A 26-month-old girl underwent surgery for a grade II right frontoparietal ependymoma, in which the tumor was completely resected. Dexamethasone (1 mg/kg/day) was given 8 days after surgery as antiedema treatment. Seven days after the operation, the child suffered an episode of vomiting and diarrhea that lasted 24 hours. Two days later, she presented at the Emergency unit with a fever of 39°C. Her general state was good, with no neurological signs or other accompanying symptoms. Of the blood tests performed on hospital admission, the following results are of interest: 12000 leucocytes per mm3, with 72% neutrophils and 8 mg/dl and C-reactive protein (CRP) (normal < 0.5 mg/dl). On suspicion of a possible complication of surgery, a cranial CT-scan was requested, which showed a fluid collection indicative of a right epidural parietal empyema (Figure 1A). Through a right parietal craniectomy, the epidural fluid collection was drained and a sample obtained for culture. After placement of a subdural drainage tube the patient was started on empirical antibiotic treatment with ceftazidime and vancomycin.
Cultures of the epidural empyema fluid, cerebrospinal fluid and feces revealed the growth of Salmonella enterica, subspecies enterica I, serotype Enteritidis 9, 12: g, m, phage type 6a.
In all the cultures, MICs for ceftazidime (1 ≤ μg/mL), cefotaxime (1 ≤ μg/mL), ciprofloxacin (1 ≤ μg/mL), nalidixic acid (4 ≤ μg/mL), and chloramphenicol (8 ≤ μg/mL) indicated a good sensitivity of the bacterium to these antibiotics.
On the sixth day of empirical antibiotic treatment, the patient continued to have fever and clonic jerking started in the left arm. A further CT scan revealed a right frontoparietal lesion with rim enhancement consistent with a cerebral abscess (Figure 1B).
A drainage tube was placed in the abscess (Figure 1C), and anticonvulsant therapy with valproic acid initiated. At this time point, vancomycin was discontinued and ceftazidime was replaced with i.v. chloramphenicol and this new antibiotic regimen continued for 4 weeks. In the fluid evacuated from the abscess, an identical strain of Salmonella enteritidis as in the previous cultures was identified. Twenty four hours after the introduction of chloramphenicol and placement of the new drainage tube, the infant's temperature returned to normal and she suffered no more seizures. Given that Salmonella enteritidis continued to appear in cultures of the abscess drainage fluid, on day 38 of treatment, chloramphenicol was replaced with i.v. ciprofloxacin and i.v. cefotaxime. This regimen was maintained for 2 weeks. The patient was discharged after 7 weeks of intravenous antibiotic treatment and was given oral ciprofloxacin at home for a further 15 days.
Lesion progression was monitored weekly by transcraniectomy cerebral ultrasonography and monthly by cerebral NMR. These follow up exams revealed a gradual reduction in abscess size until its resolution 9 weeks after the onset of antibiotic therapy.
At 10 months, the previously extracted and sterilized bone fragment was replaced by cranioplasty. After two years of follow up, the child is well with no signs of infection or tumor recurrence observed in the CT or NMR scans. She has no neurological or development alterations and her weight and height are within the 50th percentile for her age.