[Katacalcin levels in healthy children and children with spasmophilia]

The calcitonin (CT) gene encodes at least 3 peptides: CT, the 21-aminoacid carboxyl-terminal flanking peptide (katalcin or PDN-21) and CT-gene related peptide. Normal thyroid C-cells as well as malignant ones co-secrete CT and PDN-21 in response to hypercalcemia, so assay of PDN-21 may be an usefull method to assess C-cells secretion. Because of our knowledge no data are available on PDN-21 values in children, we measured this peptide in healthy children and in spasmophilia (Sp), a disease that has been related to CT deficiency. We studied 16 healthy children (9 males, 7 females; aging from 3.0 to 11.6 years) and in 21 patients with diagnosed Sp (8 males, 13 females, aging from 4.6 to 13.0 years). PDN-21 were assayed in whole serum by RIA using synthetic human PDN-21 for standards, 125I-PDN-21 for tracer and specific antiserum. CT was measured the serum of the same subjects by RIA using an ultrasensitive methods. In healthy children PDN-21 serum values were 12.3 +/- 2.0 pg/ml and no significant differences were found between males and females. Children with Sp showed slow higher PDN-21 concentrations (14.0 +/- 1.4 pg/ml) than normals, but the difference was not statistically significant. Also CT values were not significantly different between normal children (21.4 +/- 3.7 pg/ml) and patients with spasmophilia (22.5 +/- 1.8 pg/ml). A high significant positive relation was found between katalcacin and CT levels in normals as well as in spasmophilics. The physiological effects of PDN-21 are actually unknown.(ABSTRACT TRUNCATED AT 250 WORDS)

[The mechanism of postoperative tetany in Graves' disease]

The levels of serum calcium (Ca), inorganic phosphate (P) and mid-molecular parathyroid hormone (PTH) were measured in 37 patients with Graves' disease (12 in hyperthyroid state, 25 in euthyroid state followed by subtotal thyroidectomy), 6 with papillary carcinoma of the thyroid, 8 with benign nodular goiter and 19 healthy control subjects in order to investigate the change in these levels before and after thyroidectomy. The levels of serum Ca and P of the hyperthyroid patients with Graves' disease were 9.73 +/- 0.30 mg/dl and 4.47 +/- 0.44 mg/dl, respectively, which were significantly higher than those of healthy control subjects. No significant difference in the levels of serum PTH was observed between hyperthyroid patients with Graves' disease and healthy control subjects. The levels of serum Ca, P and PTH of euthyroid patients with Graves' disease were not significantly different from those of healthy control subjects. In the patients with Graves' disease who had undergone subtotal thyroidectomy followed by postoperative tetany, serum Ca and serum PTH decreased significantly from 9.39 +/- 0.45 mg/dl to 7.90 +/- 0.33 mg/dl and from 406.6 +/- 164.4 pg/ml to 229.9 +/- 136.0 pg/ml, respectively, after surgery, but there was no change in serum P. In the patients without postoperative tetany, serum Ca and serum P decreased significantly after surgery from 9.65 +/- 0.36 mg/dl to 9.15 +/- 0.33 mg/dl and from 4.03 +/- 0.46 mg/dl to 3.47 +/- 0.54 mg/dl, respectively, without any change in the levels of serum PTH. In the patients with papillary carcinoma or benign nodular goiter without postoperative tetany, the levels of serum Ca, P and PTH did not change after surgery. In the patients with papillary carcinoma followed by postoperative tetany, serum Ca decreased significantly after surgery with concomitant decrease of serum PTH. It was concluded that excessive thyroid hormones influenced Ca metabolism, and the transient tetany following subtotal thyroidectomy for Graves' disease seemed to be due to both the absorption of Ca by hungry bone and parathyroid hypofunction.

[Tetany secondary to hypokalemia]

The authors describe a case of tetany not related to the common causes of this clinical symptom, such as hypocalcemia, hypomagnesemia, and alkalosis. Severe hypokalemia secondary to the use of diuretics was detected; its correction reverted the symptoms.

Computerized electroencephalographic mapping in hypomagnesian spasmophilic syndromes

Out of 397 patients presenting hypomagnesaemia there were selected for this study only 107 cases with neurotic and neuromuscular clinical picture (sometimes with short and simple loss of consciousness) without any sign of organic cerebral lesion. The dosing of the seric and erythrocytic magnesium was performed by means of a colorimetric method of Mann and Yoe, modified by the authors. In all the cases, the EEG and EMG changes were studied by simultaneous recording of the EEG and EMG before, during and after hyperpnoea. In these 107 selected cases (divided into three groups: children, adolescents and adults) the computerized electroencephalographic maps (CEM) were carried out by an original method, transcribing the primary data of Hjorth's NSD parameters (Amplitudes and Frequencies) into a Romanian M-118 microcomputer, by a technique with analog-digital conversion. The CEM (in white-black and in colour cartography) were performed for various epochs, including the sequential ones (second by second, all along the EEG discharges during and after hyperpnoea). By these methods, we analyzed the dynamic fluctuation and temporo-spatial cortical distribution of the sinusoidal slow waves generated by the reticulate neuronal hypersynchrony. The CEM showed some differences in the three groups of hypomagnesemic syndromes selected.

[Chronic normocalcemic constitutional tetany: clinic and etiopathogenic aspects. Description of a case]

Tetany is a state of hyperexcitability of the central and peripheral nervous system due to abnormal concentrations of serum electrolytes. However tetanic individuals without any detectable abnormalities, are also encountered. This last condition has been named "chronic normocalcemic tetany or spasmophilia". The case here reported, allows the authors to review the literature concerning normocalcemic tetany and let them focus on two similar and sometimes overlapping entities, spasmophilia and hyperventilation syndrome, both common causes of recurrent, atypical symptoms and tetany.

Electrical activity induced by ischemia in the skeletal muscle of patients with spasmophilia

The incidence of spontaneous electrical activity during ischemia was studied in normal and spasmophilic subjects with a Bronk electrode inserted in the first dorsal interosseous muscle. Subjects were of both sexes, aged 16 to 65 years. The diagnosis of spasmophilia was established electromyographically by a variant of the Alajouanine test. Ischemia induced in many cases an electrical activity consisting of discharge potentials that have the amplitude, duration and morphology of motor unit potentials. The number of discharging motor units varied, sometimes leading to an electrical Trousseau associated to a carpal spasm. The discharge of individual motor units was irregular and practically uninfluenced by passive manipulations on the muscle or voluntary contraction. The activity started usually 30 sec to 1 min after the onset of ischemia, reached a maximal intensity (as to the number of motor units and frequency of discharge) in about 1 min and declined gradually in the following minutes. This activity was encountered in 55.06% of 770 cases of spasmophilia and only in 11.66% of 283 normal subjects, with a tendency to more intense discharge in spasmophilia. Its incidence in the spasmophilic group was closely related to the intensity of spontaneous repetitive discharges appearing electromyographically after the activation test, reaching 78.63% in most severe cases. The behaviour was interpreted as indicating a higher susceptibility in spasmophilia of axons to depolarization induced by hypoxia. This higher susceptibility appears as an important component of the excitability alterations leading to the complex neuromuscular disorders occurring in spasmophilia.

[A case of spasmophilic syndrome]

The case is described of a 43 year old woman with spasmophilic syndrome. For 12 years she had suffered from fainting fits, marked morning asthenia, anxiety, depression, widespread arthromyalgia, blood pressure fluctuations, precordial pains, paresthesia and painful nocturnal cramp. This clinical picture appeared in a subject with a double left kidney and stones in the supernumerary ureter, enlargement of the pancreatic head and tail revealed by a CAT scan and an earlier cholecystectomy. Given the multiplicity of symptoms diagnosis was necessarily by a process of elimination. The data providing grounds for optimism were a positive Chvostek's sign, stable calcium phosphorus profiles, a reduction in ionised calcium and favourable eletromyographic readings.

Pathophysiology of pH and Ca2+ in bloodstream and brain

The highlights of the literature and our work on tetany and hyperventilation are reviewed. Our studies concern the following: (1) the changes of [Ca2+] in circulating plasma caused by respiratory and "metabolic" acidosis and alkalosis; (2) critical plasma [Ca2+] levels associated with signs of tetany and neuromuscular blockade; (3) changes in cerebral [Ca2+]o caused by hypo- and hyper-calcaemia, and the changes in cerebral [Ca2+]o and pHo caused by acute systemic acidosis and alkalosis; and (4) effects of changing [Ca2+]o and pHo levels on synaptic transmission in hippocampal formation. Our main conclusions are (1) changes of plasma [Ca2+] caused by "metabolic" pH changes are greater than those associated with varying CO2 concentration; (2) acute systemic [Ca2+] changes are associated with small cerebral [Ca2+]o changes; (3) the decreases in systemic and cerebral [Ca2+]o caused by hyperventilation are too small to account for the signs and symptoms of hypocapnic tetany; (4) moderate decrease of [Ca2+]o depresses and its increase enhances synaptic transmission in hippocampal formation; and (5) H+ ions in extracellular fluid have a weak depressant effect on neuronal excitability. CO2 is a strong depressant, which is only partly explained by the acidity of its solution. CO2 concentration is a significant factor in controlling cerebral function.

Calcium deficiency and supraorbital headache: a clinical study of adult subjects

The present study was aimed at investigating the relationship between "chronic constitutional tetany" (spasmophilia) and headache. Several adult patients presenting with neuromuscular hyperexcitability, anxiety, dysautonomia, and oculofrontal headache were subjected to a series of ion and hormone blood tests, and the results were compared with those in control subjects. Calcium and parathyroid hormone levels were significantly decreased, and phosphorus and beta-endorphin-like immunoreactivity were significantly increased. A subgroup of the patients had all four abnormalities. In most cases the family history was positive for headache. Sleep disturbances and personal histories of periodic syndrome in infancy were recorded. It is concluded that a correlation may exist between the symptoms assessed and an impairment of some ion and hormone levels. There are several traits in common with "common migraine", and our patients may form a subgroup of that group. A possible linkage between headache/tetany and the periodic and hyperventilation syndromes is discussed. The increased beta-endorphin-like immunoreactivity is putatively a reactive phenomenon.

Increased calcium tolerance in patients with tetania latenta

We studied the calcium tolerance on 59 subjects with tetania latenta. The calcium tolerance was tested by induced hypercalcemia (Klotz's test). In 12 cases the dynamic changes of serum magnesium were also investigated during the same test. Eight cases exhibited a normal tolerance and 51 exhibit an abnormal response, calcemia remaining at a high value after 4 hours of the test. The magnesium values remained low when finishing the test (p less than 0.001). It was concluded that 86 per cent of the subjects having tetania latenta and exhibiting an increase of calcium tolerance had a possible calcitonin deficiency. The significance of the magnesium decrease remains unclear. These phenomena have not been observed in Graves' disease and in the Turner's syndrome.

Magnesium concentrations in the ventricular and lumbar cerebrospinal fluid of hypomagnesaemic cows

Samples of ventricular and lumbar cerebrospinal fluid (CSF) were taken at intervals from six lactating dairy cows, made hypomagnesaemic by feeding a magnesium-deficient diet. Initially the ventricular CSF had a higher magnesium concentration than lumbar CSF but as the cows became hypomagnesaemic the magnesium concentration in ventricular CSF decreased more rapidly than that in lumbar CSF. Tetany occurred when the concentration of magnesium in ventricular CSF fell below about 0.5 mmol litre-1. Intravenous infusion of magnesium into two hypomagnesaemic cows increased the concentration of magnesium in ventricular CSF before there was any change in the lumbar CSF. Newly formed CSF from the ventricles appeared to be more sensitive to changes in the concentration of magnesium in plasma than lumbar CSF which equilibrates with the diffusible magnesium of the central nervous system.

Changes in blood composition of pregnant cows during the onset of hypomagnesaemia

Magnesium, calcium, phosphate, total protein and free fatty acid concentrations, and a lipase activity using p-nitrophenylpalmitate NP-C16) as a substrate, were determined in the serum of 15 pregnant Aberdeen Angus cows grazing a Phalaris tuberosa pasture with a tendency to induce tetany. A gradual decrease in magnesium concentrations, but no definite change in the other parameters, was observed when the results were plotted directly against the time of the experiment. When the results were plotted as a function of the stage of pregnancy or lactation of the animals, magnesium concentrations showed a more steady decrease which was associated with increases in calcium concentrations and, at the lowest magnesium concentrations, with increases in phosphate concentrations. Total proteins and free fatty acids remained fairly constant and the highest lipase activity was associated with parturition. The lowest magnesium concentrations in serum did not correspond with high levels of either lipase or free fatty acids. The hypomagnesaemia observed in this experiment was attributed to the high potassium:calcium and magnesium ratio in the pasture and to the physiological condition (pregnant and lactating) of the animals. None of the parameters evaluated in this paper would be more sensitive than serum magnesium levels for the early detection of the conditions that predispose grazing cattle to grass tetany.

[Current status of normocalcemic tetany]

The author describes the actual state of research of normocalcemic tetany. Since 1959 the infusion test with ethylene diamine tetraacetic acid (EDTA) has won a central position. The EDTA test gives the possibility to classify tetanic symptoms into the circle either of hypocalcaemic or normocalcaemic syndrome. In the latter case the functional disturbance is to be treated in a form of combined therapy by tranquilizers and psychosomatic measures.

Life span and tissue distribution of 111indium-labeled blood platelets in hypomagnesemic lambs

Circulating platelets may be activated by exposed triple-helical collagen in atherosclerotic lesions in Mg-deficient ruminants. Autologous platelets, labeled in vitro with 111In and determined to be active, were injected into 5 hypomagnesemic and 3 control lambs fed semipurified diets with 100 or 2,000 mg of Mg/kg of feed for 3 months. During the first 68 hours, 111In concentrations were 11 times higher in packed cells than in plasma. Packed-cell 111In increased 60% during the first 2 hours, probably due to initial tissue sequestration and later release of labeled platelets. Thereafter, platelet half-life span averaged 60 and 63 hours for hypomagnesemic and control lambs. After 68 hours, lambs were injected with native vascular collagen fibrils at 500 micrograms/kg of body weight to initiate reversible platelet aggregation. Within 1 minute, 83% of packed-cell 111In disappeared from circulation. Thirty minutes later, the lambs were euthanatized and necropsied and in the lungs, liver, and spleen, 111In averaged 24%, 19%, and 9%, respectively, of 111In injected 68 hours earlier. Organ deposits were not affected by Mg intake, but 111In in the lungs was somewhat lower in 2 lambs injected with inactivated collagen. Pathologic changes induced by reversible platelet aggregation were compatible with right ventricular failure complicated by pulmonary edema, similar to changes in hypomagnesemic lambs that died spontaneously. Platelets in blood exposed to vascular lesions in hypomagnesemic ruminants could be a major mortality risk factor in grass tetany disease.