The infant did not show signs of illness; her mother experienced a routine pregnancy and prenatal lab test results were normal. What is the diagnosis?
A female infant aged 2 days had been born at term, appearing healthy and breastfeeding well without signs of illness. She had an episode of coffee ground emesis while admitted to the newborn nursery (Figure 1). She had been born via uncomplicated spontaneous vaginal delivery to a mother following a routine pregnancy and good prenatal care with normal prenatal lab test results and no substance use. Apgar scores were 8 and 9; no resuscitation was needed. The infant had received intramuscular phytonadione after birth and had no known risk factors for hemorrhage or upper gastrointestinal (GI) bleeding, including no delivery trauma or signs of infection. The infant had passed normal meconium stools without melena or hematochezia.
The neonate’s vital signs after the episode of emesis were within normal limits. Physical examination revealed a well-developed neonate who was awake and in no distress. Her anterior fontanelle was open, soft, and flat. Her head was normocephalic and atraumatic. Her conjunctivae were clear without hemorrhage. Nares and oropharynx were clear without visible source of bleeding. Cardiovascular exam revealed no murmur or tachycardia. Her lungs were clear and she was not tachypneic. Her abdomen was soft with normoactive bowel sounds, no organomegaly, and no distention. Skin examination showed no bruising, petechiae, or jaundice. Given her well appearance, laboratory examination or other neonatal diagnosis or therapeutic intervention was not immediately pursued.
Maternal breast exam revealed soft breasts with everted nipples without erythema, cracks, trauma, or bleeding.
The differential diagnosis for a neonate with hematemesis—either fresh blood or coffee ground emesis—includes sepsis, coagulopathy, gastritis, vitamin K deficiency, trauma, and ingestion from a maternal source, and can be seen in the Table.1,2 An upper GI bleed in the neonate is rare, and most commonly the neonate is critically ill.1 This infant’s overall well appearance and benign exam were reassuring and did not support a true upper GI bleed as a diagnosis. Despite the lack of obvious maternal nipple bleeding, cracks, or trauma, the pediatric team asked the patient’s mother to pump her breast milk for examination before pursuing additional work-up in the neonate. As seen in Figure 2, unilateral bloody milk was expressed, suggesting a diagnosis of swallowed maternal blood during breastfeeding rather than pathology within the infant. Bloody nipple discharge late in pregnancy or post partum or during lactation can be due to several conditions: rusty pipe syndrome (RPS), mastitis, cracked nipples, trauma, and papillary breast disease including intraductal papilloma and papillary carcinoma.3 In this case, the lack of other breast pathology or obviously bloody nipple discharge suggested atypical RPS as a diagnosis.
RPS refers to the uncommon and benign condition where there is typically painless nipple discharge, and maternal colostrum or breast milk becomes blood-tinged in the absence of nipple injury through a process internal to the breast.4 This syndrome is usually bilateral.4,5 It is so named because the color of the breast milk is similar to water coming out of a rusty pipe. It more commonly occurs in primiparous women, and the bleeding is painless.5,6 The mechanism through which erythrocytes end up in the colostrum or milk is related to rapid vascularization during pregnancy followed by fragile blood vessels breaking during stage II lactogenesis.4-6 The resulting milk color can range from bright red to pink to black or brown.4 It typically occurs during the first few days of lactation and resolves spontaneously within 7 days.6 This is in contrast to papillary breast disease, which typically results in more persistent bloody discharge.3
RPS can be discovered when milk is collected through pumping or when an infant has blood-stained spit-up, or when there is maternal discolored nipple discharge. Maternal breast examination should be performed in these cases in addition to examination of the infant.4 The diagnosis is supported by the history, expression of bloody milk, and benign examinations of the infant, and the breastfeeding mother typically has a blood-tinged nipple discharge.5 If the origin of the blood is unclear, the Apt-Downey test may be performed to distinguish maternal from fetal blood. Further investigation may occur to rule out pathologic conditions.5 Cytologic examination of the milk may be undertaken for evaluation of malignant cells, especially in the case of history of maternal breast disease.4,5 Ultrasonography of the breast to evaluate for mass or abnormality may also be considered.5,6 RPS requires no treatment in either the breastfeeding parent or the infant.4 Breastfeeding may continue without interruption and the stained milk is safe for the infant to consume.4 Breastfeeding provides many health benefits to the infant and parent, and exclusive breastfeeding is the recommended mode of infant feeding for the first 6 months of life.7 Prompt evaluation and guidance to patients is important to reduce barriers to breastfeeding and disruption to health benefits. For families with concern regarding the safety of providing blood-tinged milk, highlighting the extra iron that the infant will receive may be helpful.
Mastitis or traumatic injury to the breast or nipple from a breast pump or poorly latched infant can also lead to ingestion of maternal blood and represents a mechanism of newborn hematemesis distinct from RPS. This bleeding is usually painful to the mother, in contrast to RPS.5
The patient continued to breastfeed well on demand. She had no further episodes of bright red or coffee ground emesis. She had no development of illness including fever or lethargy. Neonatal weight loss remained within acceptable parameters, and she continued to produce appropriate urine and stool output. She was discharged home with routine follow-up with her pediatrician.
1. Baker RD, Baker SS. Gastrointestinal bleeds. Pediatr Rev. 2021;42(10):546-557. doi:10.1542/pir.2020-000554
2. Romano C, Oliva S, Martellossi S, et al. Pediatric gastrointestinal bleeding: perspectives from the Italian Society of Pediatric Gastroenterology. World J Gastroenterol. 2017;23(8):1328-1337. doi:10.3748/wjg.v23.i8.1328
3. Mitchell KB, Johnson HM, Eglash A; Academy of Breastfeeding Medicine. ABM clinical protocol #30: breast masses, breast complaints, and diagnostic breast imaging in the lactating woman. Breastfeeding Med. 2019;14(4):208-214. doi:10.1089/bfm.2019.29124.kjm
4. Wszolek KM, Nowek A, Odor A, Piet M, Wilczak M. Rusty pipe syndrome. Safety of breastfeeding. Ginekol Pol. 2021;92(12):902-904. doi:10.5603/GP.a2021.0188
5. Kural B, Sapmaz S. Rusty pipe syndrome and review of literature. Breastfeed Med. 2020;15(9):595-597. doi:10.1089/bfm.2020.0055