Bloody Stools in a 3-Day-Old Term Infant

Causes of bloody stools in neonates: a case series report

BACKGROUND

Bloody stools in a neonate may stand for a spectrum of conditions ranging from benign to life-threatening. It is critical to detect the cases that have significant underlying pathology, especially those which require urgent surgical intervention. Previous studies always focused on one particular disease related to bloody stools in neonates, or the study only involved a small number of cases. This study aimed to investigate the common causes of bloody stools in neonates.

METHODS

This retrospective cohort study included the neonates admitted to our institution due to "bloody stools" over a 5-year period. We compared the differences among patients' characteristics, feeding choice, underlying diseases, and operation rate between preterm and term neonates.

RESULTS

A total of 300 patients were included, accounting for 1.1% of the total neonatal admissions. The overall rate of exclusive breastfeeding was 28.0%. The most common underlying causes for bloody stools were: cow's milk protein allergy (CMPA, 53.3%), swallowed blood syndrome (10.0%), viral enteritis (9.7%), necrotizing enterocolitis (NEC) > stage II (8.3%), non-specific enteritis (7.3%), and anal fissure (5.0%). The median [interquartile range (IQR)] onset age for bloody stools for all infants was 12 [3-22] days after birth. Preterm neonates had a lower rate of exclusive breastfeeding (P=0.844), higher incidence of NEC > stage II (P=0.014), later bloody stools onset age (P<0.001), and longer length of hospital stay than term neonates (P<0.001). For neonates with NEC, those with bottle-fed had an earlier onset age for bloody stools than those with breast-fed (P=0.027). Only 1.7% (n=5) required surgery (2 stage III NEC, 1 post-NEC stricture, and 2 volvuli). Survival at hospital discharge was 100%.

CONCLUSIONS

Bloody stools in neonates is generally a benign, self-limiting disorder, not related to surgical conditions. The overall operation rate among neonates with bloody stools was only 1.7%. CMPA and NEC were the most common underlying non-surgical and surgical diseases, respectively, for neonates with bloody stools. Feeding choice is related to bloody stools in neonates, policies and strategies to support breastfeeding should be strengthened in the future.

Clinical significance of positive fecal occult blood test in neonates

The fecal occult blood test (FOBT) is a screening tool for hematochezia. This study aims to summarize the clinical features associated with a positive FOBT in neonates and to explore some clues for the underlying causes. Combination with other clinical information, identifying the possible etiology is more likely and could be useful for choosing an effective therapeutic strategy. The medical records of 282 neonates with positive FOBTs from January 1 to July 31, 2016, were collected and retrospectively analyzed. The total incidence rate of FOBT positivity in neonates was 6.2%. Among these patients, 71 (25.2%) neonates had false-positive FOBTs, whereas 211 (74.8%) neonates had intraintestinal sources of hematochezia. Necrotizing enterocolitis (NEC, 20.9%), structural abnormalities of gastrointestinal tract (SAGT, 12.4%), and suspected food allergy (sFA, 10.6%) were the most common causes of neonatal hematochezia. It indicated that FOBT-positive neonates with NEC were more likely to suffer due to a younger gestational age, lower birth weight, and lower weight on admission than the neonates with other conditions. The proportions of neonates with bloody stool (90.0%) and diarrhea (63.3%) in the sFA group were markedly higher than those in the other groups. However, in the SAGT group, emesis (94.3%) and abdominal distension (80.0%) were evidently higher, usually accompanied by a relatively poor response (60.0%) and weakened bowel sounds (48.6%). Furthermore, the higher incidences of poor response (72.1%), abdominal distension (71.2%), bloody stools (64.4%), and weakened bowel sounds (62.7%) were observed in the NEC group. Due to the complicated etiology associated with a positive FOBT, the analyzed indexes were combined with other clinical features to identify the likely causes of neonatal hematochezia. Because NEC, sFA and SAGT show similar clinical manifestations and can occasionally transform into each other, close and frequent observation is crucial for timely intervention to achieve a better prognosis. Although it failed to provide an early warning of severe disease through FOBT, and the early intervention for FOBT might not decrease NEC, sFA, structural bowel injuries, or any other complications, newborn FOBT positive reminds medical staff to be alert to the related diseases including NEC, SAGT and sFA, by closer observation and follow-up.