Among the extra pulmonary forms of tuberculosis (TB), the osteoarticular localization has been detached in 1–2% of cases. In 30% of these children either a pulmonary and extra-pulmonary localization was found. The diagnosis of skeletal TB is often insidious due to variable signs and symptoms.

The medical records of children admitted to our center between 2006 and 2013 due to skeletal TB were evaluated. All patient underwent TB skin test, IGRA test, chest X-ray and focused imaging tests. In the complicated forms of osteoarthritis the infected material drained spontaneously or surgically was analyzed for Mycobacterium Tuberculosis (MT) detection and culture. In patients with pulmonary localization gastric aspirates or sputum analysis was performed.

Nine patients met the inclusion criteria. The median age at diagnosis was 7 (range 2–13) years. All patients presented with local osteoarticular symptoms and 4 of them had fever. In five cases there was a preceding history of minor trauma. Three patients had a case of TB in the family. Four patients had a spinal localization, three hips and two ankles. ERS and CRP values were altered in 7 and 4 patients respectively. All patient underwent radiography, bone three phase scintigraphy and a MRI. The diagnosis of tuberculosis was confirmed by histopathological examination of bone biopsy in 6 (66%) cases. The skin test and the IGRA test were positive in all patients. The chest X-ray showed a pulmonary localization in 3 cases that had positive gastric aspirate or sputum. All patients were treated with isoniazid, rifampicin pyrazinamide and ethambutol. In 3 patients Linezolid or Ciprofloxacin was also associated. The follow-up had an average value of 34 months. Sequelae were reported in 7 patients (limping in 5 cases, severe kyphosis in 2 cases).

Owing to its low incidence in developed countries, the diagnosis ot TB is often delayed for months to years. Additionally, we highly recommend taking a biopsy of the site of suspected infection because an early diagnosis is the key to successful treatment.

Daptomycin is a novel lipopetide antibiotic against gram-positive organisms, including multi-resistant strains. It effectively penetrates bone and has bactericidal activity within biofilms. In adults it has been demonstrated active against Staphylococcus Aureus Methicillin Sensible (MSSA) and Resistant (MRSA) bacteremia. The main side effect is a transitory myopathy that appears to be dose and frequency related. There are limited dates on daptomycin in pediatric patients.

We reviewed the medical records of four children (3 males and 1 female), with a median age of 11.2 years (range 7–13 years), who received daptomycin therapy for a complicated osteomyelitis. Osteomyelitis was clinically suspected and confirmed by magnetic resonance imaging at left ankle, left tibia, left calcaneum, lumbar column.

The pathogen isolated was a MSSA in all four cases. All patients received prior antibiotic treatment. Therapy was swiched to Daptomycin for first line treatment failure (in three cases) and for an adverse reaction to first line treatment (in one case). Daptomycin was prescribed at the mean dosage of 9 mg/kg/day (range 8–10 mg/kg/day) for a median time of 15 days. After 4 days therapy, all patients clinically and laboratory improved with resolution of fever and pain and decreased inflammatory indexes. No patient underwent surgery. After a median of 20 days of hospitalization, patients were discharged with oral antibiotic therapy. They received follow-up clinical evaluation for 8 months (range 6–10 months) with no sequelae.

With the limits of a small population and of a retrospective and unblended study, daptomycin therapy may be useful in complicated osteomyelitis and allowed the avoidance of surgery. The good outcome of the patients was probably due to daptomycin bactericidal activity against bacteria and to its ability to penetrate into bone and synovial fluid. Daptomycin therapy has been well tolerated in all patients, even if administered at a higher dose. No side effect was reported during therapy and at a 30 days follow-up evaluation.