Association of Placental Pathologic Findings with the Severity of Necrotizing Enterocolitis in Preterm infants - A Matched Case-Control Study.

OBJECTIVE: To determine the association of placental pathology with the severity of necrotizing enterocolitis (NEC) in preterm infants. METHODS: This single-center matched case-control study included infants with NEC (n = 107) and gestational age and birth weight-matched controls (n = 130), born between 2013 and 2020. Placentas were evaluated according to the Amsterdam Placental Workshop Group Consensus Statement. RESULTS: Acute histologic chorioamnionitis with the fetal response was significantly more common in infants with surgical NEC vs. medical NEC (35.4% vs. 15.3%; p = 0.02). On regression model, infants with multiple placental pathologies (OR 2.16; 95% CI 1.01 - 4.73; p = 0.04) and maternal vascular malperfusion (OR 2.2; 95% CI 1.12 - 4.51; p = 0.02) had higher odds of either medical or surgical NEC than controls. CONCLUSION: Infants with multiple placental lesions, including placental inflammatory and vascular lesions, were at higher risk of medical or surgical NEC in the postnatal period.

Clinical and histopathological correlates of intestinal repair in preterm infants following surgical necrotizing enterocolitis.

OBJECTIVE: We sought to determine the clinical and histopathological factors linked with intestinal repair and its correlation with clinical outcomes in preterm infants following surgical necrotizing enterocolitis (NEC). METHODS: A retrospective study has compared clinical and histopathological characteristics between preterm infants with histopathological reparative changes versus non-reparative changes in resected intestinal tissue following surgical treatment of NEC. Reparative changes were defined as microscopic evidence of neovascularization, increased fibroblasts or myofibroblasts, and epithelial regeneration during histopathological examination of the most affected area of resected intestinal tissue. RESULTS: The infants with reparative changes (53/148) had significantly lower median birth weight (725 [650-963] vs. 920 [690-1320]; p = .018), higher likelihood of patent ductus arteriosus (38/53 [71.7%] vs. 48/95 [50.5%]; p = .012), longer TPN days (99 [56-147] vs. 76.5 [39-112.5]; p = .034), higher CRP levels (7.3 [3.2-13] vs. 2.6 [1.1-7.8]; p = .011) at NEC onset, and more short bowel syndrome (27/53 [54.0%] vs. 28/95 [32.2%]; p = .012). Those with reparative changes also received more Penrose drain therapy (21/53 [39.6%] vs. 14/95 [14.7%]; p = .011) and had a longer median time to laparotomy (108 h [28-216] vs. 24 [12-96]; p = .003). Epithelial regeneration observed in 6/53 (11.3%) infants lagged fibroblast proliferation and neovascularization changes in the submucosa/muscularis intestinal layers. On a multivariable logistic regression model which included histopathological and clinical factors, inflammation with a percentage <25% area involvement, time from NEC diagnosis to surgery, and Apgar score < 6 at 5 min were independently and significantly associated with higher odds reparative changes. CONCLUSION: In neonates with surgical NEC, the histopathological findings in the resected bowel are significantly associated with clinical characteristics, other histopathological findings, and outcomes. The presence of reparative changes consistent with healing is significantly associated with Apgar score, Penrose drain therapy, longer time from NEC diagnosis to surgery, and lower burden of inflammation in the resected bowel tissue in multivariable analyses. Routine histopathological grading of resected bowel and optimal use of Penrose drain therapy warrant further investigation in the care of neonates with surgical NEC.

Clinical impact of severe acute kidney injury on post-operative and brain injury outcomes in preterm infants following surgical necrotizing enterocolitis.

BACKGROUND: To evaluate post-operative outcomes and white matter injury (WMI) using brain MRI at term equivalent in neonates with and without severe acute kidney injury (AKI) following surgical necrotizing enterocolitis (NEC). METHODS: A retrospective cohort study comparing neonates with severe (Stage 2/3) vs. other (no AKI/Stage 1) AKI using KDIGO classification with multivariable models assessing this association in the context of multiple systemic comorbidities. RESULTS: Of 103 neonates with surgical NEC, 60 (58%) had severe AKI. Those with severe AKI had lower birth weight (BW; 715 vs. 950 g; p = .023), more frequently treated with indomethacin (18.3 vs. 2.4%); p = .014), higher CRP levels at 24 h after NEC onset (14.4 [6.4-19.8] vs. 4.8 [1.6-13.4]; p = .005), higher presence of cholestasis (73.3 vs. 51.2%); p = .023), later age of NEC onset (14 vs. 7 d); p = .004), longer length of bowel resected (14.9 vs. 4.3 cm); p = .011), longer post-operative ileus days (14 vs. 9 d); p < .001), longer post-operative days at starting enteral feedings (15 vs. 10 d; p < .001), longer days of attainment of full enteral feedings (75 vs. 44.5 d; p = .008) and longer length of stay (140.5 vs. 94 d; p = .028) compared to those without severe AKI. Compared to infants without AKI by serum creatinine, those with AKI had significantly more cases of white matter abnormality (WMA; 90 vs. 36.6%; p < .001) and retinopathy of prematurity (63.9 vs. 35.3%; p = .017). In addition, the presence of AKI Stage 2 and 3 by serum creatinine was independently associated with higher odds of sustaining severe WMI level on an ordinal scale (OR = 6.2; 95% CI = (1.1-35.5); p = .041). CONCLUSIONS: Neonates with severe AKI following surgical NEC were more likely to experience longer post-operative morbidity and higher WMI by MRI at term.

Gestational age-specific hematological patterns in preterm infants following necrotizing enterocolitis.

OBJECTIVE: To investigate gestational age (GA) specific hematological and transfusion response patterns in preterm infants following necrotizing enterocolitis (NEC). DESIGN: A retrospective study comparing hematological/transfusion information in three GA groups' infants: Group A ≤ 28 weeks. Group B 28-32 weeks, Group C > 32 weeks following necrotizing enterocolitis. RESULTS: Group A infants responded with significantly higher WBC count, thrombocytopenia, higher absolute neutrophil, and higher absolute monocyte and lower absolute lymphocyte counts following NEC onset, received more blood transfusions before NEC onset (59.8 versus 30.0%; p = .007), and had higher odds of surgical NEC (OR 3.39 [95% CI 1.19-10.38]; p = .02) than group C. One unit increase in absolute lymphocyte count on the day, and 24 h following NEC was significantly associated with lower surgical NEC odds than groups C. CONCLUSION: The infant's in-group A had significantly different hematological response patterns following NEC than infants with higher gestational age (groups B and C).

Intestinal Resection is More Likely to be Effective in Necrotizing Enterocolitis Extending to Colon than in Disease Limited to the Small Intestine.

Background: The prognosis in surgical necrotizing enterocolitis (NEC) has focused on the total length of the resected bowel; the relative impact of small intestinal vs colonic resection is not well studied. Objective: We hypothesized that intestinal resections may reduce mortality and length of hospital stay (LOS) more likely in infants who have NEC extending into the colon than in those with disease limited to the small intestine. We also investigated the relationship between gestational maturation and NEC-related mortality. Methods: A retrospective study of 153 patients compared demographic, clinical, and histopathological information in infants who had NEC limited to the small intestine vs disease with colonic involvement. Results: Our 153 infants had a mean (±standard deviation) gestational age of 27.4 ± 3.4 weeks and a birth weight of 987 ± 505 g. NEC was limited to the small intestine in 103 (67.3%) infants and extended into the colon in 50 (32.7%). Infants with small intestinal NEC needed shorter bowel resections of 28 ± 31.9 cm than 42.2 ± 40.7 cm in those with colonic involvement (p = 0.02). The LOS was longer in NEC limited to the small intestine than in disease with colonic lesions (96 ± 88.1 vs 69.7 ± 19.1 days; p <0.05). In small intestinal NEC, mortality decreased to <50% beyond a gestational age (GA) >37 weeks. In contrast, infants with NEC that involved the colon had mortality <50% mortality beyond 27.3 weeks' GA (p = 0.008). Conclusions: Bowel resections may be more likely associated with shorter LOS in surgical NEC that involves both the small bowel and colon, even when longer segments of the gastrointestinal tract are removed, than in disease limited to the small intestine.

Clinical impact of NEC-associated sepsis on outcomes in preterm infants.

OBJECTIVE: To determine risk factors and outcomes of necrotizing enterocolitis (NEC)-associated sepsis in infants with NEC. METHODS: A retrospective review comparing demographic and clinical information in infants with and without NEC-associated sepsis (defined as positive blood culture at the time of NEC onset). RESULTS: A total of 209 infants with medical (n = 98) and surgical NEC (n = 111) had a median gestational age of 27 weeks (IQR 25; 30.5) and a median birth weight of 910 g [IQR 655; 1138]. Fifty of 209 (23.9%) infants had NEC-associated sepsis. Infants with NEC-associated sepsis had lower median GA (26.4 vs. 27.4 weeks; p = 0.01), lower birth weight (745 vs. 930 g; p = 0.009), were more likely mechanically ventilated [p < 0.001], received dopamine [p < 0.001], had more evidence of acute kidney injury [60% vs. 38.4%, p = 0.01], longer postoperative ileus (16 [13.0; 22.0] vs. 12 [8; 16] days; p = 0.006), higher levels of C-reactive protein, lower platelet counts, longer hospitalization compared to infants without NEC-associated sepsis. On multivariate regression, cholestasis was an independent risk factor for NEC-associated sepsis (OR 2.94; 95% CI 1.1-8.8, p = 0.038). CONCLUSION: NEC-associated sepsis was associated with greater hemodynamic support, acute kidney injury, longer postoperative ileus, and hospitalization on bivariate analysis, and cholestasis was associated with higher odds of sepsis on multi regression analysis. IMPACT: NEC-associated sepsis was present in 24% of infants with NEC. Gram-positive bacteria, Gram-negative bacteria, and Candida were found in 15.3%, 10.5%, and 2.8% of cases, respectively. Infants with NEC-associated sepsis had a greater inflammatory response (CRP levels), received more blood transfusion before NEC onset, frequently needed assisted ventilation ionotropic support, and had acute kidney injury after NEC onset. NEC infants with Gram-negative sepsis had higher portal venous gas, received more platelet transfusions before NEC onset, and had higher CRP levels and lower median lymphocyte counts at 24 h after NEC onset than those with Gram-positive sepsis.

Brain injury in preterm infants with surgical necrotizing enterocolitis: clinical and bowel pathological correlates.

BACKGROUND: The objective of this study was to determine the risk factors and outcomes of white matter brain injury (WMBI) on magnetic resonance imaging (MRI) at term-equivalent age in infants with surgical necrotizing enterocolitis (NEC). METHODS: This retrospective study compared clinical/pathological information between infants with and those without WMBI. RESULTS: Out of 69 infants with surgical NEC, 17 (24.6%) had mild WMBI, 13 (18.8%) had moderate WMBI, and six (8.7%) had severe WMBI on the brain MRI. Several clinical factors (gestational age, more red blood cell (RBC) transfusions before NEC onset, pneumoperitoneum, earlier NEC onset age, postoperative ileus, acute kidney injury (AKI) by serum creatinine, postnatal steroids, hospital stay) and histopathological findings (necrosis, hemorrhage) had univariate associations with WMBI. Associations with RBC transfusion (odds ratio (OR) 23.6 [95% confidence interval (CI): 4.73-117.97]; p = 0.0001), age at NEC onset (OR 0.30 [95%CI: 0.11-0.84]; p = 0.021), necrosis (OR 0.10 [95%CI: 0.01-0.90]; p = 0.040), and bowel hemorrhage (OR 7.79 [95%CI: 2.19-27.72]; p = 0.002) persisted in multivariable association with grade 3-4 WMBI. The infants with WMBI had lower mean motor, cognitive, language scores, and higher ophthalmic morbidity at 2 years of age. CONCLUSIONS: The WMBI was most likely associated with earlier NEC onset, higher RBC transfusions, and less necrosis and greater hemorrhage lesions on intestinal pathology in preterm infants with surgical NEC. IMPACT: In preterm infants with surgical NEC, brain MRI showed injury in the white matter in 52%, gray matter in 10%, and cerebellar region in 30%. Preterm infants with severe WMBI (grade 3-4) had less necrosis and greater hemorrhagic lesions on histopathology of the bowel. Preterm infants with WMBI were more likely to have a more severe postoperative course, AKI, and longer length of hospitalization. Neuroprotective strategies to prevent brain injury in preterm infants with surgical NEC are needed with the goal of improving the neurodevelopmental outcomes.

Hematological predictors of mortality in neonates with fulminant necrotizing enterocolitis.

OBJECTIVE: Determine whether hematological and transfusion patterns following, the onset of NEC can identify infants likely to develop fulminant, fatal necrotizing enterocolitis (NEC). DESIGN: Determine hematological predictors of fulminant NEC. RESULTS: Of 336 neonates with NEC, 35 (10%) who developed fulminant NEC were born with higher birth weights and more frequently developed radiologically evident pneumoperitoneumand/or portal venous gas. Following the diagnosis of NEC, these infants were more likely to rapidly develop thrombocytopenia, lymphopenia, neutropenia, and lower total white blood cell counts compared to medical/surgical non-fulminant type. They were also more likely to have received a red blood cell (RBC) transfusion (76.7% vs. 53.1%, p = 0.001) within 48 h after disease onset and platelet transfusion (24.2% vs. 11.7%; p = 0.03) before the onset of NEC. CONCLUSION: Neonates with fulminant NEC frequently developed thrombocytopenia, lymphopenia, neutropenia, and leukopenia, received RBC transfusions after or platelet transfusions before the onset of NEC developed the fulminant disease.

Severe acute kidney injury in neonates with necrotizing enterocolitis: risk factors and outcomes.

BACKGROUND: To study the risk factors and outcomes of severe acute kidney injury (AKI) in neonates with necrotizing enterocolitis. METHODS: Retrospective chart review of 202 neonates with necrotizing enterocolitis (NEC) (Bell stage >IIa) from 2013 to 2018. AKI was defined as per-modified neonatal Kidney Disease: Improving Global Outcomes criteria. Demographic, clinical, and outcome data were compared between neonates without severe AKI (stage 0 and 1 AKI) and those with severe AKI (stage 2 and 3 AKI). RESULTS: Severe AKI occurred in 66/202 (32.6%) of neonates after NEC diagnosis and after 61/104 (58.7%) of surgical NEC diagnoses. On adjusted model, surgical NEC [adjusted odds ratio (aOR) = 30.6; 95% confidence interval (CI) = 8.9, 130.6], outborn [aOR = 3.9; 95% CI = 1.54, 11.0], exposure to antenatal steroids [aOR = 3.0; 95% CI = 1.1, 8.9], and positive blood culture sepsis [aOR = 3.5; 95% CI = 1.3, 10.0] had increased odds for severe AKI. Those with severe AKI required longer hospitalization [124 days (interquartile range (IQR) 88-187) vs. 82 days (IQR 42-126), p < 0.001]. CONCLUSIONS: Severe AKI is common in neonates with NEC who require surgical intervention, are outborn, have positive blood culture sepsis, and receive antenatal steroids. Severe AKI is associated with a significantly longer length of hospitalization. IMPACT: Neonates with NEC, who are transferred from outside hospitals, require surgical NEC management, and/or have a positive blood culture at NEC onset are at the highest odds for severe (stages 2 and 3) AKI. Assessment of urine output is important for patients with NEC. Without it, 11% of those with severe AKI would have been misdiagnosed using serum creatinine alone. Kidney-protective strategies in the pre-, peri-, and postoperative period may improve the morbidity and mortality associated with severe AKI in neonates with NEC.