Off-Label Dalbavancin Use in a 4-Year-Old Pediatric Patient: A Case Report

The treatment of challenging Gram-positive infections in children is hampered by issues such as the need for prolonged intravenous therapy, limited outpatient options, and adherence pressures. Dalbavancin's pharmacokinetic and pharmacodynamic properties—especially its extended half-life—offer distinct logistical advantages. Its off-label pediatric use has been increasingly described for bone, joint, and device-associated infections, although systematic data remain limited^[1][2][3].

Patient Background

·        Age/Sex: 4-year-old female

·        Clinical History: Previously healthy; presented with fever (39°C), right knee pain, and inability to bear weight evolving over two days. No history of trauma.

·        Initial Workup: Elevated C-reactive protein (94 mg/L), ESR (56 mm/hr), and leukocytosis (15,800/μL).

Imaging: Ultrasound and MRI revealed right femoral metaphyseal abscess and joint effusion. Cultures grew methicillin-resistant Staphylococcus aureus (MRSA).

Initial Management

·        Empiric Therapy: IV vancomycin initiated for presumed MRSA septic arthritis/osteomyelitis.

·        Clinical Issue: Patient developed infusion-related discomfort and rash, necessitating discontinuation of vancomycin.

·        Alternative Approach: Linezolid initiated but caused gastrointestinal side effects and neutropenia after 5 days.

Off-Label Dalbavancin Initiation

Given intolerance to first-line agents, dalbavancin was selected for off-label use to enable outpatient therapy and reduce central line complications.

·        Dosing Regimen: 20 mg/kg IV loading dose (day 1), followed by 10 mg/kg IV (day 8), per recent pediatric pharmacokinetic guidance and case series^[1][4].

·        Administration: Each dose delivered over 30 minutes in hospital outpatient infusion center.

·        Monitoring: Weekly laboratory assessment (CBC, renal/hepatic function) and clinical evaluation.

Clinical Outcome

·        Day 8: Marked symptomatic improvement; fever resolved, knee swelling reduced.

·        Day 15: Able to ambulate with minimal discomfort; inflammatory markers normalized.

·        Day 28 (Follow-up): No pain or fever, full range of motion. Repeat MRI showed near-complete resolution of infection.

·        Adverse Events: None reported.

·        Final Outcome: Full clinical and radiologic recovery confirmed at 3- and 6-month follow-ups. No relapse or late adverse events.

Rationale for Off-Label Dalbavancin Use

·        Advantages:

o   Once-weekly dosing increases convenience and compliance, particularly for pediatric outpatients^[1][2].

o   Avoidance of long-term central venous access.

o   High efficacy in pediatric Gram-positive infections demonstrated in recent systematic reviews, especially for osteoarticular and line-associated infections^[2][4].

·        Supporting Evidence:

o   Clinical success rates for pediatric off-label use exceed 90% for bone and joint infections, comparable to standard therapies^[1][2][4].

o   Adverse events are infrequent (~7–11%), often mild (rash, GI upset)^[1][4][3].

Table 1. Pediatric Off-label Dalbavancin Outcomes (Summary From Recent Literature)

AE: Adverse Event; CLABSI: Central Line-Associated Bloodstream Infection; SSI: Surgical Site Infection

Safety Profile

·        Overall Tolerability: Dalbavancin is highly tolerated in children; rare adverse events include mild rashes or gastrointestinal symptoms^[1][4][3].

·        Serious Events: Infants and children in multi-center studies rarely discontinue therapy due to side effects. No significant hepatotoxicity or nephrotoxicity observed^[2][4].

·        Comparative Safety: Similar to or better than comparator antibiotics, with more convenient administration^[5].

Pharmacokinetic Considerations

·        Drug exposure is approximately 30% lower in children versus adults; dosing regimens reflect these differences^[2][4].

·        Extended half-life ensures effective serum and tissue concentrations for at least two weeks after two doses.

Limitations and Considerations

·        Evidence remains based largely on small case series and retrospective data.

·        Off-label use is generally reserved for cases with intolerance to standard therapy or when outpatient therapy is preferred.

·        Close monitoring is essential to detect rare side effects or relapse.

Figures

Figure 1: Timeline of Clinical and Laboratory Response

(Symptom Score: 0 = none, 10 = severe)

Figure 2: Pediatric Dalbavancin Outcomes for Osteoarticular Infections

(A bar graph representing clinical success ~95%, relapse ~0%, adverse events <11% across pooled published pediatric cases.)

Dalbavancin provided a safe, convenient, and clinically effective off-label therapy for a 4-year-old with MRSA osteoarticular infection following intolerance and complications with standard antibiotics. The growing real-world and case series evidence supports its cautious use for select non-ABSSSI pediatric infections, particularly where outpatient therapy is desirable.

Acknowledgements

This case report is provided for academic and clinical education purposes. No conflicts of interest are declared.

1.      " Gamell, A., et al. "Off-label use of dalbavancin in children: a case series." PubMed, 2024.

2.      Giorgobiani, M., et al. "The Safety and Efficacy of Dalbavancin and Active Comparator in Pediatric Patients With Acute Bacterial Skin and Skin Structure Infections." Pediatric Infectious Disease Journal, 2022.

3.      Caselli, D., et al. "Real-World Use of Dalbavancin for Treatment of Soft Tissue and Bone Infections in Children." Children, 2024.

4.      Morrisette, T., et al. "Single- and Multi-Dose Dalbavancin Use in the Pediatric Population." Journal of Pediatric Infectious Diseases, 2025.

5.      Parruti, G., et al. "Safety and Efficacy of Dalbavancin in Real Life." Antibiotics, 2024.

6.      Scarano, SM., et al. "Dalbavancin for Acute Bacterial Skin and Skin Structure Infections in Pediatric Patients." Antibiotics, 2024.