The present study concluded that absent signs of clinical infection, breastfeeding should continue normally when mother and baby are diagnosed with Red Diaper Syndrome caused by Serratia marcescens, an opportunistic bacteria. The study in Breastfeeding Medicine

The article entitled, "Serratia marcescens Colonization Causing Pink Breast Milk and Pink Diapers: A Case Report and Literature Review," is co-authored by Laura Quinn, Elizabeth Matthews, Ann Kellams, Debbie-Ann Shirley from the University of Virginia School of Medicine (Charlottesville, VA) and Melody Ailsworth, Richeson Drive Pediatrics (Lynchburg, VA).

Serratia marcescens is an opportunistic pathogen and common cause of infectious outbreaks in pediatric units, leading to both significant morbidity and mortality in immunocompromised hosts.

Environmental and some clinical strains may produce a characteristic red pigment, prodigiosin. Colonization can hence turn breast milk and fecally-soiled diapers pink, which can lead otherwise unaffected patients to present to their physicians and also interrupt breastfeeding

Widely prevalent throughout the environment, Serratia marcescens is an opportunistic bacteria associated with hospital-acquired infections in critically ill patients. Our understanding of its pathogenicity has evolved over time.

Treatment of Red diaper syndrome

The unique ability of the microorganism to create red pigment was first described in 1819 when Italian pharmacist Bartolomeo Bizio demonstrated that the “blood” miraculously thought to appear on stored polenta was indeed due to the presence of a living organism.

The study looked at the case of an 11-week-old infant being treated for fussiness and whose soiled diapers and clothing turned pink. The nursing mother also reported pink nursing pads.

Providers evaluating mother-infant dyads with S. marcescens colonization causing pink milk or pink infant soiled diapers should assess for manifestations of systemic infection. In the absence of evidence of clinical infection, expectant management is appropriate and continued breastfeeding can be supported.

Additionally, similar studies involving nine other infants were also reviewed. The authors concluded that there is not enough evidence to support treatment of the bacteria in otherwise healthy babies and mothers should be reassured that they can continue with breastfeeding in these circumstances.

"Knowledge that this bacteria is generally not pathological and clinical judgment should thus be the physician's guide," says Arthur I. Eidelman, MD, Editor-in-Chief of Breastfeeding Medicine.