Hypocalcemia in the newborn

A case-controlled investigation of risk factors associated with molar incisor hypomineralization (MIH) in 8-12 year-old children living in Chandigarh, India

PURPOSE

Despite mounting evidence in favour of various perinatal risk factors for occurrence of MIH, verification of these remains doubtful because of lack of documented proof. The present study was aimed at examining the putative risk factors for MIH based on hospital-maintained records assessment.

METHODS

A total of 3176, 8-12 year-old children were screened for MIH using EAPD criteria (2003). Of these, risk factor analysis was carried out for 104 MIH affected and 211 non-MIH affected children with complete peri-natal medical records maintained up to 3 year post-birth. Chi-square test was used for risk factor comparison, while significance was assessed using logistic regression.

RESULTS

Prevalence of MIH in study population was 11.72% (372/3176). Various pre-natal, natal and post-natal risk factors including intra-uterine growth retardation (6.7 vs. 1.4%); maternal anaemia (10.6 vs. 3.8%) and neonatal jaundice (29.8 vs. 14.2%) were significantly higher in the MIH group. Furthermore, pre-term birth (OR 3.01), low birth weight (OR 2.37), more than three pyrogenic episodes (OR 7.61) and consumption of Amoxicillin Clavulanate (OR 3.01) were significantly associated with higher risk of developing MIH.

CONCLUSIONS

Pre and post-natal risk factors showed a moderate to high association for occurrence of MIH although social and nutritional factors had a lesser association.

The many etiologies of neonatal hypocalcemic seizures

Seizures during the neonatal period have a broad differential diagnosis. Unlike in developing countries where hypovitaminosis D and hypocalcemia constitutes a major cause of infantile seizures, the number of neonatal seizures attributed to hypocalcemia in developed countries has decreased dramatically due to the improvement of infant formulas and vitamin D supplementation. In these countries, most infants that present with hypocalcemic seizures have underlying endocrinological etiologies rather than dietary insufficiencies. Here, we describe 3 cases of neonatal seizures due to hypocalcemia. Although the symptoms and calcium concentrations at presentation were similar in all 3 cases, the course of the disease and the final diagnosis for each were distinct. The cases are presented along with a brief review of the pathophysiology, differential diagnosis, and treatment of neonatal hypocalcemia.

Molar-incisor-hypomineralisation (MIH). A retrospective clinical study in Greek children. II. Possible medical aetiological factors

AIM

This was to examine the potential medical aetiological factors involved in the development of MIH.

METHODS

During the years 2003--2005, all MIH cases diagnosed according to set criteria were selected from the new patients clinic of a Community Dental Centre for Children (Athens). The age, gender and teeth involved were recorded. A control group of socio-demographically matched controls was also identified. The potential aetiological factors were retrieved through personal interview with the parents and from each child and mother's medical book. Only verified aetiological factors were recorded. Evaluation of the correlation of affected teeth and the timing of the insult was performed in a separate group of 225 affected children aged 8-12 with their entire 12 'index' teeth erupted.

RESULTS

From the 3,518, 5.5 to 12 years old children examined, 360 (10.2%) had MIH. Aetiology of MIH: 44 children (12.2%), presented without any relevant medical history, the remaining 316 (87.8%) recorded various medical problems associated with MIH, compared with 18.9% for controls. Perinatal (163, 33.6%) and postnatal (162, 33.9%) problems were the most frequently found and prenatal the least (33, 8.6%). For 42 children (11.7%) problems occurred in more than one chronological period, mainly during both the perinatal and postnatal period (11.1%). The most common prenatal problem was repeated episodes of high fever (12/33), in the perinatal period birth by Caesarean section (92/163) and other birth complications (34/163). Various respiratory conditions (88/162), repeated episodes of high fever (31/162) and neonatal illness (28/162) were the commonly reported problems in the postnatal period. Many MIH cases presented with more than one medical problem during the peri-and postnatal period.

STATISTICAL ANALYSIS

Children with MIH recorded 68.9% more frequent medical problems than controls (p<0.0001). A positive correlation (p<0.001) between the total number and type of affected teeth with the timing of the insult was observed in the 225 MIH children with all their 'index' teeth erupted.

CONCLUSION

Children with MIH present with more medical problems than controls during their prenatal, perinatal and postnatal period. The majority of these illnesses may produce hypocalcaemia, hypoxia and pyrexia to the child or the mother. The number of affected teeth was associated with the timing of the possible insult; children with prenatal, perinatal and postnatal problems present more affected teeth in increasing order.

Neonate capillary blood gas reference values

OBJECTIVES

Because biological data are instrument-dependent and because technology has evolved over the last two decades, the published capillary blood reference values for blood gases, lactate, ionized calcium (iCa) and glucose may not reflect the present day situation. Hence, we report such values for healthy term neonates at 48 +/- 12 h of life.

DESIGN AND METHODS

The Institution Ethics Review Board for Research on Human Subjects has accepted the protocol. Extra blood sample was obtained at the time heel-pricks were performed in the frame of the Quebec genetic screening program. One hundred twenty-six term neonates (39.6 +/- 1.2 weeks of gestation) were included in the study. pH, pO2, pCO2, lactate, ionized calcium and glucose were simultaneously measured with selective electrodes on the ABL 735 blood gas analyzer (Radiometer).

RESULTS

All variables exhibited a Gaussian distribution. Since there was no gender effect, all data were pooled.

Assessment and management of patients with abnormal calcium

Calcium is essential for homeostasis, and normocalcemia should be maintained strictly during the perioperative period. The biochemistry of calcium equilibrium results from the calcium-sensing receptors on the parathyroid glands, which detect changes in calcium concentrations and initiate the proper response. Asymptomatic hypercalcemia is a common metabolic derangement that is often discovered on routine serum screening. The most common etiologies are primary hyperparathyroidism and cancer. Increasingly, parathyroidectomy is the preferred therapy for primary hyperparathyroidism. Severe hypercalcemia ("hypercalcemic crisis") should be managed aggressively with a combination of intravenous fluids, steroids, bisphosphonates, and calcitonin. Some of these patients may require an urgent parathyroidectomy for calcium control. Hypocalcemia needs to be verified, as many cases of hypocalcemia are the artifact of hypoalbuminemia. Severe hypocalcemia occurs after subtotal or total parathyroidectomy with auto transplantation as well as after massive resuscitation or blood transfusion. Strategies aimed at correcting calcium concentrations depend on the severity of symptomatology. If symptoms are mild, oral calcium supplementation can be given; otherwise, intravenous calcium should be administered.