Hyperparathyroidism in pregnancy

Introduction

Introduction to pregnancy with hyperparathyroidism Hyperparathyroidism (HPT) is referred to as hyperparathyroidism, which is rare in patients with pregnancy. Primary hyperparathyroidism is caused by the synthesis and secretion of parathyroid hormone (PTH) caused by the lesions of the parathyroid gland itself (tumor or hyperplasia, of which about 85% of the tumors), through the action on bone and kidney. Lead to hypercalcemia and hypophosphatemia, secondary hyperparathyroidism is caused by hypercalcemia caused by various causes of parathyroid glands, hypertrophy, excessive secretion of PTH, common in the kidney Insufficient function, osteomalacia. A small number of patients with long-term stimulation of the gland, part of the hyperplastic tissue into adenoma, autonomously secreted too much PTH, known as three-fold hyperparathyroidism. basic knowledge The proportion of illness: 0.001% Susceptible population: pregnant women Mode of infection: non-infectious Complications: Kidney stones, pyelonephritis, pancreatitis, peptic ulcer, hypertension

Cause

Pregnancy with hyperparathyroidism

(1) Causes of the disease

80% of hyperparathyroidism is caused by parathyroid adenoma, a small number is due to glandular hyperplasia, the latter accounts for about 15%, and some are ectopic parathyroid glands, parathyroid adenoma (Montoro, 2000), due to thyroid Parathyroid adenoma, glandular hyperplasia, leading to excessive secretion of parathyroid hormone and a series of disorders of calcium and phosphorus metabolism, the true cause of hyperparathyroidism is not clear, some cases have a genetic predisposition.

(two) pathogenesis

Hyperparathyroidism, increased secretion of parathyroid hormone (PTH), PTH is a single-chain polypeptide containing 115 amino acids, PTH and vitamin D regulate calcium and phosphorus metabolism, and parathyroid hormone promotes kidney formation. Vitamin D metabolites, the role of parathyroid hormones mobilize calcium and phosphate in the bone into the blood, accelerate bone absorption, increase renal tubular reabsorption of calcium; increase intestinal absorption of calcium, reduce renal tubular to phosphoric acid The absorption of salt, after the release of parathyroid hormone from the gland, causes calcium to enter the extracellular fluid within a few minutes. When the parathyroid function is hyperthyroidism, the secretion of parathyroid hormone increases for a long time, which will inhibit the function of osteoblasts and promote Osteolysis, neonatal morbidity and mortality after pregnancy with hyperparathyroidism increased, 80% of abortion, stillbirth or neonatal hand and foot stagnation, combined with this disease due to elevated blood calcium, calcium actively through the placenta, A large amount of calcium is transferred to the fetus, and the fetal blood calcium concentration is increased. By regulating the PTH secreted by the parathyroid glands, the secretion of active vitamin D3 is also reduced, and the amount of mobilized bone calcium is reduced, and the newborn is born. Suddenly separated from the high calcium environment, the neonatal blood calcium suddenly drops from a high level, stimulating the secretion of parathyroid hormone in the neonatal parathyroid gland, which takes a certain time, so the newborn can have hand and foot due to hypocalcemia in the short term after birth. Hysteria, neonatal convulsions, severe cases can cause permanent hypoparathyroidism, increase neonatal prevalence and mortality.

Prevention

Pregnancy with hyperparathyroidism prevention

The following conditions in PHPT are critical signs, should promptly correct high blood calcium, and strive for early surgery 1 long-term hypercalcemia lesions, such as kidney stones, kidney failure, fibrous cystic osteitis hunchback, height shortened pseudo-like Refers to (suggestion of severe osteitis at the end of the phalanx), severe myopathy, metastatic calcification (including calcification of the pulmonary and renal vascular joints and "red eyes" caused by deposition of calcium phosphate in the conjunctival keratoconus), anemia (due to excessive PTH can induce bone marrow fibrosis and decreased hematopoietic function). 2 There are signs of severe hypercalcemia, such as blood calcium >3.5mmol / L (14mg / dl), as well as neuropsychiatric symptoms.

Complication

Pregnancy complicated with hyperparathyroidism Complications Kidney stones, pyelonephritis, pancreatitis, peptic ulcer hypertension

Maternal complications include spit, kidney stones and pyelonephritis, pancreatitis, peptic ulcer, hypertension and bone disease.

Symptom

Pregnancy with hyperparathyroidism Symptoms Common symptoms Polyuria, sleepiness, kidney stones, hallucinations, loss of appetite, coma, bone pain, constipation, bone cyst, bloating

The disease is more common in 20 to 50 years old, more women than men, generally slow onset, various clinical manifestations, some with repeated kidney stones as the main performance; some with bone disease as the main performance; some due to blood Calcium is too high and is a symptom of neurosis, and some are found because of multiple endocrine neoplasia; some are always asymptomatic and can be summarized as follows.

Hypercalcemia

Hypophosphatemic syndrome due to the massive secretion of PTH, increased renal tubular reabsorption of calcium, and promoted the release of phosphorus, increased urinary phosphorus, thus the formation of hypercalcemia and hypophosphatemia, PTH can also promote in the kidney 25 ( OH)D3 is converted to the more active 1,25(OH)2D3, which promotes the absorption of intestinal calcium and further aggravates hypercalcemia, which can cause the following systemic changes:

(1) Central nervous system: memory loss, emotional instability, personality changes, depression, lethargy, patients can be mistaken for neurosis, when serum calcium exceeds 3mmol / L, there may be hallucinations, arrogance, coma.

(2) Muscle system: burnout, weakness of limbs, proximal muscles, muscle atrophy, often accompanied by abnormal EMG, can be misdiagnosed as primary neuromuscular disease, calcium can be deposited in soft tissue, tendon and cartilage , causing non-specific joint pain.

(3) Digestive system: loss of appetite, bloating, indigestion, nausea, vomiting, constipation, can also cause acute pancreatitis, due to the role of high blood calcium or accompanied by islet gastrinoma, can cause pepsin increase Increased gastric acid secretion, some patients with duodenal ulcer and multiple refractory gastrointestinal ulcers.

Patients with hyperparathyroidism may have a hypercalcemia crisis, which means that the blood calcium is higher than 3.75 mmol/L. All the above systems may have obvious symptoms, and may even have renal insufficiency, uremia symptoms, arrhythmia, and coma.

2. Urinary system

Long-term hypercalcemia can affect the conserving function of renal tubules, such as polyuria, nocturia, thirst, etc. When serum calcium is further increased, urinary calcium can be increased in a large amount, and urinary phosphorus excretion is also increased, which can cause multiple kidney stones and Renal calcareous deposits, recurrent renal colic and hematuria can occur, affecting renal function, PTH also affects renal tubular reabsorption of bicarbonate, making urine alkaline, further promoting the formation of kidney stones, urinary tract stones can induce urinary tract Infection and urinary tract obstruction cause chronic pyelonephritis, further affecting renal function.

3. Skeletal system

Early bone pain can be located in the back, spine, hip, thoracic ribs or limbs, local tenderness, late manifestation of fibrocystic osteitis, skeletal deformities and pathological fractures, short stature, lower limbs can not support weight, Difficulties in walking, some patients may have bone cysts, manifested as local bone bulge.

4. Other

Patients with hyperparathyroidism may have a family history, often as part of a multiple endocrine neoplasia, either in combination with pituitary tumors and insulinomas, or with pheochromocytoma and medullary thyroid carcinoma, sometimes with a family history Hyperparathyroidism may not be associated with other endocrine gland diseases, often caused by parathyroid hyperplasia.

Examine

Pregnancy with hyperparathyroidism

The serum total calcium is higher than that of normal pregnant women. The serum calcium concentration in normal pregnancy should not be higher than 2.5mmol/L. If it is higher than this value, it is suspected to be hyperparathyroidism. The average calcium in patients with hyperparathyroidism is 2.6~2.7mmol. Above /L, early blood calcium instability, should be repeated multiple times, while blood PTH increased, urinary calcium increased, serum phosphorus decreased significantly, serum alkaline phosphatase increased.

1. X-ray findings X-ray film has subperiosteal cortical absorption, cyst-like changes, multiple fractures and deformities, especially the subperiosteal cortex absorption of the medial bone, which is one of the characteristics of parathyroidism.

2. Ultrasound examination can be found in parathyroid adenomas.

Diagnosis

Diagnosis and differentiation of pregnancy complicated with hyperparathyroidism

The diagnosis depends on laboratory examination, elevated total calcium, elevated free calcium, decreased blood phosphorus, and significantly increased PTH, but mild blood calcium can be normal high value, thyroid B ultrasound is helpful for diagnosis.

First of all, it must be differentiated from other diseases that cause hypercalcemia, such as multiple myeloma, sarcoidosis, excessive vitamin D, long-term use of thiazide diuretics and other hypercalcemia, cortisol inhibition test, prednisone Song 30mg per day, for 10 days, the above disease can be inhibited by blood calcium, while the blood calcium of parathyroidism is not inhibited, but also need to distinguish secondary hyperparathyroidism, the patient's blood PTH increased, but serum calcium Often reduced, high blood phosphorus, mostly caused by chronic renal insufficiency.

Was this article helpful?

The material in this site is intended to be of general informational use and is not intended to constitute medical advice, probable diagnosis, or recommended treatments.