum calcium concentration.
Due to the fact that this pathological condition belongs to the category of clinico-laboratory changes, the blood tests for the level of calcium saturation, as well as instrumental imaging methods( ray diagnostic methods) are on the foreground as diagnostic measures.
The clinical picture of this pathology has a direct relationship with the degree of increase in calcium concentration and the age of the patient. The basis of therapeutic measures of hypercalcemia includes stimulation of calcium excretion from the body by conservative methods, as well as prevention of possible bone resorption.
Causes of hypercalcemia
The main link in the etiopathogenesis of hypercalcemia is the excessive destruction of the structure of bone tissue of one or another localization that can occur in various pathologies( osteoclastic type of metastasis, thyroid pathologies with severe hyperthyroidism, malignant neoplasms with concomitant humoral hypercalcemia, prolonged immobilization, hypocalciuric hypercalcemia, Hypervitaminosis of groups D and A).
Another common mechanism for the development of hypercalcemia is an increase in the absorption of calcium in the jejunum, which is observed in milk and alkaline syndrome and sarcoidosis. Also, this mechanism of hypercalcemia is observed in patients taking long-term medicines containing calcium( antacids in diseases of the gastroenterological profile).
In addition to the above factors, the functioning of the urinary system is of great importance in the development of hypercalcemia. When the excretory process is inhibited, a calcium retention in the blood is observed.
Symptoms and signs of hypercalcemia
Initially, hypercalcemia is characterized by latent flow, in which the patient does not have any painful sensations or the symptoms are so unspecific that the patient can not recognize the cause of their occurrence. At this stage, this disease should be attributed to the category of random findings when conducting a screening laboratory examination of the patient.
To a greater extent, patients suffering from hypercalcemia of varying severity complain of various dyspeptic disorders( nausea, lack of appetite, heartburn).During the unfolded clinical picture, hypercalcemia manifests itself as symptoms of intestinal obstruction( prolonged constipation, flatulence, spastic pain syndrome in the projection of the abdominal cavity without clear localization).Due to the available reversible changes in renal concentrating mechanisms, the patient may experience polydipsia, nocturia and polyuria, which are of a transient, transient nature.
In a situation where the patient has hypercalcemia with a significant increase in calcium concentration in the body, severe clinical symptoms develop, which requires urgent medical intervention. The patient becomes emotionally labile, and in a far-advanced stage, various degrees of impairment of consciousness from somnobulence to coma are noted. The patient is disturbed by generalized muscle weakness, inability to perform the usual physical activity, however, convulsive syndrome with this pathology is extremely rare.
Prolonged hypercalcemia is always accompanied by transient or chronic renal failure due to the formation of many microcalcinates in the thickness of the renal parenchyma. It should be remembered that the violation of the urinary function of the kidneys provokes the development of a persistent malignant hypertension in a patient with hypercalcemia, which in some cases is the only clinical manifestation of this disease.
If hypercalcemia occurs against a background of hyperparathyroidism, the patient has a tendency to develop peptic ulcers and signs of acute pancreatitis. Prolonged severe hyperthyroidism is accompanied by the development of generalized fibrotic osteodystrophy, which is characterized by an increase in osteoclast activity and, as a result, the formation of fibrous degeneration and cystic bone restructuring of various localizations. The risk category for this pathology is patients with renal failure who are on prolonged dialysis, as well as patients with a secondary form of hyperparathyroidism. Laboratory confirmation of fibrotic osteodystrophy is a significant increase in serum levels of alkaline phosphatase.
Statistical data prove the possibility of a lethal outcome in hypercalcemia. Lethal outcome occurs with the development of shock and acute renal failure.
Hypercalcemia in children
Hypercalcemia refers to one of the forms of disturbed mineral metabolism and the incidence of this pathology is significantly lower in comparison with hypocalcemia, but despite this fact, this pathology in childhood always runs hard and needs immediate medical correction.
The appearance of certain clinical manifestations in hypercalcemia depends on the age of the patient and the degree of increase in the saturation of blood serum with calcium. Different age categories are characterized by the development of various forms of this pathology, which are fundamentally different in the nature of the occurrence of hypercalcemia and, accordingly, approaches to its treatment.
For example, the neonatal period is considered critical for the development of Williams syndrome, which in pediatrics is called "idiopathic hypercalcemia".The cause of this pathology is a congenital genetic mutation, and the main pathogenetic mechanism of hypercalcemia is the enhancement of calcium absorption in the small intestine.
Given the experience of long-term follow-up of patients suffering from idiopathic hypercalcemia, a classical triad of clinical signs was identified: a sharp lag in mental development, severe vascular anomalies and a change in the facial part of the skull with the formation of a phenotypic "elf face".Over time, children suffering from this form of hypercalcemia are more likely to develop cognitive and intellectual disorders.
Unfortunately, at present, it has not been possible to develop diagnostic methods for determining the signs of Williams syndrome in the prenatal period. The main therapeutic measures for this pathology is the restriction of daily calcium intake by the child, as well as the observance of specific dietary nutrition of the mother during lactation, control of the dosing of the vitamin D solution, and only the administration of glucocorticosteroid therapy( hydrocortisone in a daily dose of 10 mg per 1 kgWeight of the child).
The family heterozygous type also belongs to the congenital form of hypercalcemia, which is characterized by a benign course and the absence of specific clinical signs allowing early diagnosis of this pathological condition.
Family hypercalcemia is most often an accidental finding in a planned screening laboratory examination of a child and does not require the use of medication.
Hypocalcauroic hypercalcemia belongs to the category of urgent conditions requiring immediate medication, since this pathology is characterized by a rapidly progressive aggressive course. The manifestations of this form of hypercalcemia are observed immediately after the birth of the child, and consist in the development of gross congenital anomalies of the skeleton, a sharp delay in the physical and mental development of the newborn. In addition to the critically high level of calcium in the serum, the biochemical laboratory criteria of this pathology include an increase in the concentration of parathyroid hormone and a significant decrease in the level of calcium in the urine. In view of the fact that hypocalciuric hypercalcemia in most cases has an unfavorable outcome, children immediately after birth are recommended to perform removal of parathyroid glands with simultaneous autotransplantation of the parathyroid tissue site into the muscular forearm mass area. Long-term rehabilitation treatment consists in the use of calcium-containing drugs and a solution of vitamin D.
Nonspecific form of hypercalcemia, which is observed in both the adult category of patients and among children is immobilization. This pathology develops as a result of demineralization of bone tissue in areas that are long in immobilized position with severe polytrauma or burn injury. In this regard, the most effective way to prevent the development of signs of hypercalcemia in this group of patients is their activation in the early rehabilitation period. With the available signs of immobilization hypercalcemia, an adequate scheme of diuretic therapy( Furosemide at a calculated dose of 1 mg / 1 kg of the child's weight intravenously) has a good effect.
In case of non-compliance with the intake of synthetic preparations of vitamin D, which is used both as a preventive and therapeutic agent in the nursing period, conditions for the development of signs of hypercalcemia are created. In this situation, the initial measures are the immediate cessation of taking the drug containing vitamin D, as well as the correction of the child's eating behavior, meaning abstinence from eating foods that contain calcium.
Treatment of hypercalcemia
The volume of necessary medical measures directly depends on the degree of serum calcium concentration, as well as on the existing background disease, which became the primary cause of the development of hypercalcemia.
The diet for hypercalcemia belongs to the category of secondary conservative methods of treatment and in a serious situation it must necessarily be supplemented with drugs of the medicament series.
In case when the patient shows a sharp increase in the concentration of calcium in the blood serum, as well as in severe hypercalcaemia, it is necessary to urgently use medication correction methods.
When the patient does not show signs of impaired renal function, it is advisable to use intravenous infusion of sodium chloride, the action of which is aimed at stimulation of calciuria. Effective is an infusion, in which the volume of diuresis daily is at least three liters. After the introduction of 0.9% sodium chloride in a volume of two liters, it is necessary to stimulate diuresis using diuretic drugs( Furosemide 80 mg parenterally at a frequency of every 8 hours and a duration of at least 2 days).The obligatory component of the diuretic therapy scheme is the use of potassium chloride drugs, the action of which is aimed at preventing possible hypokalemia.
In a situation where a severe form of hypercalcemia is observed in patients on the background of existing renal failure, the maximum and fastest effect is the method of hemodialysis, implying the use of solutions containing calcium in minimal amounts. The drug of choice in this situation is a solution of potassium and sodium phosphate, which in the volume of one dose with an intravenous method of administration allows eliminating manifestations of hypercalcemia for two weeks. This technique should be used with caution, since it has a number of adverse reactions, among which the formation of calcifications in soft tissues, especially at injection sites, is most frequent.
Patients with hypercalcemia of paraneoplastic genesis are recommended to use Mithramycin in a daily dosage of 25 mg / kg of weight of the patient by intravenous route. But it should be taken into account that this drug belongs to the category of highly toxic pharmacological preparations, therefore it is necessary to dose the injected drug with particular care.
In the treatment of chronic form of hypercalcemia, salmon calcitonin should be preferred in a maximum daily dosage of 8 IU / 1 kg of the patient's weight subcutaneously or Prednisone in a daily dose of 60 mg orally. These drugs are used to stop severe paraneoplastic hypercalcemia, if the application of sodium chloride has not had a positive effect. Calcitonin analogue with greater efficacy in correcting hypercalcemia is Gallium Nitrate in a single dose of 200 mg, the duration of which in some cases exceeds 15 days. Due to the fact that this drug has a wide range of adverse reactions, including the development of signs of acute renal failure, its scope of application is sharply limited by a one-off procedure to relieve the acute phase of hypercalcemia.
As a drug for prolonged therapy of hypercalcemia, a solution of neutral phosphate should be used orally. The only contraindication for its use is a severe degree of renal failure.
In the case of hypercalcemia in the background of hyperparathyroidism, which has a progressive course, the use of surgical methods of treatment is indicated. The detection of localization of parathyroid tissue can be a certain complication, for which various radial imaging methods are used, however, the method of computed tomography has the highest reliability in this situation. The performed operation is considered successful if the serum calcium concentration is normalized within 24 hours.