Francisella philomiragia adenitis and pulmonary nodules in a child with chronic granulomatous disease

Abstract

Francisella philomiragia is a rare and opportunistic pathogen capable of producing invasive infection in patients with compromised neutrophil function and in patients that have survived a near-drowning. A case of F philomiragia adenitis and lung nodules, refractory to cephalosporin therapy, is reported in a 10-year-old boy with chronic granulomatous disease following a facial abrasion from a saltwater crab. To the authors' knowledge, this is the first Canadian clinical isolate to be reported. Genus and species identification was confirmed via 16S ribosomal RNA sequence analysis. A literature review revealed three groups at risk of F philomiragia infection: young patients with chronic granulomatous disease; adults with hematogenous malignancy; and near-drowning patients. Pneumonia, fever without an apparent source and sepsis are the main clinical presentations. Invasive procedures may be required to isolate this organism and ensure appropriate antimicrobial therapy. Limited awareness of F philomiragia has led to delayed identification, patient death and misidentification as Francisella tularensis - a biosafety level three pathogen and potential bioterrorism agent.

Keywords: Chronic granulomatous disease; Francisella philomiragia.

Figure 1

Computed tomography examination of the thorax with intravenous contrast enhancement shows a small triangular airspace opacity in the posterior segment of the right upper lobe (arrow)

Figure 2

Computed tomography image of the right lung demonstrating pulmonary nodules (arrow)

Figure 3

Typical Francisella philomiragia colonies on sheep blood agar have a smooth, white and convex appearance

Figure 4

This thin line of hydrogen sulfide production (arrow) in a triple sugar iron slant is one of the key features in the identification of Francisella philomiragia