Paecilomyces/ Purpureocillium Infection in Children, Case Report, and Review of the Literature

Abstract

Paecilomyces/Purpureocillium has recently been recognized as an emerging human pathogen, causing serious infection in immunocompromised and immunocompetent patients. Several predisposing factors have been reported, including foreign body implants, previous surgery, or trauma. Treatment with antifungal drugs often fails as species-specific differences in antifungal susceptibilities are one of the management challenges. Surgical debridement with or without antifungal therapy was sufficient to cure the infection in a few reported cases. Nonetheless, the surgical approach has been found to decrease the chance of dissemination and recurrence. Here, we report the first pediatric patient with chronic osteomyelitis of the femur secondary to Paecilomyces species, with no predisposing risk factors. Our case was successfully treated with a combination of antifungal therapy and surgical debridement. Additionally, we describe the first extensive literature review of previously reported Paecilomyces/Purpureocillium species infections in pediatric age groups.

Keywords: Paecilomyces; Purpureocillium; fungal; immunocompetent; osteomyelitis; pediatric.

Figure 1

(A) Hip X-ray showed increased sclerosis with central lucency at the medial aspect of left femoral neck associated with the cortical irregularity and periosteal reaction; (B) Computed Tomography (CT) scan confirmed the erosive nature of the lesion with adjacent sclerosis and the adjacent bony overgrowth.

Figure 2

Magnetic Resonance Imaging (MRI) of the hip revealed bony overgrowth of the lesser trochanter with early cystic formation and a fluid-fluid level, extensive bone marrow edema, extensive adjacent soft tissue edema and hip joint effusion with evidence of synovial thickening and enhancement post contrast administration.

Figure 3

Histopathological findings in bone tissue (A) There are scattered bone trabeculae and fibroconnective tissue exhibiting dense inflammation and collection of hemosiderin-laden macrophages (lower left); (B) Collection of neutrophils forming micro-abscess.

Figure 4

(A) Pre-surgical X-ray showed worsening of medial femoral erosions and destruction with adjacent sclerosis; (B) Post-surgical X-ray demonstrated interval sclerosis and healing with new bone formation along the medial aspect of femoral neck with interval reduction of erosive changes and medial neck lytic lesion.