After screening 180 admittents to the PICU at Cairo University’s Hospital from April 2021 to December 2021, 49 (27.2%) patients were found to satisfy the inclusion and exclusion criteria.The study was conducted on 44 patients only who agreed to participate voluntarily in the study. According to the Gomez classification, the 44 patients were assigned to two groups; group A (well-nourished; n = 22) and group B (malnourished; n = 22). Group B was furtherly classified into the three degrees of malnutrition (Table 1).

In the current study, group A had a mean age of 36 months, with 12 (54.5%) males and 10 (45.5%) females (range: 2–132 months). There were 15 (68.2%) females and 7 (31.8%) males in group B, with a mean age of 13 months (range: 2–132 months). Age and sex did not significantly differ between the two groups (p = 0.335 and 0.128, respectively).

According to the anthropometric evaluation of the enrolled patients, group A's mean weight was 18.8 kg (4–71), and group B's was 7 kg (1.9–54). The weight was significantly different between the two groups (p = 0.007). The weight percentile between the two groups varied significantly (p = 0.001) (Table 2). The average heights in groups A and B were 84 cm and 67 cm, respectively. Height did not significantly differ between the two groups (p = 0.204).

Neurological conditions like cerebral palsy and GBS were the most frequent reasons for admission (32.2%). ARDS (27.2%), cardiac conditions including CHD (18.2%), shock (9.1%), metabolic (6.95), postoperative (4.6%), and renal conditions such ARF (2.3%) were other reasons.

No significant differences (p > 0.05) were identified between the two groups for the basic investigations (complete blood count, blood chemistry, and arterial blood gases) and serum prealbumin, according to the findings of laboratory tests.

The PRISM score was computed using the clinical and laboratory data from the first day of hospitalization. For group A, the PRISM scores varied from 8 to 19, with a mean of 11; for group B, they ranged from 4 to 17, with a mean of 12. For the recorded PRISM score, there was no significant difference between the two groups (p > 0.05). The PRISM III score did, however, significantly positively correlate with the outcome being higher in non-survivors (p = 0.003) (Table 3).

Prealbumin failed to significantly (p > 0.05) correlate as a nutritional laboratory biomarker with any of the assessed anthropometric measurements, nutritional state, vital signs, routine laboratory tests, or PRISM score (Table 4).

The mean length of stay (LOS) in the PICU was 11.57 days for group A and 18.68 days for group B. LOS in group B increased significantly (p = 0.027) more than in group A (Table 2). Of the 44 patients included in this study, 18 (40.9%) required MV during their time in the PICU, while 26 (59%) did not. 13 (59%) of the cases in group B and five (22.7%) of the cases in group A required MV. The requirement for MV varied significantly (p = 0.004) across the two groups (Table 2). The relationship between the outcome (mortality) and nutritional status was statistically significant (p = 0.042).

Regarding the results of our study, Mann–Whitney tests showed that non-survivor’s weight and weight SD significantly decreased compared to survivors (U = -1.952, p = 0.041 and U = -2.135, p = 0.033, respectively). However, there were no appreciable distinctions between survivors and non-survivors regarding demographic traits, height measurements, or vital signs (p > 0.05). The serum prealbumin level of survivors and non-survivors did not differ significantly according to the Mann–Whitney test (U = -0.356, p = 0.722). However, research showed that non-survivors had a significantly higher PRISM score than survivors (U = -2.953, p = 0.003). Grade of malnutrition and mortality had statistically significant positive correlations (2 = 12.78, p = 0.005) (Table 3).

The receiver operating characteristic (ROC) curve of serum prealbumin was plotted to assess the diagnostic precision of serum prealbumin for malnutrition in CIP. The results indicated that serum prealbumin performed poorly as a screening test for malnutrition in CIP, with an AUC of 0.556 (95% CI:0.398 to 0.705), a sensitivity of 90.91% (95% CI:70.8–98.9%), and specificity of 31.82% (95% CI:13.9–54.9%) in separating malnourished from well-malnourished CIP (Fig. 1).

The Receiver operating characteristic (ROC) curve analysis of serum pre-albumin level as a diagnostic marker for malnutrition

Regarding the prediction accuracy of the serum prealbumin for the clinical outcome, the ROC curve showed that the serum prealbumin has a sensitivity of 91.67% and a specificity of 21.8% in discriminating survivors from non-survivors with a best cutoff-point of ≤ 758.37 U/ml. The area under the curve (AUC) was 0.535 (Fig. 2).

The Receiver operating characteristic (ROC) curve analysis of serum Pre-albumin level as a diagnostic marker for clinical outcome