An Outbreak of Serratia marcescens on the Neonatal Unit: Description and Investigations

Chemsi M¹, Hamid H^1*, Houari S¹, Zerouali K², Lehlimi M¹, Ouhadous M³, Habzi A¹ and Benomar S¹

¹Intensive Care Unit and Neonatal, Hospital of Children Abderrahim ELHarouchi- Casablanca, Morocco

²Bacteriology Laboratoire, Ibn Rochd Hospital-Casablanca, Morocco

³Committee against Nosocomial Infections, Morocco

Corresponding Author:

H Hamid
Faculty of Medicine and Pharmacy of Casablanca,
Children's Hospital Abderrahim Harrouchi of Casablanca, Morocco
Tel: (212)-661800621
E-mail: hamid.hanane2013@gmail.com

Received Date: December 28, 2015; Accepted Date: November 21, 2016; Published Date: November 24, 2016

Citation: Chemsi M, Hamid H, Houari S, Zerouali K, Lehlimi M, et al. (2016) An Outbreak of Serratia marcescens on the Neonatal Unit: Description and Investigations. J Infect Dis Ther 4:306. doi: 10.4172/2332-0877.1000306

Copyright: © 2016 Chemsi M, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

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Abstract

In september 2013, an outbreak of Serratiamarcescens infection occured in the neonatal intensive care unit of children’s hospital Abderrahim Harrouchi in Casablanca. Rapid microbiological investigation lead to identify nine cases of S. marcescens sepsis.The environemental investigation didn’t detect S.marcescens. Strict hygiene measures were lead to early interruption of the outbreak, without reccurences to this date still.

Keywords

Serratia marcescens; Neonatal infection; Outbreak

Introduction

Serratia marcescens is an Enterobacteriaceae opportunistic gram negative, nosocomial pathogen [1].

Several outbreaks of Serratia marcescens in neonatal intensive care unit (NICU) were documented in recent years, causing potentially fatal sepsis, meningitis or pneumoniae in very premature or low birth weight neonates with mortality rates as high as 44% [2,3].

Normally, S. marcescens is not a part of the intestinal bacterial flora of neonates [4].

This bacterium may be transmitted to neonates through feeding, contaminated antiseptics and breast pumps and it can be spread via contact with patient [5].

The objective of this study is to identify the clinical and epidemiological characteristics of S. marcescens infections, and propose an urgent management strategy to control the outbreak.

Patients and Methods

Retrospective study of the cases of Serratiamarcescens outbreaks for a period of one month from September to October 2013 in newborns aged between 0-28days in neonatal unit of Abderrahim El Harrouchi’s hospital in Casablanca.

Results

Nine cases of nosocomial infection of Serratia marcescens were registered (7 inborn and 2 out born). The breakdown by gender in our series shows: six girls and three boys, four of whom were premature, three newborn weighed less than 2000 g. The reason for hospitalization was respiratory distress in 8 cases and an anoxic ischemic encephalopathy in one case. Seven neonates were receiving antibiotics (3rd generation cephalosporins). The average time of onset of nosocomial infection was 5 days +/- 2,16.

The Clinical presentation was a septic shock in 5 cases, neurological signs in 2 newborn, a failure of extubation in 2 cases (Table 1), and biologically a significant increasing C-reactive protein (CRP) values in all cases.

Table 1: Clinical presentation of nosocomial infection of S. marcescens .

The bacteremia was found in all patients associated with two meningeal locations. Blood cultures in all cases grew S. marcescens fully susceptible to imipenem, amikacin and ciprofloxacin (Table 2). All our patients were treated with imipenem and amikacin in all cases and ciproxin in both case of meningeal location. Five neonates with clinical signs of sepsis died, leading to a mortality rate of 54%.

Table 2: Susceptibility to antibiotics of Serratia marcescens.

Some days after neonates became symptomatic, extensive environemental microbiological investigations started. Swabs were taken from numerous surfaces, including walls, floors with their edges and corners, doors and door handles, shelves, benches, hoods, sinks, cradles and ventilators, stethoscopes and other personal medical devices. No common point source was identified, strict hygiene mesures lead to early interruption of the outbreak, without recurrences to this date. (possible sources were disposed and renewed, including parenteral nutrition, disinfectants, soaps and soap dispensers, cotton and tissues, other hygienic measures were taken, such as hand washing with alcohol based solutions at all sites in the ward, and using gloves when assisting and caring for neonates) (Table 3).

Table 3: Clinical characteristics and culture results of the nine infants infected with serratia marcescens.

Discussion

Serratia marcescens is an important nosocomial pathogen, especially in neonatal intensive care units (NICU) 11-15%, and it may causes serious infections, including bacteremia (42%), pneumonia (13%), urinary tract infections (8%) and meningitis (7%), with significant morbidity and mortality rate among newborns (44%) [6,7].

Risk factors for acquisition of nosocomial infections in NICUs are low birth weight, long duration of hospitalization and receiving of critical care [8].

In an outbreak S. marcescens , extensive environmental microbiological investigations are needed to identify sources and reservoirs [2].

Previous publications have reported various sources of contamination such as breast pumps [5], plastic bottles used for umbilical irrigation [9], scalp vein needles [10], soap dispensers [11] or nail brushes [12], but no source was identified in our study.

Reported morbidity and mortality rates associated with S. marcescens outbreaks vary. During an outbreak in a French maternity hospital, only one newborn developed bacteremia and colonization was revealed in the stool samples obtained from 36 newborn [6].

In a report by Halle et al. [13], 27 infants in an NICU were involved in an outbreak, 14 of these infants developed septicemia and/or meningitis, 11 of whom died. In our study, we observed 5 cases of septicemia with fatal outcomes.

Under such circumstances, strict measures such as relocating nurses, closure of wards to new admissions and even temporary total closures of NICU were necessary to contain the spread of microorganism [7,14].

Conclusion

This report serves as reminder of the importance to keep up hygiene precautions at any time specifically in high risk settings such as a NICU.

References

1. Van Houdt R, Givskov M, Michiels CW (2007) Quorum sensing in Serratia. FEMS Microbiol Rev 31: 407-424.
2. Voelz A, Müller A, Gillen J, Le C, Dresbach T, et al. (2010) Outbreaks of Serratia marcescens in neonatal and pediatric intensive care units: clinical aspects, risk factors and management. Int J Hyg Environ Health 213: 79-87.
3. Anderson B, Nicholas S, Sprague B, Campos J, Short B, et al. (2008) Molecular and descriptive epidemiologyof multidrugresistant Enterobacteriaceae in hospitalized infants. Infect Control Hosp Epidemiol29:250-255.
4. Almuneef MA, Baltimore RS, Farrel PA, Reagan-Cirincione P, Dembry LM (2001) Molecular typing demonstrating transmission of gram-negative rods in a neonatal intensive care unit in the absence of a recognized epidemic. Clin Infect Dis 32: 220-227.
5. Gransden WR, Webster M, French GL, Phillips I (1986) An outbreak of Serratia marcescens transmitted by contaminated breast pumps in a special care baby unit. J Hosp Infect 7:149-154.
6. Berthelot P, Grattard F, Amerger C, Frery MC, Lucht F, et al. (1999) Investigation of a nosocomial outbreak due to Serratia marcescens in a maternity hospital. Infect Control Hosp Epidemiol 20:233-236.
7. Fleisch F, Zimmermann-Baer U, Zbinden R, Bischoff G, ArlettazR, et al. (2002) Three Consecutive Outbreaks of Serratia marcescens in a Neonatal Intensive Care Unit. Clin Infect Dis34:767-773.
8. Gaynes RP, Edwards JR, Jarvis WR, Culver DH, Tolson JS, et al. (1996) Nosocomial infections among neonates in high-risk nurseries in the United States. National Nosocomial Infections Surveillance System. Pediatrics 98:357-361.
9. McCormack RC, Kunin CM (1966) Control of a single source nursery epidemic due to Serratia marcescens. Pediatrics 37: 750-755.
10. Stamm WE, Kolff CA, Dones EM, Javariz R, Anderson RL, et al. (1976) A nursery outbreak caused by Serratia marcescens e scalp vein needles as a portal of entry. J Pediatr 89: 96-99.
11. Polilli E, Parruti G, Fazii P, D'Antonio D, Palmieri D, et al. (2011) Rapidly controlled outbreak of Serratia marcescens infection/colonisations in a Neonatal intensive care unit,Pescara General Hospital, Pescara, Italy,April 2011. Euro Surveill16: 19892.
12. Anagnostakis D, Fitsialos J, Koutsia C, Messaritakis J, Matsaniotis N (1981) A nursery outbreak of Serratia marcescens infection. Evidence of a single source of contamination. Am J Dis Child 135:413-414.
13. Halle E, Grauel EL, Klare I (1989) Nosocomial infections by multiresistant Serratia marcescens in a university clinic Aspects of the clinic and chemotherapeutic resistance. Padiatr Grenzgeb 28: 299-309.
14. Villari P, Crispino M, Salvadori A, Scarcella A (2001) Molecular epidemiology of an outbreak of Serratia marcescens in a neonatal intensive care unit. Infect Control Hosp Epidemiol 22: 630-634.