Blood Streaks in Stool

I have a two month-old baby with blood streaks in the stool – what should I do?

Do I have to worry about NEC in this baby?
The younger the baby the more you have to worry. However, if the physical examination is normal and the baby is thriving, it is a very unlikely diagnosis. I usually recommend a plain abdominal film to look for pneumatosis intestinalis in babies under 1 month.

What other disorders do I need to consider in a thriving baby who starts having blood streaks in the stool?
Infection with campylobacter or ameba might cause blood streaks in a healthy baby. Rotavirus occasionally causes bleeding in babies too. Anal stenosis often presents as a healthy baby who strains and passes stools explosively enough to result in blood streaks. Allergic colitis (some people call it cow’s milk colitis) is by far the most likely diagnosis. Rarely, colitis is the first manifestation of immune deficiency.

What tests should I do?;
Under 1 month get a plain abdominal film, a CBC, a stool culture and examination for O + P and rotavirus. Do a good PE including a digital rectal exam for stenosis.

Does this baby need a flexible sigmoidoscopy?
Although the sigmoidoscopy findings in a baby with allergic colitis are characteristic, sigmoidoscopy is not necessary. You are not going to change your management based on the findings.  

Does this baby need to see a gastroenterologist?
No, this is a common problem in healthy infants and education of the parents is the most pressing need.  Read the handout on Allergic Colitis.

How do I treat this baby?
There are several options. If the baby is happy and thriving and not overly fussy with stooling, in most circumstances nothing need be done. The problem will resolve without treatment by 6-9 months of age as the baby’s immune system changes to the adult pattern. These infants may need supplementation with iron. If the baby is breast fed, having the mother observe a strict milk protein free diet may make the blood streaks disappear. Maternal diet restriction is not 100% effective. Do not tell the mother to further restrict her diet beyond milk and soy. It will not be likely to help and will be very hard on the breast feeding mom. In the bottle fed baby, or in the breast fed baby who fails the first step, hypoallergenic (not a soy) formula can be helpful and results in prompt resolution of the blood. If the gross blood disappears, the occult blood in stool will remain positive in the majority of babies. This rarely results in iron deficiency or anemia. Occasionally I use probiotics with good effect.

Are there any long term consequences of this problem?
There may be other manifestations of atopy later such as eczema. I have occasionally observed that if the colitis is severe, the baby may later have trouble with constipation. There is no risk of malignancy or of inflammatory bowel disease.

How long do we restrict the mother’s or the baby’s diet?
There aren’t evidence-based guidelines, but most babies can successfully be returned to a regular diet by 6-9 months of age.

How to monitor?
Clinical monitoring is all that is needed. You do not have to do allergy testing or monitor blood in the stool. A follow up CBC and reticulocyte count may be helpful to determine whether iron deficiency has developed.