Calcemia and Inflammatory Markers in Early-Onset Neonatal Infection

The correlation between serum calcium levels and prognosis in patients with severe acute osteomyelitis

Objective

To explore the relationship between serum calcium levels and the prognosis of severe acute osteomyelitis, and to assess the effectiveness of calcium levels in prognostic evaluation.

Methods

Relevant patient records of individuals diagnosed with severe acute osteomyelitis were obtained for this retrospective study from the Medical Information Mart for Intensive Care (MIMIC-IV). The study aimed to assess the impact of different indicators on prognosis by utilizing COX regression analysis. To enhance prognostic prediction for critically ill patients, a nomogram was developed. The discriminatory capacity of the nomogram was evaluated using the Area Under the Curve (AUC) of the Receiver Operating Characteristic (ROC) curve, in addition to the calibration curve.

Result

The study analyzed a total of 1,133 cases of severe acute osteomyelitis, divided into the survivor group (1,025 cases) and the non-survivor group (108 cases). Significant differences were observed between the two groups in terms of age, hypertension, sepsis, renal injury, and various laboratory indicators, including WBC, PLT, Ca2+, CRP, hemoglobin, albumin, and creatinine (P<0.05). However, no significant differences were found in race, gender, marital status, detection of wound microbiota, blood sugar, lactate, and ALP levels. A multivariate COX proportional hazards model was constructed using age, hypertension, sepsis, Ca2+, creatinine, albumin, and hemoglobin as variables. The results revealed that hypertension and sepsis had a significant impact on survival time (HR=0.514, 95% CI 0.339-0.779, P=0.002; HR=1.696, 95% CI 1.056-2.723, P=0.029). Age, hemoglobin, Ca2+, albumin, and creatinine also showed significant effects on survival time (P<0.05). However, no statistically significant impact on survival time was observed for the other variables (P>0.05). To predict the survival time, a nomogram was developed using the aforementioned indicators and achieved an AUC of 0.841. The accuracy of the nomogram was further confirmed by the ROC curve and calibration curve.

Conclusion

According to the findings, this study establishes that a reduction in serum calcium levels serves as a distinct and standalone predictor of mortality among individuals diagnosed with severe acute osteomyelitis during their stay in the Intensive Care Unit (ICU) within a span of two years.

Cerebral Hemodynamic and Metabolic Abnormalities in Neonatal Hypocalcemia: Findings from Advanced MRI

BACKGROUND AND PURPOSE

Neonatal hypocalcemia is the most common metabolic disorder, and whether asymptomatic disease should be treated with calcium supplements remains controversial. We aimed to quantify neonatal hypocalcemia's global CBF and cerebral metabolic rate of oxygen (CMRO2) using physiologic MR imaging and elucidate the pathophysiologic vulnerabilities of neonatal hypocalcemia.

MATERIALS AND METHODS

A total of 37 consecutive patients with neonatal hypocalcemia were enrolled. They were further divided into subgroups with and without structural MR imaging abnormalities, denoted as neonatal hypocalcemia-a (n = 24) and neonatal hypocalcemia-n (n = 13). Nineteen healthy neonates were enrolled as a control group. Brain physiologic parameters determined using phase-contrast MR imaging, T2-relaxation-under-spin-tagging MR imaging, and brain volume were compared between patients with neonatal hypocalcemia (their subgroups) and controls. Predictors for neonatal hypocalcemia-related brain injuries were identified using multivariate logistic regression analysis and expressed as ORs with 95% CIs.

RESULTS

Patients with neonatal hypocalcemia showed significantly lower CBF and CMRO2 compared with controls. Furthermore, the neonatal hypocalcemia-a subset (versus controls or neonatal hypocalcemia-n) had significantly lower CBF and CMRO2. There was no obvious difference in CBF and CMRO2 between the neonatal hypocalcemia-n subset and controls. CBF and CMRO2 were independently associated with neonatal hypocalcemia. The ORs were 0.80 (95% CI, 0.65-0.99) and 0.97 (95% CI, 0.89-1.05) for CBF and CMRO2, respectively.

CONCLUSIONS

Neonatal hypocalcemia with structural damage may exhibit lower hemodynamics and cerebral metabolism. CBF may be useful in assessing the need for calcium supplementation in asymptomatic neonatal hypocalcemia to prevent brain injury.

Serum Calcium Level Combined with Platelet Count May Be Useful Indicators for Assisted Diagnosis of Extremity Posttraumatic Osteomyelitis: A Comparative Analysis

Background

A previous study had reported that patients with osteomyelitis (OM) appeared to be more likely to develop hypocalcemia before and after surgery. Calcium sulfate (CS) is frequently used as a local antibiotic vehicle in the treatment of OM, which may also affect serum calcium level. However, whether changes of serum calcium level are caused by OM and/or local use of calcium sulfate remains unclear. Also, platelet (PLT) count plays a crucial predictive role in periprosthetic joint infections (PJIs), but its role in assisted diagnosis of OM is largely unknown. The purpose of this study was to determine whether serum calcium level and PLT count may be helpful in assisted diagnosis of PTOM.

Methods

Between January 2013 and December 2018, we analyzed 468 consecutive patients (392 males and 76 females), including 170 patients with posttraumatic OM (PTOM), 130 patients with aseptic bone nonunion (ABN), and 168 patients recovered from fractures with requirement of implant removal set as controls. Preoperative serological levels of calcium, phosphorus, and PLT were detected, and comparisons were conducted among the above three groups. Additionally, correlations and receiver operating characteristic (ROC) curves were displayed to test whether calcium level and PLT can differentiate patients with ABN and PTOM.

Results

Outcomes showed that the incidences of asymptomatic hypocalcemia (PTOM vs. ABN vs. controls = 22.94% vs. 6.92% vs. 8.82%, χ² = 21.098, P < 0.001) and thrombocytosis (PTOM vs. ABN vs. controls = 35.3% vs. 13.84% vs. 12.35%, χ² = 28.512, P < 0.001) were highest in PTOM patients. Besides, the mean serological levels of phosphorus in PTOM and ABN patients were significantly higher than those in the controls (P = 0.007). The Area Under the Curve (AUC) of the ROC curve outcomes revealed that, with the combination of serum calcium level with PLT count, the predictive role was acceptable (AUC 0.730, P < 0.001, 95% CI 0.681-0.780). Also, serological levels of calcium of 2.225 mmol/L and PLT count of 246.5 × 10⁹/L were identified as the optimal cut-off values to distinguish patients with and without PTOM. However, age- and gender-related differences in serum calcium levels (age, P = 0.056; gender, P = 0.978) and PLT count (age, P = 0.363; gender, P = 0.799) were not found to be statistically significant in any groups. In addition, no significant correlations were identified between serum calcium level and PLT count (R = 0.010, P = 0.839).

Conclusions

Asymptomatic hypocalcemia and thrombocytosis appeared to be more frequent in this cohort with PTOM. Serological levels of calcium and PLT count may be useful biomarkers in screening patients suspected of PTOM.

Prognostic Value of Ionized Calcium Levels in Neonatal Sepsis

BACKGROUND

Despite recent advances in the treatment of neonatal infection, mortality rates and comorbidities associated with neonatal sepsis remain high. Hypocalcemia has been reported in critically ill patients, especially in as-sociation with sepsis. However, the importance of hypo-calcemia in neonatal sepsis has not been explored in detail.

OBJECTIVES

The purpose of this study was to evaluate the prognostic value of hypocalcemia in neonatal sepsis patients and to identify the risk factors associated with sepsis-related mortality.

METHODS

This retrospective study examined perinatal data from patients in a level IV neonatal in-tensive care unit between January 2010 and June 2016. Univariate analysis was performed to understand the differences in clinical and laboratory characteristics between patients with and without neonatal sepsis. Neonates with sepsis were further stratified as having ionized hypocalcemia (if serum ionized calcium [iCa] <1.0 mmol/L) or not. Uni- and multivariate logistic regression analyses were utilized to evaluate the predictive potential of iCa for identifying sepsis-related mortality.

RESULTS

A total of 472 neonates were enrolled in this study, including 169 neonates diagnosed with culture-proven sepsis and 303 neonates without infection (control group). The comparison of neonates with and without sepsis highlighted significant differences in levels of iCa (0.97 ± 0.26 vs. 1.12 ± 0.25 mmol/L), magnesium (0.75 ± 0.22 vs. 0.89 ± 0.12 mmol/L), and phosphate (2.26 ± 1.08 vs. 1.65 ± 0.85 mmol/L; all p < 0.001). When neonates with sepsis were stratified into 2 subgroups based on serum iCa, neonates with hypocalcemia showed higher rates of organ dysfunction than those with normal iCa, as well as higher rates of cardiovascular system dysfunction (37.35 vs. 17.44%), renal dysfunction (34.94 vs. 30.95%), disseminated intravascular coagulation (26.51 vs. 11.63%), and seizure (16.04 vs. 5.8%; all p < 0.05). Among all neonates who had sepsis, the mortality rate was 13.61%, and this rate was higher among neonates with hypocalcemia than among those with normal iCa (20.48 vs. 6.98%, p < 0.05). Uni- and multivariate analyses showed that acidosis, hypoalbuminemia, hypocalcemia, and hyperphosphatemia were independent prognostic markers of sepsis-related mortality. In receiver-operating characteristic curve analysis, the areas under the curve were 0.70 (95% CI 0.624-0.768; p = 0.0004), 0.74 (95% CI 0.671-0.808; p < 0.0001), 0.73 (95% CI 0.653-0.792; p = 0.0002), and 0.67 (95% CI 0.59-0.737; p = 0.0154) for serum albumin, iCa, phosphate, and acidosis, respectively. Based on these findings, we developed a nomogram to predict sepsis-related mortality.

CONCLUSIONS

Hypocalcemia is common in neonates with sepsis and is significantly associated with organ dysfunction and sepsis-related mortality.