CLINICAL RESEARCH

 

Pyogenic Spinal Infections Without Disc Involvement in Childhood

 

María Emilia Moreiro Varela,*,** María Gabriela Miranda,*,** María Arnelix López Friera,** Claudio A. Fernández*

*School of Medical Sciences, Universidad Nacional de La Plata, Buenos Aires, Argentina

**Orthopedics and Traumatology Service, Hospital de Niños “Sor María Ludovica”, La Plata, Buenos Aires, Argentina

 

ABSTRACT

Introduction: Pyogenic spinal infections in children include spondylodiscitis, spondylitis, facet joint septic arthritis, paraspinal and perivertebral abscesses, meningitis, myelitis, and their associations. Staphylococcus aureus is the most common causative microorganism. Objective: To determine the prevalence of spinal bone infections and pyogenic perivertebral abscesses in children and to evaluate the usefulness of Ju’s algorithm. Materials and Methods: Nine children without comorbidities presenting with pyogenic spinal infection and preserved disc integrity were included. Results: A higher frequency was observed in children older than eight years. The most prevalent clinical triad was pain, fever, and antalgic postures. Ju’s algorithm proved to be reliable. One case of facet joint septic arthritis, four cases of spondylitis, and eight perivertebral abscesses were identified, five associated with bone infection. On CT, bone lesions showed a lytic or mottled appearance, while MRI demonstrated typical infectious patterns. Bone specimens obtained by percutaneous and transoral biopsy confirmed acute osteomyelitis. S. aureus was isolated in seven of nine patients. Antibiotic therapy was effective; however, six children required surgery: five for abscess drainage and one for a pedicle subtraction osteotomy due to residual kyphosis. Conclusions: Spinal infection with preserved disc integrity was prevalent in late childhood and adolescence. Its association with abscess formation and S. aureus infection was significant. We recommend the application of Ju’s algorithm and, in cases of negative blood cultures, performing bone biopsy for bacteriological identification and histopathological confirmation, surgical drainage of soft tissue abscesses, and targeted antibiotic therapy.

Keywords: Children; spinal infection; pyogenic abscesses; Staphylococcus aureus.

Level of Evidence: IV

 

Infecciones espinales piógenas sin afectación discal en la infancia

 

RESUMEN

Introducción: Las infecciones espinales piógenas en la infancia incluyen entidades, como espondilodiscitis, espondilitis, infección facetaria, abscesos para y perivertebrales, meningitis, mielitis y sus asociaciones. Staphylococcus aureus es el microorganismo habitual. Objetivos: Determinar la prevalencia de infecciones óseas espinales y abscesos piógenos perirraquídeos, y evaluar la utilidad del algoritmo de Ju. Materiales y Métodos: Se incluyó a 9 niños con infección espinal piógena e indemnidad discal, sin comorbilidades. Resultados: La frecuencia fue mayor en niños >8 años. La tríada prevalente incluyó dolor, fiebre y posturas antiálgicas. Se demostró que el algoritmo de Ju es confiable. Se detectaron una artritis facetaria, 4 espondilitis y 8 abscesos perivertebrales, 5 asociados a una infección ósea. En la tomografía computarizada, las lesiones óseas tenían un aspecto lítico o atigrado. La resonancia magnética mostró el patrón típico de infección. Los especímenes óseos, obtenidos por punción percutánea y transoral, fueron informados como osteomielitis aguda. En 7 de 9 pacientes, se aisló S. aureus. La antibioticoterapia fue eficaz para curar la enfermedad. Sin embargo, 6 niños requirieron cirugía: 5 para drenar abscesos y uno para una osteotomía de sustracción pedicular en una cifosis secuelar. Conclusiones: La infección vertebral con disco indemne fue prevalente en la segunda infancia y la adolescencia. La asociación con abscesos fue significativa, así como la identificación de S. aureus. Recomendamos la aplicación del algoritmo de Ju y, ante hemocultivos negativos, la biopsia ósea para la determinación bacteriológica y la certeza histopatológica, el drenaje quirúrgico de los abscesos de partes blandas y la antibioticoterapia específica.

Palabras clave: Niños; infección espinal; abscesos piógenos; Staphylococcus aureus.

Nivel de Evidencia: IV

 

INTRODUCTION

Pyogenic spinal infections in childhood are uncommon. Spondylodiscitis predominates; however, other entities may occur, including spondylitis, facet joint infection, meningitis, myelitis, abscesses concomitant with bone infection, and primary perivertebral septic collections.1 Regardless of the presentation, the inoculum enters via the hematogenous route (Figure 1).2

 

 

 

 

 

In recent decades, the epidemic of methicillin-resistant Staphylococcus aureus (MRSA) has substantially altered the spectrum, prevalence, and prognosis of skeletal infections.3,4 The Pan American Health Organization has reported alternative etiologies according to age stratification (Table 1).5

In prior studies, spinal osteomyelitis accounts for 1% to 2% of all bone infections.6

The objectives of this study were to determine the prevalence of spondylitis and pyogenic paraspinal abscesses in children and to assess the usefulness of Ju’s algorithm.

 

 

 

 

 

 

MATERIALS AND METHODS

A descriptive, retrospective observational case series was conducted at a multidisciplinary pediatric referral institution in the Province of Buenos Aires, covering the period from October 2004 to December 2023.

Inclusion criteria were: children up to 15 years of age with a primary pyogenic infection of the spine, without disc involvement or comorbidities, who met two or more of the following requirements: 1) Clinical presentation: spinal pain, refusal to walk or limping, limited range of motion, abnormal postures, and febrile syndrome. 2) Biological pattern of infection: decreased hematocrit or hemoglobin concentration; increased Creactive protein (CRP) or erythrocyte sedimentation rate (ESR). 3) Bacteriological confirmation: identification of the organism on blood culture or aspiration specimen; histopathological confirmation; or any combination of these variables. 4) Imaging findings suggestive of infection. Exclusion criteria were: children with systemic disease, surgical site infection, tuberculosis, and incomplete medical records. We applied the predictive algorithm for S. aureus osteomyelitis described by Ju et al., which includes the following factors: leukocytosis >12,000 cells/mm³, hematocrit <34%, temperature >38°C, and CRP ≥13 mg/L, with the following expected probability of diagnosis: no factors = 0%, one = 1%, two = 10%, three = 45%, and four = 92%.4

In addition to demographic data, we recorded time to presentation/evolution and follow-up, infection location, biological and histopathological parameters, imaging studies, and antibiotic therapy. The classification of bone infection as acute or chronic was based on histopathological confirmation, not on duration of symptoms.

 

Statistical Analysis

The nonparametric Wilcoxon rank test and Pearson’s correlation coefficient were used (SPSS 17®). A p value ≤0.05 was considered statistically significant.

 

RESULTS

Eleven medical records met the aforementioned criteria. Two were excluded due to the lack of imaging documentation. The sample represented 81% of the cases admitted during the study period. The cohort included nine patients with a mean age of 9.6 years (range, 3 months–15 years), with a male-to-female ratio of 6:3. The mean prodromal period was 6 days (range, 48 hours–5 months). Mean follow-up for bone infections was 1.8 years (range, 12–36 months), whereas for primary abscesses without skeletal involvement, the mean follow-up was 9 months (range, 6–18 months).

The predominant clinical presentation included pain, febrile syndrome, limited range of motion, and antalgic postures. No patient developed neurological deterioration. Blood cultures were negative except in two cases, and all patients had a Ju index of 92%, except for one patient (p < 0.002) (Table 2).

 

 

 

 

 

Eight abscesses were identified in nine patients (p = 0.005): three were associated with spondylitis and one with facet joint arthritis; the remaining four were primary abscesses (Figure 2).

 

 

 

 

 

Abscesses associated with spondylitis resolved with antibiotic treatment, whereas the remaining abscesses required surgical drainage, including those in two children whose diagnosis in the emergency department was made exclusively by ultrasound. Staphylococcus aureus was isolated in seven patients (p = 0.001), including four cases of MRSA and three of MSSA (Figures 3-6).

 

 

 

 

 

 

 

 

 

 

 

 

On computed tomography, bone lesions exhibited a lytic or mottled appearance, with asymmetric distribution and poorly defined margins. One patient developed angular kyphosis due to wedging of T11, which required delayed pedicle subtraction osteotomy (Figure 7).

 

 

 

 

 

Magnetic resonance imaging showed hypointense signal on T1-weighted sequences and hyperintense signal on T2-weighted and STIR sequences, with gadolinium enhancement. In patients with bone involvement and negative blood cultures, image-guided needle biopsies were performed: three percutaneous transpedicular biopsies, one transfacet biopsy, and one transoral biopsy. In two cases, no pathogen was identified; in two cases, S. aureus was isolated (1 MRSA and 2 MSSA). All specimens submitted for histopathological analysis were classified as acute osteomyelitis (Figures 8 and 9). According to protocol, all specimens were evaluated for tuberculosis (Figure 10).

 

 

 

 

 

 

 

 

 

 

Antibiotic therapy was guided by antibiogram results or administered empirically, according to local epidemiology. In general terms, the protocol included 2 to 3 weeks of intravenous antibiotics followed by 4 to 8 weeks of oral therapy. The most frequently administered antibiotics were clindamycin and vancomycin. Table 3 summarizes the most relevant variables. Overall, the cohort can be summarized into three main findings: (1) spondylitis, (2) facet joint arthritis, and (3) primary paraspinal abscesses or abscesses associated with the aforementioned bone infections.

 

 

 

 

 

 

DISCUSSION

The vascular pattern appears to be the key differentiating factor in the pathogenesis of vertebral infection in children. In the first years of life, the metaphyseal vascular network facilitates bacterial inoculation, bone abscess formation, and disc involvement.6 From the second stage of childhood onward, spinal blood supply, more prominent at the equator of the vertebral body, predisposes to osteomyelitis that spares the intervertebral disc.2,7,8 Between the ages of 3 and 8 years, the prevalence of spondylodiscitis and spondylitis is similar, after which spondylitis becomes predominant. Reports on pyogenic spondylitis and facet joint arthritis in childhood are scarce.6,8,9 In this study, five cases were identified over a 19-year period. The deleterious effect of Staphylococcus aureus is manifested by tissue necrosis, abscess formation, and recurrence.10-14 The production of exotoxins, such as Panton–Valentine leukocidin, α-hemolysin, enterotoxins, and superantigens, may trigger a generalized inflammatory storm, leading to hemodynamic shock, multiple organ failure, and death.11,12 According to the literature, deep abscesses, cellulitis, and furunculosis are caused by MRSA in 63% of cases and by MSSA in 15%.14,15 In this cohort, the incidence of paraspinal abscesses was close to 90%, caused by both bacterial species (Table 3).

Drainage and saline irrigation of posterior septic collections appears to be a generally accepted procedure.14 However, there are no standardized indications regarding anterior collections. In principle, provided that there is no alteration of spinal biomechanics, instability, or neurological compromise, initial management consists of antibiotic therapy.

Diagnostic confirmation by histopathology, bacteriology, or both methods allowed us to corroborate, albeit inversely, the usefulness of the algorithm proposed by Ju et al.4 Other authors have reported disparate results, with a reliability of 91% at Boston Children’s Hospital and 50% at Phoenix Children’s Hospital.4,11,15 Computed tomography has moderate sensitivity in infectious disease; it is useful for bone tissue analysis and 3D reconstructions. However, long-term carcinogenic effects related to radiation exposure in children have been reported.16 Therefore, its indication should be selective, and whenever possible, biopsies should be performed using image-intensifier–assisted needle techniques with limited imaging sequences. Magnetic resonance imaging is the imaging modality of choice in patients with spinal infection, with a sensitivity of 96%, specificity of 94%, and accuracy of 92%.1 Occasionally, on T2-weighted sequences, a “flare phenomenon” may be observed, which has also been described in stress fractures and neoplastic disease.17 Granulomatous tissue formation may mimic a paraspinal abscess in hematological malignancies. The association of spondylitis and abscess should be considered tuberculosis until proven otherwise.18-21 For this reason, we developed a comparative table with pyogenic infections based on the literature (Table 4).19-21

 

 

 

 

 

Unlike spondylodiscitis, in which the indication for needle aspiration remains controversial, we believe that in patients with bone lesions and negative blood cultures, biopsy is essential because of its bacteriological relevance and histopathological diagnostic certainty, particularly in view of the broad differential diagnosis.

The main limitations of this study are its retrospective design and the size of the cohort; however, the latter is relative, as this analysis addresses rare forms of spinal infection in children.

 

CONCLUSIONS

Pyogenic vertebral osteomyelitis without disc involvement is common in late childhood and adolescence, as is the concomitant presence of paraspinal abscesses and the etiological predominance of S. aureus. We recommend the application of Ju’s algorithm and, in cases of negative blood cultures, bone biopsy for bacteriological and histopathological diagnosis, surgical drainage of soft tissue abscesses, and targeted antibiotic therapy.

With inferential statistics, the variables were analyzed using the Wilcoxon nonparametric rank test and the Pearson correlation coefficient. For bone infection and abscesses, all variables were statistically significant when compared with the final definitive diagnosis (bacteriological or histological), p < 0.002.

 

REFERENCES

 

1.     Arbelaez A, Restrepo F, Castillo M. Spinal infections: clinical and imaging features. Top Magn Reson Imaging 2014;23(5):303-14. https://doi.org/10.1097/RMR.0000000000000032

2.     Wiley AM, Trueta J. The vascular anatomy of the spine and its relationship to pyogenic vertebral osteomyelitis. J Bone Joint Surg Br 1959;41:796-809. https://doi.org/10.1302/0301-620X.41B4.796

3.     Miranda MG. Patología infecciosa infantil. In: Romano O, Fernández C. Lo esencial en Ortopedia y Traumatología. La Plata: EDULP; 2023, p. 460-478.

4.     Ju KL, Zurakowski D, Kocher MS. Differentiating between methicillin-resistant and methicillin-sensitive Staphylococcus aureus osteomyelitis in children: an evidence-based clinical prediction algorithm. J Bone Joint Surg Am 2011;93(18):1693-701. https://doi.org/10.2106/JBJS.J.01154

5.     Organización Panamericana de la Salud. Tratamiento de las enfermedades infecciosas 2020-2022, 8ª ed. Washington, DC: OPS; 2019, p. 70-3.

6.     Fernandez M, Carrol CL, Baker CJ. Discitis and vertebral osteomyelitis in children: an 18-year review. Pediatrics 2000;105(6):1299-304. https://doi.org/10.1542/peds.105.6.1299

7.     Fernández CA. Espondilodiscitis. In: Romano O, Fernández C. Lo esencial en Ortopedia y Traumatología. La Plata: EDULP; 2023, p. 749-65.

8.     Ceroni D, Chargui M, De Marco G, Steiger C, Dayer R. Better Comprehension of primary pyogenic spinal infections. Pediatr Infect Dis J 2023;42(1):e39-e40. https://doi.org/10.1097/INF.0000000000003745

9.     Mas-Atance J, Gil-García MI, Jover-Sáenz A, Curià-Jové E, Jové-Talavera R, Charlez-Marco A, et al. Septic arthritis of a posterior lumbar facet joint in an infant: a case report. Spine (Phila Pa 1976) 2009;34(13):E465-8. https://doi.org/10.1097/BRS.0b013e3181a4e64b

10.  Bouali N, Haddaji N, Hamadou WS, Ghorbel M, Bechambi O, Mahdhi A, et al. Methicillin-resistant Staphylococcus aurous: Epidemiology, transmission and new alternative therapies: A narrative review. Iran J Public Health 2023;52(8):1555-64. https://doi.org/10.18502/ijph.v52i8.13395

11.  Pendleton A, Kocher MS. Methicillin-resistant staphylococcus aureus bone and joint infections in children. J Am Acad Orthop Surg 2015;23(1):29-37. https://doi.org/10.5435/JAAOS-23-01-29

12.  Hawkshead JJ 3rd, Patel NB, Steele RW, Heinrich SD. Comparative severity of pediatric osteomyelitis attributable to methicillin-resistant versus methicillin-sensitive Staphylococcus aureus. J Pediatr Orthop 2009;29(1):85-90. https://doi.org/10.1097/BPO.0b013e3181901c3a

13.  Díaz Gallardo P, Mangupli M, Galera H, Bruno P, Bustos D, Ferrer G, et al. Staphylococcus aureus sensible a la meticilina frente a Staphylococcus aureus resistente en la artritis séptica aguda: estudio experimental, epidemiológico y clínico en niños. Rev Asoc Argent Ortop Traumatol 2011;76(2):112-21. Available at: https://www.scielo.org.ar/scielo.php?pid=s1852-74342011000200003&script=sci_arttext

14.  Fujita Y, Matsudera S, Watanabe S, Yamaguchi T, Suzuki K, Ohkusu M, et al. Extensive subcutaneous abscess due to Panton-Valentine leucocidin-positive community-associated methicillin-resistant Staphylococcus aureus in an infant. Tohoku J Exp Med 2022;258(4):303-7. https://doi.org/10.1620/tjem.2022.J086

15.  Wade Shrader M, Nowlin M, Segal LS. Independent analysis of a clinical predictive algorithm to identify methicillin-resistant Staphylococcus aureus osteomyelitis in children. J Pediatr Orthop 2013;33(7):759-62. https://doi.org/10.1097/BPO.0b013e3182a11cf7

16.  Brenner D, Elliston. C, Hall E, Berdon W. Estimated risks of radiation-induced fatal cancer from pediatric CT. AJR Am J Roentgenol 2001;176(2):289-96. https://doi.org/10.2214/ajr.176.2.1760289

17.  Azouz EM. Magnetic resonance imaging of benign bone lesions: cysts and tumors. Top Magn Reson Imaging 2002;13(4):219-29. https://doi.org/10.1097/00002142-200208000-00003

18.  Fernández CA, Miranda MG, Fiore NJ. Tumores espinales primarios en la infancia: epidemiología, diagnóstico, estadificación y tratamiento. Rev Asoc Argent Ortop Traumatol 2010;75(1):13-26. Available at: https://www.scielo.org.ar/scielo.php?pid=S1852-74342010000100003&script=sci_arttext&tlng=pt

19.  Lee, KY. Comparison of pyogenic spondylitis and tuberculous spondylitis. Asian Spine J 2014;8(2):216-23. https://doi.org/10.4184/asj.2014.8.2.216

20.  Jain AK. Tuberculosis of the spine: a fresh look at an old disease. J Bone Joint Surg Br 2010;92(7):905-13. https://doi.org/10.1302/0301-620X.92B7.24668

21.  Manzone P, Quiroz LJ, Vallejos Arce MS, Mariño Ávalos E, Laluf AF, et al. Mal de Pott en la provincia del Chaco. Rev Asoc Argent Ortop Traumatol 2017;82(3):206-19. Available at: https://www.scielo.org.ar/scielo.php?pid=S1852-74342017000300007&script=sci_arttext

 

 

M. E. Moreiro Varela ORCID ID: https://orcid.org/0009-0000-5590-9738

M. A. López Friera ORCID ID: https://orcid.org/0009.0006-3788-2133

M. G. Miranda ORCID ID: https://orcid.org/0000-0003-4949-9407

 

Received on July 19th, 2024. Accepted after evaluation on June 23rd, 2025 • Dr. Claudio A. Fernández • claudioalfredofernandez619@gmail.com • https://orcid.org/0000-0003-2350-3885

 

How to cite this article: Moreiro Varela MI, Mirando MG, López Friera MA, Fernández CA. Pyogenic Spinal Infections Without Disc Involvement in Childhood. Rev Asoc Argent Ortop Traumatol 2026;91(1):7-17. https://doi.org/10.15417/issn.1852-7434.2026.91.1.2000

 

 

Article Info

Identification: https://doi.org/10.15417/issn.1852-7434.2026.91.1.2000

Published: February, 2026

Conflict of interests: The authors declare no conflicts of interest.

Copyright: © 2026, Revista de la Asociación Argentina de Ortopedia y Traumatología.

License: This article is under Attribution-NonCommertial-ShareAlike 4.0 International Creative Commons License (CC-BY-NC-SA 4.0).