A 12-year-old boy presented to the Paediatric Emergency Department with a three-month history of daily fever, migratory arthritis, angular cheilitis, a reported 5 kg weight loss, and malaise. Past medical history was unremarkable other than immigration from Pakistan to Canada at the age of 7. Family history was significant for parental consanguinity (first cousins), but both parents and an older brother (17 years) and sister (19 years) were reported as being well.
He was admitted to hospital for a diagnostic evaluation and was found to have systemic inflammation (elevated c-reactive protein, erythrocyte sedimentation rate, ferritin, sCD-163, and sCD-25) concerning macrophage activation syndrome (MAS). He underwent an extensive workup for potential secondary causes of this inflammation. Bacterial blood culture, EBV/CMV, Toxoplasma gondii, parvovirus B19 and Legionella serologies, respiratory virus multiplex PCR, and TB skin test were negative. An abdominal ultrasound and bone marrow aspirate showed no evidence of malignancy. An autoantibody panel was sent and was positive only for anti-nuclear antibody (1 : 160, speckled pattern). A chest X-ray was performed and was normal.
At this time, a clinical diagnosis of systemic onset juvenile idiopathic arthritis was made. Treatment with oral prednisone (60 mg orally, once daily) was initiated on day 3 of admission, which resulted in rapid resolution of the fevers, arthritis, and cheilitis. He was discharged home on day 6 of admission with follow-up planned with Rheumatology.
He presented to the Emergency Department 3 weeks later with a three-day history of fever, cough, and pleuritic chest pain. Chest X-ray revealed bilateral, multifocal pulmonary nodules and chest CT confirmed the presence of bilateral, predominantly apical homogeneous nodules (5-20 mm in diameter) and hilar lymphadenopathy (Figure 1(a)).
The main differential diagnosis of this child's pulmonary nodules was infectious. A bronchoalveolar lavage revealed the presence of Aspergillus fumigatus and treatment with voriconazole was subsequently initiated.