Staphylococcus Aureus Carrier Status in Breastfeeding Mothers and Infants and the Risk of Lactation Mastitis

Staphylococcus Aureus Carrier Status in Breastfeeding Mothers and Infants and the Risk of Lactation Mastitis: A Large Prospective Study

Lactation (breastfeeding) mastitis is an acute infection of the milk ducts of the breastfeeding woman. Staphylococcus aureus (S. aureus) is the infectious germ most commonly associated with lactation mastitis. Twenty percent of the general population are carriers of Staphylococcus aureus, which means that they carry the infectious germ but do not become ill from it. It has been suggested that mothers who are carriers of S. aureus in their nostril may be at an increased risk of developing lactational mastitis, however; this has not been clinical proven.

We are studying the relationship between S. aureus carrier status of breastfeeding mothers and infants and the risk of developing lactational mastitis. Additionally, we are collecting questionnaire data in an attempt to better define factors predisposing women to lactation mastitis.

Study Overview

• Status: Completed
• Conditions: Staphylococcus Aureus; Staphylococcal Infections; Mastitis

Detailed Description

Lactation mastitis is an acute inflammation of the interlobular connective tissue within the mammary gland of a breastfeeding woman. It is a relatively common condition that causes pain and worry, and can lead to restriction in activity and increased risk of early weaning from breastfeeding. Staphylococcus aureus is the infectious agent most commonly implicated in lactation mastitis.

It is well established that the anterior nares are the primary reservoir of S. aureus in humans and that approximately 20% of healthy individuals are "persistent carriers" of the organism. Carriage of Staphylococcus aureus has been identified as a significant risk factor for the development of infection including surgical wound infections. It has been suggested that maternal and infant nasal carriage of S. aureus may be associated with an increased risk of breast infection during lactation.

We propose to prospectively study the relationship between the S. aureus carrier status of 500 healthy breastfeeding dyads and the rate of the subsequent development of lactational mastitis. Carrier status of mothers and infants will be determined through two nasal swabbings performed in the early post-partum period. The swabs will be analyzed with both traditional culture and through Polymerase chain reaction (PCR) amplification analysis. Mastitis rate will be determined via serial follow-up telephone interviews during the first two months post-partum.

• Study Type: Observational
• Enrollment (Actual): 557

Contacts and Locations

Study Locations

• United States
  • New York
    • Syracuse, New York, United States, 13210
      • SUNY Upstate Medical University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: Female

• Sampling Method: Probability Sample

Study Population

We will be enrolling 500 dyads (mother and newborn infant pairs) into the study over approximately a three year period. Mothers will be age 18 years or older.

Description

Inclusion Criteria:

• Mother must plan to breastfeed exclusively for at least two months
• Mother must be 18 years or older.
• Mother must speak English and capable of giving informed consent
• Must be the delivery of a term (37 weeks or more), singleton live infant.
• Mother must be within post-partum day zero to three-status post delivery
• Both mother and infant generally healthy without disease known to cause significant immune dysfunction or known to be associated with abnormally high carriage rates of S. aureus such as HIV-positive status or AIDS, Type I Diabetes Mellitus, ongoing need for hemodialysis or chronic steroid use, or receiving either chemotherapy/radiation treatment for malignancy?
• Must have the ability to communicate via phone for follow up assessments.

Exclusion Criteria:

• Does not have the ability to drop off the second set of cultures.

Study Plan

How is the study designed?

Design Details

• Observational Models: Cohort
• Time Perspectives: Prospective

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Our primary objective is to determine the association of nasal carriage of S. aureus in breastfeeding mothers and infants with the rate development of mastitis in the mothers.	Culture results will be unblinded at the end of the study.

Secondary Outcome Measures

Outcome Measure	Time Frame
Secondary objective will be to document the S. aureus carriage rate, including methicillin-resistant Staphylococcus aureus (MRSA), in early post-partum period and to assess the relationship between S. aureus carrier status of the mother and the infant.	Culture results will be unblinded at the end of the study.

Collaborators and Investigators

• Sponsor: State University of New York - Upstate Medical University
• Investigators: Principal Investigator: Jayne R Charlamb, MD, IBCLC, State University of New York - Upstate Medical University

Study record dates

Study Major Dates

• Study Start: August 1, 2006
• Primary Completion (Actual): August 1, 2009
• Study Completion (Actual): December 1, 2009

Study Registration Dates

• First Submitted: February 13, 2008
• First Submitted That Met QC Criteria: February 21, 2008
• First Posted (Estimate): February 22, 2008

Study Record Updates

• Last Update Posted (Estimate): June 2, 2015
• Last Update Submitted That Met QC Criteria: May 29, 2015
• Last Verified: May 1, 2015

More Information

Terms related to this study

• Keywords: Staphylococcus aureus; Breastfeeding; Lactational Mastitis; Polymerase Chain Reaction (PCR) amplification analysis; staphylococcal infections; staphylococcal Carrier State
• Additional Relevant MeSH Terms: Skin Diseases; Infections; Breast Diseases; Bacterial Infections; Bacterial Infections and Mycoses; Gram-Positive Bacterial Infections; Pregnancy Complications; Puerperal Disorders; Staphylococcal Infections; Mastitis
• Other Study ID Numbers: 5395