Toxocariasis as a cause of new pulmonary infiltrates

Patients with new pulmonary infiltrates on chest computed tomography (CT) scans at a tertiary centre in South Korea.

To demonstrate associations among radiological changes, blood eosinophilia (E) and Toxocara (T) seropositivity.

We retrospectively reviewed blood eosinophilia, Toxocara seropositivity, history of raw meat intake and radiological features, and divided study patients into four groups according to blood eosinophilia and Toxocara seropositivity.

Among 150 patients, 62 were E- and T-positive (E+T+), 45 were E-negative and T-positive (E-T+), 7 were E-positive and T-negative (E+T-), and 36 were E- and T-negative (E-T-). History of raw meat intake was found in 95 (63%) patients. The type and number of lesions on CT did not show any significant differences among the four groups. Among 119 patients who were not diagnosed with a specific disease, transient or migrating lesions were seen in 93% of E+T+, 93% of E-T+, 80% of E+T- and 52% of E-T- patients (P < 0.0001). Furthermore, the frequencies of migrating or new lesions and improvement were significantly higher in the Toxocara-positive group (88/95, 93%) than in the Toxocara-negative group (14/24, 58%; P = 0.002).

Transient and migratory pulmonary infiltrates on chest CT scans were associated with blood eosinophilia and Toxocara seropositivity. Clinicians should consider asymptomatic toxocariasis as a cause of unexplained new pulmonary infiltrates in countries with dietary habits of raw meat intake.