What Are the Presenting Problems of Staphylococcus in Neonates?

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Patient Presentation
A 25-day-old female was transferred to a regional children’s hospital after a 3 day history of right submandibular swelling.
Originally she was seen again by her local pediatrician who gave her 1 dose of ceftriaxone and then began Amoxicillin-Clavulanic acid twice a day.
She was re-seen the following day without any change in the size of the mass and was seen in the morning of the next day.
The mother noted that the swelling had increased in size this morning and now had overlying reddening of the skin.
The infant also seemed to be fussier but had no problems feeding or breathing. The infant was begun on Vancomycin and Unasyn for suspected Methicilln-resistent Staphylococcus aureus (MRSA).
A computerized tomography of the neck showed a 2.6 cm lymph node with a necrotic center.

The past medical history showed a full-term infant without prenatal or natal complications. She had seen the pediatrician at 5 days and 10 days of life and was growing well. The family history was negative for underlying immune diseases. The review of systems was negative.
The pertinent physical exam showed a very fussy female with normal vital signs except for a temperature of 38.1° Celsius.
HEENT was normal except for a 4×3 cm right-sided mass that was hard and appeared fixed to underlying tissues. It was underneath the mandible and spread toward the clavicle and was tender to palpation.
No other lymph nodes were palpated including inguinal, axillary and supraclavicular nodes.
Lungs were clear and no increased work of breathing was noted. Abdomen was normal including no hepatosplenomegaly.
Skin had no other erythema or rashes. The rest of the examination was normal.

The work-up included a white blood count of 14.6 x 1000/mm2 with increased neutrophils and monocytes. Her C-reactive protein was 0.9 mg/dl (normal < 0.5)

The diagnosis of a right submandibular lymph node abscess was made. The patient’s clinical course revealed her continuing on the intravenous antibiotics for the next two days. She did not have significant resolution so she was taken to the operating room where anincision and drainage of the abscess was performed with drain placement.
She had significant improvement by the following day and the drain was removed.
She was discharged later that night and was completely well at a follow-up two weeks later by the otolaryngologist.

Discussion
Staphylococcus sp. are gram-positive, catalase-positive cocci that cluster when viewed microscopically. There are 17 species indigenous to humans and 13 colonize humans. Staphylococcus aureus is the only species that produces coagulase.
Staphylococcus sp. can be found in almost any environment including high salt, low oxygen, high heat and low moisture. Coagulase-negative Staphylococcus sp. are so common that newborn infants are colonized by 2-4 days of life usually with S. epidermidis and S. haemolyticus.

Staphylococcus aureus produces many infections especially pneumonia and surgical wound infections. Humans can be colonized with it especially in mucous membranes and the perineum and axilla.
Those with nasal carriage can also transiently carry the organism on their hands, thus increasing the risk of transmission to others. MRSA is resistant to all beta-lactamase antibiotics and possibly to other antibiotics in other classes.
MRSA is common in hospitalized and institutionalized patients and unfortunately is spreading to more communities. The most common comm
y-acquired MRSA infections are skin and soft tissue infections but pneumonia and invasive disease does occur.
Community MRSA strains are often still susceptible to common antibiotics such as doxycycline, clindamycin, gentamicin, and trimethoprim-sulfamethoxazole but local sensitivities vary between communities.

Learning Point
A nursery outbreak of Staphylococcus was first reported in 1904. Since then, epidemic waves occur on ~20 year cycles (with the background of sporadic and endemic infections).
Neonates especially those in intensive care units, have a higher rate of infection than other infants. Data has shown that smaller, more premature infants and those with instrumentation also have higher rates of infection.
Coagulase-negative Staphylococcus is also known to co-infect with Candida sp..

Common presentations of Staphlococcal infections in neonates include:

  • Bacteremia** and sepsis
  • Skin and soft tissue infections** – skin, wound, abscess, lymphadenitis
  • Bone and joint – osteomyelitis, arthritis
  • Endocarditis and portal vein thrombosis
  • Meningitis
  • Peritonitis – abdominal abscess
  • Pneumonia – empyema, lung abscess
  • Urinary tract infection

** most common

Treatment for serious methicillin-sensitive Staphylococcus aureus (MSSA) usually requires intranvenous therapy with at least a beta-lactam antibiotic such as nafcillin or oxacillin as most S. aureus strains are resistant to pencillin and ampicillin.
Vancomycin is a commonly used alternative but judicious use is needed to help stem emergence of vancomycin-resistant strains of MSSA. Specific choice of antibiotics depends on local sensitivities and the clinical scenario.
Consultation with an infectious disease expert may be necessary.

Scrupulous attention to hand-hygiene practices are necessary to prevent spread particularly within institutions. Eradication of nasal carriage is sometimes attempted but is difficult to actually do; it is not routinely advised.
Other treatments such as catheter removals, dressing changes, IVIG and antibody administration are also used in some cases.

Questions for Further Discussion
1. What are your local MRSA versus MSSA sensitivity patterns?
2. What are the rates of neonatal Staphylococcus sp. infections in your local nursery?

Related Cases

    Specialty: General Pediatrics | Infectious Diseases |Otolaryngology

    To Learn More
    To view pediatric review articles on this topic from the past year check PubMed.

    Evidence-based medicine information on this topic can be found at SearchingPediatrics.com, the National Guideline Clearinghouse and the Cochrane Database of Systematic Reviews.

    Information prescriptions for patients can be found at MedlinePlus for these topics: Staphlococcal Infections and MRSA.

    To view current news articles on this topic check Google News.

    To view images related to this topic check Google Images.

    Healy CM, Palazzi DL, Edwards MS, Campbell JR, Baker CJ. Features of invasive staphylococcal disease in neonates. Pediatrics. 2004 Oct;114(4):953-61.

    Fortunov RM, Hulten KG, Hammerman WA, Mason EO, Jr, and Kaplan SL. Community-Acquired Staphylococcus aureus Infections in Term and Near-Term Previously Healthy Neonates. Pediatrics. 2006;118;874-881.

    Venkatesh MP, Placencia F, Weisman LE. Coagulase-negative staphylococcal infections in the neonate and child: an update. Semin Pediatr Infect Dis. 2006 Jul;17(3):120-7.

    American Academy of Pediatrics. Staphlococcal Infections, In Pickering LD, Baker CJ, Long SS, McMillan JA, eds. Red Book: 2006 Report of the Committee on Infectious Diseases. 27th edit. Elk Grove Village, IL: American Academy of Pediatrics; 2006;598-610.

    ACGME Competencies Highlighted by Case

  • Patient Care
    1. When interacting with patients and their families, the health care professional communicates effectively and demonstrates caring and respectful behaviors.
    2. Essential and accurate information about the patients’ is gathered.
    3. Informed decisions about diagnostic and therapeutic interventions based on patient information and preferences, up-to-date scientific evidence, and clinical judgment is made.
    4. Patient management plans are developed and carried out.
    5. Patients and their families are counseled and educated.
    7. All medical and invasive procedures considered essential for the area of practice are competently performed.
    8. Health care services aimed at preventing health problems or maintaining health are provided.
    9. Patient-focused care is provided by working with health care professionals, including those from other disciplines.

  • Medical Knowledge
    10. An investigatory and analytic thinking approach to the clinical situation is demonstrated.
    11. Basic and clinically supportive sciences appropriate to their discipline are known and applied.

  • Practice Based Learning and Improvement
    13. Information about other populations of patients, especially the larger population from which this patient is drawn, is obtained and used.

  • Systems Based Practice
    24. Cost-effective health care and resource allocation that does not compromise quality of care is practiced.
    25. Quality patient care and assisting patients in dealing with system complexities is advocated.
    26. Partnering with health care managers and health care providers to assess, coordinate, and improve health care and how these activities can affect system performance are known.

    Author
    Donna M. D’Alessandro, MD
    Professor of Pediatrics, University of Iowa Children’s Hospital

Published