ArticlePlus Click on the links below to access all the ArticlePlus for this article. Please note that ArticlePlus files may launch a viewer application outside of your web browser. https://links.lww.com/INF/A67 To the Editors: In this letter we describe a patient with Grisel syndrome after an unusual anaerobic infection. A 2-year-old boy was admitted to the hospital with meningitis. Laboratory tests showed elevated inflammatory markers (leukocyte count, 12.3 × 10 E 9/L; neutrophils, 8.1 × 10 E 9/L; C-reactive protein, 423 mg/L). Analysis of cerebrospinal fluid (CSF) showed neutrophilic pleocytosis, reduced glucose concentration, and normal protein. The stained smear of CSF showed Gram-negative bacilli, but the aerobic culture remained sterile. A susceptible Bacteroides ureolyticus was isolated from the anaerobic blood culture. Magnetic resonance imaging (MRI) of head and spine showed signs of a retropharyngeal infiltrate with reactive inflammation or edema of the clivus. Puncture of the process showed no pus. Initial treatment consisted of ceftriaxone 100 mg/kg and metronidazole 30 mg/kg. Because of persisting fever antibiotic therapy was changed to meropenem (120 mg/kg), after with the patient recovered within 4 days. Four weeks after initial presentation he became subfebrile and was unable to move his neck. His head remained fixed in neutral position. There were no neurologic abnormalities. Laboratory test showed an erythrocyte sedimentation rate of 85 mm/h and C-reactive protein of 16 mg/L. Conventional radiography of the cervical spine showed enlargement of the distance between the dens and the atlas. MRI showed a fluid collection just frontal to the clivus with signs of inflammation and signs of C1–C2 subluxation. Grisel syndrome resulting from a retropharyngeal abscess or osteomyelitis of C2 was suspected. Subsequent therapy consisted of intravenous meropenem for 4 weeks, followed by oral clindamycin 25 mg/kg for 14 days. The neck was immobilized with a (Minerva) collar for 4 weeks, followed by a soft collar for 4 weeks. No neurologic complications occurred, and our patient recovered completely. Grisel syndrome is a rare condition characterized by nontraumatic atlanto-axial dislocation. Children are believed to be at a higher risk because of the anatomy of the pediatric spine and the higher incidence of infections of the upper respiratory tract.1 Patients classically present with painful torticollis in which rotation of the neck passed the midline to the contra lateral side of the lesion is impossible. The head is held in “cock-robin” position (head tilting in forward position). Swelling of the retropharynx and Sudeck sign (spinous process of the axis palpable in the contralateral neck) can be noted on physical examination. In 15% of cases neurologic complications occur, ranging from radiculopathy to death caused by medullary compression.1 Diagnosis is confirmed by radiograph of the cervical spine, which showed that the distance between C1 and C2 is increased. Confirming the diagnosis is possible with computed tomography or MRI.1,2 Most treatment strategies are based on the Fielding classification system (Table 1; available online only)2,3 and comprise antibiotic treatment, immobilization and traction of the neck, and in case of neurologic complications or failure of treatment, cervical arthrodesis.1 Our patient presented with a meningitis in which the culture of the CSF was sterile, but the stained smear showed Gram-negative bacilli. In our hospital only aerobic culture of CSF is routinely performed. The anaerobic blood culture yielded B. ureolyticus, an anaerobic Gram-negative bacillus. Studies have shown that anaerobes account for 2.1–5.8% of all cases of bacteremia in children.4 Most frequently, anaerobic sepsis is caused by Bacteroides species, in which case B. fragilis is the most common pathogen and B. ureolyticus is uncommon.4–6 To our knowledge there have been no previous reports of meningitis caused by B. ureolyticus. In the case of bacteremia caused by anaerobic organisms, a primary focus of infection (abdominal/urogenital tract/respiratory tract/soft tissue) is almost always present.5 Depending on localization surgical drainage of the primary focus is essential to optimize treatment. Antibiotic treatment covering both anaerobic and aerobic microorganisms is necessary because of the polymicrobial nature of these infections.6 In our patient the retropharyngeal infiltrate demonstrated on MRI seemed the focus for the Bacteroides bacteremia. Jantien W. Wieringa, PhD Tom F. W. Wolfs, MD, PhD Marlies A. van Houten, MD, PhD Department of Pediatrics Spaarne Hospital Hoofddorp, The Netherlands [email protected] Wilhelmina Children’s Hospital University Medical Center Utrecht Department of Pediatrics Division of Infectious Diseases Utrecht, The Netherlands