Protean infectious types and frequent association with neurosurgical procedures in adult Serratia marcescens CNS infections: report of two cases and review of the literature

A preliminary exploration on the mechanism of the carbapenem-resistance transformation of Serratia marcescens in vivo

BACKGROUND

The infection of carbapenem-resistant organisms was a huge threat to human health due to their global spread. Dealing with a carbapenem-resistant Serratia marcescens (CRSM) infection poses a significant challenge in clinical settings. This study aims to provide insights into strategies for controlling CRSM infection by exploring the transformation mechanism of carbapenem-resistance.

METHODS

We used whole genome sequencing (WGS) to investigate the mechanism of carbapenem resistance in 14 S. marcescens isolates in vivo. The expression level of related genes and the minimum inhibitory concentration of meropenem (MICMEM) were also evaluated to confirm the mechanism of carbapenem resistance.

RESULTS

Seven groups of S. marcescens, each consisting of two strains, were collected from a hospital and displayed a shift in MICMEM from low to high levels. Homology analysis revealed that the isolates in five groups were significantly different from the remaining two. WGS and experimental evidence indicated that four groups of strains developed carbapenem resistance by acquiring the blaKPC (obtaining group), while two groups (persisting group) increased the expression level of the blaKPC. In contrast, isolates in the last group (missing group) did not carry the blaKPC. All strains possessed multiple β-lactamase genes, including blaCTX-M-14, blaSRT-1, and blaSRT-2. However, only in the missing group, the carbapenem-resistant strain lost an outer membrane protein-encoding gene, leading to increased blaCTX-M-14 expression compared to the carbapenem-susceptible strain.

CONCLUSION

The study findings suggest that S. marcescens strains developed diverse carbapenem resistance in vivo through the evolution of drug resistance, rather than through clone replacement. We hypothesize that carbapenem resistance in S. marcescens was due to certain clonal types with a distinct mechanism.

Epidural Abscess Following Epidural Evacuation in a Patient With Ventriculoperitoneal Shunt: A Case Report

Epidural abscess is considered one of the most common intracranial infections. We report a pediatric patient with chronic hematopoiesis and thick double periosteal layers who developed an epidural pus collection after epidural hematoma evacuation. This article highlights the importance of detecting complications from epidural hematoma evacuation, including intracranial abscess and pus formation. Therefore, it is crucial to treat such cases meticulously.

Serratia Liver Abscess Infection and Cardiomyopathy in a Patient with Diabetes Mellitus: A Case Report and Review of the Literature

Patient: Female, 45

Final Diagnosis: Serrata liver abscess with diabetes mellitus and cardiomyopathy

Symptoms: Anxiety • generalized weakness

Medication: —

Clinical Procedure: —

Specialty: General and Internal Medicine

An unusual cause of ventriculoperitoneal shunt infection

Infection associated with ventriculoperitoneal (VP) shunt implantation can be a significant problem. VP shunt infection with Serratia marcescens, a gram-negative anaerobic rod, usually is related to underlying abdominal disease. This article describes treatment of two patients suffering from a VP shunt infection with S. marcescens without underlying abdominal disease.

Serratia marcescens meningitis: epidemiology, prognostic factors and treatment outcomes

BACKGROUND/PURPOSE

Serratia marcescens is a rare pathogen of central nervous system infections. This study was to investigate the epidemiology, prognostic factors, and treatment outcomes of S. marcescens meningitis.

METHODS

This retrospective analysis included 33 patients with culture-proven S. marcescens meningitis hospitalized between January 2000 and June 2011.

RESULTS

Of the 33 patients enrolled, only one did not receive neurosurgery before the onset of S. marcescens meningitis. Patients with S. marcescens meningitis had higher ratios of brain solid tumors (54.5%) and neurosurgery (97.0%) with a mortality rate of 15.2%. The mean interval between the first neurosurgical procedure and the diagnosis of meningitis was 17.1 days (range, 4-51 days). Only one third-generation cephalosporin-resistant S. marcescens isolate was recovered from the patients' cerebrospinal fluid (CSF) specimens. Compared with the favorable outcome group (n = 20), the unfavorable outcome group (n = 13) had a higher percentage of brain solid tumors, more intensive care unit stays, and higher Sequential Organ Failure Assessment score, CSF lactate and serum C-reactive protein concentrations at diagnosis of meningitis. Under the multiple regression analysis, CSF lactate concentration ≥2-fold the upper limit of normal (ULN) was independently associated with unfavorable outcomes (odds ratio, 7.20; 95% confidence interval, 1.08-47.96; p = 0.041).

CONCLUSION

S. marcescens meningitis is highly associated with neurosurgical procedures for brain solid tumors. CSF lactate concentration ≥2x ULN may predict an unfavorable outcome. Its mortality is not high and empiric treatment with parenteral third-generation cephalosporins may have a satisfactory clinical response.

Community-acquired Serratia marcescens spinal epidural abscess in a patient without risk factors: Case report and review

Serratia marcescens has rarely been reported as an agent of invasive disease in patients presenting from the community. Furthermore, S marcescens is frequently opportunistic, affecting individuals with serious medical comorbidities including immune suppression and diabetes. A case of a community-acquired S marcescens spontaneous lumbar epidural abscess presenting as cauda equina syndrome is reported in a previously well 36-year-old man with no identifiable risk factors. To the authors' knowledge, this is the first report of invasive S marcescens causing disease in a patient with no medical comorbidities.

Treatment of Serratia marcescens meningitis with prolonged infusion of meropenem

OBJECTIVE

To describe the use of and cerebral spinal fluid (CSF) penetration of a prolonged infusion meropenem regimen in a patient with Serratia marcescens meningitis.

CASE SUMMARY

A 54-year-old female was diagnosed with S. marcescens meningitis associated with an epidural abscess 57 days after surgery for a herniated spinal disk. Meropenem 2000 mg every 8 hours was administered as a prolonged (3 h) infusion for the purpose of optimizing pharmacodynamic exposure. Meropenem concentrations were measured from the patient's blood and CSF (via a lumbar drain). The prolonged infusion regimen resulted in concentrations in both serum and CSF above the meropenem minimum inhibitory concentration (MIC) of 0.047 microg/mL for 100% of the dosing interval. After 6 days of therapy, the patient showed no further signs of infection and was subsequently discharged to a rehabilitation facility. At follow-up, she had completed a 4 week course of the prolonged infused therapy without relapse or adverse events.

DISCUSSION

Gram-negative infections of the central nervous system result in high morbidity and mortality. These infections are often difficult to treat because of poor antibiotic penetration coupled with increasing antibiotic resistance. Although there are 2 other case reports that describe the use of prolonged infusion of meropenem, our patient had a lumbar drain in place, thereby allowing us to collect multiple CSF samples and more accurately assess meropenem exposure at the site of infection. CSF penetration was 6.4% in this patient, resulting in 100% time above the MIC throughout the dosing interval.

CONCLUSIONS

In this patient with meropenem-susceptible S. marcescens meningitis, the use of a high-dose prolonged infusion of meropenem resulted in adequate exposure at the site of infection and a successful clinical response.

Spontaneous bacterial peritonitis causing Serratia marcescens and Proteus mirabilis ventriculoperitoneal shunt infection. Case report

The authors report their experience treating a polymicrobial ventriculoperitoneal (VP) shunt infection in a developmentally delayed 21-year-old woman. Cerebrospinal fluid (CSF) cultures grew Serratia marcescens and Proteus mirabilis. On admission and throughout her hospitalization, results of physical examination of her abdomen were normal, and radiographic studies showed no evidence of bowel perforation or pseudocyst formation. Contrast-enhanced computed tomography of the abdomen revealed a small fluid collection. After a course of intravenous gentamicin and imipenem with cilastatin in conjunction with intrathecal gentamicin, the infection was resolved and the VP shunt was reimplanted. Although VP shunt infections are not uncommon, S. marcescens as a causative agent is exceedingly rare and potentially devastating. Only two previous cases of S. marcescens shunt infection have been reported in the literature. Authors reporting on S. marcescens infections in the central nervous system (CNS) have observed significant morbidity and death. Although more common, the presence of P. mirabilis in the CSF is still rare and highly suggestive of bowel perforation, which was absent in this patient. Spontaneous bacterial peritonitis was the likely source from which these bacteria gained entrance into the VP shunt system, eventually causing ventriculitis in this patient. The authors conclude that in light of the high morbidity associated with S. marcescens infection of the CNS, intrathecal administration of gentamicin should be strongly considered as part of first-line therapy for S. marcescens infections in VP shunts.

Ventriculoperitoneal shunt infection due to Serratia marcescens

Serratia marcescens is an opportunistic Gram-negative bacillus that is most often associated with infections of the respiratory tract, urinary tract, wounds, and bloodstream. Infections of the central nervous system (CNS) with this pathogen are exceedingly infrequent. Even more rare is the association of S. marcescens with infections of ventriculoperitoneal (VP) shunts. To the best of our knowledge, we describe in this report not only the first case of a VP shunt infection by S. marcescens in an adult, but also the first case of a VP shunt infection by this organism in the absence of bowel perforation.